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151c9c72 |
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22-Mar-2024 |
Eric Dumazet <edumazet@google.com> |
tcp: properly terminate timers for kernel sockets We had various syzbot reports about tcp timers firing after the corresponding netns has been dismantled. Fortunately Josef Bacik could trigger the issue more often, and could test a patch I wrote two years ago. When TCP sockets are closed, we call inet_csk_clear_xmit_timers() to 'stop' the timers. inet_csk_clear_xmit_timers() can be called from any context, including when socket lock is held. This is the reason it uses sk_stop_timer(), aka del_timer(). This means that ongoing timers might finish much later. For user sockets, this is fine because each running timer holds a reference on the socket, and the user socket holds a reference on the netns. For kernel sockets, we risk that the netns is freed before timer can complete, because kernel sockets do not hold reference on the netns. This patch adds inet_csk_clear_xmit_timers_sync() function that using sk_stop_timer_sync() to make sure all timers are terminated before the kernel socket is released. Modules using kernel sockets close them in their netns exit() handler. Also add sock_not_owned_by_me() helper to get LOCKDEP support : inet_csk_clear_xmit_timers_sync() must not be called while socket lock is held. It is very possible we can revert in the future commit 3a58f13a881e ("net: rds: acquire refcount on TCP sockets") which attempted to solve the issue in rds only. (net/smc/af_smc.c and net/mptcp/subflow.c have similar code) We probably can remove the check_net() tests from tcp_out_of_resources() and __tcp_close() in the future. Reported-by: Josef Bacik <josef@toxicpanda.com> Closes: https://lore.kernel.org/netdev/20240314210740.GA2823176@perftesting/ Fixes: 26abe14379f8 ("net: Modify sk_alloc to not reference count the netns of kernel sockets.") Fixes: 8a68173691f0 ("net: sk_clone_lock() should only do get_net() if the parent is not a kernel socket") Link: https://lore.kernel.org/bpf/CANn89i+484ffqb93aQm1N-tjxxvb3WDKX0EbD7318RwRgsatjw@mail.gmail.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Josef Bacik <josef@toxicpanda.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/20240322135732.1535772-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
683a67da |
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08-Mar-2024 |
Jason Xing <kernelxing@tencent.com> |
tcp: annotate a data-race around sysctl_tcp_wmem[0] When reading wmem[0], it could be changed concurrently without READ_ONCE() protection. So add one annotation here. Signed-off-by: Jason Xing <kernelxing@tencent.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
716edc97 |
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07-Mar-2024 |
Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru> |
tcp: fix incorrect parameter validation in the do_tcp_getsockopt() function The 'len' variable can't be negative when assigned the result of 'min_t' because all 'min_t' parameters are cast to unsigned int, and then the minimum one is chosen. To fix the logic, check 'len' as read from 'optlen', where the types of relevant variables are (signed) int. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
490a79fa |
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06-Mar-2024 |
Eric Dumazet <edumazet@google.com> |
net: introduce include/net/rps.h Move RPS related structures and helpers from include/linux/netdevice.h and include/net/sock.h to a new include file. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240306160031.874438-18-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
345a6e26 |
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01-Mar-2024 |
Eric Dumazet <edumazet@google.com> |
tcp: align tcp_sock_write_rx group Stephen Rothwell and kernel test robot reported that some arches (parisc, hexagon) and/or compilers would not like blamed commit. Lets make sure tcp_sock_write_rx group does not start with a hole. While we are at it, correct tcp_sock_write_tx CACHELINE_ASSERT_GROUP_SIZE() since after the blamed commit, we went to 105 bytes. Fixes: 99123622050f ("tcp: remove some holes in struct tcp_sock") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/netdev/20240301121108.5d39e4f9@canb.auug.org.au/ Closes: https://lore.kernel.org/oe-kbuild-all/202403011451.csPYOS3C-lkp@intel.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Tested-by: Simon Horman <horms@kernel.org> # build-tested Link: https://lore.kernel.org/r/20240301171945.2958176-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
119ff048 |
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08-Feb-2024 |
Eric Dumazet <edumazet@google.com> |
tcp: move tp->scaling_ratio to tcp_sock_read_txrx group tp->scaling_ratio is a read mostly field, used in rx and tx fast paths. Fixes: d5fed5addb2b ("tcp: reorganize tcp_sock fast path variables") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Coco Li <lixiaoyan@google.com> Cc: Wei Wang <weiwan@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
577e4432 |
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25-Jan-2024 |
Eric Dumazet <edumazet@google.com> |
tcp: add sanity checks to rx zerocopy TCP rx zerocopy intent is to map pages initially allocated from NIC drivers, not pages owned by a fs. This patch adds to can_map_frag() these additional checks: - Page must not be a compound one. - page->mapping must be NULL. This fixes the panic reported by ZhangPeng. syzbot was able to loopback packets built with sendfile(), mapping pages owned by an ext4 file to TCP rx zerocopy. r3 = socket$inet_tcp(0x2, 0x1, 0x0) mmap(&(0x7f0000ff9000/0x4000)=nil, 0x4000, 0x0, 0x12, r3, 0x0) r4 = socket$inet_tcp(0x2, 0x1, 0x0) bind$inet(r4, &(0x7f0000000000)={0x2, 0x4e24, @multicast1}, 0x10) connect$inet(r4, &(0x7f00000006c0)={0x2, 0x4e24, @empty}, 0x10) r5 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0) fallocate(r5, 0x0, 0x0, 0x85b8) sendfile(r4, r5, 0x0, 0x8ba0) getsockopt$inet_tcp_TCP_ZEROCOPY_RECEIVE(r4, 0x6, 0x23, &(0x7f00000001c0)={&(0x7f0000ffb000/0x3000)=nil, 0x3000, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, &(0x7f0000000440)=0x40) r6 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0) Fixes: 93ab6cc69162 ("tcp: implement mmap() for zero copy receive") Link: https://lore.kernel.org/netdev/5106a58e-04da-372a-b836-9d3d0bd2507b@huawei.com/T/ Reported-and-bisected-by: ZhangPeng <zhangpeng362@huawei.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Arjun Roy <arjunroy@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: linux-mm@vger.kernel.org Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7267e8dc |
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19-Jan-2024 |
Salvatore Dipietro <dipiets@amazon.com> |
tcp: Add memory barrier to tcp_push() On CPUs with weak memory models, reads and updates performed by tcp_push to the sk variables can get reordered leaving the socket throttled when it should not. The tasklet running tcp_wfree() may also not observe the memory updates in time and will skip flushing any packets throttled by tcp_push(), delaying the sending. This can pathologically cause 40ms extra latency due to bad interactions with delayed acks. Adding a memory barrier in tcp_push removes the bug, similarly to the previous commit bf06200e732d ("tcp: tsq: fix nonagle handling"). smp_mb__after_atomic() is used to not incur in unnecessary overhead on x86 since not affected. Patch has been tested using an AWS c7g.2xlarge instance with Ubuntu 22.04 and Apache Tomcat 9.0.83 running the basic servlet below: import java.io.IOException; import java.io.OutputStreamWriter; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class HelloWorldServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); OutputStreamWriter osw = new OutputStreamWriter(response.getOutputStream(),"UTF-8"); String s = "a".repeat(3096); osw.write(s,0,s.length()); osw.flush(); } } Load was applied using wrk2 (https://github.com/kinvolk/wrk2) from an AWS c6i.8xlarge instance. Before the patch an additional 40ms latency from P99.99+ values is observed while, with the patch, the extra latency disappears. No patch and tcp_autocorking=1 ./wrk -t32 -c128 -d40s --latency -R10000 http://172.31.60.173:8080/hello/hello ... 50.000% 0.91ms 75.000% 1.13ms 90.000% 1.46ms 99.000% 1.74ms 99.900% 1.89ms 99.990% 41.95ms <<< 40+ ms extra latency 99.999% 48.32ms 100.000% 48.96ms With patch and tcp_autocorking=1 ./wrk -t32 -c128 -d40s --latency -R10000 http://172.31.60.173:8080/hello/hello ... 50.000% 0.90ms 75.000% 1.13ms 90.000% 1.45ms 99.000% 1.72ms 99.900% 1.83ms 99.990% 2.11ms <<< no 40+ ms extra latency 99.999% 2.53ms 100.000% 2.62ms Patch has been also tested on x86 (m7i.2xlarge instance) which it is not affected by this issue and the patch doesn't introduce any additional delay. Fixes: 7aa5470c2c09 ("tcp: tsq: move tsq_flags close to sk_wmem_alloc") Signed-off-by: Salvatore Dipietro <dipiets@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240119190133.43698-1-dipiets@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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#
d5fed5ad |
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04-Dec-2023 |
Coco Li <lixiaoyan@google.com> |
tcp: reorganize tcp_sock fast path variables The variables are organized according in the following way: - TX read-mostly hotpath cache lines - TXRX read-mostly hotpath cache lines - RX read-mostly hotpath cache lines - TX read-write hotpath cache line - TXRX read-write hotpath cache line - RX read-write hotpath cache line Fastpath cachelines end after rcvq_space. Cache line boundaries are enforced only between read-mostly and read-write. That is, if read-mostly tx cachelines bleed into read-mostly txrx cachelines, we do not care. We care about the boundaries between read and write cachelines because we want to prevent false sharing. Fast path variables span cache lines before change: 12 Fast path variables span cache lines after change: 8 Suggested-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Wei Wang <weiwan@google.com> Signed-off-by: Coco Li <lixiaoyan@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20231204201232.520025-3-lixiaoyan@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
91051f00 |
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01-Dec-2023 |
Guillaume Nault <gnault@redhat.com> |
tcp: Dump bound-only sockets in inet_diag. Walk the hashinfo->bhash2 table so that inet_diag can dump TCP sockets that are bound but haven't yet called connect() or listen(). The code is inspired by the ->lhash2 loop. However there's no manual test of the source port, since this kind of filtering is already handled by inet_diag_bc_sk(). Also, a maximum of 16 sockets are dumped at a time, to avoid running with bh disabled for too long. There's no TCP state for bound but otherwise inactive sockets. Such sockets normally map to TCP_CLOSE. However, "ss -l", which is supposed to only dump listening sockets, actually requests the kernel to dump sockets in either the TCP_LISTEN or TCP_CLOSE states. To avoid dumping bound-only sockets with "ss -l", we therefore need to define a new pseudo-state (TCP_BOUND_INACTIVE) that user space will be able to set explicitly. With an IPv4, an IPv6 and an IPv6-only socket, bound respectively to 40000, 64000, 60000, an updated version of iproute2 could work as follow: $ ss -t state bound-inactive Recv-Q Send-Q Local Address:Port Peer Address:Port Process 0 0 0.0.0.0:40000 0.0.0.0:* 0 0 [::]:60000 [::]:* 0 0 *:64000 *:* Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/b3a84ae61e19c06806eea9c602b3b66e8f0cfc81.1701362867.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
9fd7874c |
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04-Dec-2023 |
Jens Axboe <axboe@kernel.dk> |
iov_iter: replace import_single_range() with import_ubuf() With the removal of the 'iov' argument to import_single_range(), the two functions are now fully identical. Convert the import_single_range() callers to import_ubuf(), and remove the former fully. Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20231204174827.1258875-3-axboe@kernel.dk Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
6ac805d1 |
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04-Dec-2023 |
Jens Axboe <axboe@kernel.dk> |
iov_iter: remove unused 'iov' argument from import_single_range() It is entirely unused, just get rid of it. Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20231204174827.1258875-2-axboe@kernel.dk Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
97028173 |
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13-Dec-2023 |
Jakub Kicinski <kuba@kernel.org> |
Revert "tcp: disable tcp_autocorking for socket when TCP_NODELAY flag is set" This reverts commit f3f32a356c0d2379d4431364e74f101f8f075ce3. Paolo reports that the change disables autocorking even after the userspace sets TCP_CORK. Fixes: f3f32a356c0d ("tcp: disable tcp_autocorking for socket when TCP_NODELAY flag is set") Link: https://lore.kernel.org/r/0d30d5a41d3ac990573016308aaeacb40a9dc79f.camel@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
f3f32a35 |
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08-Dec-2023 |
Salvatore Dipietro <dipiets@amazon.com> |
tcp: disable tcp_autocorking for socket when TCP_NODELAY flag is set Based on the tcp man page, if TCP_NODELAY is set, it disables Nagle's algorithm and packets are sent as soon as possible. However in the `tcp_push` function where autocorking is evaluated the `nonagle` value set by TCP_NODELAY is not considered which can trigger unexpected corking of packets and induce delays. For example, if two packets are generated as part of a server's reply, if the first one is not transmitted on the wire quickly enough, the second packet can trigger the autocorking in `tcp_push` and be delayed instead of sent as soon as possible. It will either wait for additional packets to be coalesced or an ACK from the client before transmitting the corked packet. This can interact badly if the receiver has tcp delayed acks enabled, introducing 40ms extra delay in completion times. It is not always possible to control who has delayed acks set, but it is possible to adjust when and how autocorking is triggered. Patch prevents autocorking if the TCP_NODELAY flag is set on the socket. Patch has been tested using an AWS c7g.2xlarge instance with Ubuntu 22.04 and Apache Tomcat 9.0.83 running the basic servlet below: import java.io.IOException; import java.io.OutputStreamWriter; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class HelloWorldServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); OutputStreamWriter osw = new OutputStreamWriter(response.getOutputStream(),"UTF-8"); String s = "a".repeat(3096); osw.write(s,0,s.length()); osw.flush(); } } Load was applied using wrk2 (https://github.com/kinvolk/wrk2) from an AWS c6i.8xlarge instance. With the current auto-corking behavior and TCP_NODELAY set an additional 40ms latency from P99.99+ values are observed. With the patch applied we see no occurrences of 40ms latencies. The patch has also been tested with iperf and uperf benchmarks and no regression was observed. # No patch with tcp_autocorking=1 and TCP_NODELAY set on all sockets ./wrk -t32 -c128 -d40s --latency -R10000 http://172.31.49.177:8080/hello/hello' ... 50.000% 0.91ms 75.000% 1.12ms 90.000% 1.46ms 99.000% 1.73ms 99.900% 1.96ms 99.990% 43.62ms <<< 40+ ms extra latency 99.999% 48.32ms 100.000% 49.34ms # With patch ./wrk -t32 -c128 -d40s --latency -R10000 http://172.31.49.177:8080/hello/hello' ... 50.000% 0.89ms 75.000% 1.13ms 90.000% 1.44ms 99.000% 1.67ms 99.900% 1.78ms 99.990% 2.27ms <<< no 40+ ms extra latency 99.999% 3.71ms 100.000% 4.57ms Fixes: f54b311142a9 ("tcp: auto corking") Signed-off-by: Salvatore Dipietro <dipiets@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
965c00e4 |
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04-Dec-2023 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Limit TCP_AO_REPAIR to non-listen sockets Listen socket is not an established TCP connection, so setsockopt(TCP_AO_REPAIR) doesn't have any impact. Restrict this uAPI for listen sockets. Fixes: faadfaba5e01 ("net/tcp: Add TCP_AO_REPAIR") Signed-off-by: Dmitry Safonov <dima@arista.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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58d3aade |
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04-Dec-2023 |
Paolo Abeni <pabeni@redhat.com> |
tcp: fix mid stream window clamp. After the blamed commit below, if the user-space application performs window clamping when tp->rcv_wnd is 0, the TCP socket will never be able to announce a non 0 receive window, even after completely emptying the receive buffer and re-setting the window clamp to higher values. Refactor tcp_set_window_clamp() to address the issue: when the user decreases the current clamp value, set rcv_ssthresh according to the same logic used at buffer initialization, but ensuring reserved mem provisioning. To avoid code duplication factor-out the relevant bits from tcp_adjust_rcv_ssthresh() in a new helper and reuse it in the above scenario. When increasing the clamp value, give the rcv_ssthresh a chance to grow according to previously implemented heuristic. Fixes: 3aa7857fe1d7 ("tcp: enable mid stream window clamp") Reported-by: David Gibson <david@gibson.dropbear.id.au> Reported-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/705dad54e6e6e9a010e571bf58e0b35a8ae70503.1701706073.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
faadfaba |
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23-Oct-2023 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Add TCP_AO_REPAIR Add TCP_AO_REPAIR setsockopt(), getsockopt(). They let a user to repair TCP-AO ISNs/SNEs. Also let the user hack around when (tp->repair) is on and add ao_info on a socket in any supported state. As SNEs now can be read/written at any moment, use WRITE_ONCE()/READ_ONCE() to set/read them. Signed-off-by: Dmitry Safonov <dima@arista.com> Acked-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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ef84703a |
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23-Oct-2023 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Add TCP-AO getsockopt()s Introduce getsockopt(TCP_AO_GET_KEYS) that lets a user get TCP-AO keys and their properties from a socket. The user can provide a filter to match the specific key to be dumped or ::get_all = 1 may be used to dump all keys in one syscall. Add another getsockopt(TCP_AO_INFO) for providing per-socket/per-ao_info stats: packet counters, Current_key/RNext_key and flags like ::ao_required and ::accept_icmps. Co-developed-by: Francesco Ruggeri <fruggeri@arista.com> Signed-off-by: Francesco Ruggeri <fruggeri@arista.com> Co-developed-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Acked-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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2717b5ad |
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23-Oct-2023 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Add tcp_hash_fail() ratelimited logs Add a helper for logging connection-detailed messages for failed TCP hash verification (both MD5 and AO). Co-developed-by: Francesco Ruggeri <fruggeri@arista.com> Signed-off-by: Francesco Ruggeri <fruggeri@arista.com> Co-developed-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Acked-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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0a3a8090 |
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23-Oct-2023 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Verify inbound TCP-AO signed segments Now there is a common function to verify signature on TCP segments: tcp_inbound_hash(). It has checks for all possible cross-interactions with MD5 signs as well as with unsigned segments. The rules from RFC5925 are: (1) Any TCP segment can have at max only one signature. (2) TCP connections can't switch between using TCP-MD5 and TCP-AO. (3) TCP-AO connections can't stop using AO, as well as unsigned connections can't suddenly start using AO. Co-developed-by: Francesco Ruggeri <fruggeri@arista.com> Signed-off-by: Francesco Ruggeri <fruggeri@arista.com> Co-developed-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Acked-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f7dca36f |
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23-Oct-2023 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Add tcp_parse_auth_options() Introduce a helper that: (1) shares the common code with TCP-MD5 header options parsing (2) looks for hash signature only once for both TCP-MD5 and TCP-AO (3) fails with -EEXIST if any TCP sign option is present twice, see RFC5925 (2.2): ">> A single TCP segment MUST NOT have more than one TCP-AO in its options sequence. When multiple TCP-AOs appear, TCP MUST discard the segment." Co-developed-by: Francesco Ruggeri <fruggeri@arista.com> Signed-off-by: Francesco Ruggeri <fruggeri@arista.com> Co-developed-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Acked-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4954f17d |
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23-Oct-2023 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Introduce TCP_AO setsockopt()s Add 3 setsockopt()s: 1. TCP_AO_ADD_KEY to add a new Master Key Tuple (MKT) on a socket 2. TCP_AO_DEL_KEY to delete present MKT from a socket 3. TCP_AO_INFO to change flags, Current_key/RNext_key on a TCP-AO sk Userspace has to introduce keys on every socket it wants to use TCP-AO option on, similarly to TCP_MD5SIG/TCP_MD5SIG_EXT. RFC5925 prohibits definition of MKTs that would match the same peer, so do sanity checks on the data provided by userspace. Be as conservative as possible, including refusal of defining MKT on an established connection with no AO, removing the key in-use and etc. (1) and (2) are to be used by userspace key manager to add/remove keys. (3) main purpose is to set RNext_key, which (as prescribed by RFC5925) is the KeyID that will be requested in TCP-AO header from the peer to sign their segments with. At this moment the life of ao_info ends in tcp_v4_destroy_sock(). Co-developed-by: Francesco Ruggeri <fruggeri@arista.com> Signed-off-by: Francesco Ruggeri <fruggeri@arista.com> Co-developed-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Salam Noureddine <noureddine@arista.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Acked-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8c73b263 |
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23-Oct-2023 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Prepare tcp_md5sig_pool for TCP-AO TCP-AO, similarly to TCP-MD5, needs to allocate tfms on a slow-path, which is setsockopt() and use crypto ahash requests on fast paths, which are RX/TX softirqs. Also, it needs a temporary/scratch buffer for preparing the hash. Rework tcp_md5sig_pool in order to support other hashing algorithms than MD5. It will make it possible to share pre-allocated crypto_ahash descriptors and scratch area between all TCP hash users. Internally tcp_sigpool calls crypto_clone_ahash() API over pre-allocated crypto ahash tfm. Kudos to Herbert, who provided this new crypto API. I was a little concerned over GFP_ATOMIC allocations of ahash and crypto_request in RX/TX (see tcp_sigpool_start()), so I benchmarked both "backends" with different algorithms, using patched version of iperf3[2]. On my laptop with i7-7600U @ 2.80GHz: clone-tfm per-CPU-requests TCP-MD5 2.25 Gbits/sec 2.30 Gbits/sec TCP-AO(hmac(sha1)) 2.53 Gbits/sec 2.54 Gbits/sec TCP-AO(hmac(sha512)) 1.67 Gbits/sec 1.64 Gbits/sec TCP-AO(hmac(sha384)) 1.77 Gbits/sec 1.80 Gbits/sec TCP-AO(hmac(sha224)) 1.29 Gbits/sec 1.30 Gbits/sec TCP-AO(hmac(sha3-512)) 481 Mbits/sec 480 Mbits/sec TCP-AO(hmac(md5)) 2.07 Gbits/sec 2.12 Gbits/sec TCP-AO(hmac(rmd160)) 1.01 Gbits/sec 995 Mbits/sec TCP-AO(cmac(aes128)) [not supporetd yet] 2.11 Gbits/sec So, it seems that my concerns don't have strong grounds and per-CPU crypto_request allocation can be dropped/removed from tcp_sigpool once ciphers get crypto_clone_ahash() support. [1]: https://lore.kernel.org/all/ZDefxOq6Ax0JeTRH@gondor.apana.org.au/T/#u [2]: https://github.com/0x7f454c46/iperf/tree/tcp-md5-ao Signed-off-by: Dmitry Safonov <dima@arista.com> Reviewed-by: Steen Hegelund <Steen.Hegelund@microchip.com> Acked-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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a77a0f5c |
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19-Oct-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: add TCPI_OPT_USEC_TS Add the ability to report in tcp_info.tcpi_options if a flow is using usec resolution in TCP TS val. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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614e8316 |
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19-Oct-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: add support for usec resolution in TCP TS values Back in 2015, Van Jacobson suggested to use usec resolution in TCP TS values. This has been implemented in our private kernels. Goals were : 1) better observability of delays in networking stacks. 2) better disambiguation of events based on TSval/ecr values. 3) building block for congestion control modules needing usec resolution. Back then we implemented a schem based on private SYN options to negotiate the feature. For upstream submission, we chose to use a route attribute, because this feature is probably going to be used in private networks [1] [2]. ip route add 10/8 ... features tcp_usec_ts Note that RFC 7323 recommends a "timestamp clock frequency in the range 1 ms to 1 sec per tick.", but also mentions "the maximum acceptable clock frequency is one tick every 59 ns." [1] Unfortunately RFC 7323 5.5 (Outdated Timestamps) suggests to invalidate TS.Recent values after a flow was idle for more than 24 days. This is the part making usec_ts a problem for peers following this recommendation for long living idle flows. [2] Attempts to standardize usec ts went nowhere: https://www.ietf.org/proceedings/97/slides/slides-97-tcpm-tcp-options-for-low-latency-00.pdf https://datatracker.ietf.org/doc/draft-wang-tcpm-low-latency-opt/ Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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16cf6477 |
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19-Oct-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: replace tcp_time_stamp_raw() In preparation of usec TCP TS support, remove tcp_time_stamp_raw() in favor of tcp_clock_ts() helper. This helper will return a suitable 32bit result to feed TS values, depending on a socket field. Also add tcp_tw_tsval() and tcp_rsk_tsval() helpers to factorize the details. We do not yet support usec timestamps. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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2a7c8d29 |
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19-Oct-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: introduce tcp_clock_ms() It delivers current TCP time stamp in ms unit, and is used in place of confusing tcp_time_stamp_raw() It is the same family than tcp_clock_ns() and tcp_clock_ms(). tcp_time_stamp_raw() will be replaced later for TSval contexts with a more descriptive name. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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95b9a87c |
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05-Oct-2023 |
David Morley <morleyd@google.com> |
tcp: record last received ipv6 flowlabel In order to better estimate whether a data packet has been retransmitted or is the result of a TLP, we save the last received ipv6 flowlabel. To make space for this field we resize the "ato" field in inet_connection_sock as the current value of TCP_DELACK_MAX can be fully contained in 8 bits and add a compile_time_assert ensuring this field is the required size. v2: addressed kernel bot feedback about dccp_delack_timer() v3: addressed build error introduced by commit bbf80d713fe7 ("tcp: derive delack_max from rto_min") Signed-off-by: David Morley <morleyd@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Tested-by: David Morley <morleyd@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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bbf80d71 |
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20-Sep-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: derive delack_max from rto_min While BPF allows to set icsk->->icsk_delack_max and/or icsk->icsk_rto_min, we have an ip route attribute (RTAX_RTO_MIN) to be able to tune rto_min, but nothing to consequently adjust max delayed ack, which vary from 40ms to 200 ms (TCP_DELACK_{MIN|MAX}). This makes RTAX_RTO_MIN of almost no practical use, unless customers are in big trouble. Modern days datacenter communications want to set rto_min to ~5 ms, and the max delayed ack one jiffie smaller to avoid spurious retransmits. After this patch, an "rto_min 5" route attribute will effectively lower max delayed ack timers to 4 ms. Note in the following ss output, "rto:6 ... ato:4" $ ss -temoi dst XXXXXX State Recv-Q Send-Q Local Address:Port Peer Address:Port Process ESTAB 0 0 [2002:a05:6608:295::]:52950 [2002:a05:6608:297::]:41597 ino:255134 sk:1001 <-> skmem:(r0,rb1707063,t872,tb262144,f0,w0,o0,bl0,d0) ts sack cubic wscale:8,8 rto:6 rtt:0.02/0.002 ato:4 mss:4096 pmtu:4500 rcvmss:536 advmss:4096 cwnd:10 bytes_sent:54823160 bytes_acked:54823121 bytes_received:54823120 segs_out:1370582 segs_in:1370580 data_segs_out:1370579 data_segs_in:1370578 send 16.4Gbps pacing_rate 32.6Gbps delivery_rate 1.72Gbps delivered:1370579 busy:26920ms unacked:1 rcv_rtt:34.615 rcv_space:65920 rcv_ssthresh:65535 minrtt:0.015 snd_wnd:65536 While we could argue this patch fixes a bug with RTAX_RTO_MIN, I do not add a Fixes: tag, so that we can soak it a bit before asking backports to stable branches. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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3868ab0f |
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14-Sep-2023 |
Aananth V <aananthv@google.com> |
tcp: new TCP_INFO stats for RTO events The 2023 SIGCOMM paper "Improving Network Availability with Protective ReRoute" has indicated Linux TCP's RTO-triggered txhash rehashing can effectively reduce application disruption during outages. To better measure the efficacy of this feature, this patch adds three more detailed stats during RTO recovery and exports via TCP_INFO. Applications and monitoring systems can leverage this data to measure the network path diversity and end-to-end repair latency during network outages to improve their network infrastructure. The following counters are added to tcp_sock in order to track RTO events over the lifetime of a TCP socket. 1. u16 total_rto - Counts the total number of RTO timeouts. 2. u16 total_rto_recoveries - Counts the total number of RTO recoveries. 3. u32 total_rto_time - Counts the total time spent (ms) in RTO recoveries. (time spent in CA_Loss and CA_Recovery states) To compute total_rto_time, we add a new u32 rto_stamp field to tcp_sock. rto_stamp records the start timestamp (ms) of the last RTO recovery (CA_Loss). Corresponding fields are also added to the tcp_info struct. Signed-off-by: Aananth V <aananthv@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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72bf4f17 |
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19-Oct-2023 |
Eric Dumazet <edumazet@google.com> |
net: do not leave an empty skb in write queue Under memory stress conditions, tcp_sendmsg_locked() might call sk_stream_wait_memory(), thus releasing the socket lock. If a fresh skb has been allocated prior to this, we should not leave it in the write queue otherwise tcp_write_xmit() could panic. This apparently does not happen often, but a future change in __sk_mem_raise_allocated() that Shakeel and others are considering would increase chances of being hurt. Under discussion is to remove this controversial part: /* Fail only if socket is _under_ its sndbuf. * In this case we cannot block, so that we have to fail. */ if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) { /* Force charge with __GFP_NOFAIL */ if (memcg_charge && !charged) { mem_cgroup_charge_skmem(sk->sk_memcg, amt, gfp_memcg_charge() | __GFP_NOFAIL); } return 1; } Fixes: fdfc5c8594c2 ("tcp: remove empty skb from write queue in error cases") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Link: https://lore.kernel.org/r/20231019112457.1190114-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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419ce133 |
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11-Oct-2023 |
Paolo Abeni <pabeni@redhat.com> |
tcp: allow again tcp_disconnect() when threads are waiting As reported by Tom, .NET and applications build on top of it rely on connect(AF_UNSPEC) to async cancel pending I/O operations on TCP socket. The blamed commit below caused a regression, as such cancellation can now fail. As suggested by Eric, this change addresses the problem explicitly causing blocking I/O operation to terminate immediately (with an error) when a concurrent disconnect() is executed. Instead of tracking the number of threads blocked on a given socket, track the number of disconnect() issued on such socket. If such counter changes after a blocking operation releasing and re-acquiring the socket lock, error out the current operation. Fixes: 4faeee0cf8a5 ("tcp: deny tcp_disconnect() when threads are waiting") Reported-by: Tom Deseyn <tdeseyn@redhat.com> Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1886305 Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/f3b95e47e3dbed840960548aebaa8d954372db41.1697008693.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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9b7177b1 |
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25-Sep-2023 |
John Fastabend <john.fastabend@gmail.com> |
bpf: tcp_read_skb needs to pop skb regardless of seq Before fix e5c6de5fa0258 tcp_read_skb() would increment the tp->copied-seq value. This (as described in the commit) would cause an error for apps because once that is incremented the application might believe there is no data to be read. Then some apps would stall or abort believing no data is available. However, the fix is incomplete because it introduces another issue in the skb dequeue. The loop does tcp_recv_skb() in a while loop to consume as many skbs as possible. The problem is the call is ... tcp_recv_skb(sk, seq, &offset) ... where 'seq' is: u32 seq = tp->copied_seq; Now we can hit a case where we've yet incremented copied_seq from BPF side, but then tcp_recv_skb() fails this test ... if (offset < skb->len || (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) ... so that instead of returning the skb we call tcp_eat_recv_skb() which frees the skb. This is because the routine believes the SKB has been collapsed per comment: /* This looks weird, but this can happen if TCP collapsing * splitted a fat GRO packet, while we released socket lock * in skb_splice_bits() */ This can't happen here we've unlinked the full SKB and orphaned it. Anyways it would confuse any BPF programs if the data were suddenly moved underneath it. To fix this situation do simpler operation and just skb_peek() the data of the queue followed by the unlink. It shouldn't need to check this condition and tcp_read_skb() reads entire skbs so there is no need to handle the 'offset!=0' case as we would see in tcp_read_sock(). Fixes: e5c6de5fa0258 ("bpf, sockmap: Incorrectly handling copied_seq") Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230926035300.135096-2-john.fastabend@gmail.com
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e3390b30 |
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31-Aug-2023 |
Eric Dumazet <edumazet@google.com> |
net: annotate data-races around sk->sk_tsflags sk->sk_tsflags can be read locklessly, add corresponding annotations. Fixes: b9f40e21ef42 ("net-timestamp: move timestamp flags out of sk_flags") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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350f6bbc |
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24-Jul-2023 |
Matthew Wilcox (Oracle) <willy@infradead.org> |
mm: allow per-VMA locks on file-backed VMAs Remove the TCP layering violation by allowing per-VMA locks on all VMAs. The fault path will immediately fail in handle_mm_fault(). There may be a small performance reduction from this patch as a little unnecessary work will be done on each page fault. See later patches for the improvement. Link: https://lkml.kernel.org/r/20230724185410.1124082-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Cc: Arjun Roy <arjunroy@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Punit Agrawal <punit.agrawal@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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08e39c0d |
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16-Aug-2023 |
Eric Dumazet <edumazet@google.com> |
inet: move inet->defer_connect to inet->inet_flags Make room in struct inet_sock by removing this bit field, using one available bit in inet_flags instead. Also move local_port_range to fill the resulting hole, saving 8 bytes on 64bit arches. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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6e97ba55 |
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04-Aug-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: set TCP_DEFER_ACCEPT locklessly rskq_defer_accept field can be read/written without the need of holding the socket lock. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a81722dd |
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04-Aug-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: set TCP_LINGER2 locklessly tp->linger2 can be set locklessly as long as readers use READ_ONCE(). Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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84485080 |
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04-Aug-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: set TCP_KEEPCNT locklessly tp->keepalive_probes can be set locklessly, readers are already taking care of this field being potentially set by other threads. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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6fd70a6b |
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04-Aug-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: set TCP_KEEPINTVL locklessly tp->keepalive_intvl can be set locklessly, readers are already taking care of this field being potentially set by other threads. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d58f2e15 |
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04-Aug-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: set TCP_USER_TIMEOUT locklessly icsk->icsk_user_timeout can be set locklessly, if all read sides use READ_ONCE(). Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d44fd4a7 |
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04-Aug-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: set TCP_SYNCNT locklessly icsk->icsk_syn_retries can safely be set without locking the socket. We have to add READ_ONCE() annotations in tcp_fastopen_synack_timer() and tcp_write_timeout(). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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dfa2f048 |
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17-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: get rid of sysctl_tcp_adv_win_scale With modern NIC drivers shifting to full page allocations per received frame, we face the following issue: TCP has one per-netns sysctl used to tweak how to translate a memory use into an expected payload (RWIN), in RX path. tcp_win_from_space() implementation is limited to few cases. For hosts dealing with various MSS, we either under estimate or over estimate the RWIN we send to the remote peers. For instance with the default sysctl_tcp_adv_win_scale value, we expect to store 50% of payload per allocated chunk of memory. For the typical use of MTU=1500 traffic, and order-0 pages allocations by NIC drivers, we are sending too big RWIN, leading to potential tcp collapse operations, which are extremely expensive and source of latency spikes. This patch makes sysctl_tcp_adv_win_scale obsolete, and instead uses a per socket scaling factor, so that we can precisely adjust the RWIN based on effective skb->len/skb->truesize ratio. This patch alone can double TCP receive performance when receivers are too slow to drain their receive queue, or by allowing a bigger RWIN when MSS is close to PAGE_SIZE. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Link: https://lore.kernel.org/r/20230717152917.751987-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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70f360dd |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around fastopenq.max_qlen This field can be read locklessly. Fixes: 1536e2857bd3 ("tcp: Add a TCP_FASTOPEN socket option to get a max backlog on its listner") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-12-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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26023e91 |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around icsk->icsk_user_timeout This field can be read locklessly from do_tcp_getsockopt() Fixes: dca43c75e7e5 ("tcp: Add TCP_USER_TIMEOUT socket option.") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-11-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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1aeb87bc |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around tp->notsent_lowat tp->notsent_lowat can be read locklessly from do_tcp_getsockopt() and tcp_poll(). Fixes: c9bee3b7fdec ("tcp: TCP_NOTSENT_LOWAT socket option") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-10-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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ae488c74 |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around rskq_defer_accept do_tcp_getsockopt() reads rskq_defer_accept while another cpu might change its value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-9-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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9df5335c |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around tp->linger2 do_tcp_getsockopt() reads tp->linger2 while another cpu might change its value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-8-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
3a037f0f |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around icsk->icsk_syn_retries do_tcp_getsockopt() and reqsk_timer_handler() read icsk->icsk_syn_retries while another cpu might change its value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-7-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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6e5e1de6 |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around tp->keepalive_probes do_tcp_getsockopt() reads tp->keepalive_probes while another cpu might change its value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-6-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
5ecf9d4f |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around tp->keepalive_intvl do_tcp_getsockopt() reads tp->keepalive_intvl while another cpu might change its value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
4164245c |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around tp->keepalive_time do_tcp_getsockopt() reads tp->keepalive_time while another cpu might change its value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
dd23c9f1 |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around tp->tsoffset do_tcp_getsockopt() reads tp->tsoffset while another cpu might change its value. Fixes: 93be6ce0e91b ("tcp: set and get per-socket timestamp") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
348b81b6 |
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19-Jul-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races around tp->tcp_tx_delay do_tcp_getsockopt() reads tp->tcp_tx_delay while another cpu might change its value. Fixes: a842fe1425cb ("tcp: add optional per socket transmit delay") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230719212857.3943972-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
dc97391e |
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23-Jun-2023 |
David Howells <dhowells@redhat.com> |
sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES) Remove ->sendpage() and ->sendpage_locked(). sendmsg() with MSG_SPLICE_PAGES should be used instead. This allows multiple pages and multipage folios to be passed through. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> cc: linux-afs@lists.infradead.org cc: mptcp@lists.linux.dev cc: rds-devel@oss.oracle.com cc: tipc-discussion@lists.sourceforge.net cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
2fe11c9d |
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23-Jun-2023 |
Pavel Begunkov <asml.silence@gmail.com> |
net/tcp: optimise locking for blocking splice Even when tcp_splice_read() reads all it was asked for, for blocking sockets it'll release and immediately regrab the socket lock, loop around and break on the while check. Check tss.len right after we adjust it, and return if we're done. That saves us one release_sock(); lock_sock(); pair per successful blocking splice read. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/80736a2cc6d478c383ea565ba825eaf4d1abd876.1687523671.git.asml.silence@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
7a7f0946 |
|
16-Jun-2023 |
Arjun Roy <arjunroy@google.com> |
tcp: Use per-vma locking for receive zerocopy Per-VMA locking allows us to lock a struct vm_area_struct without taking the process-wide mmap lock in read mode. Consider a process workload where the mmap lock is taken constantly in write mode. In this scenario, all zerocopy receives are periodically blocked during that period of time - though in principle, the memory ranges being used by TCP are not touched by the operations that need the mmap write lock. This results in performance degradation. Now consider another workload where the mmap lock is never taken in write mode, but there are many TCP connections using receive zerocopy that are concurrently receiving. These connections all take the mmap lock in read mode, but this does induce a lot of contention and atomic ops for this process-wide lock. This results in additional CPU overhead caused by contending on the cache line for this lock. However, with per-vma locking, both of these problems can be avoided. As a test, I ran an RPC-style request/response workload with 4KB payloads and receive zerocopy enabled, with 100 simultaneous TCP connections. I measured perf cycles within the find_tcp_vma/mmap_read_lock/mmap_read_unlock codepath, with and without per-vma locking enabled. When using process-wide mmap semaphore read locking, about 1% of measured perf cycles were within this path. With per-VMA locking, this value dropped to about 0.45%. Signed-off-by: Arjun Roy <arjunroy@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e1d001fa |
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09-Jun-2023 |
Breno Leitao <leitao@debian.org> |
net: ioctl: Use kernel memory on protocol ioctl callbacks Most of the ioctls to net protocols operates directly on userspace argument (arg). Usually doing get_user()/put_user() directly in the ioctl callback. This is not flexible, because it is hard to reuse these functions without passing userspace buffers. Change the "struct proto" ioctls to avoid touching userspace memory and operate on kernel buffers, i.e., all protocol's ioctl callbacks is adapted to operate on a kernel memory other than on userspace (so, no more {put,get}_user() and friends being called in the ioctl callback). This changes the "struct proto" ioctl format in the following way: int (*ioctl)(struct sock *sk, int cmd, - unsigned long arg); + int *karg); (Important to say that this patch does not touch the "struct proto_ops" protocols) So, the "karg" argument, which is passed to the ioctl callback, is a pointer allocated to kernel space memory (inside a function wrapper). This buffer (karg) may contain input argument (copied from userspace in a prep function) and it might return a value/buffer, which is copied back to userspace if necessary. There is not one-size-fits-all format (that is I am using 'may' above), but basically, there are three type of ioctls: 1) Do not read from userspace, returns a result to userspace 2) Read an input parameter from userspace, and does not return anything to userspace 3) Read an input from userspace, and return a buffer to userspace. The default case (1) (where no input parameter is given, and an "int" is returned to userspace) encompasses more than 90% of the cases, but there are two other exceptions. Here is a list of exceptions: * Protocol RAW: * cmd = SIOCGETVIFCNT: * input and output = struct sioc_vif_req * cmd = SIOCGETSGCNT * input and output = struct sioc_sg_req * Explanation: for the SIOCGETVIFCNT case, userspace passes the input argument, which is struct sioc_vif_req. Then the callback populates the struct, which is copied back to userspace. * Protocol RAW6: * cmd = SIOCGETMIFCNT_IN6 * input and output = struct sioc_mif_req6 * cmd = SIOCGETSGCNT_IN6 * input and output = struct sioc_sg_req6 * Protocol PHONET: * cmd == SIOCPNADDRESOURCE | SIOCPNDELRESOURCE * input int (4 bytes) * Nothing is copied back to userspace. For the exception cases, functions sock_sk_ioctl_inout() will copy the userspace input, and copy it back to kernel space. The wrapper that prepare the buffer and put the buffer back to user is sk_ioctl(), so, instead of calling sk->sk_prot->ioctl(), the callee now calls sk_ioctl(), which will handle all cases. Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230609152800.830401-1-leitao@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
5882efff |
|
09-Jun-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: remove size parameter from tcp_stream_alloc_skb() Now all tcp_stream_alloc_skb() callers pass @size == 0, we can remove this parameter. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fbf93406 |
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09-Jun-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: let tcp_send_syn_data() build headless packets tcp_send_syn_data() is the last component in TCP transmit path to put payload in skb->head. Switch it to use page frags, so that we can remove dead code later. This allows to put more payload than previous implementation. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1d7e4538 |
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07-Jun-2023 |
David Howells <dhowells@redhat.com> |
ipv4, ipv6: Use splice_eof() to flush Allow splice to undo the effects of MSG_MORE after prematurely ending a splice/sendfile due to getting an EOF condition (->splice_read() returned 0) after splice had called sendmsg() with MSG_MORE set when the user didn't set MSG_MORE. For UDP, a pending packet will not be emitted if the socket is closed before it is flushed; with this change, it be flushed by ->splice_eof(). For TCP, it's not clear that MSG_MORE is actually effective. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/CAHk-=wh=V579PDYvkpnTobCLGczbgxpMgGmmhqiTyE34Cpi5Gg@mail.gmail.com/ Signed-off-by: David Howells <dhowells@redhat.com> cc: Kuniyuki Iwashima <kuniyu@amazon.com> cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com> cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
34dfde4a |
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26-May-2023 |
Cambda Zhu <cambda@linux.alibaba.com> |
tcp: Return user_mss for TCP_MAXSEG in CLOSE/LISTEN state if user_mss set This patch replaces the tp->mss_cache check in getting TCP_MAXSEG with tp->rx_opt.user_mss check for CLOSE/LISTEN sock. Since tp->mss_cache is initialized with TCP_MSS_DEFAULT, checking if it's zero is probably a bug. With this change, getting TCP_MAXSEG before connecting will return default MSS normally, and return user_mss if user_mss is set. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Jack Yang <mingliang@linux.alibaba.com> Suggested-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/netdev/CANn89i+3kL9pYtkxkwxwNMzvC_w3LNUum_2=3u+UyLBmGmifHA@mail.gmail.com/#t Signed-off-by: Cambda Zhu <cambda@linux.alibaba.com> Link: https://lore.kernel.org/netdev/14D45862-36EA-4076-974C-EA67513C92F6@linux.alibaba.com/ Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230527040317.68247-1-cambda@linux.alibaba.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
4faeee0c |
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26-May-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: deny tcp_disconnect() when threads are waiting Historically connect(AF_UNSPEC) has been abused by syzkaller and other fuzzers to trigger various bugs. A recent one triggers a divide-by-zero [1], and Paolo Abeni was able to diagnose the issue. tcp_recvmsg_locked() has tests about sk_state being not TCP_LISTEN and TCP REPAIR mode being not used. Then later if socket lock is released in sk_wait_data(), another thread can call connect(AF_UNSPEC), then make this socket a TCP listener. When recvmsg() is resumed, it can eventually call tcp_cleanup_rbuf() and attempt a divide by 0 in tcp_rcv_space_adjust() [1] This patch adds a new socket field, counting number of threads blocked in sk_wait_event() and inet_wait_for_connect(). If this counter is not zero, tcp_disconnect() returns an error. This patch adds code in blocking socket system calls, thus should not hurt performance of non blocking ones. Note that we probably could revert commit 499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead of 0") to restore original tcpi_rcv_mss meaning (was 0 if no payload was ever received on a socket) [1] divide error: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 13832 Comm: syz-executor.5 Not tainted 6.3.0-rc4-syzkaller-00224-g00c7b5f4ddc5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 RIP: 0010:tcp_rcv_space_adjust+0x36e/0x9d0 net/ipv4/tcp_input.c:740 Code: 00 00 00 00 fc ff df 4c 89 64 24 48 8b 44 24 04 44 89 f9 41 81 c7 80 03 00 00 c1 e1 04 44 29 f0 48 63 c9 48 01 e9 48 0f af c1 <49> f7 f6 48 8d 04 41 48 89 44 24 40 48 8b 44 24 30 48 c1 e8 03 48 RSP: 0018:ffffc900033af660 EFLAGS: 00010206 RAX: 4a66b76cbade2c48 RBX: ffff888076640cc0 RCX: 00000000c334e4ac RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 0000000000000001 RBP: 00000000c324e86c R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880766417f8 R13: ffff888028fbb980 R14: 0000000000000000 R15: 0000000000010344 FS: 00007f5bffbfe700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32f25000 CR3: 000000007ced0000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> tcp_recvmsg_locked+0x100e/0x22e0 net/ipv4/tcp.c:2616 tcp_recvmsg+0x117/0x620 net/ipv4/tcp.c:2681 inet6_recvmsg+0x114/0x640 net/ipv6/af_inet6.c:670 sock_recvmsg_nosec net/socket.c:1017 [inline] sock_recvmsg+0xe2/0x160 net/socket.c:1038 ____sys_recvmsg+0x210/0x5a0 net/socket.c:2720 ___sys_recvmsg+0xf2/0x180 net/socket.c:2762 do_recvmmsg+0x25e/0x6e0 net/socket.c:2856 __sys_recvmmsg net/socket.c:2935 [inline] __do_sys_recvmmsg net/socket.c:2958 [inline] __se_sys_recvmmsg net/socket.c:2951 [inline] __x64_sys_recvmmsg+0x20f/0x260 net/socket.c:2951 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f5c0108c0f9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5bffbfe168 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f5c011ac050 RCX: 00007f5c0108c0f9 RDX: 0000000000000001 RSI: 0000000020000bc0 RDI: 0000000000000003 RBP: 00007f5c010e7b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000122 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5c012cfb1f R14: 00007f5bffbfe300 R15: 0000000000022000 </TASK> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Reported-by: Paolo Abeni <pabeni@redhat.com> Diagnosed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20230526163458.2880232-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
5367f9bb |
|
22-May-2023 |
David Howells <dhowells@redhat.com> |
tcp: Fold do_tcp_sendpages() into tcp_sendpage_locked() Fold do_tcp_sendpages() into its last remaining caller, tcp_sendpage_locked(). Signed-off-by: David Howells <dhowells@redhat.com> cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
c5c37af6 |
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22-May-2023 |
David Howells <dhowells@redhat.com> |
tcp: Convert do_tcp_sendpages() to use MSG_SPLICE_PAGES Convert do_tcp_sendpages() to use sendmsg() with MSG_SPLICE_PAGES rather than directly splicing in the pages itself. do_tcp_sendpages() can then be inlined in subsequent patches into its callers. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells <dhowells@redhat.com> cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
270a1c3d |
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22-May-2023 |
David Howells <dhowells@redhat.com> |
tcp: Support MSG_SPLICE_PAGES Make TCP's sendmsg() support MSG_SPLICE_PAGES. This causes pages to be spliced or copied (if it cannot be spliced) from the source iterator. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells <dhowells@redhat.com> cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
e5c6de5f |
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22-May-2023 |
John Fastabend <john.fastabend@gmail.com> |
bpf, sockmap: Incorrectly handling copied_seq The read_skb() logic is incrementing the tcp->copied_seq which is used for among other things calculating how many outstanding bytes can be read by the application. This results in application errors, if the application does an ioctl(FIONREAD) we return zero because this is calculated from the copied_seq value. To fix this we move tcp->copied_seq accounting into the recv handler so that we update these when the recvmsg() hook is called and data is in fact copied into user buffers. This gives an accurate FIONREAD value as expected and improves ACK handling. Before we were calling the tcp_rcv_space_adjust() which would update 'number of bytes copied to user in last RTT' which is wrong for programs returning SK_PASS. The bytes are only copied to the user when recvmsg is handled. Doing the fix for recvmsg is straightforward, but fixing redirect and SK_DROP pkts is a bit tricker. Build a tcp_psock_eat() helper and then call this from skmsg handlers. This fixes another issue where a broken socket with a BPF program doing a resubmit could hang the receiver. This happened because although read_skb() consumed the skb through sock_drop() it did not update the copied_seq. Now if a single reccv socket is redirecting to many sockets (for example for lb) the receiver sk will be hung even though we might expect it to continue. The hang comes from not updating the copied_seq numbers and memory pressure resulting from that. We have a slight layer problem of calling tcp_eat_skb even if its not a TCP socket. To fix we could refactor and create per type receiver handlers. I decided this is more work than we want in the fix and we already have some small tweaks depending on caller that use the helper skb_bpf_strparser(). So we extend that a bit and always set the strparser bit when it is in use and then we can gate the seq_copied updates on this. Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230523025618.113937-9-john.fastabend@gmail.com
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#
78fa0d61 |
|
22-May-2023 |
John Fastabend <john.fastabend@gmail.com> |
bpf, sockmap: Pass skb ownership through read_skb The read_skb hook calls consume_skb() now, but this means that if the recv_actor program wants to use the skb it needs to inc the ref cnt so that the consume_skb() doesn't kfree the sk_buff. This is problematic because in some error cases under memory pressure we may need to linearize the sk_buff from sk_psock_skb_ingress_enqueue(). Then we get this, skb_linearize() __pskb_pull_tail() pskb_expand_head() BUG_ON(skb_shared(skb)) Because we incremented users refcnt from sk_psock_verdict_recv() we hit the bug on with refcnt > 1 and trip it. To fix lets simply pass ownership of the sk_buff through the skb_read call. Then we can drop the consume from read_skb handlers and assume the verdict recv does any required kfree. Bug found while testing in our CI which runs in VMs that hit memory constraints rather regularly. William tested TCP read_skb handlers. [ 106.536188] ------------[ cut here ]------------ [ 106.536197] kernel BUG at net/core/skbuff.c:1693! [ 106.536479] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 106.536726] CPU: 3 PID: 1495 Comm: curl Not tainted 5.19.0-rc5 #1 [ 106.537023] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.16.0-1 04/01/2014 [ 106.537467] RIP: 0010:pskb_expand_head+0x269/0x330 [ 106.538585] RSP: 0018:ffffc90000138b68 EFLAGS: 00010202 [ 106.538839] RAX: 000000000000003f RBX: ffff8881048940e8 RCX: 0000000000000a20 [ 106.539186] RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff8881048940e8 [ 106.539529] RBP: ffffc90000138be8 R08: 00000000e161fd1a R09: 0000000000000000 [ 106.539877] R10: 0000000000000018 R11: 0000000000000000 R12: ffff8881048940e8 [ 106.540222] R13: 0000000000000003 R14: 0000000000000000 R15: ffff8881048940e8 [ 106.540568] FS: 00007f277dde9f00(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000 [ 106.540954] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 106.541227] CR2: 00007f277eeede64 CR3: 000000000ad3e000 CR4: 00000000000006e0 [ 106.541569] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 106.541915] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 106.542255] Call Trace: [ 106.542383] <IRQ> [ 106.542487] __pskb_pull_tail+0x4b/0x3e0 [ 106.542681] skb_ensure_writable+0x85/0xa0 [ 106.542882] sk_skb_pull_data+0x18/0x20 [ 106.543084] bpf_prog_b517a65a242018b0_bpf_skskb_http_verdict+0x3a9/0x4aa9 [ 106.543536] ? migrate_disable+0x66/0x80 [ 106.543871] sk_psock_verdict_recv+0xe2/0x310 [ 106.544258] ? sk_psock_write_space+0x1f0/0x1f0 [ 106.544561] tcp_read_skb+0x7b/0x120 [ 106.544740] tcp_data_queue+0x904/0xee0 [ 106.544931] tcp_rcv_established+0x212/0x7c0 [ 106.545142] tcp_v4_do_rcv+0x174/0x2a0 [ 106.545326] tcp_v4_rcv+0xe70/0xf60 [ 106.545500] ip_protocol_deliver_rcu+0x48/0x290 [ 106.545744] ip_local_deliver_finish+0xa7/0x150 Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()") Reported-by: William Findlay <will@isovalent.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: William Findlay <will@isovalent.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230523025618.113937-2-john.fastabend@gmail.com
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#
4ddbcb88 |
|
19-May-2023 |
Aditi Ghag <aditi.ghag@isovalent.com> |
bpf: Add bpf_sock_destroy kfunc The socket destroy kfunc is used to forcefully terminate sockets from certain BPF contexts. We plan to use the capability in Cilium load-balancing to terminate client sockets that continue to connect to deleted backends. The other use case is on-the-fly policy enforcement where existing socket connections prevented by policies need to be forcefully terminated. The kfunc also allows terminating sockets that may or may not be actively sending traffic. The kfunc can currently be called only from BPF TCP and UDP iterators where users can filter, and terminate selected sockets. More specifically, it can only be called from BPF contexts that ensure socket locking in order to allow synchronous execution of protocol specific `diag_destroy` handlers. The previous commit that batches UDP sockets during iteration facilitated a synchronous invocation of the UDP destroy callback from BPF context by skipping socket locks in `udp_abort`. TCP iterator already supported batching of sockets being iterated. To that end, `tracing_iter_filter` callback filter is added so that verifier can restrict the kfunc to programs with `BPF_TRACE_ITER` attach type, and reject other programs. The kfunc takes `sock_common` type argument, even though it expects, and casts them to a `sock` pointer. This enables the verifier to allow the sock_destroy kfunc to be called for TCP with `sock_common` and UDP with `sock` structs. Furthermore, as `sock_common` only has a subset of certain fields of `sock`, casting pointer to the latter type might not always be safe for certain sockets like request sockets, but these have a special handling in the diag_destroy handlers. Additionally, the kfunc is defined with `KF_TRUSTED_ARGS` flag to avoid the cases where a `PTR_TO_BTF_ID` sk is obtained by following another pointer. eg. getting a sk pointer (may be even NULL) by following another sk pointer. The pointer socket argument passed in TCP and UDP iterators is tagged as `PTR_TRUSTED` in {tcp,udp}_reg_info. The TRUSTED arg changes are contributed by Martin KaFai Lau <martin.lau@kernel.org>. Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20230519225157.760788-8-aditi.ghag@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
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#
a7533584 |
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15-May-2023 |
Pavel Begunkov <asml.silence@gmail.com> |
net/tcp: optimise io_uring zc ubuf refcounting io_uring keeps a reference to ubuf_info during submission, so if tcp_sendmsg_locked() sees msghdr::msg_ubuf in can be sure the buffer will be kept alive and doesn't need to additionally pin it. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
eea96a3e |
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15-May-2023 |
Pavel Begunkov <asml.silence@gmail.com> |
net/tcp: don't peek at tail for io_uring zc Move tcp_write_queue_tail() to SOCK_ZEROCOPY specific flag as zerocopy setup for msghdr->ubuf_info doesn't need to peek into the last request. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e14cadfd |
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09-May-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: add annotations around sk->sk_shutdown accesses Now sk->sk_shutdown is no longer a bitfield, we can add standard READ_ONCE()/WRITE_ONCE() annotations to silence KCSAN reports like the following: BUG: KCSAN: data-race in tcp_disconnect / tcp_poll write to 0xffff88814588582c of 1 bytes by task 3404 on cpu 1: tcp_disconnect+0x4d6/0xdb0 net/ipv4/tcp.c:3121 __inet_stream_connect+0x5dd/0x6e0 net/ipv4/af_inet.c:715 inet_stream_connect+0x48/0x70 net/ipv4/af_inet.c:727 __sys_connect_file net/socket.c:2001 [inline] __sys_connect+0x19b/0x1b0 net/socket.c:2018 __do_sys_connect net/socket.c:2028 [inline] __se_sys_connect net/socket.c:2025 [inline] __x64_sys_connect+0x41/0x50 net/socket.c:2025 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff88814588582c of 1 bytes by task 3374 on cpu 0: tcp_poll+0x2e6/0x7d0 net/ipv4/tcp.c:562 sock_poll+0x253/0x270 net/socket.c:1383 vfs_poll include/linux/poll.h:88 [inline] io_poll_check_events io_uring/poll.c:281 [inline] io_poll_task_func+0x15a/0x820 io_uring/poll.c:333 handle_tw_list io_uring/io_uring.c:1184 [inline] tctx_task_work+0x1fe/0x4d0 io_uring/io_uring.c:1246 task_work_run+0x123/0x160 kernel/task_work.c:179 get_signal+0xe64/0xff0 kernel/signal.c:2635 arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x03 -> 0x00 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c39ef213 |
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12-Apr-2023 |
Kevin Brodsky <kevin.brodsky@arm.com> |
net: Ensure ->msg_control_user is used for user buffers Since commit 1f466e1f15cf ("net: cleanly handle kernel vs user buffers for ->msg_control"), pointers to user buffers should be stored in struct msghdr::msg_control_user, instead of the msg_control field. Most users of msg_control have already been converted (where user buffers are involved), but not all of them. This patch attempts to address the remaining cases. An exception is made for null checks, as it should be safe to use msg_control unconditionally for that purpose. Cc: Christoph Hellwig <hch@lst.de> Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e9d9da91 |
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17-Mar-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: preserve const qualifier in tcp_sk() We can change tcp_sk() to propagate its argument const qualifier, thanks to container_of_const(). We have two places where a const sock pointer has to be upgraded to a write one. We have been using const qualifier for lockless listeners to clearly identify points where writes could happen. Add tcp_sk_rw() helper to better document these. tcp_inbound_md5_hash(), __tcp_grow_window(), tcp_reset_check() and tcp_rack_reo_wnd() get an additional const qualififer for their @tp local variables. smc_check_reset_syn_req() also needs a similar change. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e13ec3da |
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15-Mar-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate lockless access to sk->sk_err tcp_poll() reads sk->sk_err without socket lock held/owned. We should used READ_ONCE() here, and update writers to use WRITE_ONCE(). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1c71222e |
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26-Jan-2023 |
Suren Baghdasaryan <surenb@google.com> |
mm: replace vma->vm_flags direct modifications with modifier calls Replace direct modifications to vma->vm_flags with calls to modifier functions to be able to track flag changes and to keep vma locking correctness. [akpm@linux-foundation.org: fix drivers/misc/open-dice.c, per Hyeonggon Yoo] Link: https://lkml.kernel.org/r/20230126193752.297968-5-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjun Roy <arjunroy@google.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: David Rientjes <rientjes@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Thelen <gthelen@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Joel Fernandes <joelaf@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Minchan Kim <minchan@google.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Peter Oskolkov <posk@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Punit Agrawal <punit.agrawal@bytedance.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Shakeel Butt <shakeelb@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Song Liu <songliubraving@fb.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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#
e9adcfec |
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03-Jan-2023 |
Mike Kravetz <mike.kravetz@oracle.com> |
mm: remove zap_page_range and create zap_vma_pages zap_page_range was originally designed to unmap pages within an address range that could span multiple vmas. While working on [1], it was discovered that all callers of zap_page_range pass a range entirely within a single vma. In addition, the mmu notification call within zap_page range does not correctly handle ranges that span multiple vmas. When crossing a vma boundary, a new mmu_notifier_range_init/end call pair with the new vma should be made. Instead of fixing zap_page_range, do the following: - Create a new routine zap_vma_pages() that will remove all pages within the passed vma. Most users of zap_page_range pass the entire vma and can use this new routine. - For callers of zap_page_range not passing the entire vma, instead call zap_page_range_single(). - Remove zap_page_range. [1] https://lore.kernel.org/linux-mm/20221114235507.294320-2-mike.kravetz@oracle.com/ Link: https://lkml.kernel.org/r/20230104002732.232573-1-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Suggested-by: Peter Xu <peterx@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Peter Xu <peterx@redhat.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> [s390] Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Rik van Riel <riel@surriel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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#
300b655d |
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19-Jan-2023 |
David Morley <morleyd@google.com> |
tcp: fix rate_app_limited to default to 1 The initial default value of 0 for tp->rate_app_limited was incorrect, since a flow is indeed application-limited until it first sends data. Fixing the default to be 1 is generally correct but also specifically will help user-space applications avoid using the initial tcpi_delivery_rate value of 0 that persists until the connection has some non-zero bandwidth sample. Fixes: eb8329e0a04d ("tcp: export data delivery rate") Suggested-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David Morley <morleyd@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Tested-by: David Morley <morleyd@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
459837b5 |
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23-Nov-2022 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Disable TCP-MD5 static key on tcp_md5sig_info destruction To do that, separate two scenarios: - where it's the first MD5 key on the system, which means that enabling of the static key may need to sleep; - copying of an existing key from a listening socket to the request socket upon receiving a signed TCP segment, where static key was already enabled (when the key was added to the listening socket). Now the life-time of the static branch for TCP-MD5 is until: - last tcp_md5sig_info is destroyed - last socket in time-wait state with MD5 key is closed. Which means that after all sockets with TCP-MD5 keys are gone, the system gets back the performance of disabled md5-key static branch. While at here, provide static_key_fast_inc() helper that does ref counter increment in atomic fashion (without grabbing cpus_read_lock() on CONFIG_JUMP_LABEL=y). This is needed to add a new user for a static_key when the caller controls the lifetime of another user. Signed-off-by: Dmitry Safonov <dima@arista.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
de4eda9d |
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15-Sep-2022 |
Al Viro <viro@zeniv.linux.org.uk> |
use less confusing names for iov_iter direction initializers READ/WRITE proved to be actively confusing - the meanings are "data destination, as used with read(2)" and "data source, as used with write(2)", but people keep interpreting those as "we read data from it" and "we write data to it", i.e. exactly the wrong way. Call them ITER_DEST and ITER_SOURCE - at least that is harder to misinterpret... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
71fc7047 |
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26-Oct-2022 |
Mubashir Adnan Qureshi <mubashirq@google.com> |
tcp: add rcv_wnd and plb_rehash to TCP_INFO rcv_wnd can be useful to diagnose TCP performance where receiver window becomes the bottleneck. rehash reports the PLB and timeout triggered rehash attempts by the TCP connection. Signed-off-by: Mubashir Adnan Qureshi <mubashirq@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
29c1c446 |
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26-Oct-2022 |
Mubashir Adnan Qureshi <mubashirq@google.com> |
tcp: add u32 counter in tcp_sock and an SNMP counter for PLB A u32 counter is added to tcp_sock for counting the number of PLB triggered rehashes for a TCP connection. An SNMP counter is also added to count overall PLB triggered rehash events for a host. These counters are hooked up to PLB implementation for DCTCP. TCP_NLA_REHASH is added to SCM_TIMESTAMPING_OPT_STATS that reports the rehash attempts triggered due to PLB or timeouts. This gives a historical view of sustained congestion or timeouts experienced by the TCP connection. Signed-off-by: Mubashir Adnan Qureshi <mubashirq@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e0833d1f |
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18-Nov-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
dccp/tcp: Fixup bhash2 bucket when connect() fails. If a socket bound to a wildcard address fails to connect(), we only reset saddr and keep the port. Then, we have to fix up the bhash2 bucket; otherwise, the bucket has an inconsistent address in the list. Also, listen() for such a socket will fire the WARN_ON() in inet_csk_get_port(). [0] Note that when a system runs out of memory, we give up fixing the bucket and unlink sk from bhash and bhash2 by inet_put_port(). [0]: WARNING: CPU: 0 PID: 207 at net/ipv4/inet_connection_sock.c:548 inet_csk_get_port (net/ipv4/inet_connection_sock.c:548 (discriminator 1)) Modules linked in: CPU: 0 PID: 207 Comm: bhash2_prev_rep Not tainted 6.1.0-rc3-00799-gc8421681c845 #63 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.amzn2022.0.1 04/01/2014 RIP: 0010:inet_csk_get_port (net/ipv4/inet_connection_sock.c:548 (discriminator 1)) Code: 74 a7 eb 93 48 8b 54 24 18 0f b7 cb 4c 89 e6 4c 89 ff e8 48 b2 ff ff 49 8b 87 18 04 00 00 e9 32 ff ff ff 0f 0b e9 34 ff ff ff <0f> 0b e9 42 ff ff ff 41 8b 7f 50 41 8b 4f 54 89 fe 81 f6 00 00 ff RSP: 0018:ffffc900003d7e50 EFLAGS: 00010202 RAX: ffff8881047fb500 RBX: 0000000000004e20 RCX: 0000000000000000 RDX: 000000000000000a RSI: 00000000fffffe00 RDI: 00000000ffffffff RBP: ffffffff8324dc00 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000004e20 R15: ffff8881054e1280 FS: 00007f8ac04dc740(0000) GS:ffff88842fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020001540 CR3: 00000001055fa003 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> inet_csk_listen_start (net/ipv4/inet_connection_sock.c:1205) inet_listen (net/ipv4/af_inet.c:228) __sys_listen (net/socket.c:1810) __x64_sys_listen (net/socket.c:1819 net/socket.c:1817 net/socket.c:1817) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) RIP: 0033:0x7f8ac051de5d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 93 af 1b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffc1c177248 EFLAGS: 00000206 ORIG_RAX: 0000000000000032 RAX: ffffffffffffffda RBX: 0000000020001550 RCX: 00007f8ac051de5d RDX: ffffffffffffff80 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007ffc1c177270 R08: 0000000000000018 R09: 0000000000000007 R10: 0000000020001540 R11: 0000000000000206 R12: 00007ffc1c177388 R13: 0000000000401169 R14: 0000000000403e18 R15: 00007f8ac0723000 </TASK> Fixes: 28044fc1d495 ("net: Add a bhash2 table hashed by port and address") Reported-by: syzbot <syzkaller@googlegroups.com> Reported-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
0c175da7 |
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03-Nov-2022 |
Lu Wei <luwei32@huawei.com> |
tcp: prohibit TCP_REPAIR_OPTIONS if data was already sent If setsockopt with option name of TCP_REPAIR_OPTIONS and opt_code of TCPOPT_SACK_PERM is called to enable sack after data is sent and dupacks are received , it will trigger a warning in function tcp_verify_left_out() as follows: ============================================ WARNING: CPU: 8 PID: 0 at net/ipv4/tcp_input.c:2132 tcp_timeout_mark_lost+0x154/0x160 tcp_enter_loss+0x2b/0x290 tcp_retransmit_timer+0x50b/0x640 tcp_write_timer_handler+0x1c8/0x340 tcp_write_timer+0xe5/0x140 call_timer_fn+0x3a/0x1b0 __run_timers.part.0+0x1bf/0x2d0 run_timer_softirq+0x43/0xb0 __do_softirq+0xfd/0x373 __irq_exit_rcu+0xf6/0x140 The warning is caused in the following steps: 1. a socket named socketA is created 2. socketA enters repair mode without build a connection 3. socketA calls connect() and its state is changed to TCP_ESTABLISHED directly 4. socketA leaves repair mode 5. socketA calls sendmsg() to send data, packets_out and sack_outs(dup ack receives) increase 6. socketA enters repair mode again 7. socketA calls setsockopt with TCPOPT_SACK_PERM to enable sack 8. retransmit timer expires, it calls tcp_timeout_mark_lost(), lost_out increases 9. sack_outs + lost_out > packets_out triggers since lost_out and sack_outs increase repeatly In function tcp_timeout_mark_lost(), tp->sacked_out will be cleared if Step7 not happen and the warning will not be triggered. As suggested by Denis and Eric, TCP_REPAIR_OPTIONS should be prohibited if data was already sent. socket-tcp tests in CRIU has been tested as follows: $ sudo ./test/zdtm.py run -t zdtm/static/socket-tcp* --keep-going \ --ignore-taint socket-tcp* represent all socket-tcp tests in test/zdtm/static/. Fixes: b139ba4e90dc ("tcp: Repair connection-time negotiated parameters") Signed-off-by: Lu Wei <luwei32@huawei.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e993ffe3 |
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21-Oct-2022 |
Pavel Begunkov <asml.silence@gmail.com> |
net: flag sockets supporting msghdr originated zerocopy We need an efficient way in io_uring to check whether a socket supports zerocopy with msghdr provided ubuf_info. Add a new flag into the struct socket flags fields. Cc: <stable@vger.kernel.org> # 6.0 Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/3dafafab822b1c66308bb58a0ac738b1e3f53f74.1666346426.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
f49cd2f4 |
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06-Oct-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix data races around icsk->icsk_af_ops. setsockopt(IPV6_ADDRFORM) and tcp_v6_connect() change icsk->icsk_af_ops under lock_sock(), but tcp_(get|set)sockopt() read it locklessly. To avoid load/store tearing, we need to add READ_ONCE() and WRITE_ONCE() for the reads and writes. Thanks to Eric Dumazet for providing the syzbot report: BUG: KCSAN: data-race in tcp_setsockopt / tcp_v6_connect write to 0xffff88813c624518 of 8 bytes by task 23936 on cpu 0: tcp_v6_connect+0x5b3/0xce0 net/ipv6/tcp_ipv6.c:240 __inet_stream_connect+0x159/0x6d0 net/ipv4/af_inet.c:660 inet_stream_connect+0x44/0x70 net/ipv4/af_inet.c:724 __sys_connect_file net/socket.c:1976 [inline] __sys_connect+0x197/0x1b0 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __x64_sys_connect+0x3d/0x50 net/socket.c:2000 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff88813c624518 of 8 bytes by task 23937 on cpu 1: tcp_setsockopt+0x147/0x1c80 net/ipv4/tcp.c:3789 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3585 __sys_setsockopt+0x212/0x2b0 net/socket.c:2252 __do_sys_setsockopt net/socket.c:2263 [inline] __se_sys_setsockopt net/socket.c:2260 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2260 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0xffffffff8539af68 -> 0xffffffff8539aff8 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 23937 Comm: syz-executor.5 Not tainted 6.0.0-rc4-syzkaller-00331-g4ed9c1e971b1-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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f4ce91ce |
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28-Sep-2022 |
Neal Cardwell <ncardwell@google.com> |
tcp: fix tcp_cwnd_validate() to not forget is_cwnd_limited This commit fixes a bug in the tracking of max_packets_out and is_cwnd_limited. This bug can cause the connection to fail to remember that is_cwnd_limited is true, causing the connection to fail to grow cwnd when it should, causing throughput to be lower than it should be. The following event sequence is an example that triggers the bug: (a) The connection is cwnd_limited, but packets_out is not at its peak due to TSO deferral deciding not to send another skb yet. In such cases the connection can advance max_packets_seq and set tp->is_cwnd_limited to true and max_packets_out to a small number. (b) Then later in the round trip the connection is pacing-limited (not cwnd-limited), and packets_out is larger. In such cases the connection would raise max_packets_out to a bigger number but (unexpectedly) flip tp->is_cwnd_limited from true to false. This commit fixes that bug. One straightforward fix would be to separately track (a) the next window after max_packets_out reaches a maximum, and (b) the next window after tp->is_cwnd_limited is set to true. But this would require consuming an extra u32 sequence number. Instead, to save space we track only the most important information. Specifically, we track the strongest available signal of the degree to which the cwnd is fully utilized: (1) If the connection is cwnd-limited then we remember that fact for the current window. (2) If the connection not cwnd-limited then we track the maximum number of outstanding packets in the current window. In particular, note that the new logic cannot trigger the buggy (a)/(b) sequence above because with the new logic a condition where tp->packets_out > tp->max_packets_out can only trigger an update of tp->is_cwnd_limited if tp->is_cwnd_limited is false. This first showed up in a testing of a BBRv2 dev branch, but this buggy behavior highlighted a general issue with the tcp_cwnd_validate() logic that can cause cwnd to fail to increase at the proper rate for any TCP congestion control, including Reno or CUBIC. Fixes: ca8a22634381 ("tcp: make cwnd-limited checks measurement-based, and gentler") Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Kevin(Yudong) Yang <yyd@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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3242abeb |
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26-Sep-2022 |
Benjamin Hesmans <benjamin.hesmans@tessares.net> |
tcp: export tcp_sendmsg_fastopen It will be used to support TCP FastOpen with MPTCP in the following commit. Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Co-developed-by: Dmytro Shytyi <dmytro@shytyi.net> Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net> Signed-off-by: Benjamin Hesmans <benjamin.hesmans@tessares.net> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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e7d2b510 |
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23-Sep-2022 |
Pavel Begunkov <asml.silence@gmail.com> |
net: shrink struct ubuf_info We can benefit from a smaller struct ubuf_info, so leave only mandatory fields and let users to decide how they want to extend it. Convert MSG_ZEROCOPY to struct ubuf_info_msgzc and remove duplicated fields. This reduces the size from 48 bytes to just 16. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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d1e5e640 |
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07-Sep-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Introduce optional per-netns ehash. The more sockets we have in the hash table, the longer we spend looking up the socket. While running a number of small workloads on the same host, they penalise each other and cause performance degradation. The root cause might be a single workload that consumes much more resources than the others. It often happens on a cloud service where different workloads share the same computing resource. On EC2 c5.24xlarge instance (196 GiB memory and 524288 (1Mi / 2) ehash entries), after running iperf3 in different netns, creating 24Mi sockets without data transfer in the root netns causes about 10% performance regression for the iperf3's connection. thash_entries sockets length Gbps 524288 1 1 50.7 24Mi 48 45.1 It is basically related to the length of the list of each hash bucket. For testing purposes to see how performance drops along the length, I set 131072 (1Mi / 8) to thash_entries, and here's the result. thash_entries sockets length Gbps 131072 1 1 50.7 1Mi 8 49.9 2Mi 16 48.9 4Mi 32 47.3 8Mi 64 44.6 16Mi 128 40.6 24Mi 192 36.3 32Mi 256 32.5 40Mi 320 27.0 48Mi 384 25.0 To resolve the socket lookup degradation, we introduce an optional per-netns hash table for TCP, but it's just ehash, and we still share the global bhash, bhash2 and lhash2. With a smaller ehash, we can look up non-listener sockets faster and isolate such noisy neighbours. In addition, we can reduce lock contention. We can control the ehash size by a new sysctl knob. However, depending on workloads, it will require very sensitive tuning, so we disable the feature by default (net.ipv4.tcp_child_ehash_entries == 0). Moreover, we can fall back to using the global ehash in case we fail to allocate enough memory for a new ehash. The maximum size is 16Mi, which is large enough that even if we have 48Mi sockets, the average list length is 3, and regression would be less than 1%. We can check the current ehash size by another read-only sysctl knob, net.ipv4.tcp_ehash_entries. A negative value means the netns shares the global ehash (per-netns ehash is disabled or failed to allocate memory). # dmesg | cut -d ' ' -f 5- | grep "established hash" TCP established hash table entries: 524288 (order: 10, 4194304 bytes, vmalloc hugepage) # sysctl net.ipv4.tcp_ehash_entries net.ipv4.tcp_ehash_entries = 524288 # can be changed by thash_entries # sysctl net.ipv4.tcp_child_ehash_entries net.ipv4.tcp_child_ehash_entries = 0 # disabled by default # ip netns add test1 # ip netns exec test1 sysctl net.ipv4.tcp_ehash_entries net.ipv4.tcp_ehash_entries = -524288 # share the global ehash # sysctl -w net.ipv4.tcp_child_ehash_entries=100 net.ipv4.tcp_child_ehash_entries = 100 # ip netns add test2 # ip netns exec test2 sysctl net.ipv4.tcp_ehash_entries net.ipv4.tcp_ehash_entries = 128 # own a per-netns ehash with 2^n buckets When more than two processes in the same netns create per-netns ehash concurrently with different sizes, we need to guarantee the size in one of the following ways: 1) Share the global ehash and create per-netns ehash First, unshare() with tcp_child_ehash_entries==0. It creates dedicated netns sysctl knobs where we can safely change tcp_child_ehash_entries and clone()/unshare() to create a per-netns ehash. 2) Control write on sysctl by BPF We can use BPF_PROG_TYPE_CGROUP_SYSCTL to allow/deny read/write on sysctl knobs. Note that the global ehash allocated at the boot time is spread over available NUMA nodes, but inet_pernet_hashinfo_alloc() will allocate pages for each per-netns ehash depending on the current process's NUMA policy. By default, the allocation is done in the local node only, so the per-netns hash table could fully reside on a random node. Thus, depending on the NUMA policy the netns is created with and the CPU the current thread is running on, we could see some performance differences for highly optimised networking applications. Note also that the default values of two sysctl knobs depend on the ehash size and should be tuned carefully: tcp_max_tw_buckets : tcp_child_ehash_entries / 2 tcp_max_syn_backlog : max(128, tcp_child_ehash_entries / 128) As a bonus, we can dismantle netns faster. Currently, while destroying netns, we call inet_twsk_purge(), which walks through the global ehash. It can be potentially big because it can have many sockets other than TIME_WAIT in all netns. Splitting ehash changes that situation, where it's only necessary for inet_twsk_purge() to clean up TIME_WAIT sockets in each netns. With regard to this, we do not free the per-netns ehash in inet_twsk_kill() to avoid UAF while iterating the per-netns ehash in inet_twsk_purge(). Instead, we do it in tcp_sk_exit_batch() after calling tcp_twsk_purge() to keep it protocol-family-independent. In the future, we could optimise ehash lookup/iteration further by removing netns comparison for the per-netns ehash. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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273b7f0f |
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01-Sep-2022 |
Martin KaFai Lau <martin.lau@kernel.org> |
bpf: Change bpf_getsockopt(SOL_TCP) to reuse do_tcp_getsockopt() This patch changes bpf_getsockopt(SOL_TCP) to reuse do_tcp_getsockopt(). It removes the duplicated code from bpf_getsockopt(SOL_TCP). Before this patch, there were some optnames available to bpf_setsockopt(SOL_TCP) but missing in bpf_getsockopt(SOL_TCP). For example, TCP_NODELAY, TCP_MAXSEG, TCP_KEEPIDLE, TCP_KEEPINTVL, and a few more. It surprises users from time to time. This patch automatically closes this gap without duplicating more code. bpf_getsockopt(TCP_SAVED_SYN) does not free the saved_syn, so it stays in sol_tcp_sockopt(). For string name value like TCP_CONGESTION, bpf expects it is always null terminated, so sol_tcp_sockopt() decrements optlen by one before calling do_tcp_getsockopt() and the 'if (optlen < saved_optlen) memset(..,0,..);' in __bpf_getsockopt() will always do a null termination. Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20220902002918.2894511-1-kafai@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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d51bbff2 |
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01-Sep-2022 |
Martin KaFai Lau <martin.lau@kernel.org> |
bpf: net: Avoid do_tcp_getsockopt() taking sk lock when called from bpf Similar to the earlier commit that changed sk_setsockopt() to use sockopt_{lock,release}_sock() such that it can avoid taking lock when called from bpf. This patch also changes do_tcp_getsockopt() to use sockopt_{lock,release}_sock() such that a latter patch can make bpf_getsockopt(SOL_TCP) to reuse do_tcp_getsockopt(). Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20220902002821.2889765-1-kafai@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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34704ef0 |
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01-Sep-2022 |
Martin KaFai Lau <martin.lau@kernel.org> |
bpf: net: Change do_tcp_getsockopt() to take the sockptr_t argument Similar to the earlier patch that changes sk_getsockopt() to take the sockptr_t argument . This patch also changes do_tcp_getsockopt() to take the sockptr_t argument such that a latter patch can make bpf_getsockopt(SOL_TCP) to reuse do_tcp_getsockopt(). Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20220902002815.2889332-1-kafai@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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84e5a0f2 |
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30-Aug-2022 |
Martin KaFai Lau <martin.lau@linux.dev> |
bpf, net: Avoid loading module when calling bpf_setsockopt(TCP_CONGESTION) When bpf prog changes tcp-cc by calling bpf_setsockopt(TCP_CONGESTION), it should not try to load module which may be a blocking operation. This details was correct in the v1 [0] but missed by mistake in the later revision in commit cb388e7ee3a8 ("bpf: net: Change do_tcp_setsockopt() to use the sockopt's lock_sock() and capable()"). This patch fixes it by checking the has_current_bpf_ctx(). [0] https://lore.kernel.org/bpf/20220727060921.2373314-1-kafai@fb.com/ Fixes: cb388e7ee3a8 ("bpf: net: Change do_tcp_setsockopt() to use the sockopt's lock_sock() and capable()") Signed-off-by: Martin KaFai Lau <martin.lau@linux.dev> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220830231946.791504-1-martin.lau@linux.dev
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28044fc1 |
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22-Aug-2022 |
Joanne Koong <joannelkoong@gmail.com> |
net: Add a bhash2 table hashed by port and address The current bind hashtable (bhash) is hashed by port only. In the socket bind path, we have to check for bind conflicts by traversing the specified port's inet_bind_bucket while holding the hashbucket's spinlock (see inet_csk_get_port() and inet_csk_bind_conflict()). In instances where there are tons of sockets hashed to the same port at different addresses, the bind conflict check is time-intensive and can cause softirq cpu lockups, as well as stops new tcp connections since __inet_inherit_port() also contests for the spinlock. This patch adds a second bind table, bhash2, that hashes by port and sk->sk_rcv_saddr (ipv4) and sk->sk_v6_rcv_saddr (ipv6). Searching the bhash2 table leads to significantly faster conflict resolution and less time holding the hashbucket spinlock. Please note a few things: * There can be the case where the a socket's address changes after it has been bound. There are two cases where this happens: 1) The case where there is a bind() call on INADDR_ANY (ipv4) or IPV6_ADDR_ANY (ipv6) and then a connect() call. The kernel will assign the socket an address when it handles the connect() 2) In inet_sk_reselect_saddr(), which is called when rebuilding the sk header and a few pre-conditions are met (eg rerouting fails). In these two cases, we need to update the bhash2 table by removing the entry for the old address, and add a new entry reflecting the updated address. * The bhash2 table must have its own lock, even though concurrent accesses on the same port are protected by the bhash lock. Bhash2 must have its own lock to protect against cases where sockets on different ports hash to different bhash hashbuckets but to the same bhash2 hashbucket. This brings up a few stipulations: 1) When acquiring both the bhash and the bhash2 lock, the bhash2 lock will always be acquired after the bhash lock and released before the bhash lock is released. 2) There are no nested bhash2 hashbucket locks. A bhash2 lock is always acquired+released before another bhash2 lock is acquired+released. * The bhash table cannot be superseded by the bhash2 table because for bind requests on INADDR_ANY (ipv4) or IPV6_ADDR_ANY (ipv6), every socket bound to that port must be checked for a potential conflict. The bhash table is the only source of port->socket associations. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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aacd467c |
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22-Aug-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-race around tcp_md5sig_pool_populated tcp_md5sig_pool_populated can be read while another thread changes its value. The race has no consequence because allocations are protected with tcp_md5sig_mutex. This patch adds READ_ONCE() and WRITE_ONCE() to document the race and silence KCSAN. Reported-by: Abhishek Shah <abhishek.shah@columbia.edu> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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0c751f70 |
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17-Aug-2022 |
Martin KaFai Lau <kafai@fb.com> |
bpf: Change bpf_setsockopt(SOL_TCP) to reuse do_tcp_setsockopt() After the prep work in the previous patches, this patch removes all the dup code from bpf_setsockopt(SOL_TCP) and reuses the do_tcp_setsockopt(). The existing optname white-list is refactored into a new function sol_tcp_setsockopt(). The sol_tcp_setsockopt() also calls the bpf_sol_tcp_setsockopt() to handle the TCP_BPF_XXX specific optnames. bpf_setsockopt(TCP_SAVE_SYN) now also allows a value 2 to save the eth header also and it comes for free from do_tcp_setsockopt(). Reviewed-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/r/20220817061819.4180146-1-kafai@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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cb388e7e |
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17-Aug-2022 |
Martin KaFai Lau <kafai@fb.com> |
bpf: net: Change do_tcp_setsockopt() to use the sockopt's lock_sock() and capable() Similar to the earlier patch that avoids sk_setsockopt() from taking sk lock and doing capable test when called by bpf. This patch changes do_tcp_setsockopt() to use the sockopt_{lock,release}_sock() and sockopt_[ns_]capable(). Reviewed-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/r/20220817061730.4176021-1-kafai@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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db4192a7 |
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12-Sep-2022 |
Cong Wang <cong.wang@bytedance.com> |
tcp: read multiple skbs in tcp_read_skb() Before we switched to ->read_skb(), ->read_sock() was passed with desc.count=1, which technically indicates we only read one skb per ->sk_data_ready() call. However, for TCP, this is not true. TCP at least has sk_rcvlowat which intentionally holds skb's in receive queue until this watermark is reached. This means when ->sk_data_ready() is invoked there could be multiple skb's in the queue, therefore we have to read multiple skbs in tcp_read_skb() instead of one. Fixes: 965b57b469a5 ("net: Introduce a new proto_ops ->read_skb()") Reported-by: Peilin Ye <peilin.ye@bytedance.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jakub Sitnicki <jakub@cloudflare.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Link: https://lore.kernel.org/r/20220912173553.235838-1-xiyou.wangcong@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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96628951 |
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08-Sep-2022 |
Peilin Ye <peilin.ye@bytedance.com> |
tcp: Use WARN_ON_ONCE() in tcp_read_skb() Prevent tcp_read_skb() from flooding the syslog. Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Peilin Ye <peilin.ye@bytedance.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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32614006 |
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31-Aug-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: TX zerocopy should not sense pfmemalloc status We got a recent syzbot report [1] showing a possible misuse of pfmemalloc page status in TCP zerocopy paths. Indeed, for pages coming from user space or other layers, using page_is_pfmemalloc() is moot, and possibly could give false positives. There has been attempts to make page_is_pfmemalloc() more robust, but not using it in the first place in this context is probably better, removing cpu cycles. Note to stable teams : You need to backport 84ce071e38a6 ("net: introduce __skb_fill_page_desc_noacc") as a prereq. Race is more probable after commit c07aea3ef4d4 ("mm: add a signature in struct page") because page_is_pfmemalloc() is now using low order bit from page->lru.next, which can change more often than page->index. Low order bit should never be set for lru.next (when used as an anchor in LRU list), so KCSAN report is mostly a false positive. Backporting to older kernel versions seems not necessary. [1] BUG: KCSAN: data-race in lru_add_fn / tcp_build_frag write to 0xffffea0004a1d2c8 of 8 bytes by task 18600 on cpu 0: __list_add include/linux/list.h:73 [inline] list_add include/linux/list.h:88 [inline] lruvec_add_folio include/linux/mm_inline.h:105 [inline] lru_add_fn+0x440/0x520 mm/swap.c:228 folio_batch_move_lru+0x1e1/0x2a0 mm/swap.c:246 folio_batch_add_and_move mm/swap.c:263 [inline] folio_add_lru+0xf1/0x140 mm/swap.c:490 filemap_add_folio+0xf8/0x150 mm/filemap.c:948 __filemap_get_folio+0x510/0x6d0 mm/filemap.c:1981 pagecache_get_page+0x26/0x190 mm/folio-compat.c:104 grab_cache_page_write_begin+0x2a/0x30 mm/folio-compat.c:116 ext4_da_write_begin+0x2dd/0x5f0 fs/ext4/inode.c:2988 generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3738 ext4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:270 ext4_file_write_iter+0x2e3/0x1210 call_write_iter include/linux/fs.h:2187 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x468/0x760 fs/read_write.c:578 ksys_write+0xe8/0x1a0 fs/read_write.c:631 __do_sys_write fs/read_write.c:643 [inline] __se_sys_write fs/read_write.c:640 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:640 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffffea0004a1d2c8 of 8 bytes by task 18611 on cpu 1: page_is_pfmemalloc include/linux/mm.h:1740 [inline] __skb_fill_page_desc include/linux/skbuff.h:2422 [inline] skb_fill_page_desc include/linux/skbuff.h:2443 [inline] tcp_build_frag+0x613/0xb20 net/ipv4/tcp.c:1018 do_tcp_sendpages+0x3e8/0xaf0 net/ipv4/tcp.c:1075 tcp_sendpage_locked net/ipv4/tcp.c:1140 [inline] tcp_sendpage+0x89/0xb0 net/ipv4/tcp.c:1150 inet_sendpage+0x7f/0xc0 net/ipv4/af_inet.c:833 kernel_sendpage+0x184/0x300 net/socket.c:3561 sock_sendpage+0x5a/0x70 net/socket.c:1054 pipe_to_sendpage+0x128/0x160 fs/splice.c:361 splice_from_pipe_feed fs/splice.c:415 [inline] __splice_from_pipe+0x222/0x4d0 fs/splice.c:559 splice_from_pipe fs/splice.c:594 [inline] generic_splice_sendpage+0x89/0xc0 fs/splice.c:743 do_splice_from fs/splice.c:764 [inline] direct_splice_actor+0x80/0xa0 fs/splice.c:931 splice_direct_to_actor+0x305/0x620 fs/splice.c:886 do_splice_direct+0xfb/0x180 fs/splice.c:974 do_sendfile+0x3bf/0x910 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1303 [inline] __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1303 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x0000000000000000 -> 0xffffea0004a1d288 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 18611 Comm: syz-executor.4 Not tainted 6.0.0-rc2-syzkaller-00248-ge022620b5d05-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Fixes: c07aea3ef4d4 ("mm: add a signature in struct page") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Shakeel Butt <shakeelb@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
657b991a |
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23-Aug-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
net: Fix data-races around sysctl_max_skb_frags. While reading sysctl_max_skb_frags, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 5f74f82ea34c ("net:Add sysctl_max_skb_frags") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2e23acd9 |
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17-Aug-2022 |
Cong Wang <cong.wang@bytedance.com> |
tcp: handle pure FIN case correctly When skb->len==0, the recv_actor() returns 0 too, but we also use 0 for error conditions. This patch amends this by propagating the errors to tcp_read_skb() so that we can distinguish skb->len==0 case from error cases. Fixes: 04919bed948d ("tcp: Introduce tcp_read_skb()") Reported-by: Eric Dumazet <edumazet@google.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
a8688821 |
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17-Aug-2022 |
Cong Wang <cong.wang@bytedance.com> |
tcp: refactor tcp_read_skb() a bit As tcp_read_skb() only reads one skb at a time, the while loop is unnecessary, we can turn it into an if. This also simplifies the code logic. Cc: Eric Dumazet <edumazet@google.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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c457985a |
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17-Aug-2022 |
Cong Wang <cong.wang@bytedance.com> |
tcp: fix tcp_cleanup_rbuf() for tcp_read_skb() tcp_cleanup_rbuf() retrieves the skb from sk_receive_queue, it assumes the skb is not yet dequeued. This is no longer true for tcp_read_skb() case where we dequeue the skb first. Fix this by introducing a helper __tcp_cleanup_rbuf() which does not require any skb and calling it in tcp_read_skb(). Fixes: 04919bed948d ("tcp: Introduce tcp_read_skb()") Cc: Eric Dumazet <edumazet@google.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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e9c6e797 |
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17-Aug-2022 |
Cong Wang <cong.wang@bytedance.com> |
tcp: fix sock skb accounting in tcp_read_skb() Before commit 965b57b469a5 ("net: Introduce a new proto_ops ->read_skb()"), skb was not dequeued from receive queue hence when we close TCP socket skb can be just flushed synchronously. After this commit, we have to uncharge skb immediately after being dequeued, otherwise it is still charged in the original sock. And we still need to retain skb->sk, as eBPF programs may extract sock information from skb->sk. Therefore, we have to call skb_set_owner_sk_safe() here. Fixes: 965b57b469a5 ("net: Introduce a new proto_ops ->read_skb()") Reported-and-tested-by: syzbot+a0e6f8738b58f7654417@syzkaller.appspotmail.com Tested-by: Stanislav Fomichev <sdf@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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3f92a64e |
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22-Jul-2022 |
Jakub Kicinski <kuba@kernel.org> |
tcp: allow tls to decrypt directly from the tcp rcv queue Expose TCP rx queue accessor and cleanup, so that TLS can decrypt directly from the TCP queue. The expectation is that the caller can access the skb returned from tcp_recv_skb() and up to inq bytes worth of data (some of which may be in ->next skbs) and then call tcp_read_done() when data has been consumed. The socket lock must be held continuously across those two operations. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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af9784d0 |
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26-Jun-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: diag: add support for TIME_WAIT sockets to tcp_abort() Currently, "ss -K -ta ..." does not support TIME_WAIT sockets. Issue has been raised at least two times in the past [1] [2] it is time to fix it. [1] https://lore.kernel.org/netdev/ba65f579-4e69-ae0d-4770-bc6234beb428@gmail.com/ [2] https://lore.kernel.org/netdev/CANn89i+R9RgmD=AQ4vX1Vb_SQAj4c3fi7-ZtQz-inYY4Sq4CMQ@mail.gmail.com/T/ While we are at it, use inet_sk_state_load() while tcp_abort() does not hold a lock on the socket. Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Link: https://lore.kernel.org/r/20220627121038.226500-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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965b57b4 |
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15-Jun-2022 |
Cong Wang <cong.wang@bytedance.com> |
net: Introduce a new proto_ops ->read_skb() Currently both splice() and sockmap use ->read_sock() to read skb from receive queue, but for sockmap we only read one entire skb at a time, so ->read_sock() is too conservative to use. Introduce a new proto_ops ->read_skb() which supports this sematic, with this we can finally pass the ownership of skb to recv actors. For non-TCP protocols, all ->read_sock() can be simply converted to ->read_skb(). Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20220615162014.89193-3-xiyou.wangcong@gmail.com
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#
04919bed |
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15-Jun-2022 |
Cong Wang <cong.wang@bytedance.com> |
tcp: Introduce tcp_read_skb() This patch inroduces tcp_read_skb() based on tcp_read_sock(), a preparation for the next patch which actually introduces a new sock ops. TCP is special here, because it has tcp_read_sock() which is mainly used by splice(). tcp_read_sock() supports partial read and arbitrary offset, neither of them is needed for sockmap. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20220615162014.89193-2-xiyou.wangcong@gmail.com
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fd8b330c |
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17-Jun-2022 |
David S. Miller <davem@davemloft.net> |
tcp: fix build... Remove accidental dup of tcp_wmem_schedule. Signed-off-by: David S. Miller <davem@davemloft.net>
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f54755f6 |
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14-Jun-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: fix possible freeze in tx path under memory pressure Blamed commit only dealt with applications issuing small writes. Issue here is that we allow to force memory schedule for the sk_buff allocation, but we have no guarantee that sendmsg() is able to copy some payload in it. In this patch, I make sure the socket can use up to tcp_wmem[0] bytes. For example, if we consider tcp_wmem[0] = 4096 (default on x86), and initial skb->truesize being 1280, tcp_sendmsg() is able to copy up to 2816 bytes under memory pressure. Before this patch a sendmsg() sending more than 2816 bytes would either block forever (if persistent memory pressure), or return -EAGAIN. For bigger MTU networks, it is advised to increase tcp_wmem[0] to avoid sending too small packets. v2: deal with zero copy paths. Fixes: 8e4d980ac215 ("tcp: fix behavior for epoll edge trigger") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Wei Wang <weiwan@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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849b425c |
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14-Jun-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: fix possible freeze in tx path under memory pressure Blamed commit only dealt with applications issuing small writes. Issue here is that we allow to force memory schedule for the sk_buff allocation, but we have no guarantee that sendmsg() is able to copy some payload in it. In this patch, I make sure the socket can use up to tcp_wmem[0] bytes. For example, if we consider tcp_wmem[0] = 4096 (default on x86), and initial skb->truesize being 1280, tcp_sendmsg() is able to copy up to 2816 bytes under memory pressure. Before this patch a sendmsg() sending more than 2816 bytes would either block forever (if persistent memory pressure), or return -EAGAIN. For bigger MTU networks, it is advised to increase tcp_wmem[0] to avoid sending too small packets. v2: deal with zero copy paths. Fixes: 8e4d980ac215 ("tcp: fix behavior for epoll edge trigger") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Wei Wang <weiwan@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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4890b686 |
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09-Jun-2022 |
Eric Dumazet <edumazet@google.com> |
net: keep sk->sk_forward_alloc as small as possible Currently, tcp_memory_allocated can hit tcp_mem[] limits quite fast. Each TCP socket can forward allocate up to 2 MB of memory, even after flow became less active. 10,000 sockets can have reserved 20 GB of memory, and we have no shrinker in place to reclaim that. Instead of trying to reclaim the extra allocations in some places, just keep sk->sk_forward_alloc values as small as possible. This should not impact performance too much now we have per-cpu reserves: Changes to tcp_memory_allocated should not be too frequent. For sockets not using SO_RESERVE_MEM: - idle sockets (no packets in tx/rx queues) have zero forward alloc. - non idle sockets have a forward alloc smaller than one page. Note: - Removal of SK_RECLAIM_CHUNK and SK_RECLAIM_THRESHOLD is left to MPTCP maintainers as a follow up. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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0defbb0a |
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09-Jun-2022 |
Eric Dumazet <edumazet@google.com> |
net: add per_cpu_fw_alloc field to struct proto Each protocol having a ->memory_allocated pointer gets a corresponding per-cpu reserve, that following patches will use. Instead of having reserved bytes per socket, we want to have per-cpu reserves. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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100fdd1f |
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09-Jun-2022 |
Eric Dumazet <edumazet@google.com> |
net: remove SK_MEM_QUANTUM and SK_MEM_QUANTUM_SHIFT Due to memcg interface, SK_MEM_QUANTUM is effectively PAGE_SIZE. This might change in the future, but it seems better to avoid the confusion. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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eb315a7d |
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12-Jul-2022 |
Pavel Begunkov <asml.silence@gmail.com> |
tcp: support externally provided ubufs Teach tcp how to use external ubuf_info provided in msghdr and also prepare it for managed frags by sprinkling skb_zcopy_downgrade_managed() when it could mix managed and not managed frags. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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e62d2e11 |
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26-Jul-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: fix IPv4-mapped support After the blamed commit, IPv4 SYN packets handled by a dual stack IPv6 socket are dropped, even if perfectly valid. $ nstat | grep MD5 TcpExtTCPMD5Failure 5 0.0 For a dual stack listener, an incoming IPv4 SYN packet would call tcp_inbound_md5_hash() with @family == AF_INET, while tp->af_specific is pointing to tcp_sock_ipv6_specific. Only later when an IPv4-mapped child is created, tp->af_specific is changed to tcp_sock_ipv6_mapped_specific. Fixes: 7bbb765b7349 ("net/tcp: Merge TCP-MD5 inbound callbacks") Reported-by: Brian Vazquez <brianvv@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Dmitry Safonov <dima@arista.com> Tested-by: Leonard Crestez <cdleonard@gmail.com> Link: https://lore.kernel.org/r/20220726115743.2759832-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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02739545 |
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22-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
net: Fix data-races around sysctl_[rw]mem(_offset)?. While reading these sysctl variables, they can be changed concurrently. Thus, we need to add READ_ONCE() to their readers. - .sysctl_rmem - .sysctl_rwmem - .sysctl_rmem_offset - .sysctl_wmem_offset - sysctl_tcp_rmem[1, 2] - sysctl_tcp_wmem[1, 2] - sysctl_decnet_rmem[1] - sysctl_decnet_wmem[1] - sysctl_tipc_rmem[1] Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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85225e6f |
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20-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix a data-race around sysctl_tcp_autocorking. While reading sysctl_tcp_autocorking, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: f54b311142a9 ("tcp: auto corking") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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5a542133 |
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15-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix data-races around sysctl_tcp_fastopen. While reading sysctl_tcp_fastopen, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 2100c8d2d9db ("net-tcp: Fast Open base") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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39e24435 |
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15-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix data-races around some timeout sysctl knobs. While reading these sysctl knobs, they can be changed concurrently. Thus, we need to add READ_ONCE() to their readers. - tcp_retries1 - tcp_retries2 - tcp_orphan_retries - tcp_fin_timeout Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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46778cd1 |
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15-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix data-races around sysctl_tcp_reordering. While reading sysctl_tcp_reordering, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
20a3b1c0 |
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15-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix data-races around sysctl_tcp_syn(ack)?_retries. While reading sysctl_tcp_syn(ack)?_retries, they can be changed concurrently. Thus, we need to add READ_ONCE() to their readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
47e6ab24 |
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06-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix a data-race around sysctl_tcp_max_orphans. While reading sysctl_tcp_max_orphans, it can be changed concurrently. So, we need to add READ_ONCE() to avoid a data-race. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
593d1ebe |
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15-Jun-2022 |
Joanne Koong <joannelkoong@gmail.com> |
Revert "net: Add a second bind table hashed by port and address" This reverts: commit d5a42de8bdbe ("net: Add a second bind table hashed by port and address") commit 538aaf9b2383 ("selftests: Add test for timing a bind request to a port with a populated bhash entry") Link: https://lore.kernel.org/netdev/20220520001834.2247810-1-kuba@kernel.org/ There are a few things that need to be fixed here: * Updating bhash2 in cases where the socket's rcv saddr changes * Adding bhash2 hashbucket locks Links to syzbot reports: https://lore.kernel.org/netdev/00000000000022208805e0df247a@google.com/ https://lore.kernel.org/netdev/0000000000003f33bc05dfaf44fe@google.com/ Fixes: d5a42de8bdbe ("net: Add a second bind table hashed by port and address") Reported-by: syzbot+015d756bbd1f8b5c8f09@syzkaller.appspotmail.com Reported-by: syzbot+98fd2d1422063b0f8c44@syzkaller.appspotmail.com Reported-by: syzbot+0a847a982613c6438fba@syzkaller.appspotmail.com Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://lore.kernel.org/r/20220615193213.2419568-1-joannelkoong@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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d5a42de8 |
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19-May-2022 |
Joanne Koong <joannelkoong@gmail.com> |
net: Add a second bind table hashed by port and address We currently have one tcp bind table (bhash) which hashes by port number only. In the socket bind path, we check for bind conflicts by traversing the specified port's inet_bind2_bucket while holding the bucket's spinlock (see inet_csk_get_port() and inet_csk_bind_conflict()). In instances where there are tons of sockets hashed to the same port at different addresses, checking for a bind conflict is time-intensive and can cause softirq cpu lockups, as well as stops new tcp connections since __inet_inherit_port() also contests for the spinlock. This patch proposes adding a second bind table, bhash2, that hashes by port and ip address. Searching the bhash2 table leads to significantly faster conflict resolution and less time holding the spinlock. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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cae3873c |
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11-May-2022 |
Martin KaFai Lau <kafai@fb.com> |
net: inet: Retire port only listening_hash The listen sk is currently stored in two hash tables, listening_hash (hashed by port) and lhash2 (hashed by port and address). After commit 0ee58dad5b06 ("net: tcp6: prefer listeners bound to an address") and commit d9fbc7f6431f ("net: tcp: prefer listeners bound to an address"), the TCP-SYN lookup fast path does not use listening_hash. The commit 05c0b35709c5 ("tcp: seq_file: Replace listening_hash with lhash2") also moved the seq_file (/proc/net/tcp) iteration usage from listening_hash to lhash2. There are still a few listening_hash usages left. One of them is inet_reuseport_add_sock() which uses the listening_hash to search a listen sk during the listen() system call. This turns out to be very slow on use cases that listen on many different VIPs at a popular port (e.g. 443). [ On top of the slowness in adding to the tail in the IPv6 case ]. The latter patch has a selftest to demonstrate this case. This patch takes this chance to move all remaining listening_hash usages to lhash2 and then retire listening_hash. Since most changes need to be done together, it is hard to cut the listening_hash to lhash2 switch into small patches. The changes in this patch is highlighted here for the review purpose. 1. Because of the listening_hash removal, lhash2 can use the sk->sk_nulls_node instead of the icsk->icsk_listen_portaddr_node. This will also keep the sk_unhashed() check to work as is after stop adding sk to listening_hash. The union is removed from inet_listen_hashbucket because only nulls_head is needed. 2. icsk->icsk_listen_portaddr_node and its helpers are removed. 3. The current lhash2 users needs to iterate with sk_nulls_node instead of icsk_listen_portaddr_node. One case is in the inet[6]_lhash2_lookup(). Another case is the seq_file iterator in tcp_ipv4.c. One thing to note is sk_nulls_next() is needed because the old inet_lhash2_for_each_icsk_continue() does a "next" first before iterating. 4. Move the remaining listening_hash usage to lhash2 inet_reuseport_add_sock() which this series is trying to improve. inet_diag.c and mptcp_diag.c are the final two remaining use cases and is moved to lhash2 now also. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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68822bdf |
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22-Apr-2022 |
Eric Dumazet <edumazet@google.com> |
net: generalize skb freeing deferral to per-cpu lists Logic added in commit f35f821935d8 ("tcp: defer skb freeing after socket lock is released") helped bulk TCP flows to move the cost of skbs frees outside of critical section where socket lock was held. But for RPC traffic, or hosts with RFS enabled, the solution is far from being ideal. For RPC traffic, recvmsg() has to return to user space right after skb payload has been consumed, meaning that BH handler has no chance to pick the skb before recvmsg() thread. This issue is more visible with BIG TCP, as more RPC fit one skb. For RFS, even if BH handler picks the skbs, they are still picked from the cpu on which user thread is running. Ideally, it is better to free the skbs (and associated page frags) on the cpu that originally allocated them. This patch removes the per socket anchor (sk->defer_list) and instead uses a per-cpu list, which will hold more skbs per round. This new per-cpu list is drained at the end of net_action_rx(), after incoming packets have been processed, to lower latencies. In normal conditions, skbs are added to the per-cpu list with no further action. In the (unlikely) cases where the cpu does not run net_action_rx() handler fast enough, we use an IPI to raise NET_RX_SOFTIRQ on the remote cpu. Also, we do not bother draining the per-cpu list from dev_cpu_dead() This is because skbs in this list have no requirement on how fast they should be freed. Note that we can add in the future a small per-cpu cache if we see any contention on sd->defer_lock. Tested on a pair of hosts with 100Gbit NIC, RFS enabled, and /proc/sys/net/ipv4/tcp_rmem[2] tuned to 16MB to work around page recycling strategy used by NIC driver (its page pool capacity being too small compared to number of skbs/pages held in sockets receive queues) Note that this tuning was only done to demonstrate worse conditions for skb freeing for this particular test. These conditions can happen in more general production workload. 10 runs of one TCP_STREAM flow Before: Average throughput: 49685 Mbit. Kernel profiles on cpu running user thread recvmsg() show high cost for skb freeing related functions (*) 57.81% [kernel] [k] copy_user_enhanced_fast_string (*) 12.87% [kernel] [k] skb_release_data (*) 4.25% [kernel] [k] __free_one_page (*) 3.57% [kernel] [k] __list_del_entry_valid 1.85% [kernel] [k] __netif_receive_skb_core 1.60% [kernel] [k] __skb_datagram_iter (*) 1.59% [kernel] [k] free_unref_page_commit (*) 1.16% [kernel] [k] __slab_free 1.16% [kernel] [k] _copy_to_iter (*) 1.01% [kernel] [k] kfree (*) 0.88% [kernel] [k] free_unref_page 0.57% [kernel] [k] ip6_rcv_core 0.55% [kernel] [k] ip6t_do_table 0.54% [kernel] [k] flush_smp_call_function_queue (*) 0.54% [kernel] [k] free_pcppages_bulk 0.51% [kernel] [k] llist_reverse_order 0.38% [kernel] [k] process_backlog (*) 0.38% [kernel] [k] free_pcp_prepare 0.37% [kernel] [k] tcp_recvmsg_locked (*) 0.37% [kernel] [k] __list_add_valid 0.34% [kernel] [k] sock_rfree 0.34% [kernel] [k] _raw_spin_lock_irq (*) 0.33% [kernel] [k] __page_cache_release 0.33% [kernel] [k] tcp_v6_rcv (*) 0.33% [kernel] [k] __put_page (*) 0.29% [kernel] [k] __mod_zone_page_state 0.27% [kernel] [k] _raw_spin_lock After patch: Average throughput: 73076 Mbit. Kernel profiles on cpu running user thread recvmsg() looks better: 81.35% [kernel] [k] copy_user_enhanced_fast_string 1.95% [kernel] [k] _copy_to_iter 1.95% [kernel] [k] __skb_datagram_iter 1.27% [kernel] [k] __netif_receive_skb_core 1.03% [kernel] [k] ip6t_do_table 0.60% [kernel] [k] sock_rfree 0.50% [kernel] [k] tcp_v6_rcv 0.47% [kernel] [k] ip6_rcv_core 0.45% [kernel] [k] read_tsc 0.44% [kernel] [k] _raw_spin_lock_irqsave 0.37% [kernel] [k] _raw_spin_lock 0.37% [kernel] [k] native_irq_return_iret 0.33% [kernel] [k] __inet6_lookup_established 0.31% [kernel] [k] ip6_protocol_deliver_rcu 0.29% [kernel] [k] tcp_rcv_established 0.29% [kernel] [k] llist_reverse_order v2: kdoc issue (kernel bots) do not defer if (alloc_cpu == smp_processor_id()) (Paolo) replace the sk_buff_head with a single-linked list (Jakub) add a READ_ONCE()/WRITE_ONCE() for the lockless read of sd->defer_list Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20220422201237.416238-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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ec095263 |
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11-Apr-2022 |
Oliver Hartkopp <socketcan@hartkopp.net> |
net: remove noblock parameter from recvmsg() entities The internal recvmsg() functions have two parameters 'flags' and 'noblock' that were merged inside skb_recv_datagram(). As a follow up patch to commit f4b41f062c42 ("net: remove noblock parameter from skb_recv_datagram()") this patch removes the separate 'noblock' parameter for recvmsg(). Analogue to the referenced patch for skb_recv_datagram() the 'flags' and 'noblock' parameters are unnecessarily split up with e.g. err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, flags & ~MSG_DONTWAIT, &addr_len); or in err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg, sk, msg, size, flags & MSG_DONTWAIT, flags & ~MSG_DONTWAIT, &addr_len); instead of simply using only flags all the time and check for MSG_DONTWAIT where needed (to preserve for the formerly separated no(n)block condition). Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/r/20220411124955.154876-1-socketcan@hartkopp.net Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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40570375 |
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05-Apr-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: add accessors to read/set tp->snd_cwnd We had various bugs over the years with code breaking the assumption that tp->snd_cwnd is greater than zero. Lately, syzbot reported the WARN_ON_ONCE(!tp->prior_cwnd) added in commit 8b8a321ff72c ("tcp: fix zero cwnd in tcp_cwnd_reduction") can trigger, and without a repro we would have to spend considerable time finding the bug. Instead of complaining too late, we want to catch where and when tp->snd_cwnd is set to an illegal value. Signed-off-by: Eric Dumazet <edumazet@google.com> Suggested-by: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Link: https://lore.kernel.org/r/20220405233538.947344-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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f94fd25c |
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28-Apr-2022 |
Jens Axboe <axboe@kernel.dk> |
tcp: pass back data left in socket after receive This is currently done for CMSG_INQ, add an ability to do so via struct msghdr as well and have CMSG_INQ use that too. If the caller sets msghdr->msg_get_inq, then we'll pass back the hint in msghdr->msg_inq. Rearrange struct msghdr a bit so we can add this member while shrinking it at the same time. On a 64-bit build, it was 96 bytes before this change and 88 bytes afterwards. Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/650c22ca-cffc-0255-9a05-2413a1e20826@kernel.dk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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b0de0cf4 |
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08-Mar-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: autocork: take MSG_EOR hint into consideration tcp_should_autocork() is evaluating if it makes senses to not immediately send current skb, hoping that user space will add more payload on it by the time TCP stack reacts to upcoming TX completions. If current skb got MSG_EOR mark, then we know that no further data will be added, it is therefore futile to wait. SOF_TIMESTAMPING_TX_ACK will become a bit more accurate, if prior packets are still in qdisc/device queues. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Link: https://lore.kernel.org/r/20220309054706.2857266-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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1330b6ef |
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07-Mar-2022 |
Jakub Kicinski <kuba@kernel.org> |
skb: make drop reason booleanable We have a number of cases where function returns drop/no drop decision as a boolean. Now that we want to report the reason code as well we have to pass extra output arguments. We can make the reason code evaluate correctly as bool. I believe we're good to reorder the reasons as they are reported to user space as strings. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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7bbb765b |
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23-Feb-2022 |
Dmitry Safonov <0x7f454c46@gmail.com> |
net/tcp: Merge TCP-MD5 inbound callbacks The functions do essentially the same work to verify TCP-MD5 sign. Code can be merged into one family-independent function in order to reduce copy'n'paste and generated code. Later with TCP-AO option added, this will allow to create one function that's responsible for segment verification, that will have all the different checks for MD5/AO/non-signed packets, which in turn will help to see checks for all corner-cases in one function, rather than spread around different families and functions. Cc: Eric Dumazet <edumazet@google.com> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Signed-off-by: Dmitry Safonov <dima@arista.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20220223175740.452397-1-dima@arista.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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ab14f180 |
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24-Jan-2022 |
David Ahern <dsahern@kernel.org> |
net: Adjust sk_gso_max_size once when set sk_gso_max_size is set based on the dst dev. Both users of it adjust the value by the same offset - (MAX_TCP_HEADER + 1). Rather than compute the same adjusted value on each call do the adjustment once when set. Signed-off-by: David Ahern <dsahern@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20220125024511.27480-1-dsahern@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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e3d5ea2c |
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02-Mar-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: make tcp_read_sock() more robust If recv_actor() returns an incorrect value, tcp_read_sock() might loop forever. Instead, issue a one time warning and make sure to make progress. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20220302161723.3910001-2-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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f8d9d938 |
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03-Feb-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: take care of mixed splice()/sendmsg(MSG_ZEROCOPY) case syzbot found that mixing sendpage() and sendmsg(MSG_ZEROCOPY) calls over the same TCP socket would again trigger the infamous warning in inet_sock_destruct() WARN_ON(sk_forward_alloc_get(sk)); While Talal took into account a mix of regular copied data and MSG_ZEROCOPY one in the same skb, the sendpage() path has been forgotten. We want the charging to happen for sendpage(), because pages could be coming from a pipe. What is missing is the downgrading of pure zerocopy status to make sure sk_forward_alloc will stay synced. Add tcp_downgrade_zcopy_pure() helper so that we can use it from the two callers. Fixes: 9b65b17db723 ("net: avoid double accounting for pure zerocopy skbs") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Talal Ahmad <talalahmad@google.com> Cc: Arjun Roy <arjunroy@google.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Link: https://lore.kernel.org/r/20220203225547.665114-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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479f5547 |
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31-Jan-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: fix mem under-charging with zerocopy sendmsg() We got reports of following warning in inet_sock_destruct() WARN_ON(sk_forward_alloc_get(sk)); Whenever we add a non zero-copy fragment to a pure zerocopy skb, we have to anticipate that whole skb->truesize will be uncharged when skb is finally freed. skb->data_len is the payload length. But the memory truesize estimated by __zerocopy_sg_from_iter() is page aligned. Fixes: 9b65b17db723 ("net: avoid double accounting for pure zerocopy skbs") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Talal Ahmad <talalahmad@google.com> Cc: Arjun Roy <arjunroy@google.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Link: https://lore.kernel.org/r/20220201065254.680532-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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ebdc1a03 |
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20-Jan-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: add a missing sk_defer_free_flush() in tcp_splice_read() Without it, splice users can hit the warning added in commit 79074a72d335 ("net: Flush deferred skb free on socket destroy") Fixes: f35f821935d8 ("tcp: defer skb freeing after socket lock is released") Fixes: 79074a72d335 ("net: Flush deferred skb free on socket destroy") Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Gal Pressman <gal@nvidia.com> Link: https://lore.kernel.org/r/20220120124530.925607-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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6fadaa56 |
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03-Dec-2021 |
Maxim Galaganov <max@internet.ru> |
tcp: expose __tcp_sock_set_cork and __tcp_sock_set_nodelay Expose __tcp_sock_set_cork() and __tcp_sock_set_nodelay() for use in MPTCP setsockopt code -- namely for syncing MPTCP socket options with subflows inside sync_socket_options() while already holding the subflow socket lock. Acked-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Maxim Galaganov <max@internet.ru> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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29fbc26e |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: do not call tcp_cleanup_rbuf() if we have a backlog Under pressure, tcp recvmsg() has logic to process the socket backlog, but calls tcp_cleanup_rbuf() right before. Avoiding sending ACK right before processing new segments makes a lot of sense, as this decrease the number of ACK packets, with no impact on effective ACK clocking. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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8bd172b7 |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: check local var (timeo) before socket fields in one test Testing timeo before sk_err/sk_state/sk_shutdown makes more sense. Modern applications use non-blocking IO, while a socket is terminated only once during its life time. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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f35f8219 |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: defer skb freeing after socket lock is released tcp recvmsg() (or rx zerocopy) spends a fair amount of time freeing skbs after their payload has been consumed. A typical ~64KB GRO packet has to release ~45 page references, eventually going to page allocator for each of them. Currently, this freeing is performed while socket lock is held, meaning that there is a high chance that BH handler has to queue incoming packets to tcp socket backlog. This can cause additional latencies, because the user thread has to process the backlog at release_sock() time, and while doing so, additional frames can be added by BH handler. This patch adds logic to defer these frees after socket lock is released, or directly from BH handler if possible. Being able to free these skbs from BH handler helps a lot, because this avoids the usual alloc/free assymetry, when BH handler and user thread do not run on same cpu or NUMA node. One cpu can now be fully utilized for the kernel->user copy, and another cpu is handling BH processing and skb/page allocs/frees (assuming RFS is not forcing use of a single CPU) Tested: 100Gbit NIC Max throughput for one TCP_STREAM flow, over 10 runs MTU : 1500 Before: 55 Gbit After: 66 Gbit MTU : 4096+(headers) Before: 82 Gbit After: 95 Gbit Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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3df684c1 |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: avoid indirect calls to sock_rfree TCP uses sk_eat_skb() when skbs can be removed from receive queue. However, the call to skb_orphan() from __kfree_skb() incurs an indirect call so sock_rfee(), which is more expensive than a direct call, especially for CONFIG_RETPOLINE=y. Add tcp_eat_recv_skb() function to make the call before __kfree_skb(). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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b96c51bd |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: tp->urg_data is unlikely to be set Use some unlikely() hints in the fast path. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7b6a893a |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate races around tp->urg_data tcp_poll() and tcp_ioctl() are reading tp->urg_data without socket lock owned. Also, it is faster to first check tp->urg_data in tcp_poll(), then tp->urg_seq == tp->copied_seq, because tp->urg_seq is located in a different/cold cache line. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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0307a0b7 |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate data-races on tp->segs_in and tp->data_segs_in tcp_segs_in() can be called from BH, while socket spinlock is held but socket owned by user, eventually reading these fields from tcp_get_info() Found by code inspection, no need to backport this patch to older kernels. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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93afcfd1 |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: small optimization in tcp recvmsg() When reading large chunks of data, incoming packets might be added to the backlog from BH. tcp recvmsg() detects the backlog queue is not empty, and uses a release_sock()/lock_sock() pair to process this backlog. We now have __sk_flush_backlog() to perform this a bit faster. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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91b6d325 |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
net: cache align tcp_memory_allocated, tcp_sockets_allocated tcp_memory_allocated and tcp_sockets_allocated often share a common cache line, source of false sharing. Also take care of udp_memory_allocated and mptcp_sockets_allocated. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d0d598ca |
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15-Nov-2021 |
Eric Dumazet <edumazet@google.com> |
net: remove sk_route_forced_caps We were only using one bit, and we can replace it by sk_is_tcp() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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8f905c0e |
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20-Dec-2021 |
Eric Dumazet <edumazet@google.com> |
inet: fully convert sk->sk_rx_dst to RCU rules syzbot reported various issues around early demux, one being included in this changelog [1] sk->sk_rx_dst is using RCU protection without clearly documenting it. And following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv() are not following standard RCU rules. [a] dst_release(dst); [b] sk->sk_rx_dst = NULL; They look wrong because a delete operation of RCU protected pointer is supposed to clear the pointer before the call_rcu()/synchronize_rcu() guarding actual memory freeing. In some cases indeed, dst could be freed before [b] is done. We could cheat by clearing sk_rx_dst before calling dst_release(), but this seems the right time to stick to standard RCU annotations and debugging facilities. [1] BUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline] BUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792 Read of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204 CPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 dst_check include/net/dst.h:470 [inline] tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792 ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340 ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583 ip_sublist_rcv net/ipv4/ip_input.c:609 [inline] ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline] __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556 __netif_receive_skb_list net/core/dev.c:5608 [inline] netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699 gro_normal_list net/core/dev.c:5853 [inline] gro_normal_list net/core/dev.c:5849 [inline] napi_complete_done+0x1f1/0x880 net/core/dev.c:6590 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557 __napi_poll+0xaf/0x440 net/core/dev.c:7023 napi_poll net/core/dev.c:7090 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7177 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629 RIP: 0033:0x7f5e972bfd57 Code: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e <48> 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73 RSP: 002b:00007fff8a413210 EFLAGS: 00000283 RAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45 RDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45 RBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9 R10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0 R13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019 </TASK> Allocated by task 13: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3234 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247 dst_alloc+0x146/0x1f0 net/core/dst.c:92 rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613 ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:2340 ip_route_input_rcu net/ipv4/route.c:2470 [inline] ip_route_input_noref+0x116/0x2a0 net/ipv4/route.c:2415 ip_rcv_finish_core.constprop.0+0x288/0x1e80 net/ipv4/ip_input.c:354 ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583 ip_sublist_rcv net/ipv4/ip_input.c:609 [inline] ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline] __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556 __netif_receive_skb_list net/core/dev.c:5608 [inline] netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699 gro_normal_list net/core/dev.c:5853 [inline] gro_normal_list net/core/dev.c:5849 [inline] napi_complete_done+0x1f1/0x880 net/core/dev.c:6590 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557 __napi_poll+0xaf/0x440 net/core/dev.c:7023 napi_poll net/core/dev.c:7090 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7177 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 Freed by task 13: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749 slab_free mm/slub.c:3513 [inline] kmem_cache_free+0xbd/0x5d0 mm/slub.c:3530 dst_destroy+0x2d6/0x3f0 net/core/dst.c:127 rcu_do_batch kernel/rcu/tree.c:2506 [inline] rcu_core+0x7ab/0x1470 kernel/rcu/tree.c:2741 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 Last potentially related work creation: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 __kasan_record_aux_stack+0xf5/0x120 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:2985 [inline] call_rcu+0xb1/0x740 kernel/rcu/tree.c:3065 dst_release net/core/dst.c:177 [inline] dst_release+0x79/0xe0 net/core/dst.c:167 tcp_v4_do_rcv+0x612/0x8d0 net/ipv4/tcp_ipv4.c:1712 sk_backlog_rcv include/net/sock.h:1030 [inline] __release_sock+0x134/0x3b0 net/core/sock.c:2768 release_sock+0x54/0x1b0 net/core/sock.c:3300 tcp_sendmsg+0x36/0x40 net/ipv4/tcp.c:1441 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 sock_write_iter+0x289/0x3c0 net/socket.c:1057 call_write_iter include/linux/fs.h:2162 [inline] new_sync_write+0x429/0x660 fs/read_write.c:503 vfs_write+0x7cd/0xae0 fs/read_write.c:590 ksys_write+0x1ee/0x250 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88807f1cb700 which belongs to the cache ip_dst_cache of size 176 The buggy address is located 58 bytes inside of 176-byte region [ffff88807f1cb700, ffff88807f1cb7b0) The buggy address belongs to the page: page:ffffea0001fc72c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f1cb flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 dead000000000100 dead000000000122 ffff8881413bb780 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 5, ts 108466983062, free_ts 108048976062 prep_new_page mm/page_alloc.c:2418 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4149 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5369 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191 alloc_slab_page mm/slub.c:1793 [inline] allocate_slab mm/slub.c:1930 [inline] new_slab+0x32d/0x4a0 mm/slub.c:1993 ___slab_alloc+0x918/0xfe0 mm/slub.c:3022 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3109 slab_alloc_node mm/slub.c:3200 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x35c/0x3a0 mm/slub.c:3247 dst_alloc+0x146/0x1f0 net/core/dst.c:92 rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613 __mkroute_output net/ipv4/route.c:2564 [inline] ip_route_output_key_hash_rcu+0x921/0x2d00 net/ipv4/route.c:2791 ip_route_output_key_hash+0x18b/0x300 net/ipv4/route.c:2619 __ip_route_output_key include/net/route.h:126 [inline] ip_route_output_flow+0x23/0x150 net/ipv4/route.c:2850 ip_route_output_key include/net/route.h:142 [inline] geneve_get_v4_rt+0x3a6/0x830 drivers/net/geneve.c:809 geneve_xmit_skb drivers/net/geneve.c:899 [inline] geneve_xmit+0xc4a/0x3540 drivers/net/geneve.c:1082 __netdev_start_xmit include/linux/netdevice.h:4994 [inline] netdev_start_xmit include/linux/netdevice.h:5008 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606 __dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1338 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1389 free_unref_page_prepare mm/page_alloc.c:3309 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3388 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3234 [inline] kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3270 __alloc_skb+0x215/0x340 net/core/skbuff.c:414 alloc_skb include/linux/skbuff.h:1126 [inline] alloc_skb_with_frags+0x93/0x620 net/core/skbuff.c:6078 sock_alloc_send_pskb+0x783/0x910 net/core/sock.c:2575 mld_newpack+0x1df/0x770 net/ipv6/mcast.c:1754 add_grhead+0x265/0x330 net/ipv6/mcast.c:1857 add_grec+0x1053/0x14e0 net/ipv6/mcast.c:1995 mld_send_initial_cr.part.0+0xf6/0x230 net/ipv6/mcast.c:2242 mld_send_initial_cr net/ipv6/mcast.c:1232 [inline] mld_dad_work+0x1d3/0x690 net/ipv6/mcast.c:2268 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 Memory state around the buggy address: ffff88807f1cb600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807f1cb680: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc >ffff88807f1cb700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807f1cb780: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ffff88807f1cb800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 41063e9dd119 ("ipv4: Early TCP socket demux.") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20211220143330.680945-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
70701b83 |
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11-Nov-2021 |
Arjun Roy <arjunroy@google.com> |
tcp: Fix uninitialized access in skb frags array for Rx 0cp. TCP Receive zerocopy iterates through the SKB queue via tcp_recv_skb(), acquiring a pointer to an SKB and an offset within that SKB to read from. From there, it iterates the SKB frags array to determine which offset to start remapping pages from. However, this is built on the assumption that the offset read so far within the SKB is smaller than the SKB length. If this assumption is violated, we can attempt to read an invalid frags array element, which would cause a fault. tcp_recv_skb() can cause such an SKB to be returned when the TCP FIN flag is set. Therefore, we must guard against this occurrence inside skb_advance_frag(). One way that we can reproduce this error follows: 1) In a receiver program, call getsockopt(TCP_ZEROCOPY_RECEIVE) with: char some_array[32 * 1024]; struct tcp_zerocopy_receive zc = { .copybuf_address = (__u64) &some_array[0], .copybuf_len = 32 * 1024, }; 2) In a sender program, after a TCP handshake, send the following sequence of packets: i) Seq = [X, X+4000] ii) Seq = [X+4000, X+5000] iii) Seq = [X+4000, X+5000], Flags = FIN | URG, urgptr=1000 (This can happen without URG, if we have a signal pending, but URG is a convenient way to reproduce the behaviour). In this case, the following event sequence will occur on the receiver: tcp_zerocopy_receive(): -> receive_fallback_to_copy() // copybuf_len >= inq -> tcp_recvmsg_locked() // reads 5000 bytes, then breaks due to URG -> tcp_recv_skb() // yields skb with skb->len == offset -> tcp_zerocopy_set_hint_for_skb() -> skb_advance_to_frag() // will returns a frags ptr. >= nr_frags -> find_next_mappable_frag() // will dereference this bad frags ptr. With this patch, skb_advance_to_frag() will no longer return an invalid frags pointer, and will return NULL instead, fixing the issue. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive") Link: https://lore.kernel.org/r/20211111235215.2605384-1-arjunroy.kdev@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
9b65b17d |
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02-Nov-2021 |
Talal Ahmad <talalahmad@google.com> |
net: avoid double accounting for pure zerocopy skbs Track skbs containing only zerocopy data and avoid charging them to kernel memory to correctly account the memory utilization for msg_zerocopy. All of the data in such skbs is held in user pages which are already accounted to user. Before this change, they are charged again in kernel in __zerocopy_sg_from_iter. The charging in kernel is excessive because data is not being copied into skb frags. This excessive charging can lead to kernel going into memory pressure state which impacts all sockets in the system adversely. Mark pure zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove charge/uncharge for data in such skbs. Initially, an skb is marked pure zerocopy when it is empty and in zerocopy path. skb can then change from a pure zerocopy skb to mixed data skb (zerocopy and copy data) if it is at tail of write queue and there is room available in it and non-zerocopy data is being sent in the next sendmsg call. At this time sk_mem_charge is done for the pure zerocopied data and the pure zerocopy flag is unmarked. We found that this happens very rarely on workloads that pass MSG_ZEROCOPY. A pure zerocopy skb can later be coalesced into normal skb if they are next to each other in queue but this patch prevents coalescing from happening. This avoids complexity of charging when skb downgrades from pure zerocopy to mixed. This is also rare. In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge for SKB_TRUESIZE(skb_end_offset(skb)) is done for sk_mem_charge in tcp_skb_entail for an skb without data. Testing with the msg_zerocopy.c benchmark between two hosts(100G nics) with zerocopy showed that before this patch the 'sock' variable in memory.stat for cgroup2 that tracks sum of sk_forward_alloc, sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this change it is 0. This is due to no charge to sk_forward_alloc for zerocopy data and shows memory utilization for kernel is lowered. With this commit we don't see the warning we saw in previous commit which resulted in commit 84882cf72cd774cf16fd338bdbf00f69ac9f9194. Signed-off-by: Talal Ahmad <talalahmad@google.com> Acked-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a1554c00 |
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05-Nov-2021 |
Mianhan Liu <liumh1@shanghaitech.edu.cn> |
include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.h nr_free_buffer_pages could be exposed through mm.h instead of swap.h. The advantage of this change is that it can reduce the obsolete includes. For example, net/ipv4/tcp.c wouldn't need swap.h any more since it has already included mm.h. Similarly, after checking all the other files, it comes that tcp.c, udp.c meter.c ,... follow the same rule, so these files can have swap.h removed too. Moreover, after preprocessing all the files that use nr_free_buffer_pages, it turns out that those files have already included mm.h.Thus, we can move nr_free_buffer_pages from swap.h to mm.h safely. This change will not affect the compilation of other files. Link: https://lkml.kernel.org/r/20210912133640.1624-1-liumh1@shanghaitech.edu.cn Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn> Cc: Jakub Kicinski <kuba@kernel.org> CC: Ulf Hansson <ulf.hansson@linaro.org> Cc: "David S . Miller" <davem@davemloft.net> Cc: Simon Horman <horms@verge.net.au> Cc: Pravin B Shelar <pshelar@ovn.org> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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84882cf7 |
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01-Nov-2021 |
Jakub Kicinski <kuba@kernel.org> |
Revert "net: avoid double accounting for pure zerocopy skbs" This reverts commit f1a456f8f3fc5828d8abcad941860380ae147b1d. WARNING: CPU: 1 PID: 6819 at net/core/skbuff.c:5429 skb_try_coalesce+0x78b/0x7e0 CPU: 1 PID: 6819 Comm: xxxxxxx Kdump: loaded Tainted: G S 5.15.0-04194-gd852503f7711 #16 RIP: 0010:skb_try_coalesce+0x78b/0x7e0 Code: e8 2a bf 41 ff 44 8b b3 bc 00 00 00 48 8b 7c 24 30 e8 19 c0 41 ff 44 89 f0 48 03 83 c0 00 00 00 48 89 44 24 40 e9 47 fb ff ff <0f> 0b e9 ca fc ff ff 4c 8d 70 ff 48 83 c0 07 48 89 44 24 38 e9 61 RSP: 0018:ffff88881f449688 EFLAGS: 00010282 RAX: 00000000fffffe96 RBX: ffff8881566e4460 RCX: ffffffff82079f7e RDX: 0000000000000003 RSI: dffffc0000000000 RDI: ffff8881566e47b0 RBP: ffff8881566e46e0 R08: ffffed102619235d R09: ffffed102619235d R10: ffff888130c91ae3 R11: ffffed102619235c R12: ffff88881f4498a0 R13: 0000000000000056 R14: 0000000000000009 R15: ffff888130c91ac0 FS: 00007fec2cbb9700(0000) GS:ffff88881f440000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fec1b060d80 CR3: 00000003acf94005 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> tcp_try_coalesce+0xeb/0x290 ? tcp_parse_options+0x610/0x610 ? mark_held_locks+0x79/0xa0 tcp_queue_rcv+0x69/0x2f0 tcp_rcv_established+0xa49/0xd40 ? tcp_data_queue+0x18a0/0x18a0 tcp_v6_do_rcv+0x1c9/0x880 ? rt6_mtu_change_route+0x100/0x100 tcp_v6_rcv+0x1624/0x1830 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
f1a456f8 |
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29-Oct-2021 |
Talal Ahmad <talalahmad@google.com> |
net: avoid double accounting for pure zerocopy skbs Track skbs with only zerocopy data and avoid charging them to kernel memory to correctly account the memory utilization for msg_zerocopy. All of the data in such skbs is held in user pages which are already accounted to user. Before this change, they are charged again in kernel in __zerocopy_sg_from_iter. The charging in kernel is excessive because data is not being copied into skb frags. This excessive charging can lead to kernel going into memory pressure state which impacts all sockets in the system adversely. Mark pure zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove charge/uncharge for data in such skbs. Initially, an skb is marked pure zerocopy when it is empty and in zerocopy path. skb can then change from a pure zerocopy skb to mixed data skb (zerocopy and copy data) if it is at tail of write queue and there is room available in it and non-zerocopy data is being sent in the next sendmsg call. At this time sk_mem_charge is done for the pure zerocopied data and the pure zerocopy flag is unmarked. We found that this happens very rarely on workloads that pass MSG_ZEROCOPY. A pure zerocopy skb can later be coalesced into normal skb if they are next to each other in queue but this patch prevents coalescing from happening. This avoids complexity of charging when skb downgrades from pure zerocopy to mixed. This is also rare. In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge for SKB_TRUESIZE(MAX_TCP_HEADER) is done for sk_mem_charge in tcp_skb_entail for an skb without data. Testing with the msg_zerocopy.c benchmark between two hosts(100G nics) with zerocopy showed that before this patch the 'sock' variable in memory.stat for cgroup2 that tracks sum of sk_forward_alloc, sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this change it is 0. This is due to no charge to sk_forward_alloc for zerocopy data and shows memory utilization for kernel is lowered. Signed-off-by: Talal Ahmad <talalahmad@google.com> Acked-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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03271f3a |
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29-Oct-2021 |
Talal Ahmad <talalahmad@google.com> |
tcp: rename sk_wmem_free_skb sk_wmem_free_skb() is only used by TCP. Rename it to make this clear, and move its declaration to include/net/tcp.h Signed-off-by: Talal Ahmad <talalahmad@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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8b7d8c2b |
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27-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: do not clear TCP_SKB_CB(skb)->sacked if already zero Freshly allocated skbs have zero in skb->cb[] already. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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4f226674 |
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27-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: do not clear skb->csum if already zero Freshly allocated skbs have their csum field cleared already. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a52fe46e |
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27-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: factorize ip_summed setting Setting skb->ip_summed to CHECKSUM_PARTIAL can be centralized in tcp_stream_alloc_skb() and __mptcp_do_alloc_tx_skb() instead of being done multiple times. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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f401da47 |
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27-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: no longer set skb->reserved_tailroom TCP/MPTCP sendmsg() no longer puts payload in skb->head, we can remove not needed code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
27728ba8 |
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27-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: cleanup tcp_remove_empty_skb() use All tcp_remove_empty_skb() callers now use tcp_write_queue_tail() for the skb argument, we can therefore factorize code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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3ded97bc |
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27-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: remove dead code from tcp_sendmsg_locked() TCP sendmsg() no longer puts payload in skb head, we can remove dead code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c4322884 |
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25-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: remove unneeded code from tcp_stream_alloc_skb() Aligning @size argument to 4 bytes is not needed. The header alignment has nothing to do with @size. It really depends on skb->head alignment and MAX_TCP_HEADER. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8a794df6 |
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25-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: use MAX_TCP_HEADER in tcp_stream_alloc_skb Both IPv4 and IPv6 uses same reserve, no need risking cache line misses to fetch its value. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f8dd3b8d |
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25-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: rename sk_stream_alloc_skb sk_stream_alloc_skb() is only used by TCP. Rename it to make this clear, and move its declaration to include/net/tcp.h Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cf12e6f9 |
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24-Oct-2021 |
Jon Maxwell <jmaxwell37@gmail.com> |
tcp: don't free a FIN sk_buff in tcp_remove_empty_skb() v1: Implement a more general statement as recommended by Eric Dumazet. The sequence number will be advanced, so this check will fix the FIN case and other cases. A customer reported sockets stuck in the CLOSING state. A Vmcore revealed that the write_queue was not empty as determined by tcp_write_queue_empty() but the sk_buff containing the FIN flag had been freed and the socket was zombied in that state. Corresponding pcaps show no FIN from the Linux kernel on the wire. Some instrumentation was added to the kernel and it was found that there is a timing window where tcp_sendmsg() can run after tcp_send_fin(). tcp_sendmsg() will hit an error, for example: 1269 ▹ if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))↩ 1270 ▹ ▹ goto do_error;↩ tcp_remove_empty_skb() will then free the FIN sk_buff as "skb->len == 0". The TCP socket is now wedged in the FIN-WAIT-1 state because the FIN is never sent. If the other side sends a FIN packet the socket will transition to CLOSING and remain that way until the system is rebooted. Fix this by checking for the FIN flag in the sk_buff and don't free it if that is the case. Testing confirmed that fixed the issue. Fixes: fdfc5c8594c2 ("tcp: remove empty skb from write queue in error cases") Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Reported-by: Monir Zouaoui <Monir.Zouaoui@mail.schwarz> Reported-by: Simon Stier <simon.stier@mail.schwarz> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
19757ceb |
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14-Oct-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: switch orphan_count to bare per-cpu counters Use of percpu_counter structure to track count of orphaned sockets is causing problems on modern hosts with 256 cpus or more. Stefan Bach reported a serious spinlock contention in real workloads, that I was able to reproduce with a netfilter rule dropping incoming FIN packets. 53.56% server [kernel.kallsyms] [k] queued_spin_lock_slowpath | ---queued_spin_lock_slowpath | --53.51%--_raw_spin_lock_irqsave | --53.51%--__percpu_counter_sum tcp_check_oom | |--39.03%--__tcp_close | tcp_close | inet_release | inet6_release | sock_close | __fput | ____fput | task_work_run | exit_to_usermode_loop | do_syscall_64 | entry_SYSCALL_64_after_hwframe | __GI___libc_close | --14.48%--tcp_out_of_resources tcp_write_timeout tcp_retransmit_timer tcp_write_timer_handler tcp_write_timer call_timer_fn expire_timers __run_timers run_timer_softirq __softirqentry_text_start As explained in commit cf86a086a180 ("net/dst: use a smaller percpu_counter batch for dst entries accounting"), default batch size is too big for the default value of tcp_max_orphans (262144). But even if we reduce batch sizes, there would still be cases where the estimated count of orphans is beyond the limit, and where tcp_too_many_orphans() has to call the expensive percpu_counter_sum_positive(). One solution is to use plain per-cpu counters, and have a timer to periodically refresh this cache. Updating this cache every 100ms seems about right, tcp pressure state is not radically changing over shorter periods. percpu_counter was nice 15 years ago while hosts had less than 16 cpus, not anymore by current standards. v2: Fix the build issue for CONFIG_CRYPTO_DEV_CHELSIO_TLS=m, reported by kernel test robot <lkp@intel.com> Remove unused socket argument from tcp_too_many_orphans() Fixes: dd24c00191d5 ("net: Use a percpu_counter for orphan_count") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Stefan Bach <sfb@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d8b81175 |
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22-Sep-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: remove sk_{tr}x_skb_cache This reverts the following patches : - commit 2e05fcae83c4 ("tcp: fix compile error if !CONFIG_SYSCTL") - commit 4f661542a402 ("tcp: fix zerocopy and notsent_lowat issues") - commit 472c2e07eef0 ("tcp: add one skb cache for tx") - commit 8b27dae5a2e8 ("tcp: add one skb cache for rx") Having a cache of one skb (in each direction) per TCP socket is fragile, since it can cause a significant increase of memory needs, and not good enough for high speed flows anyway where more than one skb is needed. We want instead to add a generic infrastructure, with more flexible per-cpu caches, for alien NUMA nodes. Acked-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ff6fb083 |
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22-Sep-2021 |
Paolo Abeni <pabeni@redhat.com> |
tcp: make tcp_build_frag() static After the previous patch the mentioned helper is used only inside its compilation unit: let's make it static. RFC -> v1: - preserve the tcp_build_frag() helper (Eric) Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
04d8825c |
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22-Sep-2021 |
Paolo Abeni <pabeni@redhat.com> |
tcp: expose the tcp_mark_push() and tcp_skb_entail() helpers the tcp_skb_entail() helper is actually skb_entail(), renamed to provide proper scope. The two helper will be used by the next patch. RFC -> v1: - rename skb_entail to tcp_skb_entail (Eric) Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7b50ecfc |
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08-Oct-2021 |
Cong Wang <cong.wang@bytedance.com> |
net: Rename ->stream_memory_read to ->sock_is_readable The proto ops ->stream_memory_read() is currently only used by TCP to check whether psock queue is empty or not. We need to rename it before reusing it for non-TCP protocols, and adjust the exsiting users accordingly. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211008203306.37525-2-xiyou.wangcong@gmail.com
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3aa7857f |
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25-Aug-2021 |
Neil Spring <ntspring@fb.com> |
tcp: enable mid stream window clamp The TCP_WINDOW_CLAMP socket option is defined in tcp(7) to "Bound the size of the advertised window to this value." Window clamping is distributed across two variables, window_clamp ("Maximal window to advertise" in tcp.h) and rcv_ssthresh ("Current window clamp"). This patch updates the function where the window clamp is set to also reduce the current window clamp, rcv_sshthresh, if needed. With this, setting the TCP_WINDOW_CLAMP option has the documented effect of limiting the window. Signed-off-by: Neil Spring <ntspring@fb.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20210825210117.1668371-1-ntspring@fb.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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990c74e3 |
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19-Jul-2021 |
Vasily Averin <vvs@virtuozzo.com> |
memcg: enable accounting for inet_bin_bucket cache net namespace can create up to 64K tcp and dccp ports and force kernel to allocate up to several megabytes of memory per netns for inet_bind_bucket objects. It makes sense to account for them to restrict the host's memory consumption from inside the memcg-limited container. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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358ed624 |
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09-Jul-2021 |
Talal Ahmad <talalahmad@google.com> |
tcp: call sk_wmem_schedule before sk_mem_charge in zerocopy path sk_wmem_schedule makes sure that sk_forward_alloc has enough bytes for charging that is going to be done by sk_mem_charge. In the transmit zerocopy path, there is sk_mem_charge but there was no call to sk_wmem_schedule. This change adds that call. Without this call to sk_wmem_schedule, sk_forward_alloc can go negetive which is a bug because sk_forward_alloc is a per-socket space that has been forward charged so this can't be negative. Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Signed-off-by: Talal Ahmad <talalahmad@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Wei Wang <weiwan@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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e3ae2365 |
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27-Jun-2021 |
Alexander Aring <aahringo@redhat.com> |
net: sock: introduce sk_error_report This patch introduces a function wrapper to call the sk_error_report callback. That will prepare to add additional handling whenever sk_error_report is called, for example to trace socket errors. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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892bfd3d |
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03-Jun-2021 |
Florian Westphal <fw@strlen.de> |
tcp: export timestamp helpers for mptcp MPTCP is builtin, so no need to add EXPORT_SYMBOL()s. It will be used to support SO_TIMESTAMP(NS) ancillary messages in the mptcp receive path. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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47bdd1db |
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28-Jun-2021 |
Liam Howlett <liam.howlett@oracle.com> |
net/ipv5/tcp: use vma_lookup() in tcp_zerocopy_receive() Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-13-Liam.Howlett@Oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Davidlohr Bueso <dbueso@suse.de> Cc: David Miller <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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a6f8ee58 |
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06-May-2021 |
Arjun Roy <arjunroy@google.com> |
tcp: Specify cmsgbuf is user pointer for receive zerocopy. A prior change (1f466e1f15cf) introduces separate handling for ->msg_control depending on whether the pointer is a kernel or user pointer. However, while tcp receive zerocopy is using this field, it is not properly annotating that the buffer in this case is a user pointer. This can cause faults when the improper mechanism is used within put_cmsg(). This patch simply annotates tcp receive zerocopy's use as explicitly being a user pointer. Fixes: 7eeba1706eba ("tcp: Add receive timestamp support for receive zerocopy.") Signed-off-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20210506223530.2266456-1-arjunroy.kdev@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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a7150e38 |
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09-Apr-2021 |
Eric Dumazet <edumazet@google.com> |
Revert "tcp: Reset tcp connections in SYN-SENT state" This reverts commit e880f8b3a24a73704731a7227ed5fee14bd90192. 1) Patch has not been properly tested, and is wrong [1] 2) Patch submission did not include TCP maintainer (this is me) [1] divide error: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 8426 Comm: syz-executor478 Not tainted 5.12.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__tcp_select_window+0x56d/0xad0 net/ipv4/tcp_output.c:3015 Code: 44 89 ff e8 d5 cd f0 f9 45 39 e7 0f 8d 20 ff ff ff e8 f7 c7 f0 f9 44 89 e3 e9 13 ff ff ff e8 ea c7 f0 f9 44 89 e0 44 89 e3 99 <f7> 7c 24 04 29 d3 e9 fc fe ff ff e8 d3 c7 f0 f9 41 f7 dc bf 1f 00 RSP: 0018:ffffc9000184fac0 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff87832e76 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff87832e14 R11: 0000000000000000 R12: 0000000000000000 R13: 1ffff92000309f5c R14: 0000000000000000 R15: 0000000000000000 FS: 00000000023eb300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc2b5f426c0 CR3: 000000001c5cf000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tcp_select_window net/ipv4/tcp_output.c:264 [inline] __tcp_transmit_skb+0xa82/0x38f0 net/ipv4/tcp_output.c:1351 tcp_transmit_skb net/ipv4/tcp_output.c:1423 [inline] tcp_send_active_reset+0x475/0x8e0 net/ipv4/tcp_output.c:3449 tcp_disconnect+0x15a9/0x1e60 net/ipv4/tcp.c:2955 inet_shutdown+0x260/0x430 net/ipv4/af_inet.c:905 __sys_shutdown_sock net/socket.c:2189 [inline] __sys_shutdown_sock net/socket.c:2183 [inline] __sys_shutdown+0xf1/0x1b0 net/socket.c:2201 __do_sys_shutdown net/socket.c:2209 [inline] __se_sys_shutdown net/socket.c:2207 [inline] __x64_sys_shutdown+0x50/0x70 net/socket.c:2207 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: e880f8b3a24a ("tcp: Reset tcp connections in SYN-SENT state") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Manoj Basapathi <manojbm@codeaurora.org> Cc: Sauvik Saha <ssaha@codeaurora.org> Link: https://lore.kernel.org/r/20210409170237.274904-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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e880f8b3 |
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05-Apr-2021 |
Manoj Basapathi <manojbm@codeaurora.org> |
tcp: Reset tcp connections in SYN-SENT state Userspace sends tcp connection (sock) destroy on network switch i.e switching the default network of the device between multiple networks(Cellular/Wifi/Ethernet). Kernel though doesn't send reset for the connections in SYN-SENT state and these connections continue to remain. Even as per RFC 793, there is no hard rule to not send RST on ABORT in this state. Modify tcp_abort and tcp_disconnect behavior to send RST for connections in syn-sent state to avoid lingering connections on network switch. Signed-off-by: Manoj Basapathi <manojbm@codeaurora.org> Signed-off-by: Sauvik Saha <ssaha@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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97a19caf |
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17-Mar-2021 |
Yonghong Song <yhs@fb.com> |
bpf: net: Emit anonymous enum with BPF_TCP_CLOSE value explicitly The selftest failed to compile with clang-built bpf-next. Adding LLVM=1 to your vmlinux and selftest build will use clang. The error message is: progs/test_sk_storage_tracing.c:38:18: error: use of undeclared identifier 'BPF_TCP_CLOSE' if (newstate == BPF_TCP_CLOSE) ^ 1 error generated. make: *** [Makefile:423: /bpf-next/tools/testing/selftests/bpf/test_sk_storage_tracing.o] Error 1 The reason for the failure is that BPF_TCP_CLOSE, a value of an anonymous enum defined in uapi bpf.h, is not defined in vmlinux.h. gcc does not have this problem. Since vmlinux.h is derived from BTF which is derived from vmlinux DWARF, that means gcc-produced vmlinux DWARF has BPF_TCP_CLOSE while llvm-produced vmlinux DWARF does not have. BPF_TCP_CLOSE is referenced in net/ipv4/tcp.c as BUILD_BUG_ON((int)BPF_TCP_CLOSE != (int)TCP_CLOSE); The following test mimics the above BUILD_BUG_ON, preprocessed with clang compiler, and shows gcc DWARF contains BPF_TCP_CLOSE while llvm DWARF does not. $ cat t.c enum { BPF_TCP_ESTABLISHED = 1, BPF_TCP_CLOSE = 7, }; enum { TCP_ESTABLISHED = 1, TCP_CLOSE = 7, }; int test() { do { extern void __compiletime_assert_767(void) ; if ((int)BPF_TCP_CLOSE != (int)TCP_CLOSE) __compiletime_assert_767(); } while (0); return 0; } $ clang t.c -O2 -c -g && llvm-dwarfdump t.o | grep BPF_TCP_CLOSE $ gcc t.c -O2 -c -g && llvm-dwarfdump t.o | grep BPF_TCP_CLOSE DW_AT_name ("BPF_TCP_CLOSE") Further checking clang code find clang actually tried to evaluate condition at compile time. If it is definitely true/false, it will perform optimization and the whole if condition will be removed before generating IR/debuginfo. This patch explicited add an expression after the above mentioned BUILD_BUG_ON in net/ipv4/tcp.c like (void)BPF_TCP_ESTABLISHED to enable generation of debuginfo for the anonymous enum which also includes BPF_TCP_CLOSE. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210317174132.589276-1-yhs@fb.com
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#
8811f4a9 |
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01-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: add sanity tests to TCP_QUEUE_SEQ Qingyu Li reported a syzkaller bug where the repro changes RCV SEQ _after_ restoring data in the receive queue. mprotect(0x4aa000, 12288, PROT_READ) = 0 mmap(0x1ffff000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x1ffff000 mmap(0x20000000, 16777216, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x20000000 mmap(0x21000000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x21000000 socket(AF_INET6, SOCK_STREAM, IPPROTO_IP) = 3 setsockopt(3, SOL_TCP, TCP_REPAIR, [1], 4) = 0 connect(3, {sa_family=AF_INET6, sin6_port=htons(0), sin6_flowinfo=htonl(0), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_scope_id=0}, 28) = 0 setsockopt(3, SOL_TCP, TCP_REPAIR_QUEUE, [1], 4) = 0 sendmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="0x0000000000000003\0\0", iov_len=20}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 20 setsockopt(3, SOL_TCP, TCP_REPAIR, [0], 4) = 0 setsockopt(3, SOL_TCP, TCP_QUEUE_SEQ, [128], 4) = 0 recvfrom(3, NULL, 20, 0, NULL, NULL) = -1 ECONNRESET (Connection reset by peer) syslog shows: [ 111.205099] TCP recvmsg seq # bug 2: copied 80, seq 0, rcvnxt 80, fl 0 [ 111.207894] WARNING: CPU: 1 PID: 356 at net/ipv4/tcp.c:2343 tcp_recvmsg_locked+0x90e/0x29a0 This should not be allowed. TCP_QUEUE_SEQ should only be used when queues are empty. This patch fixes this case, and the tx path as well. Fixes: ee9952831cfd ("tcp: Initial repair mode") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=212005 Reported-by: Qingyu Li <ieatmuttonchuan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2107d45f |
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25-Feb-2021 |
Arjun Roy <arjunroy@google.com> |
tcp: Fix sign comparison bug in getsockopt(TCP_ZEROCOPY_RECEIVE) getsockopt(TCP_ZEROCOPY_RECEIVE) has a bug where we read a user-provided "len" field of type signed int, and then compare the value to the result of an "offsetofend" operation, which is unsigned. Negative values provided by the user will be promoted to large positive numbers; thus checking that len < offsetofend() will return false when the intention was that it return true. Note that while len is originally checked for negative values earlier on in do_tcp_getsockopt(), subsequent calls to get_user() re-read the value from userspace which may have changed in the meantime. Therefore, re-add the check for negative values after the call to get_user in the handler code for TCP_ZEROCOPY_RECEIVE. Fixes: c8856c051454 ("tcp-zerocopy: Return inq along with tcp receive zerocopy.") Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Arjun Roy <arjunroy@google.com> Link: https://lore.kernel.org/r/20210225232628.4033281-1-arjunroy.kdev@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
05dc72ab |
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12-Feb-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: factorize logic into tcp_epollin_ready() Both tcp_data_ready() and tcp_stream_is_readable() share the same logic. Add tcp_epollin_ready() helper to avoid duplication. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Arjun Roy <arjunroy@google.com> Cc: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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3c5a2fd0 |
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11-Feb-2021 |
Arjun Roy <arjunroy@google.com> |
tcp: Sanitize CMSG flags and reserved args in tcp_zerocopy_receive. Explicitly define reserved field and require it and any subsequent fields to be zero-valued for now. Additionally, limit the valid CMSG flags that tcp_zerocopy_receive accepts. Fixes: 7eeba1706eba ("tcp: Add receive timestamp support for receive zerocopy.") Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Suggested-by: David Ahern <dsahern@gmail.com> Suggested-by: Leon Romanovsky <leon@kernel.org> Suggested-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7eeba170 |
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20-Jan-2021 |
Arjun Roy <arjunroy@google.com> |
tcp: Add receive timestamp support for receive zerocopy. tcp_recvmsg() uses the CMSG mechanism to receive control information like packet receive timestamps. This patch adds CMSG fields to struct tcp_zerocopy_receive, and provides receive timestamps if available to the user. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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925bba24 |
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20-Jan-2021 |
Arjun Roy <arjunroy@google.com> |
tcp: Remove CMSG magic numbers for tcp_recvmsg(). At present, tcp_recvmsg() uses flags to track if any CMSGs are pending and what those CMSGs are. These flags are currently magic numbers, used only within tcp_recvmsg(). To prepare for receive timestamp support in tcp receive zerocopy, gently refactor these magic numbers into enums. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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e7ed11ee |
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20-Jan-2021 |
Yousuk Seung <ysseung@google.com> |
tcp: add TTL to SCM_TIMESTAMPING_OPT_STATS This patch adds TCP_NLA_TTL to SCM_TIMESTAMPING_OPT_STATS that exports the time-to-live or hop limit of the latest incoming packet with SCM_TSTAMP_ACK. The value exported may not be from the packet that acks the sequence when incoming packets are aggregated. Exporting the time-to-live or hop limit value of incoming packets helps to estimate the hop count of the path of the flow that may change over time. Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Link: https://lore.kernel.org/r/20210120204155.552275-1-ysseung@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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9cacf81f |
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15-Jan-2021 |
Stanislav Fomichev <sdf@google.com> |
bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE Add custom implementation of getsockopt hook for TCP_ZEROCOPY_RECEIVE. We skip generic hooks for TCP_ZEROCOPY_RECEIVE and have a custom call in do_tcp_getsockopt using the on-stack data. This removes 3% overhead for locking/unlocking the socket. Without this patch: 3.38% 0.07% tcp_mmap [kernel.kallsyms] [k] __cgroup_bpf_run_filter_getsockopt | --3.30%--__cgroup_bpf_run_filter_getsockopt | --0.81%--__kmalloc With the patch applied: 0.52% 0.12% tcp_mmap [kernel.kallsyms] [k] __cgroup_bpf_run_filter_getsockopt_kern Note, exporting uapi/tcp.h requires removing netinet/tcp.h from test_progs.h because those headers have confliciting definitions. Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210115163501.805133-2-sdf@google.com
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8e044917 |
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06-Jan-2021 |
Jonathan Lemon <jonathan.lemon@gmail.com> |
skbuff: Rename skb_zcopy_{get|put} to net_zcopy_{get|put} Unlike the rest of the skb_zcopy_ functions, these routines operate on a 'struct ubuf', not a skb. Remove the 'skb_' prefix from the naming to make things clearer. Suggested-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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06b4feb3 |
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06-Jan-2021 |
Jonathan Lemon <jonathan.lemon@gmail.com> |
net: group skb_shinfo zerocopy related bits together. In preparation for expanded zerocopy (TX and RX), move the zerocopy related bits out of tx_flags into their own flag word. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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8c793822 |
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06-Jan-2021 |
Jonathan Lemon <jonathan.lemon@gmail.com> |
skbuff: rename sock_zerocopy_* to msg_zerocopy_* At Willem's suggestion, rename the sock_zerocopy_* functions so that they match the MSG_ZEROCOPY flag, which makes it clear they are specific to this zerocopy implementation. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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236a6b1c |
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06-Jan-2021 |
Jonathan Lemon <jonathan.lemon@gmail.com> |
skbuff: Call sock_zerocopy_put_abort from skb_zcopy_put_abort The sock_zerocopy_put_abort function contains logic which is specific to the current zerocopy implementation. Add a wrapper which checks the callback and dispatches apppropriately. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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59776362 |
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06-Jan-2021 |
Jonathan Lemon <jonathan.lemon@gmail.com> |
skbuff: replace sock_zerocopy_put() with skb_zcopy_put() Replace sock_zerocopy_put with the generic skb_zcopy_put() function. Pass 'true' as the success argument, as this is identical to no change. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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9d9b1ee0 |
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15-Jan-2021 |
Enke Chen <enchen@paloaltonetworks.com> |
tcp: fix TCP_USER_TIMEOUT with zero window The TCP session does not terminate with TCP_USER_TIMEOUT when data remain untransmitted due to zero window. The number of unanswered zero-window probes (tcp_probes_out) is reset to zero with incoming acks irrespective of the window size, as described in tcp_probe_timer(): RFC 1122 4.2.2.17 requires the sender to stay open indefinitely as long as the receiver continues to respond probes. We support this by default and reset icsk_probes_out with incoming ACKs. This counter, however, is the wrong one to be used in calculating the duration that the window remains closed and data remain untransmitted. Thanks to Jonathan Maxwell <jmaxwell37@gmail.com> for diagnosing the actual issue. In this patch a new timestamp is introduced for the socket in order to track the elapsed time for the zero-window probes that have not been answered with any non-zero window ack. Fixes: 9721e709fa68 ("tcp: simplify window probe aborting on USER_TIMEOUT") Reported-by: William McCall <william.mccall@gmail.com> Co-developed-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Enke Chen <enchen@paloaltonetworks.com> Reviewed-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20210115223058.GA39267@localhost.localdomain Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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e0fecb28 |
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10-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
tcp: correctly handle increased zerocopy args struct size A prior patch increased the size of struct tcp_zerocopy_receive but did not update do_tcp_getsockopt() handling to properly account for this. This patch simply reintroduces content erroneously cut from the referenced prior patch that handles the new struct size. Fixes: 18fb76ed5386 ("net-zerocopy: Copy straggler unaligned data for TCP Rx. zerocopy.") Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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94ab9eb9 |
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02-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
net-zerocopy: Defer vm zap unless actually needed. Zapping pages is required only if we are calling vm_insert_page into a region where pages had previously been mapped. Receive zerocopy allows reusing such regions, and hitherto called zap_page_range() before calling vm_insert_page() in that range. zap_page_range() can also be triggered from userspace with madvise(MADV_DONTNEED). If userspace is configured to call this before reusing a segment, or if there was nothing mapped at this virtual address to begin with, we can avoid calling zap_page_range() under the socket lock. That said, if userspace does not do that, then we are still responsible for calling zap_page_range(). This patch adds a flag that the user can use to hint to the kernel that a zap is not required. If the flag is not set, or if an older user application does not have a flags field at all, then the kernel calls zap_page_range as before. Also, if the flag is set but a zap is still required, the kernel performs that zap as necessary. Thus incorrectly indicating that a zap can be avoided does not change the correctness of operation. It also increases the batchsize for vm_insert_pages and prefetches the page struct for the batch since we're about to bump the refcount. An alternative mechanism could be to not have a flag, assume by default a zap is not needed, and fall back to zapping if needed. However, this would harm performance for older applications for which a zap is necessary, and thus we implement it with an explicit flag so newer applications can opt in. When using RPC-style traffic with medium sized (tens of KB) RPCs, this change yields an efficency improvement of about 30% for QPS/CPU usage. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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0c3936d3 |
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02-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
net-zerocopy: Set zerocopy hint when data is copied Set zerocopy hint, event when falling back to copy, so that the pending data can be efficiently received using zerocopy when possible. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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f21a3c48 |
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02-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
net-zerocopy: Introduce short-circuit small reads. Sometimes, we may call tcp receive zerocopy when inq is 0, or inq < PAGE_SIZE, or inq is generally small enough that it is cheaper to copy rather than remap pages. In these cases, we may want to either return early (inq=0) or attempt to use the provided copy buffer to simply copy the received data. This allows us to save both system call overhead and the latency of acquiring mmap_sem in read mode for cases where it would be useless to do so. This patchset enables this behaviour by: 1. Returning quickly if inq is 0. 2. Attempting to perform a regular copy if a hybrid copybuffer is provided and it is large enough to absorb all available bytes. 3. Return quickly if no such buffer was provided and there are less than PAGE_SIZE bytes available. For small RPC ping-pong workloads, normally we would have 1 getsockopt(), 1 recvmsg() and 1 sendmsg() call per RPC. With this change, we remove the recvmsg() call entirely, reducing the syscall overhead by about 33%. In testing with small (hundreds of bytes) RPC traffic, this yields a syscall reduction of about 33% and an efficiency gain of about 3-5% when defined as QPS/CPU Util. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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936ced41 |
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02-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
net-zerocopy: Fast return if inq < PAGE_SIZE Sometimes, we may call tcp receive zerocopy when inq is 0, or inq < PAGE_SIZE, in which case we cannot remap pages. In this case, simply return the appropriate hint for regular copying without taking mmap_sem. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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98917cf0 |
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02-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
net-zerocopy: Refactor frag-is-remappable test. Refactor frag-is-remappable test for tcp receive zerocopy. This is part of a patch set that introduces short-circuited hybrid copies for small receive operations, which results in roughly 33% fewer syscalls for small RPC scenarios. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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7fba5309 |
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02-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
net-zerocopy: Refactor skb frag fast-forward op. Refactor skb frag fast-forwarding for tcp receive zerocopy. This is part of a patch set that introduces short-circuited hybrid copies for small receive operations, which results in roughly 33% fewer syscalls for small RPC scenarios. skb_advance_to_frag(), given a skb and an offset into the skb, iterates from the first frag for the skb until we're at the frag specified by the offset. Assuming the offset provided refers to how many bytes in the skb are already read, the returned frag points to the next frag we may read from, while offset_frag is set to the number of bytes from this frag that we have already read. If frag is not null and offset_frag is equal to 0, then we may be able to map this frag's page into the process address space with vm_insert_page(). However, if offset_frag is not equal to 0, then we cannot do so. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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2cd81161 |
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02-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
net-tcp: Introduce tcp_recvmsg_locked(). Refactor tcp_recvmsg() by splitting it into locked and unlocked portions. Callers already holding the socket lock and not using ERRQUEUE/cmsg/busy polling can simply call tcp_recvmsg_locked(). This is in preparation for a short-circuit copy performed by TCP receive zerocopy for small (< PAGE_SIZE, or otherwise requested by the user) reads. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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18fb76ed |
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02-Dec-2020 |
Arjun Roy <arjunroy@google.com> |
net-zerocopy: Copy straggler unaligned data for TCP Rx. zerocopy. When TCP receive zerocopy does not successfully map the entire requested space, it outputs a 'hint' that the caller should recvmsg(). Augment zerocopy to accept a user buffer that it tries to copy this hint into - if it is possible to copy the entire hint, it will do so. This elides a recvmsg() call for received traffic that isn't exactly page-aligned in size. This was tested with RPC-style traffic of arbitrary sizes. Normally, each received message required at least one getsockopt() call, and one recvmsg() call for the remaining unaligned data. With this change, almost all of the recvmsg() calls are eliminated, leading to a savings of about 25%-50% in number of system calls for RPC-style workloads. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
cb811109 |
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02-Dec-2020 |
Prankur gupta <prankgup@fb.com> |
bpf: Adds support for setting window clamp Adds a new bpf_setsockopt for TCP sockets, TCP_BPF_WINDOW_CLAMP, which sets the maximum receiver window size. It will be useful for limiting receiver window based on RTT. Signed-off-by: Prankur gupta <prankgup@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201202213152.435886-2-prankgup@fb.com
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77c3c956 |
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16-Nov-2020 |
Paolo Abeni <pabeni@redhat.com> |
tcp: factor out __tcp_close() helper unlocked version of protocol level close, will be used by MPTCP to allow decouple orphaning and subflow level close. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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b796d04b |
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16-Nov-2020 |
Paolo Abeni <pabeni@redhat.com> |
tcp: factor out tcp_build_frag() Will be needed by the next patch, as MPTCP needs to handle directly the error/memory-allocation-needed path. No functional changes intended. Additionally let MPTCP code access the tcp_remove_empty_skb() helper. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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435ccfa8 |
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23-Oct-2020 |
Arjun Roy <arjunroy@google.com> |
tcp: Prevent low rmem stalls with SO_RCVLOWAT. With SO_RCVLOWAT, under memory pressure, it is possible to enter a state where: 1. We have not received enough bytes to satisfy SO_RCVLOWAT. 2. We have not entered buffer pressure (see tcp_rmem_pressure()). 3. But, we do not have enough buffer space to accept more packets. In this case, we advertise 0 rwnd (due to #3) but the application does not drain the receive queue (no wakeup because of #1 and #2) so the flow stalls. Modify the heuristic for SO_RCVLOWAT so that, if we are advertising rwnd<=rcv_mss, force a wakeup to prevent a stall. Without this patch, setting tcp_rmem to 6143 and disabling TCP autotune causes a stalled flow. With this patch, no stall occurs. This is with RPC-style traffic with large messages. Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users") Signed-off-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20201023184709.217614-1-arjunroy.kdev@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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cf83a17e |
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02-Oct-2020 |
Coly Li <colyli@suse.de> |
tcp: use sendpage_ok() to detect misused .sendpage commit a10674bf2406 ("tcp: detecting the misuse of .sendpage for Slab objects") adds the checks for Slab pages, but the pages don't have page_count are still missing from the check. Network layer's sendpage method is not designed to send page_count 0 pages neither, therefore both PageSlab() and page_count() should be both checked for the sending page. This is exactly what sendpage_ok() does. This patch uses sendpage_ok() in do_tcp_sendpages() to detect misused .sendpage, to make the code more robust. Fixes: a10674bf2406 ("tcp: detecting the misuse of .sendpage for Slab objects") Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Coly Li <colyli@suse.de> Cc: Vasily Averin <vvs@virtuozzo.com> Cc: David S. Miller <davem@davemloft.net> Cc: stable@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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b6b6d653 |
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30-Sep-2020 |
Eric Dumazet <edumazet@google.com> |
inet: remove icsk_ack.blocked TCP has been using it to work around the possibility of tcp_delack_timer() finding the socket owned by user. After commit 6f458dfb4092 ("tcp: improve latencies of timer triggered events") we added TCP_DELACK_TIMER_DEFERRED atomic bit for more immediate recovery, so we can get rid of icsk_ack.blocked This frees space that following patch will reuse. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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afb83012 |
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14-Sep-2020 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: schedule EPOLLOUT after a partial sendmsg For EPOLLET, applications must call sendmsg until they get EAGAIN. Otherwise, there is no guarantee that EPOLLOUT is sent if there was a failure upon memory allocation. As a result on high-speed NICs, userspace observes multiple small sendmsgs after a partial sendmsg until EAGAIN, since TCP can send 1-2 TSOs in between two sendmsg syscalls: // One large partial send due to memory allocation failure. sendmsg(20MB) = 2MB // Many small sends until EAGAIN. sendmsg(18MB) = 64KB sendmsg(17.9MB) = 128KB sendmsg(17.8MB) = 64KB ... sendmsg(...) = EAGAIN // At this point, userspace can assume an EPOLLOUT. To fix this, set the SOCK_NOSPACE on all partial sendmsg scenarios to guarantee that we send EPOLLOUT after partial sendmsg. After this commit userspace can assume that it will receive an EPOLLOUT after the first partial sendmsg. This EPOLLOUT will benefit from sk_stream_write_space() logic delaying the EPOLLOUT until significant space is available in write queue. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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8ba3c9d1 |
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14-Sep-2020 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: return EPOLLOUT from tcp_poll only when notsent_bytes is half the limit If there was any event available on the TCP socket, tcp_poll() will be called to retrieve all the events. In tcp_poll(), we call sk_stream_is_writeable() which returns true as long as we are at least one byte below notsent_lowat. This will result in quite a few spurious EPLLOUT and frequent tiny sendmsg() calls as a result. Similar to sk_stream_write_space(), use __sk_stream_is_writeable with a wake value of 1, so that we set EPOLLOUT only if half the space is available for write. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c76c6956 |
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14-Sep-2020 |
Paolo Abeni <pabeni@redhat.com> |
mptcp: call tcp_cleanup_rbuf on subflows That is needed to let the subflows announce promptly when new space is available in the receive buffer. tcp_cleanup_rbuf() is currently a static function, drop the scope modifier and add a declaration in the TCP header. Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
29a94932 |
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10-Sep-2020 |
Neal Cardwell <ncardwell@google.com> |
tcp: simplify tcp_set_congestion_control(): Always reinitialize Now that the previous patches ensure that all call sites for tcp_set_congestion_control() want to initialize congestion control, we can simplify tcp_set_congestion_control() by removing the reinit argument and the code to support it. Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Kevin Yang <yyd@google.com> Cc: Lawrence Brakmo <brakmo@fb.com>
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#
8919a9b3 |
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10-Sep-2020 |
Neal Cardwell <ncardwell@google.com> |
tcp: Only init congestion control if not initialized already Change tcp_init_transfer() to only initialize congestion control if it has not been initialized already. With this new approach, we can arrange things so that if the EBPF code sets the congestion control by calling setsockopt(TCP_CONGESTION) then tcp_init_transfer() will not re-initialize the CC module. This is an approach that has the following beneficial properties: (1) This allows CC module customizations made by the EBPF called in tcp_init_transfer() to persist, and not be wiped out by a later call to tcp_init_congestion_control() in tcp_init_transfer(). (2) Does not flip the order of EBPF and CC init, to avoid causing bugs for existing code upstream that depends on the current order. (3) Does not cause 2 initializations for for CC in the case where the EBPF called in tcp_init_transfer() wants to set the CC to a new CC algorithm. (4) Allows follow-on simplifications to the code in net/core/filter.c and net/ipv4/tcp_cong.c, which currently both have some complexity to special-case CC initialization to avoid double CC initialization if EBPF sets the CC. Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Kevin Yang <yyd@google.com> Cc: Lawrence Brakmo <brakmo@fb.com>
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#
267cf9fa |
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20-Aug-2020 |
Martin KaFai Lau <kafai@fb.com> |
tcp: bpf: Optionally store mac header in TCP_SAVE_SYN This patch is adapted from Eric's patch in an earlier discussion [1]. The TCP_SAVE_SYN currently only stores the network header and tcp header. This patch allows it to optionally store the mac header also if the setsockopt's optval is 2. It requires one more bit for the "save_syn" bit field in tcp_sock. This patch achieves this by moving the syn_smc bit next to the is_mptcp. The syn_smc is currently used with the TCP experimental option. Since syn_smc is only used when CONFIG_SMC is enabled, this patch also puts the "IS_ENABLED(CONFIG_SMC)" around it like the is_mptcp did with "IS_ENABLED(CONFIG_MPTCP)". The mac_hdrlen is also stored in the "struct saved_syn" to allow a quick offset from the bpf prog if it chooses to start getting from the network header or the tcp header. [1]: https://lore.kernel.org/netdev/CANn89iLJNWh6bkH7DNhy_kmcAexuUCccqERqe7z2QsvPhGrYPQ@mail.gmail.com/ Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/bpf/20200820190123.2886935-1-kafai@fb.com
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#
ca584ba0 |
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20-Aug-2020 |
Martin KaFai Lau <kafai@fb.com> |
tcp: bpf: Add TCP_BPF_RTO_MIN for bpf_setsockopt This patch adds bpf_setsockopt(TCP_BPF_RTO_MIN) to allow bpf prog to set the min rto of a connection. It could be used together with the earlier patch which has added bpf_setsockopt(TCP_BPF_DELACK_MAX). A later selftest patch will communicate the max delay ack in a bpf tcp header option and then the receiving side can use bpf_setsockopt(TCP_BPF_RTO_MIN) to set a shorter rto. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200820190027.2884170-1-kafai@fb.com
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#
2b8ee4f0 |
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20-Aug-2020 |
Martin KaFai Lau <kafai@fb.com> |
tcp: bpf: Add TCP_BPF_DELACK_MAX setsockopt This change is mostly from an internal patch and adapts it from sysctl config to the bpf_setsockopt setup. The bpf_prog can set the max delay ack by using bpf_setsockopt(TCP_BPF_DELACK_MAX). This max delay ack can be communicated to its peer through bpf header option. The receiving peer can then use this max delay ack and set a potentially lower rto by using bpf_setsockopt(TCP_BPF_RTO_MIN) which will be introduced in the next patch. Another later selftest patch will also use it like the above to show how to write and parse bpf tcp header option. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200820190021.2884000-1-kafai@fb.com
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#
70a217f1 |
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20-Aug-2020 |
Martin KaFai Lau <kafai@fb.com> |
tcp: Use a struct to represent a saved_syn The TCP_SAVE_SYN has both the network header and tcp header. The total length of the saved syn packet is currently stored in the first 4 bytes (u32) of an array and the actual packet data is stored after that. A later patch will add a bpf helper that allows to get the tcp header alone from the saved syn without the network header. It will be more convenient to have a direct offset to a specific header instead of re-parsing it. This requires to separately store the network hdrlen. The total header length (i.e. network + tcp) is still needed for the current usage in getsockopt. Although this total length can be obtained by looking into the tcphdr and then get the (th->doff << 2), this patch chooses to directly store the tcp hdrlen in the second four bytes of this newly created "struct saved_syn". By using a new struct, it can give a readable name to each individual header length. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200820190014.2883694-1-kafai@fb.com
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#
f19008e6 |
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10-Aug-2020 |
Jason Baron <jbaron@akamai.com> |
tcp: correct read of TFO keys on big endian systems When TFO keys are read back on big endian systems either via the global sysctl interface or via getsockopt() using TCP_FASTOPEN_KEY, the values don't match what was written. For example, on s390x: # echo "1-2-3-4" > /proc/sys/net/ipv4/tcp_fastopen_key # cat /proc/sys/net/ipv4/tcp_fastopen_key 02000000-01000000-04000000-03000000 Instead of: # cat /proc/sys/net/ipv4/tcp_fastopen_key 00000001-00000002-00000003-00000004 Fix this by converting to the correct endianness on read. This was reported by Colin Ian King when running the 'tcp_fastopen_backup_key' net selftest on s390x, which depends on the read value matching what was written. I've confirmed that the test now passes on big and little endian systems. Signed-off-by: Jason Baron <jbaron@akamai.com> Fixes: 438ac88009bc ("net: fastopen: robustness and endianness fixes for SipHash") Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Eric Dumazet <edumazet@google.com> Reported-and-tested-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
48040793 |
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30-Jul-2020 |
Yousuk Seung <ysseung@google.com> |
tcp: add earliest departure time to SCM_TIMESTAMPING_OPT_STATS This change adds TCP_NLA_EDT to SCM_TIMESTAMPING_OPT_STATS that reports the earliest departure time(EDT) of the timestamped skb. By tracking EDT values of the skb from different timestamps, we can observe when and how much the value changed. This allows to measure the precise delay injected on the sender host e.g. by a bpf-base throttler. Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d3c48151 |
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28-Jul-2020 |
Christoph Hellwig <hch@lst.de> |
net: remove sockptr_advance sockptr_advance never properly worked. Replace it with _offset variants of copy_from_sockptr and copy_to_sockptr. Fixes: ba423fdaa589 ("net: add a new sockptr_t type") Reported-by: Jason A. Donenfeld <Jason@zx2c4.com> Reported-by: Ido Schimmel <idosch@idosch.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> Tested-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a7b75c5a |
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23-Jul-2020 |
Christoph Hellwig <hch@lst.de> |
net: pass a sockptr_t into ->setsockopt Rework the remaining setsockopt code to pass a sockptr_t instead of a plain user pointer. This removes the last remaining set_fs(KERNEL_DS) outside of architecture specific code. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154] Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d38d2b00 |
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23-Jul-2020 |
Christoph Hellwig <hch@lst.de> |
net/tcp: switch do_tcp_setsockopt to sockptr_t Pass a sockptr_t to prepare for set_fs-less handling of the kernel pointer from bpf-cgroup. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d4c19c49 |
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23-Jul-2020 |
Christoph Hellwig <hch@lst.de> |
net/tcp: switch ->md5_parse to sockptr_t Pass a sockptr_t to prepare for set_fs-less handling of the kernel pointer from bpf-cgroup. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3021ad52 |
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17-Jul-2020 |
Christoph Hellwig <hch@lst.de> |
net/ipv6: remove compat_ipv6_{get,set}sockopt Handle the few cases that need special treatment in-line using in_compat_syscall(). This also removes all the now unused compat_{get,set}sockopt methods. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ce69e563 |
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08-Jul-2020 |
Christoph Paasch <cpaasch@apple.com> |
tcp: make sure listeners don't initialize congestion-control state syzkaller found its way into setsockopt with TCP_CONGESTION "cdg". tcp_cdg_init() does a kcalloc to store the gradients. As sk_clone_lock just copies all the memory, the allocated pointer will be copied as well, if the app called setsockopt(..., TCP_CONGESTION) on the listener. If now the socket will be destroyed before the congestion-control has properly been initialized (through a call to tcp_init_transfer), we will end up freeing memory that does not belong to that particular socket, opening the door to a double-free: [ 11.413102] ================================================================== [ 11.414181] BUG: KASAN: double-free or invalid-free in tcp_cleanup_congestion_control+0x58/0xd0 [ 11.415329] [ 11.415560] CPU: 3 PID: 4884 Comm: syz-executor.5 Not tainted 5.8.0-rc2 #80 [ 11.416544] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 [ 11.418148] Call Trace: [ 11.418534] <IRQ> [ 11.418834] dump_stack+0x7d/0xb0 [ 11.419297] print_address_description.constprop.0+0x1a/0x210 [ 11.422079] kasan_report_invalid_free+0x51/0x80 [ 11.423433] __kasan_slab_free+0x15e/0x170 [ 11.424761] kfree+0x8c/0x230 [ 11.425157] tcp_cleanup_congestion_control+0x58/0xd0 [ 11.425872] tcp_v4_destroy_sock+0x57/0x5a0 [ 11.426493] inet_csk_destroy_sock+0x153/0x2c0 [ 11.427093] tcp_v4_syn_recv_sock+0xb29/0x1100 [ 11.427731] tcp_get_cookie_sock+0xc3/0x4a0 [ 11.429457] cookie_v4_check+0x13d0/0x2500 [ 11.433189] tcp_v4_do_rcv+0x60e/0x780 [ 11.433727] tcp_v4_rcv+0x2869/0x2e10 [ 11.437143] ip_protocol_deliver_rcu+0x23/0x190 [ 11.437810] ip_local_deliver+0x294/0x350 [ 11.439566] __netif_receive_skb_one_core+0x15d/0x1a0 [ 11.441995] process_backlog+0x1b1/0x6b0 [ 11.443148] net_rx_action+0x37e/0xc40 [ 11.445361] __do_softirq+0x18c/0x61a [ 11.445881] asm_call_on_stack+0x12/0x20 [ 11.446409] </IRQ> [ 11.446716] do_softirq_own_stack+0x34/0x40 [ 11.447259] do_softirq.part.0+0x26/0x30 [ 11.447827] __local_bh_enable_ip+0x46/0x50 [ 11.448406] ip_finish_output2+0x60f/0x1bc0 [ 11.450109] __ip_queue_xmit+0x71c/0x1b60 [ 11.451861] __tcp_transmit_skb+0x1727/0x3bb0 [ 11.453789] tcp_rcv_state_process+0x3070/0x4d3a [ 11.456810] tcp_v4_do_rcv+0x2ad/0x780 [ 11.457995] __release_sock+0x14b/0x2c0 [ 11.458529] release_sock+0x4a/0x170 [ 11.459005] __inet_stream_connect+0x467/0xc80 [ 11.461435] inet_stream_connect+0x4e/0xa0 [ 11.462043] __sys_connect+0x204/0x270 [ 11.465515] __x64_sys_connect+0x6a/0xb0 [ 11.466088] do_syscall_64+0x3e/0x70 [ 11.466617] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 11.467341] RIP: 0033:0x7f56046dc469 [ 11.467844] Code: Bad RIP value. [ 11.468282] RSP: 002b:00007f5604dccdd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a [ 11.469326] RAX: ffffffffffffffda RBX: 000000000068bf00 RCX: 00007f56046dc469 [ 11.470379] RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000004 [ 11.471311] RBP: 00000000ffffffff R08: 0000000000000000 R09: 0000000000000000 [ 11.472286] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 11.473341] R13: 000000000041427c R14: 00007f5604dcd5c0 R15: 0000000000000003 [ 11.474321] [ 11.474527] Allocated by task 4884: [ 11.475031] save_stack+0x1b/0x40 [ 11.475548] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 11.476182] tcp_cdg_init+0xf0/0x150 [ 11.476744] tcp_init_congestion_control+0x9b/0x3a0 [ 11.477435] tcp_set_congestion_control+0x270/0x32f [ 11.478088] do_tcp_setsockopt.isra.0+0x521/0x1a00 [ 11.478744] __sys_setsockopt+0xff/0x1e0 [ 11.479259] __x64_sys_setsockopt+0xb5/0x150 [ 11.479895] do_syscall_64+0x3e/0x70 [ 11.480395] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 11.481097] [ 11.481321] Freed by task 4872: [ 11.481783] save_stack+0x1b/0x40 [ 11.482230] __kasan_slab_free+0x12c/0x170 [ 11.482839] kfree+0x8c/0x230 [ 11.483240] tcp_cleanup_congestion_control+0x58/0xd0 [ 11.483948] tcp_v4_destroy_sock+0x57/0x5a0 [ 11.484502] inet_csk_destroy_sock+0x153/0x2c0 [ 11.485144] tcp_close+0x932/0xfe0 [ 11.485642] inet_release+0xc1/0x1c0 [ 11.486131] __sock_release+0xc0/0x270 [ 11.486697] sock_close+0xc/0x10 [ 11.487145] __fput+0x277/0x780 [ 11.487632] task_work_run+0xeb/0x180 [ 11.488118] __prepare_exit_to_usermode+0x15a/0x160 [ 11.488834] do_syscall_64+0x4a/0x70 [ 11.489326] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Wei Wang fixed a part of these CDG-malloc issues with commit c12014440750 ("tcp: memset ca_priv data to 0 properly"). This patch here fixes the listener-scenario: We make sure that listeners setting the congestion-control through setsockopt won't initialize it (thus CDG never allocates on listeners). For those who use AF_UNSPEC to reuse a socket, tcp_disconnect() is changed to cleanup afterwards. (The issue can be reproduced at least down to v4.4.x.) Cc: Wei Wang <weiwan@google.com> Cc: Eric Dumazet <edumazet@google.com> Fixes: 2b0a8c9eee81 ("tcp: add CDG congestion control") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1ca0fafd |
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01-Jul-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: allow changing MD5 keys in all socket states This essentially reverts commit 721230326891 ("tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets") Mathieu reported that many vendors BGP implementations can actually switch TCP MD5 on established flows. Quoting Mathieu : Here is a list of a few network vendors along with their behavior with respect to TCP MD5: - Cisco: Allows for password to be changed, but within the hold-down timer (~180 seconds). - Juniper: When password is initially set on active connection it will reset, but after that any subsequent password changes no network resets. - Nokia: No notes on if they flap the tcp connection or not. - Ericsson/RedBack: Allows for 2 password (old/new) to co-exist until both sides are ok with new passwords. - Meta-Switch: Expects the password to be set before a connection is attempted, but no further info on whether they reset the TCP connection on a change. - Avaya: Disable the neighbor, then set password, then re-enable. - Zebos: Would normally allow the change when socket connected. We can revert my prior change because commit 9424e2e7ad93 ("tcp: md5: fix potential overestimation of TCP option space") removed the leak of 4 kernel bytes to the wire that was the main reason for my patch. While doing my investigations, I found a bug when a MD5 key is changed, leading to these commits that stable teams want to consider before backporting this revert : Commit 6a2febec338d ("tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key()") Commit e6ced831ef11 ("tcp: md5: refine tcp_md5_do_add()/tcp_md5_hash_key() barriers") Fixes: 721230326891 "tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets" Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e6ced831 |
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01-Jul-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: refine tcp_md5_do_add()/tcp_md5_hash_key() barriers My prior fix went a bit too far, according to Herbert and Mathieu. Since we accept that concurrent TCP MD5 lookups might see inconsistent keys, we can use READ_ONCE()/WRITE_ONCE() instead of smp_rmb()/smp_wmb() Clearing all key->key[] is needed to avoid possible KMSAN reports, if key->keylen is increased. Since tcp_md5_do_add() is not fast path, using __GFP_ZERO to clear all struct tcp_md5sig_key is simpler. data_race() was added in linux-5.8 and will prevent KCSAN reports, this can safely be removed in stable backports, if data_race() is not yet backported. v2: use data_race() both in tcp_md5_hash_key() and tcp_md5_do_add() Fixes: 6a2febec338d ("tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Marco Elver <elver@google.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6a2febec |
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30-Jun-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key() MD5 keys are read with RCU protection, and tcp_md5_do_add() might update in-place a prior key. Normally, typical RCU updates would allocate a new piece of memory. In this case only key->key and key->keylen might be updated, and we do not care if an incoming packet could see the old key, the new one, or some intermediate value, since changing the key on a live flow is known to be problematic anyway. We only want to make sure that in the case key->keylen is changed, cpus in tcp_md5_hash_key() wont try to use uninitialized data, or crash because key->keylen was read twice to feed sg_init_one() and ahash_request_set_crypt() Fixes: 9ea88a153001 ("tcp: md5: check md5 signature without socket lock") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
aad4a0a9 |
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20-Jun-2020 |
Dmitry Yakunin <zeil@yandex-team.ru> |
tcp: Expose tcp_sock_set_keepidle_locked This is preparation for usage in bpf_setsockopt. v2: - remove redundant EXPORT_SYMBOL (Alexei Starovoitov) Signed-off-by: Dmitry Yakunin <zeil@yandex-team.ru> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200620153052.9439-2-zeil@yandex-team.ru
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#
3e4e28c5 |
|
08-Jun-2020 |
Michel Lespinasse <walken@google.com> |
mmap locking API: convert mmap_sem API comments Convert comments that reference old mmap_sem APIs to reference corresponding new mmap locking APIs instead. Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-12-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
d8ed45c5 |
|
08-Jun-2020 |
Michel Lespinasse <walken@google.com> |
mmap locking API: use coccinelle to convert mmap_sem rwsem call sites This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
3763a24c |
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07-Jun-2020 |
Arjun Roy <arjunroy@google.com> |
net-zerocopy: use vm_insert_pages() for tcp rcv zerocopy Use vm_insert_pages() for tcp receive zerocopy. Spin lock cycles (as reported by perf) drop from a couple of percentage points to a fraction of a percent. This results in a roughly 6% increase in efficiency, measured roughly as zerocopy receive count divided by CPU utilization. The intention of this patchset is to reduce atomic ops for tcp zerocopy receives, which normally hits the same spinlock multiple times consecutively. [akpm@linux-foundation.org: suppress gcc-7.2.0 warning] Link: http://lkml.kernel.org/r/20200128025958.43490-3-arjunroy.kdev@gmail.com Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Cc: David Miller <davem@davemloft.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
480aeb96 |
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27-May-2020 |
Christoph Hellwig <hch@lst.de> |
tcp: add tcp_sock_set_keepcnt Add a helper to directly set the TCP_KEEPCNT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d41ecaac |
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27-May-2020 |
Christoph Hellwig <hch@lst.de> |
tcp: add tcp_sock_set_keepintvl Add a helper to directly set the TCP_KEEPINTVL sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
71c48eb8 |
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27-May-2020 |
Christoph Hellwig <hch@lst.de> |
tcp: add tcp_sock_set_keepidle Add a helper to directly set the TCP_KEEP_IDLE sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c488aead |
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27-May-2020 |
Christoph Hellwig <hch@lst.de> |
tcp: add tcp_sock_set_user_timeout Add a helper to directly set the TCP_USER_TIMEOUT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
557eadfc |
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27-May-2020 |
Christoph Hellwig <hch@lst.de> |
tcp: add tcp_sock_set_syncnt Add a helper to directly set the TCP_SYNCNT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ddd061b8 |
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27-May-2020 |
Christoph Hellwig <hch@lst.de> |
tcp: add tcp_sock_set_quickack Add a helper to directly set the TCP_QUICKACK sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
12abc5ee |
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27-May-2020 |
Christoph Hellwig <hch@lst.de> |
tcp: add tcp_sock_set_nodelay Add a helper to directly set the TCP_NODELAY sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Sagi Grimberg <sagi@grimberg.me> Acked-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
db10538a |
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27-May-2020 |
Christoph Hellwig <hch@lst.de> |
tcp: add tcp_sock_set_cork Add a helper to directly set the TCP_CORK sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e776af60 |
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14-May-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: fix error recovery in tcp_zerocopy_receive() If user provides wrong virtual address in TCP_ZEROCOPY_RECEIVE operation we want to return -EINVAL error. But depending on zc->recv_skip_hint content, we might return -EIO error if the socket has SOCK_DONE set. Make sure to return -EINVAL in this case. BUG: KMSAN: uninit-value in tcp_zerocopy_receive net/ipv4/tcp.c:1833 [inline] BUG: KMSAN: uninit-value in do_tcp_getsockopt+0x4494/0x6320 net/ipv4/tcp.c:3685 CPU: 1 PID: 625 Comm: syz-executor.0 Not tainted 5.7.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 tcp_zerocopy_receive net/ipv4/tcp.c:1833 [inline] do_tcp_getsockopt+0x4494/0x6320 net/ipv4/tcp.c:3685 tcp_getsockopt+0xf8/0x1f0 net/ipv4/tcp.c:3728 sock_common_getsockopt+0x13f/0x180 net/core/sock.c:3131 __sys_getsockopt+0x533/0x7b0 net/socket.c:2177 __do_sys_getsockopt net/socket.c:2192 [inline] __se_sys_getsockopt+0xe1/0x100 net/socket.c:2189 __x64_sys_getsockopt+0x62/0x80 net/socket.c:2189 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c829 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1deeb72c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00000000004e01e0 RCX: 000000000045c829 RDX: 0000000000000023 RSI: 0000000000000006 RDI: 0000000000000009 RBP: 000000000078bf00 R08: 0000000020000200 R09: 0000000000000000 R10: 00000000200001c0 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000001d8 R14: 00000000004d3038 R15: 00007f1deeb736d4 Local variable ----zc@do_tcp_getsockopt created at: do_tcp_getsockopt+0x1a74/0x6320 net/ipv4/tcp.c:3670 do_tcp_getsockopt+0x1a74/0x6320 net/ipv4/tcp.c:3670 Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
24adbc16 |
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12-May-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: fix SO_RCVLOWAT hangs with fat skbs We autotune rcvbuf whenever SO_RCVLOWAT is set to account for 100% overhead in tcp_set_rcvlowat() This works well when skb->len/skb->truesize ratio is bigger than 0.5 But if we receive packets with small MSS, we can end up in a situation where not enough bytes are available in the receive queue to satisfy RCVLOWAT setting. As our sk_rcvbuf limit is hit, we send zero windows in ACK packets, preventing remote peer from sending more data. Even autotuning does not help, because it only triggers at the time user process drains the queue. If no EPOLLIN is generated, this can not happen. Note poll() has a similar issue, after commit c7004482e8dc ("tcp: Respect SO_RCVLOWAT in tcp_poll().") Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cc4de047 |
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08-May-2020 |
Kelly Littlepage <kelly@onechronos.com> |
net: tcp: fix rx timestamp behavior for tcp_recvmsg The stated intent of the original commit is to is to "return the timestamp corresponding to the highest sequence number data returned." The current implementation returns the timestamp for the last byte of the last fully read skb, which is not necessarily the last byte in the recv buffer. This patch converts behavior to the original definition, and to the behavior of the previous draft versions of commit 98aaa913b4ed ("tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg") which also match this behavior. Fixes: 98aaa913b4ed ("tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg") Co-developed-by: Iris Liu <iris@onechronos.com> Signed-off-by: Iris Liu <iris@onechronos.com> Signed-off-by: Kelly Littlepage <kelly@onechronos.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
f0628c52 |
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24-Apr-2020 |
Cambda Zhu <cambda@linux.alibaba.com> |
net: Replace the limit of TCP_LINGER2 with TCP_FIN_TIMEOUT_MAX This patch changes the behavior of TCP_LINGER2 about its limit. The sysctl_tcp_fin_timeout used to be the limit of TCP_LINGER2 but now it's only the default value. A new macro named TCP_FIN_TIMEOUT_MAX is added as the limit of TCP_LINGER2, which is 2 minutes. Since TCP_LINGER2 used sysctl_tcp_fin_timeout as the default value and the limit in the past, the system administrator cannot set the default value for most of sockets and let some sockets have a greater timeout. It might be a mistake that let the sysctl to be the limit of the TCP_LINGER2. Maybe we can add a new sysctl to set the max of TCP_LINGER2, but FIN-WAIT-2 timeout is usually no need to be too long and 2 minutes are legal considering TCP specs. Changes in v3: - Remove the new socket option and change the TCP_LINGER2 behavior so that the timeout can be set to value between sysctl_tcp_fin_timeout and 2 minutes. Changes in v2: - Add int overflow check for the new socket option. Changes in v1: - Add a new socket option to set timeout greater than sysctl_tcp_fin_timeout. Signed-off-by: Cambda Zhu <cambda@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6cd6cbf5 |
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18-Mar-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: repair: fix TCP_QUEUE_SEQ implementation When application uses TCP_QUEUE_SEQ socket option to change tp->rcv_next, we must also update tp->copied_seq. Otherwise, stuff relying on tcp_inq() being precise can eventually be confused. For example, tcp_zerocopy_receive() might crash because it does not expect tcp_recv_skb() to return NULL. We could add tests in various places to fix the issue, or simply make sure tcp_inq() wont return a random value, and leave fast path as it is. Note that this fixes ioctl(fd, SIOCINQ, &val) at the same time. Fixes: ee9952831cfd ("tcp: Initial repair mode") Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a8eceea8 |
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12-Mar-2020 |
Joe Perches <joe@perches.com> |
inet: Use fallthrough; Convert the various uses of fallthrough comments to fallthrough; Done via script Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/ And by hand: net/ipv6/ip6_fib.c has a fallthrough comment outside of an #ifdef block that causes gcc to emit a warning if converted in-place. So move the new fallthrough; inside the containing #ifdef/#endif too. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e08ab0b3 |
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09-Mar-2020 |
Yousuk Seung <ysseung@google.com> |
tcp: add bytes not sent to SCM_TIMESTAMPING_OPT_STATS Add TCP_NLA_BYTES_NOTSENT to SCM_TIMESTAMPING_OPT_STATS that reports bytes in the write queue but not sent. This is the same metric as what is exported with tcp_info.tcpi_notsent_bytes. Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0b7f41f6 |
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25-Feb-2020 |
Arjun Roy <arjunroy@google.com> |
tcp-zerocopy: Update returned getsockopt() optlen. TCP receive zerocopy currently does not update the returned optlen for getsockopt() if the user passed in a larger than expected value. Thus, userspace cannot properly determine if all the fields are set in the passed-in struct. This patch sets the optlen for this case before returning, in keeping with the expected operation of getsockopt(). Fixes: c8856c051454 ("tcp-zerocopy: Return inq along with tcp receive zerocopy.") Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
33946518 |
|
14-Feb-2020 |
Arjun Roy <arjunroy@google.com> |
tcp-zerocopy: Return sk_err (if set) along with tcp receive zerocopy. This patchset is intended to reduce the number of extra system calls imposed by TCP receive zerocopy. For ping-pong RPC style workloads, this patchset has demonstrated a system call reduction of about 30% when coupled with userspace changes. For applications using epoll, returning sk_err along with the result of tcp receive zerocopy could remove the need to call recvmsg()=-EAGAIN after a spurious wakeup. Consider a multi-threaded application using epoll. A thread may awaken with EPOLLIN but another thread may already be reading. The spuriously-awoken thread does not necessarily know that another thread 'won'; rather, it may be possible that it was woken up due to the presence of an error if there is no data. A zerocopy read receiving 0 bytes thus would need to be followed up by recvmsg to be sure. Instead, we return sk_err directly with zerocopy, so the application can avoid this extra system call. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c8856c05 |
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14-Feb-2020 |
Arjun Roy <arjunroy@google.com> |
tcp-zerocopy: Return inq along with tcp receive zerocopy. This patchset is intended to reduce the number of extra system calls imposed by TCP receive zerocopy. For ping-pong RPC style workloads, this patchset has demonstrated a system call reduction of about 30% when coupled with userspace changes. For applications using edge-triggered epoll, returning inq along with the result of tcp receive zerocopy could remove the need to call recvmsg()=-EAGAIN after a successful zerocopy. Generally speaking, since normally we would need to perform a recvmsg() call for every successful small RPC read via TCP receive zerocopy, returning inq can reduce the number of system calls performed by approximately half. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
784f8344 |
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31-Jan-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: clear tp->segs_{in|out} in tcp_disconnect() tp->segs_in and tp->segs_out need to be cleared in tcp_disconnect(). tcp_disconnect() is rarely used, but it is worth fixing it. Fixes: 2efd055c53c0 ("tcp: add tcpi_segs_in and tcpi_segs_out to tcp_info") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Marcelo Ricardo Leitner <mleitner@redhat.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
db7ffee6 |
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31-Jan-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: clear tp->data_segs{in|out} in tcp_disconnect() tp->data_segs_in and tp->data_segs_out need to be cleared in tcp_disconnect(). tcp_disconnect() is rarely used, but it is worth fixing it. Fixes: a44d6eacdaf5 ("tcp: Add RFC4898 tcpEStatsPerfDataSegsOut/In") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
2fbdd562 |
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31-Jan-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: clear tp->delivered in tcp_disconnect() tp->delivered needs to be cleared in tcp_disconnect(). tcp_disconnect() is rarely used, but it is worth fixing it. Fixes: ddf1af6fa00e ("tcp: new delivery accounting") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
c13c48c0 |
|
31-Jan-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: clear tp->total_retrans in tcp_disconnect() total_retrans needs to be cleared in tcp_disconnect(). tcp_disconnect() is rarely used, but it is worth fixing it. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: SeongJae Park <sjpark@amazon.de> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
32efcc06 |
|
24-Jan-2020 |
Abdul Kabbani <akabbani@google.com> |
tcp: export count for rehash attempts Using IPv6 flow-label to swiftly route around avoid congested or disconnected network path can greatly improve TCP reliability. This patch adds SNMP counters and a OPT_STATS counter to track both host-level and connection-level statistics. Network administrators can use these counters to evaluate the impact of this new ability better. Export count for rehash attempts to 1) two SNMP counters: TcpTimeoutRehash (rehash due to timeouts), and TcpDuplicateDataRehash (rehash due to receiving duplicate packets) 2) Timestamping API SOF_TIMESTAMPING_OPT_STATS. Signed-off-by: Abdul Kabbani <akabbani@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Kevin(Yudong) Yang <yyd@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f870fa0b |
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21-Jan-2020 |
Mat Martineau <mathew.j.martineau@linux.intel.com> |
mptcp: Add MPTCP socket stubs Implements the infrastructure for MPTCP sockets. MPTCP sockets open one in-kernel TCP socket per subflow. These subflow sockets are only managed by the MPTCP socket that owns them and are not visible from userspace. This commit allows a userspace program to open an MPTCP socket with: sock = socket(AF_INET, SOCK_STREAM, IPPROTO_MPTCP); The resulting socket is simply a wrapper around a single regular TCP socket, without any of the MPTCP protocol implemented over the wire. Co-developed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Florian Westphal <fw@strlen.de> Co-developed-by: Peter Krystad <peter.krystad@linux.intel.com> Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com> Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2bec445f |
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22-Jan-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: do not leave dangling pointers in tp->highest_sack Latest commit 853697504de0 ("tcp: Fix highest_sack and highest_sack_seq") apparently allowed syzbot to trigger various crashes in TCP stack [1] I believe this commit only made things easier for syzbot to find its way into triggering use-after-frees. But really the bugs could lead to bad TCP behavior or even plain crashes even for non malicious peers. I have audited all calls to tcp_rtx_queue_unlink() and tcp_rtx_queue_unlink_and_free() and made sure tp->highest_sack would be updated if we are removing from rtx queue the skb that tp->highest_sack points to. These updates were missing in three locations : 1) tcp_clean_rtx_queue() [This one seems quite serious, I have no idea why this was not caught earlier] 2) tcp_rtx_queue_purge() [Probably not a big deal for normal operations] 3) tcp_send_synack() [Probably not a big deal for normal operations] [1] BUG: KASAN: use-after-free in tcp_highest_sack_seq include/net/tcp.h:1864 [inline] BUG: KASAN: use-after-free in tcp_highest_sack_seq include/net/tcp.h:1856 [inline] BUG: KASAN: use-after-free in tcp_check_sack_reordering+0x33c/0x3a0 net/ipv4/tcp_input.c:891 Read of size 4 at addr ffff8880a488d068 by task ksoftirqd/1/16 CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.5.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:639 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:134 tcp_highest_sack_seq include/net/tcp.h:1864 [inline] tcp_highest_sack_seq include/net/tcp.h:1856 [inline] tcp_check_sack_reordering+0x33c/0x3a0 net/ipv4/tcp_input.c:891 tcp_try_undo_partial net/ipv4/tcp_input.c:2730 [inline] tcp_fastretrans_alert+0xf74/0x23f0 net/ipv4/tcp_input.c:2847 tcp_ack+0x2577/0x5bf0 net/ipv4/tcp_input.c:3710 tcp_rcv_established+0x6dd/0x1e90 net/ipv4/tcp_input.c:5706 tcp_v4_do_rcv+0x619/0x8d0 net/ipv4/tcp_ipv4.c:1619 tcp_v4_rcv+0x307f/0x3b40 net/ipv4/tcp_ipv4.c:2001 ip_protocol_deliver_rcu+0x5a/0x880 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x23b/0x380 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x1e9/0x520 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x1db/0x2f0 net/ipv4/ip_input.c:428 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_rcv+0xe8/0x3f0 net/ipv4/ip_input.c:538 __netif_receive_skb_one_core+0x113/0x1a0 net/core/dev.c:5148 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5262 process_backlog+0x206/0x750 net/core/dev.c:6093 napi_poll net/core/dev.c:6530 [inline] net_rx_action+0x508/0x1120 net/core/dev.c:6598 __do_softirq+0x262/0x98c kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:603 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 10091: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:521 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slab.c:3263 [inline] kmem_cache_alloc_node+0x138/0x740 mm/slab.c:3575 __alloc_skb+0xd5/0x5e0 net/core/skbuff.c:198 alloc_skb_fclone include/linux/skbuff.h:1099 [inline] sk_stream_alloc_skb net/ipv4/tcp.c:875 [inline] sk_stream_alloc_skb+0x113/0xc90 net/ipv4/tcp.c:852 tcp_sendmsg_locked+0xcf9/0x3470 net/ipv4/tcp.c:1282 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1432 inet_sendmsg+0x9e/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 __sys_sendto+0x262/0x380 net/socket.c:1998 __do_sys_sendto net/socket.c:2010 [inline] __se_sys_sendto net/socket.c:2006 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:2006 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 10095: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:335 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483 __cache_free mm/slab.c:3426 [inline] kmem_cache_free+0x86/0x320 mm/slab.c:3694 kfree_skbmem+0x178/0x1c0 net/core/skbuff.c:645 __kfree_skb+0x1e/0x30 net/core/skbuff.c:681 sk_eat_skb include/net/sock.h:2453 [inline] tcp_recvmsg+0x1252/0x2930 net/ipv4/tcp.c:2166 inet_recvmsg+0x136/0x610 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:886 [inline] sock_recvmsg net/socket.c:904 [inline] sock_recvmsg+0xce/0x110 net/socket.c:900 __sys_recvfrom+0x1ff/0x350 net/socket.c:2055 __do_sys_recvfrom net/socket.c:2073 [inline] __se_sys_recvfrom net/socket.c:2069 [inline] __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:2069 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a488d040 which belongs to the cache skbuff_fclone_cache of size 456 The buggy address is located 40 bytes inside of 456-byte region [ffff8880a488d040, ffff8880a488d208) The buggy address belongs to the page: page:ffffea0002922340 refcount:1 mapcount:0 mapping:ffff88821b057000 index:0x0 raw: 00fffe0000000200 ffffea00022a5788 ffffea0002624a48 ffff88821b057000 raw: 0000000000000000 ffff8880a488d040 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a488cf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a488cf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a488d000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff8880a488d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a488d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 853697504de0 ("tcp: Fix highest_sack and highest_sack_seq") Fixes: 50895b9de1d3 ("tcp: highest_sack fix") Fixes: 737ff314563c ("tcp: use sequence distance to detect reordering") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Cambda Zhu <cambda@linux.alibaba.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bfe02b9f |
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20-Jan-2020 |
Theodore Dubois <tblodt@icloud.com> |
tcp: remove redundant assigment to snd_cwnd Not sure how this got in here. git blame says the second assignment was added in 3a9a57f6, but that commit also removed the first assignment. Signed-off-by: Theodore Dubois <tblodt@icloud.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
35b2c321 |
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09-Jan-2020 |
Mat Martineau <mathew.j.martineau@linux.intel.com> |
tcp: Export TCP functions and ops struct MPTCP will make use of tcp_send_mss() and tcp_push() when sending data to specific TCP subflows. tcp_request_sock_ipvX_ops and ipvX_specific will be referenced during TCP subflow creation. Co-developed-by: Peter Krystad <peter.krystad@linux.intel.com> Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0e627190 |
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15-Dec-2019 |
Arjun Roy <arjunroy@google.com> |
tcp: Set rcv zerocopy hint correctly if skb last frag is < PAGE_SIZE At present, if the last frag of paged data in a skb has < PAGE_SIZE data, we compute the recv_skip_hint as being equal to the size of that frag and the entire next skb. Instead, just return the runt frag size as the hint. recv_skip_hint is used by the application to skip over bytes that can not be mmaped, so returning a too big chunk is pessimistic and forces more bytes to be copied. Signed-off-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
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#
216808c6 |
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12-Dec-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: refine rule to allow EPOLLOUT generation under mem pressure At the time commit ce5ec440994b ("tcp: ensure epoll edge trigger wakeup when write queue is empty") was added to the kernel, we still had a single write queue, combining rtx and write queues. Once we moved the rtx queue into a separate rb-tree, testing if sk_write_queue is empty has been suboptimal. Indeed, if we have packets in the rtx queue, we probably want to delay the EPOLLOUT generation at the time incoming packets will free them, making room, but more importantly avoiding flooding application with EPOLLOUT events. Solution is to use tcp_rtx_and_write_queues_empty() helper. Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
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#
5000b28b |
|
09-Dec-2019 |
Kuniyuki Iwashima <kuni1840@gmail.com> |
tcp: Cleanup duplicate initialization of sk->sk_state. When a TCP socket is created, sk->sk_state is initialized twice as TCP_CLOSE in sock_init_data() and tcp_init_sock(). The tcp_init_sock() is always called after the sock_init_data(), so it is not necessary to update sk->sk_state in the tcp_init_sock(). Before v2.1.8, the code of the two functions was in the inet_create(). In the patch of v2.1.8, the tcp_v4/v6_init_sock() were added and the code of initialization of sk->state was duplicated. Signed-off-by: Kuniyuki Iwashima <kuni1840@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c593642c |
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09-Dec-2019 |
Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com> |
treewide: Use sizeof_field() macro Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except at places where these are defined. Later patches will remove the unused definition of FIELD_SIZEOF(). This patch is generated using following script: EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h" git grep -l -e "\bFIELD_SIZEOF\b" | while read file; do if [[ "$file" =~ $EXCLUDE_FILES ]]; then continue fi sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file; done Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com> Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: David Miller <davem@davemloft.net> # for net
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#
df1b4ba9 |
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25-Oct-2019 |
Arnd Bergmann <arnd@arndb.de> |
y2038: socket: use __kernel_old_timespec instead of timespec The 'timespec' type definition and helpers like ktime_to_timespec() or timespec64_to_timespec() should no longer be used in the kernel so we can remove them and avoid introducing y2038 issues in new code. Change the socket code that needs to pass a timespec to user space for backward compatibility to use __kernel_old_timespec instead. This type has the same layout but with a clearer defined name. Slightly reformat tcp_recv_timestamp() for consistency after the removal of timespec64_to_timespec(). Acked-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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#
a5a7daa5 |
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06-Nov-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: fix data-race in tcp_recvmsg() Reading tp->recvmsg_inq after socket lock is released raises a KCSAN warning [1] Replace has_tss & has_cmsg by cmsg_flags and make sure to not read tp->recvmsg_inq a second time. [1] BUG: KCSAN: data-race in tcp_chrono_stop / tcp_recvmsg write to 0xffff888126adef24 of 2 bytes by interrupt on cpu 0: tcp_chrono_set net/ipv4/tcp_output.c:2309 [inline] tcp_chrono_stop+0x14c/0x280 net/ipv4/tcp_output.c:2338 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3165 [inline] tcp_ack+0x274f/0x3170 net/ipv4/tcp_input.c:3688 tcp_rcv_established+0x37e/0xf50 net/ipv4/tcp_input.c:5696 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1561 tcp_v4_rcv+0x19dc/0x1bb0 net/ipv4/tcp_ipv4.c:1942 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5214 napi_skb_finish net/core/dev.c:5677 [inline] napi_gro_receive+0x28f/0x330 net/core/dev.c:5710 read to 0xffff888126adef25 of 1 bytes by task 7275 on cpu 1: tcp_recvmsg+0x77b/0x1a30 net/ipv4/tcp.c:2187 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_recvmsg+0x92/0xb0 net/socket.c:885 sock_read_iter+0x15f/0x1e0 net/socket.c:967 call_read_iter include/linux/fs.h:1889 [inline] new_sync_read+0x389/0x4f0 fs/read_write.c:414 __vfs_read+0xb1/0xc0 fs/read_write.c:427 vfs_read fs/read_write.c:461 [inline] vfs_read+0x143/0x2c0 fs/read_write.c:446 ksys_read+0xd5/0x1b0 fs/read_write.c:587 __do_sys_read fs/read_write.c:597 [inline] __se_sys_read fs/read_write.c:595 [inline] __x64_sys_read+0x4c/0x60 fs/read_write.c:595 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7275 Comm: sshd Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: b75eba76d3d7 ("tcp: send in-queue bytes in cmsg upon read") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9ed498c6 |
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06-Nov-2019 |
Eric Dumazet <edumazet@google.com> |
net: silence data-races on sk_backlog.tail sk->sk_backlog.tail might be read without holding the socket spinlock, we need to add proper READ_ONCE()/WRITE_ONCE() to silence the warnings. KCSAN reported : BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg write to 0xffff8881265109f8 of 8 bytes by interrupt on cpu 1: __sk_add_backlog include/net/sock.h:907 [inline] sk_add_backlog include/net/sock.h:938 [inline] tcp_add_backlog+0x476/0xce0 net/ipv4/tcp_ipv4.c:1759 tcp_v4_rcv+0x1a70/0x1bd0 net/ipv4/tcp_ipv4.c:1947 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:4929 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5043 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5133 napi_skb_finish net/core/dev.c:5596 [inline] napi_gro_receive+0x28f/0x330 net/core/dev.c:5629 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061 virtnet_receive drivers/net/virtio_net.c:1323 [inline] virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428 napi_poll net/core/dev.c:6311 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6379 __do_softirq+0x115/0x33f kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0xbb/0xe0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] do_IRQ+0xa6/0x180 arch/x86/kernel/irq.c:263 ret_from_intr+0x0/0x19 native_safe_halt+0xe/0x10 arch/x86/kernel/paravirt.c:71 arch_cpu_idle+0x1f/0x30 arch/x86/kernel/process.c:571 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1af/0x280 kernel/sched/idle.c:263 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355 start_secondary+0x208/0x260 arch/x86/kernel/smpboot.c:264 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 read to 0xffff8881265109f8 of 8 bytes by task 8057 on cpu 0: tcp_recvmsg+0x46e/0x1b40 net/ipv4/tcp.c:2050 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_recvmsg+0x92/0xb0 net/socket.c:885 sock_read_iter+0x15f/0x1e0 net/socket.c:967 call_read_iter include/linux/fs.h:1889 [inline] new_sync_read+0x389/0x4f0 fs/read_write.c:414 __vfs_read+0xb1/0xc0 fs/read_write.c:427 vfs_read fs/read_write.c:461 [inline] vfs_read+0x143/0x2c0 fs/read_write.c:446 ksys_read+0xd5/0x1b0 fs/read_write.c:587 __do_sys_read fs/read_write.c:597 [inline] __se_sys_read fs/read_write.c:595 [inline] __x64_sys_read+0x4c/0x60 fs/read_write.c:595 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 8057 Comm: syz-fuzzer Not tainted 5.4.0-rc6+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
099ecf59 |
|
05-Nov-2019 |
Eric Dumazet <edumazet@google.com> |
net: annotate lockless accesses to sk->sk_max_ack_backlog sk->sk_max_ack_backlog can be read without any lock being held at least in TCP/DCCP cases. We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing and/or potential KCSAN warnings. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
288efe86 |
|
05-Nov-2019 |
Eric Dumazet <edumazet@google.com> |
net: annotate lockless accesses to sk->sk_ack_backlog sk->sk_ack_backlog can be read without any lock being held. We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing and/or potential KCSAN warnings. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3f926af3 |
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23-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
net: use skb_queue_empty_lockless() in busy poll contexts Busy polling usually runs without locks. Let's use skb_queue_empty_lockless() instead of skb_queue_empty() Also uses READ_ONCE() in __skb_try_recv_datagram() to address a similar potential problem. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3ef7cf57 |
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23-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
net: use skb_queue_empty_lockless() in poll() handlers Many poll() handlers are lockless. Using skb_queue_empty_lockless() instead of skb_queue_empty() is more appropriate. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
48027478 |
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23-Oct-2019 |
Jason Baron <jbaron@akamai.com> |
tcp: add TCP_INFO status for failed client TFO The TCPI_OPT_SYN_DATA bit as part of tcpi_options currently reports whether or not data-in-SYN was ack'd on both the client and server side. We'd like to gather more information on the client-side in the failure case in order to indicate the reason for the failure. This can be useful for not only debugging TFO, but also for creating TFO socket policies. For example, if a middle box removes the TFO option or drops a data-in-SYN, we can can detect this case, and turn off TFO for these connections saving the extra retransmits. The newly added tcpi_fastopen_client_fail status is 2 bits and has the following 4 states: 1) TFO_STATUS_UNSPEC Catch-all state which includes when TFO is disabled via black hole detection, which is indicated via LINUX_MIB_TCPFASTOPENBLACKHOLE. 2) TFO_COOKIE_UNAVAILABLE If TFO_CLIENT_NO_COOKIE mode is off, this state indicates that no cookie is available in the cache. 3) TFO_DATA_NOT_ACKED Data was sent with SYN, we received a SYN/ACK but it did not cover the data portion. Cookie is not accepted by server because the cookie may be invalid or the server may be overloaded. 4) TFO_SYN_RETRANSMITTED Data was sent with SYN, we received a SYN/ACK which did not cover the data after at least 1 additional SYN was sent (without data). It may be the case that a middle-box is dropping data-in-SYN packets. Thus, it would be more efficient to not use TFO on this connection to avoid extra retransmits during connection establishment. These new fields do not cover all the cases where TFO may fail, but other failures, such as SYN/ACK + data being dropped, will result in the connection not becoming established. And a connection blackhole after session establishment shows up as a stalled connection. Signed-off-by: Jason Baron <jbaron@akamai.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Christoph Paasch <cpaasch@apple.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cab209e5 |
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14-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: fix a possible lockdep splat in tcp_done() syzbot found that if __inet_inherit_port() returns an error, we call tcp_done() after inet_csk_prepare_forced_close(), meaning the socket lock is no longer held. We might fix this in a different way in net-next, but for 5.4 it seems safer to relax the lockdep check. Fixes: d983ea6f16b8 ("tcp: add rcu protection around tp->fastopen_rsk") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c208bdb9 |
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10-Oct-2019 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: improve recv_skip_hint for tcp_zerocopy_receive tcp_zerocopy_receive() rounds down the zc->length a multiple of PAGE_SIZE. This results in two issues: - tcp_zerocopy_receive sets recv_skip_hint to the length of the receive queue if the zc->length input is smaller than the PAGE_SIZE, even though the data in receive queue could be zerocopied. - tcp_zerocopy_receive would set recv_skip_hint of 0, in cases where we have a little bit of data after the perfectly-sized packets. To fix these issues, do not store the rounded down value in zc->length. Round down the length passed to zap_page_range(), and return min(inq, zc->length) when the zap_range is 0. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ab4e846a |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate sk->sk_wmem_queued lockless reads For the sake of tcp_poll(), there are few places where we fetch sk->sk_wmem_queued while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. sk_wmem_queued_add() helper is added so that we can in the future convert to ADD_ONCE() or equivalent if/when available. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e292f05e |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate sk->sk_sndbuf lockless reads For the sake of tcp_poll(), there are few places where we fetch sk->sk_sndbuf while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that other transports probably need similar fixes. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ebb3b78d |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate sk->sk_rcvbuf lockless reads For the sake of tcp_poll(), there are few places where we fetch sk->sk_rcvbuf while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that other transports probably need similar fixes. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d9b55bf7 |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate tp->urg_seq lockless reads There two places where we fetch tp->urg_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write side use corresponding WRITE_ONCE() to avoid store-tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e0d694d6 |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate tp->snd_nxt lockless reads There are few places where we fetch tp->snd_nxt while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0f317464 |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate tp->write_seq lockless reads There are few places where we fetch tp->write_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7db48e98 |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate tp->copied_seq lockless reads There are few places where we fetch tp->copied_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that tcp_inq_hint() was already using READ_ONCE(tp->copied_seq) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
dba7d9b8 |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate tp->rcv_nxt lockless reads There are few places where we fetch tp->rcv_nxt while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that tcp_inq_hint() was already using READ_ONCE(tp->rcv_nxt) syzbot reported : BUG: KCSAN: data-race in tcp_poll / tcp_queue_rcv write to 0xffff888120425770 of 4 bytes by interrupt on cpu 0: tcp_rcv_nxt_update net/ipv4/tcp_input.c:3365 [inline] tcp_queue_rcv+0x180/0x380 net/ipv4/tcp_input.c:4638 tcp_rcv_established+0xbf1/0xf50 net/ipv4/tcp_input.c:5616 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1542 tcp_v4_rcv+0x1a03/0x1bf0 net/ipv4/tcp_ipv4.c:1923 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208 napi_skb_finish net/core/dev.c:5671 [inline] napi_gro_receive+0x28f/0x330 net/core/dev.c:5704 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061 read to 0xffff888120425770 of 4 bytes by task 7254 on cpu 1: tcp_stream_is_readable net/ipv4/tcp.c:480 [inline] tcp_poll+0x204/0x6b0 net/ipv4/tcp.c:554 sock_poll+0xed/0x250 net/socket.c:1256 vfs_poll include/linux/poll.h:90 [inline] ep_item_poll.isra.0+0x90/0x190 fs/eventpoll.c:892 ep_send_events_proc+0x113/0x5c0 fs/eventpoll.c:1749 ep_scan_ready_list.constprop.0+0x189/0x500 fs/eventpoll.c:704 ep_send_events fs/eventpoll.c:1793 [inline] ep_poll+0xe3/0x900 fs/eventpoll.c:1930 do_epoll_wait+0x162/0x180 fs/eventpoll.c:2294 __do_sys_epoll_pwait fs/eventpoll.c:2325 [inline] __se_sys_epoll_pwait fs/eventpoll.c:2311 [inline] __x64_sys_epoll_pwait+0xcd/0x170 fs/eventpoll.c:2311 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7254 Comm: syz-fuzzer Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d983ea6f |
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10-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: add rcu protection around tp->fastopen_rsk Both tcp_v4_err() and tcp_v6_err() do the following operations while they do not own the socket lock : fastopen = tp->fastopen_rsk; snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; The problem is that without appropriate barrier, the compiler might reload tp->fastopen_rsk and trigger a NULL deref. request sockets are protected by RCU, we can simply add the missing annotations and barriers to solve the issue. Fixes: 168a8f58059a ("tcp: TCP Fast Open Server - main code path") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
eac66402 |
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09-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
net: annotate sk->sk_rcvlowat lockless reads sock_rcvlowat() or int_sk_rcvlowat() might be called without the socket lock for example from tcp_poll(). Use READ_ONCE() to document the fact that other cpus might change sk->sk_rcvlowat under us and avoid KCSAN splats. Use WRITE_ONCE() on write sides too. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
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#
1f142c17 |
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09-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: annotate lockless access to tcp_memory_pressure tcp_memory_pressure is read without holding any lock, and its value could be changed on other cpus. Use READ_ONCE() to annotate these lockless reads. The write side is already using atomic ops. Fixes: b8da51ebb1aa ("tcp: introduce tcp_under_memory_pressure()") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
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#
3afb0961 |
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02-Oct-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: fix slab-out-of-bounds in tcp_zerocopy_receive() Apparently a refactoring patch brought a bug, that was caught by syzbot [1] Original code was correct, do not try to be smarter than the compiler :/ [1] BUG: KASAN: slab-out-of-bounds in tcp_zerocopy_receive net/ipv4/tcp.c:1807 [inline] BUG: KASAN: slab-out-of-bounds in do_tcp_getsockopt.isra.0+0x2c6c/0x3120 net/ipv4/tcp.c:3654 Read of size 4 at addr ffff8880943cf188 by task syz-executor.2/17508 CPU: 0 PID: 17508 Comm: syz-executor.2 Not tainted 5.3.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x17 mm/kasan/common.c:618 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 tcp_zerocopy_receive net/ipv4/tcp.c:1807 [inline] do_tcp_getsockopt.isra.0+0x2c6c/0x3120 net/ipv4/tcp.c:3654 tcp_getsockopt+0xbf/0xe0 net/ipv4/tcp.c:3680 sock_common_getsockopt+0x94/0xd0 net/core/sock.c:3098 __sys_getsockopt+0x16d/0x310 net/socket.c:2129 __do_sys_getsockopt net/socket.c:2144 [inline] __se_sys_getsockopt net/socket.c:2141 [inline] __x64_sys_getsockopt+0xbe/0x150 net/socket.c:2141 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 Fixes: d8e18a516f8f ("net: Use skb accessors in network core") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8f7baad7f |
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13-Sep-2019 |
Thomas Higdon <tph@fb.com> |
tcp: Add snd_wnd to TCP_INFO Neal Cardwell mentioned that snd_wnd would be useful for diagnosing TCP performance problems -- > (1) Usually when we're diagnosing TCP performance problems, we do so > from the sender, since the sender makes most of the > performance-critical decisions (cwnd, pacing, TSO size, TSQ, etc). > From the sender-side the thing that would be most useful is to see > tp->snd_wnd, the receive window that the receiver has advertised to > the sender. This serves the purpose of adding an additional __u32 to avoid the would-be hole caused by the addition of the tcpi_rcvi_ooopack field. Signed-off-by: Thomas Higdon <tph@fb.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f9af2dbb |
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13-Sep-2019 |
Thomas Higdon <tph@fb.com> |
tcp: Add TCP_INFO counter for packets received out-of-order For receive-heavy cases on the server-side, we want to track the connection quality for individual client IPs. This counter, similar to the existing system-wide TCPOFOQueue counter in /proc/net/netstat, tracks out-of-order packet reception. By providing this counter in TCP_INFO, it will allow understanding to what degree receive-heavy sockets are experiencing out-of-order delivery and packet drops indicating congestion. Please note that this is similar to the counter in NetBSD TCP_INFO, and has the same name. Also note that we avoid increasing the size of the tcp_sock struct by taking advantage of a hole. Signed-off-by: Thomas Higdon <tph@fb.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fdfc5c85 |
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26-Aug-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: remove empty skb from write queue in error cases Vladimir Rutsky reported stuck TCP sessions after memory pressure events. Edge Trigger epoll() user would never receive an EPOLLOUT notification allowing them to retry a sendmsg(). Jason tested the case of sk_stream_alloc_skb() returning NULL, but there are other paths that could lead both sendmsg() and sendpage() to return -1 (EAGAIN), with an empty skb queued on the write queue. This patch makes sure we remove this empty skb so that Jason code can detect that the queue is empty, and call sk->sk_write_space(sk) accordingly. Fixes: ce5ec440994b ("tcp: ensure epoll edge trigger wakeup when write queue is empty") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jason Baron <jbaron@akamai.com> Reported-by: Vladimir Rutsky <rutsky@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1a991488 |
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09-Aug-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: batch calls to sk_flush_backlog() Starting from commit d41a69f1d390 ("tcp: make tcp_sendmsg() aware of socket backlog") loopback flows got hurt, because for each skb sent, the socket receives an immediate ACK and sk_flush_backlog() causes extra work. Intent was to not let the backlog grow too much, but we went a bit too far. We can check the backlog every 16 skbs (about 1MB chunks) to increase TCP over loopback performance by about 15 % Note that the call to sk_flush_backlog() handles a single ACK, thanks to coalescing done on backlog, but cleans the 16 skbs found in rtx rb-tree. Reported-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
41477662 |
|
07-Aug-2019 |
Jakub Kicinski <kuba@kernel.org> |
net/tls: prevent skb_orphan() from leaking TLS plain text with offload sk_validate_xmit_skb() and drivers depend on the sk member of struct sk_buff to identify segments requiring encryption. Any operation which removes or does not preserve the original TLS socket such as skb_orphan() or skb_clone() will cause clear text leaks. Make the TCP socket underlying an offloaded TLS connection mark all skbs as decrypted, if TLS TX is in offload mode. Then in sk_validate_xmit_skb() catch skbs which have no socket (or a socket with no validation) and decrypted flag set. Note that CONFIG_SOCK_VALIDATE_XMIT, CONFIG_TLS_DEVICE and sk->sk_validate_xmit_skb are slightly interchangeable right now, they all imply TLS offload. The new checks are guarded by CONFIG_TLS_DEVICE because that's the option guarding the sk_buff->decrypted member. Second, smaller issue with orphaning is that it breaks the guarantee that packets will be delivered to device queues in-order. All TLS offload drivers depend on that scheduling property. This means skb_orphan_partial()'s trick of preserving partial socket references will cause issues in the drivers. We need a full orphan, and as a result netem delay/throttling will cause all TLS offload skbs to be dropped. Reusing the sk_buff->decrypted flag also protects from leaking clear text when incoming, decrypted skb is redirected (e.g. by TC). See commit 0608c69c9a80 ("bpf: sk_msg, sock{map|hash} redirect through ULP") for justification why the internal flag is safe. The only location which could leak the flag in is tcp_bpf_sendmsg(), which is taken care of by clearing the previously unused bit. v2: - remove superfluous decrypted mark copy (Willem); - remove the stale doc entry (Boris); - rely entirely on EOR marking to prevent coalescing (Boris); - use an internal sendpages flag instead of marking the socket (Boris). v3 (Willem): - reorganize the can_skb_orphan_partial() condition; - fix the flag leak-in through tcp_bpf_sendmsg. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Boris Pismenny <borisp@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b54c9d5b |
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30-Jul-2019 |
Jonathan Lemon <jonathan.lemon@gmail.com> |
net: Use skb_frag_off accessors Use accessor functions for skb fragment's page_offset instead of direct references, in preparation for bvec conversion. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d8e18a51 |
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22-Jul-2019 |
Matthew Wilcox (Oracle) <willy@infradead.org> |
net: Use skb accessors in network core In preparation for unifying the skb_frag and bio_vec, use the fine accessors which already exist and use skb_frag_t instead of struct skb_frag_struct. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8d650cde |
|
18-Jul-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: fix tcp_set_congestion_control() use from bpf hook Neal reported incorrect use of ns_capable() from bpf hook. bpf_setsockopt(...TCP_CONGESTION...) -> tcp_set_congestion_control() -> ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN) -> ns_capable_common() -> current_cred() -> rcu_dereference_protected(current->cred, 1) Accessing 'current' in bpf context makes no sense, since packets are processed from softirq context. As Neal stated : The capability check in tcp_set_congestion_control() was written assuming a system call context, and then was reused from a BPF call site. The fix is to add a new parameter to tcp_set_congestion_control(), so that the ns_capable() call is only performed under the right context. Fixes: 91b5b21c7c16 ("bpf: Add support for changing congestion control") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Lawrence Brakmo <brakmo@fb.com> Reported-by: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e858faf5 |
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06-Jul-2019 |
Christoph Paasch <cpaasch@apple.com> |
tcp: Reset bytes_acked and bytes_received when disconnecting If an app is playing tricks to reuse a socket via tcp_disconnect(), bytes_acked/received needs to be reset to 0. Otherwise tcp_info will report the sum of the current and the old connection.. Cc: Eric Dumazet <edumazet@google.com> Fixes: 0df48c26d841 ("tcp: add tcpi_bytes_acked to tcp_info") Fixes: bdd1f9edacb5 ("tcp: add tcpi_bytes_received to tcp_info") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
438ac880 |
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19-Jun-2019 |
Ard Biesheuvel <ardb@kernel.org> |
net: fastopen: robustness and endianness fixes for SipHash Some changes to the TCP fastopen code to make it more robust against future changes in the choice of key/cookie size, etc. - Instead of keeping the SipHash key in an untyped u8[] buffer and casting it to the right type upon use, use the correct type directly. This ensures that the key will appear at the correct alignment if we ever change the way these data structures are allocated. (Currently, they are only allocated via kmalloc so they always appear at the correct alignment) - Use DIV_ROUND_UP when sizing the u64[] array to hold the cookie, so it is always of sufficient size, even if TCP_FASTOPEN_COOKIE_MAX is no longer a multiple of 8. - Drop the 'len' parameter from the tcp_fastopen_reset_cipher() function, which is no longer used. - Add endian swabbing when setting the keys and calculating the hash, to ensure that cookie values are the same for a given key and source/destination address pair regardless of the endianness of the server. Note that none of these are functional changes wrt the current state of the code, with the exception of the swabbing, which only affects big endian systems. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2e05fcae |
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15-Jun-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: fix compile error if !CONFIG_SYSCTL tcp_tx_skb_cache_key and tcp_rx_skb_cache_key must be available even if CONFIG_SYSCTL is not set. Fixes: 0b7d7f6b2208 ("tcp: add tcp_tx_skb_cache sysctl") Fixes: ede61ca474a0 ("tcp: add tcp_rx_skb_cache sysctl") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3b4929f6 |
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17-May-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: limit payload size of sacked skbs Jonathan Looney reported that TCP can trigger the following crash in tcp_shifted_skb() : BUG_ON(tcp_skb_pcount(skb) < pcount); This can happen if the remote peer has advertized the smallest MSS that linux TCP accepts : 48 An skb can hold 17 fragments, and each fragment can hold 32KB on x86, or 64KB on PowerPC. This means that the 16bit witdh of TCP_SKB_CB(skb)->tcp_gso_segs can overflow. Note that tcp_sendmsg() builds skbs with less than 64KB of payload, so this problem needs SACK to be enabled. SACK blocks allow TCP to coalesce multiple skbs in the retransmit queue, thus filling the 17 fragments to maximal capacity. CVE-2019-11477 -- u16 overflow of TCP_SKB_CB(skb)->tcp_gso_segs Fixes: 832d11c5cd07 ("tcp: Try to restore large SKBs while SACK processing") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a842fe14 |
|
12-Jun-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: add optional per socket transmit delay Adding delays to TCP flows is crucial for studying behavior of TCP stacks, including congestion control modules. Linux offers netem module, but it has unpractical constraints : - Need root access to change qdisc - Hard to setup on egress if combined with non trivial qdisc like FQ - Single delay for all flows. EDT (Earliest Departure Time) adoption in TCP stack allows us to enable a per socket delay at a very small cost. Networking tools can now establish thousands of flows, each of them with a different delay, simulating real world conditions. This requires FQ packet scheduler or a EDT-enabled NIC. This patchs adds TCP_TX_DELAY socket option, to set a delay in usec units. unsigned int tx_delay = 10000; /* 10 msec */ setsockopt(fd, SOL_TCP, TCP_TX_DELAY, &tx_delay, sizeof(tx_delay)); Note that FQ packet scheduler limits might need some tweaking : man tc-fq PARAMETERS limit Hard limit on the real queue size. When this limit is reached, new packets are dropped. If the value is lowered, packets are dropped so that the new limit is met. Default is 10000 packets. flow_limit Hard limit on the maximum number of packets queued per flow. Default value is 100. Use of TCP_TX_DELAY option will increase number of skbs in FQ qdisc, so packets would be dropped if any of the previous limit is hit. Use of a jump label makes this support runtime-free, for hosts never using the option. Also note that TSQ (TCP Small Queues) limits are slightly changed with this patch : we need to account that skbs artificially delayed wont stop us providind more skbs to feed the pipe (netem uses skb_orphan_partial() for this purpose, but FQ can not use this trick) Because of that, using big delays might very well trigger old bugs in TSO auto defer logic and/or sndbuf limited detection. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0f1ce023 |
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28-May-2019 |
Jason Baron <jbaron@akamai.com> |
tcp: add support to TCP_FASTOPEN_KEY for optional backup key Add support for get/set of an optional backup key via TCP_FASTOPEN_KEY, in addition to the current 'primary' key. The primary key is used to encrypt and decrypt TFO cookies, while the backup is only used to decrypt TFO cookies. The backup key is used to maximize successful TFO connections when TFO keys are rotated. Currently, TCP_FASTOPEN_KEY allows a single 16-byte primary key to be set. This patch now allows a 32-byte value to be set, where the first 16 bytes are used as the primary key and the second 16 bytes are used for the backup key. Similarly, for getsockopt(), we can receive a 32-byte value as output if requested. If a 16-byte value is used to set the primary key via TCP_FASTOPEN_KEY, then any previously set backup key will be removed. Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9092a76d |
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28-May-2019 |
Jason Baron <jbaron@akamai.com> |
tcp: add backup TFO key infrastructure We would like to be able to rotate TFO keys while minimizing the number of client cookies that are rejected. Currently, we have only one key which can be used to generate and validate cookies, thus if we simply replace this key clients can easily have cookies rejected upon rotation. We propose having the ability to have both a primary key and a backup key. The primary key is used to generate as well as to validate cookies. The backup is only used to validate cookies. Thus, keys can be rotated as: 1) generate new key 2) add new key as the backup key 3) swap the primary and backup key, thus setting the new key as the primary We don't simply set the new key as the primary key and move the old key to the backup slot because the ip may be behind a load balancer and we further allow for the fact that all machines behind the load balancer will not be updated simultaneously. We make use of this infrastructure in subsequent patches. Suggested-by: Igor Lubashev <ilubashe@akamai.com> Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2874c5fd |
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27-May-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
858f5017 |
|
15-May-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: do not recycle cloned skbs It is illegal to change arbitrary fields in skb_shared_info if the skb is cloned. Before calling skb_zcopy_clear() we need to ensure this rule, therefore we need to move the test from sk_stream_alloc_skb() to sk_wmem_free_skb() Fixes: 4f661542a402 ("tcp: fix zerocopy and notsent_lowat issues") Signed-off-by: Eric Dumazet <edumazet@google.com> Diagnosed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
98fa6271 |
|
29-Apr-2019 |
Yuchung Cheng <ycheng@google.com> |
tcp: refactor setting the initial congestion window Relocate the congestion window initialization from tcp_init_metrics() to tcp_init_transfer() to improve code readability. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d7cc399e |
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19-Apr-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: properly reset skb->truesize for tx recycling tcp sendmsg() and sendpage() normally advance skb->data_len and skb->truesize by the payload added to an skb. But sendmsg(fd, ..., MSG_ZEROCOPY) has to account for whole pages, even if a single byte of payload is used in the page. This means that we can not assume skb->truesize can be adjusted by skb->data_len. We must instead overwrite its value. Otherwise skb->truesize is too big and can hit socket sndbuf limit, especially if the skb is recycled multiple times :/ Fixes: 472c2e07eef0 ("tcp: add one skb cache for tx") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
eb70a1ae |
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29-Mar-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: cleanup sk_tx_skb_cache before reuse TCP stack relies on the fact that a freshly allocated skb has skb->cb[] and skb_shinfo(skb)->tx_flags cleared. When recycling tx skb, we must ensure these fields are cleared. Fixes: 472c2e07eef0 ("tcp: add one skb cache for tx") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4f661542 |
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26-Mar-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: fix zerocopy and notsent_lowat issues My recent patch had at least three problems : 1) TX zerocopy wants notification when skb is acknowledged, thus we need to call skb_zcopy_clear() if the skb is cached into sk->sk_tx_skb_cache 2) Some applications might expect precise EPOLLOUT notifications, so we need to update sk->sk_wmem_queued and call sk_mem_uncharge() from sk_wmem_free_skb() in all cases. The SOCK_QUEUE_SHRUNK flag must also be set. 3) Reuse of saved skb should have used skb_cloned() instead of simply checking if the fast clone has been freed. Fixes: 472c2e07eef0 ("tcp: add one skb cache for tx") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8b27dae5 |
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22-Mar-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: add one skb cache for rx Often times, recvmsg() system calls and BH handling for a particular TCP socket are done on different cpus. This means the incoming skb had to be allocated on a cpu, but freed on another. This incurs a high spinlock contention in slab layer for small rpc, but also a high number of cache line ping pongs for larger packets. A full size GRO packet might use 45 page fragments, meaning that up to 45 put_page() can be involved. More over performing the __kfree_skb() in the recvmsg() context adds a latency for user applications, and increase probability of trapping them in backlog processing, since the BH handler might found the socket owned by the user. This patch, combined with the prior one increases the rpc performance by about 10 % on servers with large number of cores. (tcp_rr workload with 10,000 flows and 112 threads reach 9 Mpps instead of 8 Mpps) This also increases single bulk flow performance on 40Gbit+ links, since in this case there are often two cpus working in tandem : - CPU handling the NIC rx interrupts, feeding the receive queue, and (after this patch) freeing the skbs that were consumed. - CPU in recvmsg() system call, essentially 100 % busy copying out data to user space. Having at most one skb in a per-socket cache has very little risk of memory exhaustion, and since it is protected by socket lock, its management is essentially free. Note that if rps/rfs is used, we do not enable this feature, because there is high chance that the same cpu is handling both the recvmsg() system call and the TCP rx path, but that another cpu did the skb allocations in the device driver right before the RPS/RFS logic. To properly handle this case, it seems we would need to record on which cpu skb was allocated, and use a different channel to give skbs back to this cpu. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
472c2e07 |
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22-Mar-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: add one skb cache for tx On hosts with a lot of cores, RPC workloads suffer from heavy contention on slab spinlocks. 20.69% [kernel] [k] queued_spin_lock_slowpath 5.64% [kernel] [k] _raw_spin_lock 3.83% [kernel] [k] syscall_return_via_sysret 3.48% [kernel] [k] __entry_text_start 1.76% [kernel] [k] __netif_receive_skb_core 1.64% [kernel] [k] __fget For each sendmsg(), we allocate one skb, and free it at the time ACK packet comes. In many cases, ACK packets are handled by another cpus, and this unfortunately incurs heavy costs for slab layer. This patch uses an extra pointer in socket structure, so that we try to reuse the same skb and avoid these expensive costs. We cache at most one skb per socket so this should be safe as far as memory pressure is concerned. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6466e715 |
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06-Mar-2019 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: do not report TCP_CM_INQ of 0 for closed connections Returning 0 as inq to userspace indicates there is no more data to read, and the application needs to wait for EPOLLIN. For a connection that has received FIN from the remote peer, however, the application must continue reading until getting EOF (return value of 0 from tcp_recvmsg) or an error, if edge-triggered epoll (EPOLLET) is being used. Otherwise, the application will never receive a new EPOLLIN, since there is no epoll edge after the FIN. Return 1 when there is no data left on the queue but the connection has received FIN, so that the applications continue reading. Fixes: b75eba76d3d72 (tcp: send in-queue bytes in cmsg upon read) Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a10674bf |
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06-Mar-2019 |
Vasily Averin <vvs@virtuozzo.com> |
tcp: detecting the misuse of .sendpage for Slab objects sendpage was not designed for processing of the Slab pages, in some situations it can trigger BUG_ON on receiving side. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
921f9a0f |
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26-Feb-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: convert tcp_md5_needed to static_branch API We prefer static_branch_unlikely() over static_key_false() these days. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6c7b4ee7 |
|
26-Feb-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: get rid of tcp_check_send_head() This helper is used only once, and its name is no longer relevant. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
04c03114 |
|
15-Feb-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: clear icsk_backoff in tcp_write_queue_purge() soukjin bae reported a crash in tcp_v4_err() handling ICMP_DEST_UNREACH after tcp_write_queue_head(sk) returned a NULL pointer. Current logic should have prevented this : if (seq != tp->snd_una || !icsk->icsk_retransmits || !icsk->icsk_backoff || fastopen) break; Problem is the write queue might have been purged and icsk_backoff has not been cleared. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: soukjin bae <soukjin.bae@samsung.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9718475e |
|
02-Feb-2019 |
Deepa Dinamani <deepa.kernel@gmail.com> |
socket: Add SO_TIMESTAMPING_NEW Add SO_TIMESTAMPING_NEW variant of socket timestamp options. This is the y2038 safe versions of the SO_TIMESTAMPING_OLD for all architectures. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Cc: chris@zankel.net Cc: fenghua.yu@intel.com Cc: rth@twiddle.net Cc: tglx@linutronix.de Cc: ubraun@linux.ibm.com Cc: linux-alpha@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-s390@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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#
887feae3 |
|
02-Feb-2019 |
Deepa Dinamani <deepa.kernel@gmail.com> |
socket: Add SO_TIMESTAMP[NS]_NEW Add SO_TIMESTAMP_NEW and SO_TIMESTAMPNS_NEW variants of socket timestamp options. These are the y2038 safe versions of the SO_TIMESTAMP_OLD and SO_TIMESTAMPNS_OLD for all architectures. Note that the format of scm_timestamping.ts[0] is not changed in this patch. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Cc: jejb@parisc-linux.org Cc: ralf@linux-mips.org Cc: rth@twiddle.net Cc: linux-alpha@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-parisc@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: netdev@vger.kernel.org Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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#
13c6ee2a |
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02-Feb-2019 |
Deepa Dinamani <deepa.kernel@gmail.com> |
socket: Use old_timeval types for socket timestamps As part of y2038 solution, all internal uses of struct timeval are replaced by struct __kernel_old_timeval and struct compat_timeval by struct old_timeval32. Make socket timestamps use these new types. This is mainly to be able to verify that the kernel build is y2038 safe when such non y2038 safe types are not supported anymore. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Cc: isdn@linux-pingi.de Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7f1bc6e9 |
|
02-Feb-2019 |
Deepa Dinamani <deepa.kernel@gmail.com> |
sockopt: Rename SO_TIMESTAMP* to SO_TIMESTAMP*_OLD SO_TIMESTAMP, SO_TIMESTAMPNS and SO_TIMESTAMPING options, the way they are currently defined, are not y2038 safe. Subsequent patches in the series add new y2038 safe versions of these options which provide 64 bit timestamps on all architectures uniformly. Hence, rename existing options with OLD tag suffixes. Also note that kernel will not use the untagged SO_TIMESTAMP* and SCM_TIMESTAMP* options internally anymore. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Cc: deller@gmx.de Cc: dhowells@redhat.com Cc: jejb@parisc-linux.org Cc: ralf@linux-mips.org Cc: rth@twiddle.net Cc: linux-afs@lists.infradead.org Cc: linux-alpha@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-parisc@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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#
31954cd8 |
|
25-Jan-2019 |
Wei Wang <weiwan@google.com> |
tcp: Refactor pingpong code Instead of using pingpong as a single bit information, we refactor the code to treat it as a counter. When interactive session is detected, we set pingpong count to TCP_PINGPONG_THRESH. And when pingpong count is >= TCP_PINGPONG_THRESH, we consider the session in pingpong mode. This patch is a pure refactor and sets foundation for the next patch. This patch itself does not change any pingpong logic. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f859a448 |
|
25-Jan-2019 |
Willem de Bruijn <willemb@google.com> |
tcp: allow zerocopy with fastopen Accept MSG_ZEROCOPY in all the TCP states that allow sendmsg. Remove the explicit check for ESTABLISHED and CLOSE_WAIT states. This requires correctly handling zerocopy state (uarg, sk_zckey) in all paths reachable from other TCP states. Such as the EPIPE case in sk_stream_wait_connect, which a sendmsg() in incorrect state will now hit. Most paths are already safe. Only extension needed is for TCP Fastopen active open. This can build an skb with data in tcp_send_syn_data. Pass the uarg along with other fastopen state, so that this skb also generates a zerocopy notification on release. Tested with active and passive tcp fastopen packetdrill scripts at https://github.com/wdebruij/packetdrill/commit/1747eef03d25a2404e8132817d0f1244fd6f129d Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6bcdc40d |
|
17-Jan-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: move rx_opt & syn_data_acked init to tcp_disconnect() If we make sure all listeners have these fields cleared, then a clone will also inherit zero values. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
792c4354 |
|
17-Jan-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: move tp->rack init to tcp_disconnect() If we make sure all listeners have proper tp->rack value, then a clone will also inherit proper initial value. Note that fresh sockets init tp->rack from tcp_init_sock() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6cda8b74 |
|
17-Jan-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: move app_limited init to tcp_disconnect() If we make sure all listeners have app_limited set to ~0U, then a clone will also inherit proper initial value. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5c701549 |
|
17-Jan-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: move retrans_out, sacked_out, tlp_high_seq, last_oow_ack_time init to tcp_disconnect() If we make sure all listeners have these fields cleared, then a clone will also inherit zero values. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
3a9a57f6 |
|
17-Jan-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: move snd_cwnd & snd_cwnd_cnt init to tcp_disconnect() Passive connections can inherit proper value by cloning, if we make sure all listeners have the proper values there. tcp_disconnect() was setting snd_cwnd to 2, which seems quite obsolete since IW10 adoption. Also remove an obsolete comment. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b9e2e689 |
|
17-Jan-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: move mdev_us init to tcp_disconnect() If we make sure a listener always has its mdev_us field set to TCP_TIMEOUT_INIT, we do not need to rewrite this field after a new clone is created. tcp_disconnect() is very seldom used in real applications. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
6a408147 |
|
17-Jan-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: move icsk_rto init to tcp_disconnect() If we make sure a listener always has its icsk_rto field set to TCP_TIMEOUT_INIT, we do not need to rewrite this field after a new clone is created. tcp_disconnect() is very seldom used in real applications. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
13d7f463 |
|
10-Jan-2019 |
Willem de Bruijn <willemb@google.com> |
tcp: allow MSG_ZEROCOPY transmission also in CLOSE_WAIT state TCP transmission with MSG_ZEROCOPY fails if the peer closes its end of the connection and so transitions this socket to CLOSE_WAIT state. Transmission in close wait state is acceptable. Other similar tests in the stack (e.g., in FastOpen) accept both states. Relax this test, too. Link: https://www.mail-archive.com/netdev@vger.kernel.org/msg276886.html Link: https://www.mail-archive.com/netdev@vger.kernel.org/msg227390.html Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Reported-by: Marek Majkowski <marek@cloudflare.com> Signed-off-by: Willem de Bruijn <willemb@google.com> CC: Yuchung Cheng <ycheng@google.com> CC: Neal Cardwell <ncardwell@google.com> CC: Soheil Hassas Yeganeh <soheil@google.com> CC: Alexey Kodanev <alexey.kodanev@oracle.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fdb8b298 |
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06-Dec-2018 |
Pedro Tammela <pctammela@gmail.com> |
tcp: fix code style in tcp_recvmsg() 2 goto labels are indented with a tab. remove the tabs and keep the code style consistent. Signed-off-by: Pedro Tammela <pctammela@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
52900d22 |
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30-Nov-2018 |
Willem de Bruijn <willemb@google.com> |
udp: elide zerocopy operation in hot path With MSG_ZEROCOPY, each skb holds a reference to a struct ubuf_info. Release of its last reference triggers a completion notification. The TCP stack in tcp_sendmsg_locked holds an extra ref independent of the skbs, because it can build, send and free skbs within its loop, possibly reaching refcount zero and freeing the ubuf_info too soon. The UDP stack currently also takes this extra ref, but does not need it as all skbs are sent after return from __ip(6)_append_data. Avoid the extra refcount_inc and refcount_dec_and_test, and generally the sock_zerocopy_put in the common path, by passing the initial reference to the first skb. This approach is taken instead of initializing the refcount to 0, as that would generate error "refcount_t: increment on 0" on the next skb_zcopy_set. Changes v3 -> v4 - Move skb_zcopy_set below the only kfree_skb that might cause a premature uarg destroy before skb_zerocopy_put_abort - Move the entire skb_shinfo assignment block, to keep that cacheline access in one place Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6015c71e |
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27-Nov-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: add tcp_md5_needed jump label Most linux hosts never setup TCP MD5 keys. We can avoid a cache line miss (accessing tp->md5ig_info) on RX and TX using a jump label. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e8bd8fca |
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15-Nov-2018 |
Yousuk Seung <ysseung@google.com> |
tcp: add SRTT to SCM_TIMESTAMPING_OPT_STATS Add TCP_NLA_SRTT to SCM_TIMESTAMPING_OPT_STATS that reports the smoothed round trip time in microseconds (tcp_sock.srtt_us >> 3). Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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213d7767 |
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14-Nov-2018 |
Yafang Shao <laoar.shao@gmail.com> |
tcp: clean up STATE_TRACE Currently we can use bpf or tcp tracepoint to conveniently trace the tcp state transition at the run time. So we don't need to do this stuff at the compile time anymore. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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57c8a661 |
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30-Oct-2018 |
Mike Rapoport <rppt@linux.vnet.ibm.com> |
mm: remove include/linux/bootmem.h Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include <linux/memblock.h> @@ @@ - #include <linux/bootmem.h> + #include <linux/memblock.h> [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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89ab066d |
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23-Oct-2018 |
Karsten Graul <kgraul@linux.ibm.com> |
Revert "net: simplify sock_poll_wait" This reverts commit dd979b4df817e9976f18fb6f9d134d6bc4a3c317. This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an internal TCP socket for the initial handshake with the remote peer. Whenever the SMC connection can not be established this TCP socket is used as a fallback. All socket operations on the SMC socket are then forwarded to the TCP socket. In case of poll, the file->private_data pointer references the SMC socket because the TCP socket has no file assigned. This causes tcp_poll to wait on the wrong socket. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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76a9ebe8 |
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15-Oct-2018 |
Eric Dumazet <edumazet@google.com> |
net: extend sk_pacing_rate to unsigned long sk_pacing_rate has beed introduced as a u32 field in 2013, effectively limiting per flow pacing to 34Gbit. We believe it is time to allow TCP to pace high speed flows on 64bit hosts, as we now can reach 100Gbit on one TCP flow. This patch adds no cost for 32bit kernels. The tcpi_pacing_rate and tcpi_max_pacing_rate were already exported as 64bit, so iproute2/ss command require no changes. Unfortunately the SO_MAX_PACING_RATE socket option will stay 32bit and we will need to add a new option to let applications control high pacing rates. State Recv-Q Send-Q Local Address:Port Peer Address:Port ESTAB 0 1787144 10.246.9.76:49992 10.246.9.77:36741 timer:(on,003ms,0) ino:91863 sk:2 <-> skmem:(r0,rb540000,t66440,tb2363904,f605944,w1822984,o0,bl0,d0) ts sack bbr wscale:8,8 rto:201 rtt:0.057/0.006 mss:1448 rcvmss:536 advmss:1448 cwnd:138 ssthresh:178 bytes_acked:256699822585 segs_out:177279177 segs_in:3916318 data_segs_out:177279175 bbr:(bw:31276.8Mbps,mrtt:0,pacing_gain:1.25,cwnd_gain:2) send 28045.5Mbps lastrcv:73333 pacing_rate 38705.0Mbps delivery_rate 22997.6Mbps busy:73333ms unacked:135 retrans:0/157 rcv_space:14480 notsent:2085120 minrtt:0.013 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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8873c064 |
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02-Oct-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: do not release socket ownership in tcp_close() syzkaller was able to hit the WARN_ON(sock_owned_by_user(sk)); in tcp_close() While a socket is being closed, it is very possible other threads find it in rtnetlink dump. tcp_get_info() will acquire the socket lock for a short amount of time (slow = lock_sock_fast(sk)/unlock_sock_fast(sk, slow);), enough to trigger the warning. Fixes: 67db3e4bfbc9 ("tcp: no longer hold ehash lock while calling tcp_get_info()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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789762ce |
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26-Sep-2018 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: adjust rcv zerocopy hints based on frag sizes When SKBs are coalesced, we can have SKBs with different frag sizes. Some with PAGE_SIZE and some not with PAGE_SIZE. Since recv_skip_hint is always set to the full SKB size, it can overestimate the amount that should be read using normal read for coalesced packets. Change the recv_skip_hint so that it only includes the first frags that are not of PAGE_SIZE. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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8f2b0293 |
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26-Sep-2018 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: set recv_skip_hint when tcp_inq is less than PAGE_SIZE When we have less than PAGE_SIZE of data on receive queue, we set recv_skip_hint to 0. Instead, set it to the actual number of bytes available. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a337531b |
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27-Sep-2018 |
Yuchung Cheng <ycheng@google.com> |
tcp: up initial rmem to 128KB and SYN rwin to around 64KB Previously TCP initial receive buffer is ~87KB by default and the initial receive window is ~29KB (20 MSS). This patch changes the two numbers to 128KB and ~64KB (rounding down to the multiples of MSS) respectively. The patch also simplifies the calculations s.t. the two numbers are directly controlled by sysctl tcp_rmem[1]: 1) Initial receiver buffer budget (sk_rcvbuf): while this should be configured via sysctl tcp_rmem[1], previously tcp_fixup_rcvbuf() always override and set a larger size when a new connection establishes. 2) Initial receive window in SYN: previously it is set to 20 packets if MSS <= 1460. The number 20 was based on the initial congestion window of 10: the receiver needs twice amount to avoid being limited by the receive window upon out-of-order delivery in the first window burst. But since this only applies if the receiving MSS <= 1460, connection using large MTU (e.g. to utilize receiver zero-copy) may be limited by the receive window. With this patch TCP memory configuration is more straight-forward and more properly sized to modern high-speed networks by default. Several popular stacks have been announcing 64KB rwin in SYNs as well. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d3edd06e |
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21-Sep-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: provide earliest departure time in skb->tstamp Switch internal TCP skb->skb_mstamp to skb->skb_mstamp_ns, from usec units to nsec units. Do not clear skb->tstamp before entering IP stacks in TX, so that qdisc or devices can implement pacing based on the earliest departure time instead of socket sk->sk_pacing_rate Packets are fed with tcp_wstamp_ns, and following patch will update tcp_wstamp_ns when both TCP and sch_fq switch to the earliest departure time mechanism. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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5cf4a853 |
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06-Sep-2018 |
Vincent Whitchurch <vincent.whitchurch@axis.com> |
tcp: really ignore MSG_ZEROCOPY if no SO_ZEROCOPY According to the documentation in msg_zerocopy.rst, the SO_ZEROCOPY flag was introduced because send(2) ignores unknown message flags and any legacy application which was accidentally passing the equivalent of MSG_ZEROCOPY earlier should not see any new behaviour. Before commit f214f915e7db ("tcp: enable MSG_ZEROCOPY"), a send(2) call which passed the equivalent of MSG_ZEROCOPY without setting SO_ZEROCOPY would succeed. However, after that commit, it fails with -ENOBUFS. So it appears that the SO_ZEROCOPY flag fails to fulfill its intended purpose. Fix it. Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7788174e |
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29-Aug-2018 |
Yuchung Cheng <ycheng@google.com> |
tcp: change IPv6 flow-label upon receiving spurious retransmission Currently a Linux IPv6 TCP sender will change the flow label upon timeouts to potentially steer away from a data path that has gone bad. However this does not help if the problem is on the ACK path and the data path is healthy. In this case the receiver is likely to receive repeated spurious retransmission because the sender couldn't get the ACKs in time and has recurring timeouts. This patch adds another feature to mitigate this problem. It leverages the DSACK states in the receiver to change the flow label of the ACKs to speculatively re-route the ACK packets. In order to allow triggering on the second consecutive spurious RTO, the receiver changes the flow label upon sending a second consecutive DSACK for a sequence number below RCV.NXT. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a01512b1 |
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03-Aug-2018 |
YueHaibing <yuehaibing@huawei.com> |
tcp: remove unneeded variable 'err' variable 'err' is unmodified after initalization, so simply cleans up it and returns 0. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7ec65372 |
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31-Jul-2018 |
Wei Wang <weiwan@google.com> |
tcp: add stat of data packet reordering events Introduce a new TCP stats to record the number of reordering events seen and expose it in both tcp_info (TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS). Application can use this stats to track the frequency of the reordering events in addition to the existing reordering stats which tracks the magnitude of the latest reordering event. Note: this new stats tracks reordering events triggered by ACKs, which could often be fewer than the actual number of packets being delivered out-of-order. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7e10b655 |
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31-Jul-2018 |
Wei Wang <weiwan@google.com> |
tcp: add dsack blocks received stats Introduce a new TCP stat to record the number of DSACK blocks received (RFC4989 tcpEStatsStackDSACKDups) and expose it in both tcp_info (TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS). Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fb31c9b9 |
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31-Jul-2018 |
Wei Wang <weiwan@google.com> |
tcp: add data bytes retransmitted stats Introduce a new TCP stat to record the number of bytes retransmitted (RFC4898 tcpEStatsPerfOctetsRetrans) and expose it in both tcp_info (TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS). Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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ba113c3a |
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31-Jul-2018 |
Wei Wang <weiwan@google.com> |
tcp: add data bytes sent stats Introduce a new TCP stat to record the number of bytes sent (RFC4898 tcpEStatsPerfHCDataOctetsOut) and expose it in both tcp_info (TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS). Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
984988aa |
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31-Jul-2018 |
Wei Wang <weiwan@google.com> |
tcp: add a helper to calculate size of opt_stats This is to refactor the calculation of the size of opt_stats to a helper function to make the code cleaner and easier for later changes. Suggested-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
dd979b4d |
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30-Jul-2018 |
Christoph Hellwig <hch@lst.de> |
net: simplify sock_poll_wait The wait_address argument is always directly derived from the filp argument, so remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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9bcc66e1 |
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18-Jul-2018 |
Jon Maxwell <jmaxwell37@gmail.com> |
tcp: convert icsk_user_timeout from jiffies to msecs This is a preparatory commit. Part of this series that improves the socket TCP_USER_TIMEOUT option accuracy. Implement Eric Dumazets idea to convert icsk->icsk_user_timeout from jiffies to msecs. To eliminate the msecs_to_jiffies() and jiffies_to_msecs() dance in future. Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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e56b8ce3 |
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17-Jul-2018 |
Randy Dunlap <rdunlap@infradead.org> |
tcp: identify cryptic messages as TCP seq # bugs Attempt to make cryptic TCP seq number error messages clearer by (1) identifying the source of the message as "TCP", (2) identifying the errors as "seq # bug", and (3) grouping the field identifiers and values by separating them with commas. E.g., the following message is changed from: recvmsg bug 2: copied 73BCB6CD seq 70F17CBE rcvnxt 73BCB9AA fl 0 WARNING: CPU: 2 PID: 1501 at /linux/net/ipv4/tcp.c:1881 tcp_recvmsg+0x649/0xb90 to: TCP recvmsg seq # bug 2: copied 73BCB6CD, seq 70F17CBE, rcvnxt 73BCB9AA, fl 0 WARNING: CPU: 2 PID: 1501 at /linux/net/ipv4/tcp.c:2011 tcp_recvmsg+0x694/0xba0 Suggested-by: 積丹尼 Dan Jacobson <jidanni@jidanni.org> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
31048d7a |
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15-Jul-2018 |
Stefan Baranoff <sbaranoff@gmail.com> |
tcp: Fix broken repair socket window probe patch Correct previous bad attempt at allowing sockets to come out of TCP repair without sending window probes. To avoid changing size of the repair variable in struct tcp_sock, this lets the decision for sending probes or not to be made when coming out of repair by introducing two ways to turn it off. v2: * Remove erroneous comment; defines now make behavior clear Fixes: 70b7ff130224 ("tcp: allow user to create repair socket without window probes") Signed-off-by: Stefan Baranoff <sbaranoff@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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70b7ff13 |
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10-Jul-2018 |
Stefan Baranoff <sbaranoff@gmail.com> |
tcp: allow user to create repair socket without window probes Under rare conditions where repair code may be used it is possible that window probes are either unnecessary or undesired. If the user knows that window probes are not wanted or needed this change allows them to skip sending them when a socket comes out of repair. Signed-off-by: Stefan Baranoff <sbaranoff@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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95765a6c |
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09-Jul-2018 |
Julian Wiedmann <jwi@linux.ibm.com> |
tcp: remove SG-related comment in tcp_sendmsg() Since commit 74d4a8f8d378 ("tcp: remove sk_can_gso() use"), the code doesn't care whether the interface supports SG. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c47078d6 |
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08-Jul-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: remove redundant SOCK_DONE checks In both tcp_splice_read() and tcp_recvmsg(), we already test sock_flag(sk, SOCK_DONE) right before evaluating sk->sk_state, so "!sock_flag(sk, SOCK_DONE)" is always true. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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6508b678 |
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08-Jul-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: cleanup copied_seq and urg_data in tcp_disconnect tcp_zerocopy_receive() relies on tcp_inq() to limit number of bytes requested by user. syzbot found that after tcp_disconnect(), tcp_inq() was returning a stale value (number of bytes in queue before the disconnect). Note that after this patch, ioctl(fd, SIOCINQ, &val) is also fixed and returns 0, so this might be a candidate for all known linux kernels. While we are at this, we probably also should clear urg_data to avoid other syzkaller reports after it discovers how to deal with urgent data. syzkaller repro : socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 3 bind(3, {sa_family=AF_INET, sin_port=htons(20000), sin_addr=inet_addr("224.0.0.1")}, 16) = 0 connect(3, {sa_family=AF_INET, sin_port=htons(20000), sin_addr=inet_addr("127.0.0.1")}, 16) = 0 send(3, ..., 4096, 0) = 4096 connect(3, {sa_family=AF_UNSPEC, sa_data="\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 128) = 0 getsockopt(3, SOL_TCP, TCP_ZEROCOPY_RECEIVE, ..., [16]) = 0 // CRASH Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
acc2cf4e |
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07-Jul-2018 |
Lorenzo Colitti <lorenzo@google.com> |
net: diag: Don't double-free TCP_NEW_SYN_RECV sockets in tcp_abort When tcp_diag_destroy closes a TCP_NEW_SYN_RECV socket, it first frees it by calling inet_csk_reqsk_queue_drop_and_and_put in tcp_abort, and then frees it again by calling sock_gen_put. Since tcp_abort only has one caller, and all the other codepaths in tcp_abort don't free the socket, just remove the free in that function. Cc: David Ahern <dsa@cumulusnetworks.com> Tested: passes Android sock_diag_test.py, which exercises this codepath Fixes: d7226c7a4dd1 ("net: diag: Fix refcnt leak in error path destroying socket") Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsa@cumulusnetworks.com> Tested-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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657a0667 |
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06-Jul-2018 |
Willem de Bruijn <willemb@google.com> |
sock: sockc cookie initializer Initialize the cookie in one location to reduce code duplication and avoid bugs from inconsistent initialization, such as that fixed in commit 9887cba19978 ("ip: limit use of gso_size to udp"). Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a11e1d43 |
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28-Jun-2018 |
Linus Torvalds <torvalds@linux-foundation.org> |
Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL The poll() changes were not well thought out, and completely unexplained. They also caused a huge performance regression, because "->poll()" was no longer a trivial file operation that just called down to the underlying file operations, but instead did at least two indirect calls. Indirect calls are sadly slow now with the Spectre mitigation, but the performance problem could at least be largely mitigated by changing the "->get_poll_head()" operation to just have a per-file-descriptor pointer to the poll head instead. That gets rid of one of the new indirections. But that doesn't fix the new complexity that is completely unwarranted for the regular case. The (undocumented) reason for the poll() changes was some alleged AIO poll race fixing, but we don't make the common case slower and more complex for some uncommon special case, so this all really needs way more explanations and most likely a fundamental redesign. [ This revert is a revert of about 30 different commits, not reverted individually because that would just be unnecessarily messy - Linus ] Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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3f6c65d6 |
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19-Jun-2018 |
Wei Wang <weiwan@google.com> |
tcp: ignore rcv_rtt sample with old ts ecr value When receiving multiple packets with the same ts ecr value, only try to compute rcv_rtt sample with the earliest received packet. This is because the rcv_rtt calculated by later received packets could possibly include long idle time or other types of delay. For example: (1) server sends last packet of reply with TS val V1 (2) client ACKs last packet of reply with TS ecr V1 (3) long idle time passes (4) client sends next request data packet with TS ecr V1 (again!) At this time, the rcv_rtt computed on server with TS ecr V1 will be inflated with the idle time and should get ignored. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
867f816b |
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08-Jun-2018 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: limit sk_rcvlowat by the maximum receive buffer The user-provided value to setsockopt(SO_RCVLOWAT) can be larger than the maximum possible receive buffer. Such values mute POLLIN signals on the socket which can stall progress on the socket. Limit the user-provided value to half of the maximum receive buffer, i.e., half of sk_rcvbuf when the receive buffer size is set by the user, or otherwise half of sysctl_tcp_rmem[2]. Fixes: d1361840f8c5 ("tcp: fix SO_RCVLOWAT and RCVBUF autotuning") Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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2c7d3dac |
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09-Apr-2018 |
Christoph Hellwig <hch@lst.de> |
net/tcp: convert to ->poll_mask Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
5d9f4262 |
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17-May-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: add SACK compression When TCP receives an out-of-order packet, it immediately sends a SACK packet, generating network load but also forcing the receiver to send 1-MSS pathological packets, increasing its RTX queue length/depth, and thus processing time. Wifi networks suffer from this aggressive behavior, but generally speaking, all these SACK packets add fuel to the fire when networks are under congestion. This patch adds a high resolution timer and tp->compressed_ack counter. Instead of sending a SACK, we program this timer with a small delay, based on RTT and capped to 1 ms : delay = min ( 5 % of RTT, 1 ms) If subsequent SACKs need to be sent while the timer has not yet expired, we simply increment tp->compressed_ack. When timer expires, a SACK is sent with the latest information. Whenever an ACK is sent (if data is sent, or if in-order data is received) timer is canceled. Note that tcp_sack_new_ofo_skb() is able to force a SACK to be sent if the sack blocks need to be shuffled, even if the timer has not expired. A new SNMP counter is added in the following patch. Two other patches add sysctls to allow changing the 1,000,000 and 44 values that this commit hard-coded. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
114f39fe |
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02-May-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: restore autocorking When adding rb-tree for TCP retransmit queue, we inadvertently broke TCP autocorking. tcp_should_autocork() should really check if the rtx queue is not empty. Tested: Before the fix : $ nstat -n;./netperf -H 10.246.7.152 -Cc -- -m 500;nstat | grep AutoCork MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.246.7.152 () port 0 AF_INET Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 540000 262144 500 10.00 2682.85 2.47 1.59 3.618 2.329 TcpExtTCPAutoCorking 33 0.0 // Same test, but forcing TCP_NODELAY $ nstat -n;./netperf -H 10.246.7.152 -Cc -- -D -m 500;nstat | grep AutoCork MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.246.7.152 () port 0 AF_INET : nodelay Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 540000 262144 500 10.00 1408.75 2.44 2.96 6.802 8.259 TcpExtTCPAutoCorking 1 0.0 After the fix : $ nstat -n;./netperf -H 10.246.7.152 -Cc -- -m 500;nstat | grep AutoCork MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.246.7.152 () port 0 AF_INET Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 540000 262144 500 10.00 5472.46 2.45 1.43 1.761 1.027 TcpExtTCPAutoCorking 361293 0.0 // With TCP_NODELAY option $ nstat -n;./netperf -H 10.246.7.152 -Cc -- -D -m 500;nstat | grep AutoCork MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.246.7.152 () port 0 AF_INET : nodelay Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 540000 262144 500 10.00 5454.96 2.46 1.63 1.775 1.174 TcpExtTCPAutoCorking 315448 0.0 Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Michael Wenig <mwenig@vmware.com> Tested-by: Michael Wenig <mwenig@vmware.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Michael Wenig <mwenig@vmware.com> Tested-by: Michael Wenig <mwenig@vmware.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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b75eba76 |
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01-May-2018 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: send in-queue bytes in cmsg upon read Applications with many concurrent connections, high variance in receive queue length and tight memory bounds cannot allocate worst-case buffer size to drain sockets. Knowing the size of receive queue length, applications can optimize how they allocate buffers to read from the socket. The number of bytes pending on the socket is directly available through ioctl(FIONREAD/SIOCINQ) and can be approximated using getsockopt(MEMINFO) (rmem_alloc includes skb overheads in addition to application data). But, both of these options add an extra syscall per recvmsg. Moreover, ioctl(FIONREAD/SIOCINQ) takes the socket lock. Add the TCP_INQ socket option to TCP. When this socket option is set, recvmsg() relays the number of bytes available on the socket for reading to the application via the TCP_CM_INQ control message. Calculate the number of bytes after releasing the socket lock to include the processed backlog, if any. To avoid an extra branch in the hot path of recvmsg() for this new control message, move all cmsg processing inside an existing branch for processing receive timestamps. Since the socket lock is not held when calculating the size of receive queue, TCP_INQ is a hint. For example, it can overestimate the queue size by one byte, if FIN is received. With this method, applications can start reading from the socket using a small buffer, and then use larger buffers based on the remaining data when needed. V3 change-log: As suggested by David Miller, added loads with barrier to check whether we have multiple threads calling recvmsg in parallel. When that happens we lock the socket to calculate inq. V4 change-log: Removed inline from a static function. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Suggested-by: David Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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bf2acc94 |
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29-Apr-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: fix TCP_REPAIR_QUEUE bound checking syzbot is able to produce a nasty WARN_ON() in tcp_verify_left_out() with following C-repro : socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 3 setsockopt(3, SOL_TCP, TCP_REPAIR, [1], 4) = 0 setsockopt(3, SOL_TCP, TCP_REPAIR_QUEUE, [-1], 4) = 0 bind(3, {sa_family=AF_INET, sin_port=htons(20002), sin_addr=inet_addr("0.0.0.0")}, 16) = 0 sendto(3, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 1242, MSG_FASTOPEN, {sa_family=AF_INET, sin_port=htons(20002), sin_addr=inet_addr("127.0.0.1")}, 16) = 1242 setsockopt(3, SOL_TCP, TCP_REPAIR_WINDOW, "\4\0\0@+\205\0\0\377\377\0\0\377\377\377\177\0\0\0\0", 20) = 0 writev(3, [{"\270", 1}], 1) = 1 setsockopt(3, SOL_TCP, TCP_REPAIR_OPTIONS, "\10\0\0\0\0\0\0\0\0\0\0\0|\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 386) = 0 writev(3, [{"\210v\r[\226\320t\231qwQ\204\264l\254\t\1\20\245\214p\350H\223\254;\\\37\345\307p$"..., 3144}], 1) = 3144 The 3rd system call looks odd : setsockopt(3, SOL_TCP, TCP_REPAIR_QUEUE, [-1], 4) = 0 This patch makes sure bound checking is using an unsigned compare. Fixes: ee9952831cfd ("tcp: Initial repair mode") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
05255b82 |
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27-Apr-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive When adding tcp mmap() implementation, I forgot that socket lock had to be taken before current->mm->mmap_sem. syzbot eventually caught the bug. Since we can not lock the socket in tcp mmap() handler we have to split the operation in two phases. 1) mmap() on a tcp socket simply reserves VMA space, and nothing else. This operation does not involve any TCP locking. 2) getsockopt(fd, IPPROTO_TCP, TCP_ZEROCOPY_RECEIVE, ...) implements the transfert of pages from skbs to one VMA. This operation only uses down_read(¤t->mm->mmap_sem) after holding TCP lock, thus solving the lockdep issue. This new implementation was suggested by Andy Lutomirski with great details. Benefits are : - Better scalability, in case multiple threads reuse VMAS (without mmap()/munmap() calls) since mmap_sem wont be write locked. - Better error recovery. The previous mmap() model had to provide the expected size of the mapping. If for some reason one part could not be mapped (partial MSS), the whole operation had to be aborted. With the tcp_zerocopy_receive struct, kernel can report how many bytes were successfuly mapped, and how many bytes should be read to skip the problematic sequence. - No more memory allocation to hold an array of page pointers. 16 MB mappings needed 32 KB for this array, potentially using vmalloc() :/ - skbs are freed while mmap_sem has been released Following patch makes the change in tcp_mmap tool to demonstrate one possible use of mmap() and setsockopt(... TCP_ZEROCOPY_RECEIVE ...) Note that memcg might require additional changes. Fixes: 93ab6cc69162 ("tcp: implement mmap() for zero copy receive") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Suggested-by: Andy Lutomirski <luto@kernel.org> Cc: linux-mm@kvack.org Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
16ae6aa1 |
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25-Apr-2018 |
Yuchung Cheng <ycheng@google.com> |
tcp: ignore Fast Open on repair mode The TCP repair sequence of operation is to first set the socket in repair mode, then inject the TCP stats into the socket with repair socket options, then call connect() to re-activate the socket. The connect syscall simply returns and set state to ESTABLISHED mode. As a result Fast Open is meaningless for TCP repair. However allowing sendto() system call with MSG_FASTOPEN flag half-way during the repair operation could unexpectedly cause data to be sent, before the operation finishes changing the internal TCP stats (e.g. MSS). This in turn triggers TCP warnings on inconsistent packet accounting. The fix is to simply disallow Fast Open operation once the socket is in the repair mode. Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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feb5f2ec |
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18-Apr-2018 |
Yuchung Cheng <ycheng@google.com> |
tcp: export packets delivery info Export data delivered and delivered with CE marks to 1) SNMP TCPDelivered and TCPDeliveredCE 2) getsockopt(TCP_INFO) 3) Timestamping API SOF_TIMESTAMPING_OPT_STATS Note that for SCM_TSTAMP_ACK, the delivery info in SOF_TIMESTAMPING_OPT_STATS is reported before the info was fully updated on the ACK. These stats help application monitor TCP delivery and ECN status on per host, per connection, even per message level. Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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e21db6f6 |
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18-Apr-2018 |
Yuchung Cheng <ycheng@google.com> |
tcp: track total bytes delivered with ECN CE marks Introduce a new delivered_ce stat in tcp socket to estimate number of packets being marked with CE bits. The estimation is done via ACKs with ECE bit. Depending on the actual receiver behavior, the estimation could have biases. Since the TCP sender can't really see the CE bit in the data path, so the sender is technically counting packets marked delivered with the "ECE / ECN-Echo" flag set. With RFC3168 ECN, because the ECE bit is sticky, this count can drastically overestimate the nummber of CE-marked data packets With DCTCP-style ECN this should be reasonably precise unless there is loss in the ACK path, in which case it's not precise. With AccECN proposal this can be made still more precise, even in the case some degree of ACK loss. However this is sender's best estimate of CE information. Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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93ab6cc6 |
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16-Apr-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: implement mmap() for zero copy receive Some networks can make sure TCP payload can exactly fit 4KB pages, with well chosen MSS/MTU and architectures. Implement mmap() system call so that applications can avoid copying data without complex splice() games. Note that a successful mmap( X bytes) on TCP socket is consuming bytes, as if recvmsg() has been done. (tp->copied += X) Only PROT_READ mappings are accepted, as skb page frags are fundamentally shared and read only. If tcp_mmap() finds data that is not a full page, or a patch of urgent data, -EINVAL is returned, no bytes are consumed. Application must fallback to recvmsg() to read the problematic sequence. mmap() wont block, regardless of socket being in blocking or non-blocking mode. If not enough bytes are in receive queue, mmap() would return -EAGAIN, or -EIO if socket is in a state where no other bytes can be added into receive queue. An application might use SO_RCVLOWAT, poll() and/or ioctl( FIONREAD) to efficiently use mmap() On the sender side, MSG_EOR might help to clearly separate unaligned headers and 4K-aligned chunks if necessary. Tested: mlx4 (cx-3) 40Gbit NIC, with tcp_mmap program provided in following patch. MTU set to 4168 (4096 TCP payload, 40 bytes IPv6 header, 32 bytes TCP header) Without mmap() (tcp_mmap -s) received 32768 MB (0 % mmap'ed) in 8.13342 s, 33.7961 Gbit, cpu usage user:0.034 sys:3.778, 116.333 usec per MB, 63062 c-switches received 32768 MB (0 % mmap'ed) in 8.14501 s, 33.748 Gbit, cpu usage user:0.029 sys:3.997, 122.864 usec per MB, 61903 c-switches received 32768 MB (0 % mmap'ed) in 8.11723 s, 33.8635 Gbit, cpu usage user:0.048 sys:3.964, 122.437 usec per MB, 62983 c-switches received 32768 MB (0 % mmap'ed) in 8.39189 s, 32.7552 Gbit, cpu usage user:0.038 sys:4.181, 128.754 usec per MB, 55834 c-switches With mmap() on receiver (tcp_mmap -s -z) received 32768 MB (100 % mmap'ed) in 8.03083 s, 34.2278 Gbit, cpu usage user:0.024 sys:1.466, 45.4712 usec per MB, 65479 c-switches received 32768 MB (100 % mmap'ed) in 7.98805 s, 34.4111 Gbit, cpu usage user:0.026 sys:1.401, 43.5486 usec per MB, 65447 c-switches received 32768 MB (100 % mmap'ed) in 7.98377 s, 34.4296 Gbit, cpu usage user:0.028 sys:1.452, 45.166 usec per MB, 65496 c-switches received 32768 MB (99.9969 % mmap'ed) in 8.01838 s, 34.281 Gbit, cpu usage user:0.02 sys:1.446, 44.7388 usec per MB, 65505 c-switches Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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03f45c88 |
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16-Apr-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: avoid extra wakeups for SO_RCVLOWAT users SO_RCVLOWAT is properly handled in tcp_poll(), so that POLLIN is only generated when enough bytes are available in receive queue, after David change (commit c7004482e8dc "tcp: Respect SO_RCVLOWAT in tcp_poll().") But TCP still calls sk->sk_data_ready() for each chunk added in receive queue, meaning thread is awaken, and goes back to sleep shortly after. Tested: tcp_mmap test program, receiving 32768 MB of data with SO_RCVLOWAT set to 512KB -> Should get ~2 wakeups (c-switches) per MB, regardless of how many (tiny or big) packets were received. High speed (mostly full size GRO packets) received 32768 MB (100 % mmap'ed) in 8.03112 s, 34.2266 Gbit, cpu usage user:0.037 sys:1.404, 43.9758 usec per MB, 65497 c-switches received 32768 MB (99.9954 % mmap'ed) in 7.98453 s, 34.4263 Gbit, cpu usage user:0.03 sys:1.422, 44.3115 usec per MB, 65485 c-switches Low speed (sender is ratelimited and sends 1-MSS at a time, so GRO is not helping) received 22474.5 MB (100 % mmap'ed) in 6015.35 s, 0.0313414 Gbit, cpu usage user:0.05 sys:1.586, 72.7952 usec per MB, 44950 c-switches Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d1361840 |
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16-Apr-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: fix SO_RCVLOWAT and RCVBUF autotuning Applications might use SO_RCVLOWAT on TCP socket hoping to receive one [E]POLLIN event only when a given amount of bytes are ready in socket receive queue. Problem is that receive autotuning is not aware of this constraint, meaning sk_rcvbuf might be too small to allow all bytes to be stored. Add a new (struct proto_ops)->set_rcvlowat method so that a protocol can override the default setsockopt(SO_RCVLOWAT) behavior. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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bffd168c |
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14-Apr-2018 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: clear tp->packets_out when purging write queue Clear tp->packets_out when purging the write queue, otherwise tcp_rearm_rto() mistakenly assumes TCP write queue is not empty. This results in NULL pointer dereference. Also, remove the redundant `tp->packets_out = 0` from tcp_disconnect(), since tcp_disconnect() calls tcp_write_queue_purge(). Fixes: a27fd7a8ed38 (tcp: purge write queue upon RST) Reported-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Reported-by: Sami Farin <hvtaifwkbgefbaei@gmail.com> Tested-by: Sami Farin <hvtaifwkbgefbaei@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
72123032 |
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11-Apr-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets syzbot/KMSAN reported an uninit-value in tcp_parse_options() [1] I believe this was caused by a TCP_MD5SIG being set on live flow. This is highly unexpected, since TCP option space is limited. For instance, presence of TCP MD5 option automatically disables TCP TimeStamp option at SYN/SYNACK time, which we can not do once flow has been established. Really, adding/deleting an MD5 key only makes sense on sockets in CLOSE or LISTEN state. [1] BUG: KMSAN: uninit-value in tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720 CPU: 1 PID: 6177 Comm: syzkaller192004 Not tainted 4.16.0+ #83 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720 tcp_fast_parse_options net/ipv4/tcp_input.c:3858 [inline] tcp_validate_incoming+0x4f1/0x2790 net/ipv4/tcp_input.c:5184 tcp_rcv_established+0xf60/0x2bb0 net/ipv4/tcp_input.c:5453 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x2d6/0x680 net/core/sock.c:2271 release_sock+0x97/0x2a0 net/core/sock.c:2786 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747 SyS_sendto+0x8a/0xb0 net/socket.c:1715 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x448fe9 RSP: 002b:00007fd472c64d38 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000006e5a30 RCX: 0000000000448fe9 RDX: 000000000000029f RSI: 0000000020a88f88 RDI: 0000000000000004 RBP: 00000000006e5a34 R08: 0000000020e68000 R09: 0000000000000010 R10: 00000000200007fd R11: 0000000000000216 R12: 0000000000000000 R13: 00007fff074899ef R14: 00007fd472c659c0 R15: 0000000000000009 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slub.c:2737 [inline] __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:984 [inline] tcp_send_ack+0x18c/0x910 net/ipv4/tcp_output.c:3624 __tcp_ack_snd_check net/ipv4/tcp_input.c:5040 [inline] tcp_ack_snd_check net/ipv4/tcp_input.c:5053 [inline] tcp_rcv_established+0x2103/0x2bb0 net/ipv4/tcp_input.c:5469 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x2d6/0x680 net/core/sock.c:2271 release_sock+0x97/0x2a0 net/core/sock.c:2786 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747 SyS_sendto+0x8a/0xb0 net/socket.c:1715 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Fixes: cfb6eeb4c860 ("[TCP]: MD5 Signature Option (RFC2385) support.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8934ce2f |
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28-Mar-2018 |
John Fastabend <john.fastabend@gmail.com> |
bpf: sockmap redirect ingress support Add support for the BPF_F_INGRESS flag in sk_msg redirect helper. To do this add a scatterlist ring for receiving socks to check before calling into regular recvmsg call path. Additionally, because the poll wakeup logic only checked the skb recv queue we need to add a hook in TCP stack (similar to write side) so that we have a way to wake up polling socks when a scatterlist is redirected to that sock. After this all that is needed is for the redirect helper to push the scatterlist into the psock receive queue. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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#
312fc2b4 |
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18-Mar-2018 |
John Fastabend <john.fastabend@gmail.com> |
net: do_tcp_sendpages flag to avoid SKBTX_SHARED_FRAG When calling do_tcp_sendpages() from in kernel and we know the data has no references from user side we can omit SKBTX_SHARED_FRAG flag. This patch adds an internal flag, NO_SKBTX_SHARED_FRAG that can be used to omit setting SKBTX_SHARED_FRAG. The flag is not exposed to userspace because the sendpage call from the splice logic masks out all bits except MSG_MORE. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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#
7156d194 |
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16-Mar-2018 |
Yousuk Seung <ysseung@google.com> |
tcp: add snd_ssthresh stat in SCM_TIMESTAMPING_OPT_STATS This patch adds TCP_NLA_SND_SSTHRESH stat into SCM_TIMESTAMPING_OPT_STATS that reports tcp_sock.snd_ssthresh. Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e05836ac |
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06-Mar-2018 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: purge write queue upon aborting the connection When the connection is aborted, there is no point in keeping the packets on the write queue until the connection is closed. Similar to a27fd7a8ed38 ('tcp: purge write queue upon RST'), this is essential for a correct MSG_ZEROCOPY implementation, because userspace cannot call close(fd) before receiving zerocopy signals even when the connection is aborted. Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
be631892 |
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04-Mar-2018 |
Priyaranjan Jha <priyarjha@google.com> |
tcp: add ca_state stat in SCM_TIMESTAMPING_OPT_STATS This patch adds TCP_NLA_CA_STATE stat into SCM_TIMESTAMPING_OPT_STATS. It reports ca_state of socket, when timestamp is generated. Signed-off-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
87ecc95d |
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04-Mar-2018 |
Priyaranjan Jha <priyarjha@google.com> |
tcp: add send queue size stat in SCM_TIMESTAMPING_OPT_STATS This patch adds TCP_NLA_SENDQ_SIZE stat into SCM_TIMESTAMPING_OPT_STATS. It reports no. of bytes present in send queue, when timestamp is generated. Signed-off-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
65ec6097 |
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19-Feb-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: tcp_sendmsg() only deals with CHECKSUM_PARTIAL We no longer have skbs with skb->ip_summed == CHECKSUM_NONE in TCP write queues. We can remove dead code in tcp_sendmsg(). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
dead7cdb |
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19-Feb-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: remove sk_check_csum_caps() Since TCP relies on GSO, we do not need this helper anymore. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
74d4a8f8 |
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19-Feb-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: remove sk_can_gso() use After previous commit, sk_can_gso() is always true. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0a6b2a1d |
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19-Feb-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: switch to GSO being always on Oleksandr Natalenko reported performance issues with BBR without FQ packet scheduler that were root caused to lack of SG and GSO/TSO on his configuration. In this mode, TCP internal pacing has to setup a high resolution timer for each MSS sent. We could implement in TCP a strategy similar to the one adopted in commit fefa569a9d4b ("net_sched: sch_fq: account for schedule/timers drifts") or decide to finally switch TCP stack to a GSO only mode. This has many benefits : 1) Most TCP developments are done with TSO in mind. 2) Less high-resolution timers needs to be armed for TCP-pacing 3) GSO can benefit of xmit_more hint 4) Receiver GRO is more effective (as if TSO was used for real on sender) -> Lower ACK traffic 5) Write queues have less overhead (one skb holds about 64KB of payload) 6) SACK coalescing just works. 7) rtx rb-tree contains less packets, SACK is cheaper. This patch implements the minimum patch, but we can remove some legacy code as follow ups. Tested: On 40Gbit link, one netperf -t TCP_STREAM BBR+fq: sg on: 26 Gbits/sec sg off: 15.7 Gbits/sec (was 2.3 Gbit before patch) BBR+pfifo_fast: sg on: 24.2 Gbits/sec sg off: 14.9 Gbits/sec (was 0.66 Gbit before patch !!! ) BBR+fq_codel: sg on: 24.4 Gbits/sec sg off: 15 Gbits/sec (was 0.66 Gbit before patch !!! ) Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by: David S. Miller <davem@davemloft.net>
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a9a08845 |
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11-Feb-2018 |
Linus Torvalds <torvalds@linux-foundation.org> |
vfs: do bulk POLL* -> EPOLL* replacement This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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9b42d55a |
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26-Jan-2018 |
Li RongQing <lirongqing@baidu.com> |
tcp: release sk_frag.page in tcp_disconnect socket can be disconnected and gets transformed back to a listening socket, if sk_frag.page is not released, which will be cloned into a new socket by sk_clone_lock, but the reference count of this page is increased, lead to a use after free or double free issue Signed-off-by: Li RongQing <lirongqing@baidu.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d4487491 |
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25-Jan-2018 |
Lawrence Brakmo <brakmo@fb.com> |
bpf: Add BPF_SOCK_OPS_STATE_CB Adds support for calling sock_ops BPF program when there is a TCP state change. Two arguments are used; one for the old state and another for the new state. There is a new enum in include/uapi/linux/bpf.h that exports the TCP states that prepends BPF_ to the current TCP state names. If it is ever necessary to change the internal TCP state values (other than adding more to the end), then it will become necessary to convert from the internal TCP state value to the BPF value before calling the BPF sock_ops function. There are a set of compile checks added in tcp.c to detect if the internal and BPF values differ so we can make the necessary fixes. New op: BPF_SOCK_OPS_STATE_CB. Signed-off-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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#
de525be2 |
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25-Jan-2018 |
Lawrence Brakmo <brakmo@fb.com> |
bpf: Support passing args to sock_ops bpf function Adds support for passing up to 4 arguments to sock_ops bpf functions. It reusues the reply union, so the bpf_sock_ops structures are not increased in size. Signed-off-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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4ee806d5 |
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18-Jan-2018 |
Dan Streetman <ddstreet@ieee.org> |
net: tcp: close sock if net namespace is exiting When a tcp socket is closed, if it detects that its net namespace is exiting, close immediately and do not wait for FIN sequence. For normal sockets, a reference is taken to their net namespace, so it will never exit while the socket is open. However, kernel sockets do not take a reference to their net namespace, so it may begin exiting while the kernel socket is still open. In this case if the kernel socket is a tcp socket, it will stay open trying to complete its close sequence. The sock's dst(s) hold a reference to their interface, which are all transferred to the namespace's loopback interface when the real interfaces are taken down. When the namespace tries to take down its loopback interface, it hangs waiting for all references to the loopback interface to release, which results in messages like: unregister_netdevice: waiting for lo to become free. Usage count = 1 These messages continue until the socket finally times out and closes. Since the net namespace cleanup holds the net_mutex while calling its registered pernet callbacks, any new net namespace initialization is blocked until the current net namespace finishes exiting. After this change, the tcp socket notices the exiting net namespace, and closes immediately, releasing its dst(s) and their reference to the loopback interface, which lets the net namespace continue exiting. Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=97811 Signed-off-by: Dan Streetman <ddstreet@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
809a79e9 |
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10-Jan-2018 |
Wei Yongjun <weiyongjun1@huawei.com> |
tcp: make local function tcp_recv_timestamp static Fixes the following sparse warning: net/ipv4/tcp.c:1736:6: warning: symbol 'tcp_recv_timestamp' was not declared. Should it be static? Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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0a38806f |
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03-Jan-2018 |
Soheil Hassas Yeganeh <soheil@google.com> |
net: revert "Update RFS target at poll for tcp/udp" On multi-threaded processes, one common architecture is to have one (or a small number of) threads polling sockets, and a considerably larger pool of threads reading form and writing to the sockets. When we set RPS core on tcp_poll() or udp_poll() we essentially steer all packets of all the polled FDs to one (or small number of) cores, creaing a bottleneck and/or RPS misprediction. Another common architecture is to shard FDs among threads pinned to cores. In such a setting, setting RPS core in tcp_poll() and udp_poll() is redundant because the RFS core is correctly set in recvmsg and sendmsg. Thus, revert the following commit: c3f1dbaf6e28 ("net: Update RFS target at poll for tcp/udp"). Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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8ddab508 |
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22-Dec-2017 |
Willem de Bruijn <willemb@google.com> |
tcp: do not allocate linear memory for zerocopy skbs Zerocopy payload is now always stored in frags, and space for headers is reversed, so this memory is unused. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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02583ade |
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22-Dec-2017 |
Willem de Bruijn <willemb@google.com> |
tcp: place all zerocopy payload in frags This avoids an unnecessary copy of 1-2KB and improves tso_fragment, which has to fall back to tcp_fragment if skb->len != skb_data_len. It also avoids a surprising inconsistency in notifications: Zerocopy packets sent over loopback have their frags copied, so set SO_EE_CODE_ZEROCOPY_COPIED in the notification. But this currently does not happen for small packets, because when all data fits in the linear fragment, data is not copied in skb_orphan_frags_rx. Reported-by: Tom Deseyn <tom.deseyn@gmail.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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111856c7 |
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22-Dec-2017 |
Willem de Bruijn <willemb@google.com> |
tcp: push full zerocopy packets Skbs that reach MAX_SKB_FRAGS cannot be extended further. Do the same for zerocopy frags as non-zerocopy frags and set the PSH bit. This improves GRO assembly. Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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986ffdfd |
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19-Dec-2017 |
Yafang Shao <laoar.shao@gmail.com> |
net: sock: replace sk_state_load with inet_sk_state_load and remove sk_state_store sk_state_load is only used by AF_INET/AF_INET6, so rename it to inet_sk_state_load and move it into inet_sock.h. sk_state_store is removed as it is not used any more. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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563e0bb0 |
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19-Dec-2017 |
Yafang Shao <laoar.shao@gmail.com> |
net: tracepoint: replace tcp_set_state tracepoint with inet_sock_set_state tracepoint As sk_state is a common field for struct sock, so the state transition tracepoint should not be a TCP specific feature. Currently it traces all AF_INET state transition, so I rename this tracepoint to inet_sock_set_state tracepoint with some minor changes and move it into trace/events/sock.h. We dont need to create a file named trace/events/inet_sock.h for this one single tracepoint. Two helpers are introduced to trace sk_state transition - void inet_sk_state_store(struct sock *sk, int newstate); - void inet_sk_set_state(struct sock *sk, int state); As trace header should not be included in other header files, so they are defined in sock.c. The protocol such as SCTP maybe compiled as a ko, hence export inet_sk_set_state(). Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d4761754 |
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07-Dec-2017 |
Yousuk Seung <ysseung@google.com> |
tcp: invalidate rate samples during SACK reneging Mark tcp_sock during a SACK reneging event and invalidate rate samples while marked. Such rate samples may overestimate bw by including packets that were SACKed before reneging. < ack 6001 win 10000 sack 7001:38001 < ack 7001 win 0 sack 8001:38001 // Reneg detected > seq 7001:8001 // RTO, SACK cleared. < ack 38001 win 10000 In above example the rate sample taken after the last ack will count 7001-38001 as delivered while the actual delivery rate likely could be much lower i.e. 7001-8001. This patch adds a new field tcp_sock.sack_reneg and marks it when we declare SACK reneging and entering TCP_CA_Loss, and unmarks it after the last rate sample was taken before moving back to TCP_CA_Open. This patch also invalidates rate samples taken while tcp_sock.is_sack_reneg is set. Fixes: b9f64820fb22 ("tcp: track data delivery rate for a TCP connection") Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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27da6d37 |
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01-Dec-2017 |
Martin KaFai Lau <kafai@fb.com> |
tcp: Enable 2nd listener hashtable in TCP Enable the second listener hashtable in TCP. The scale is the same as UDP which is one slot per 2MB. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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ade994f4 |
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02-Jul-2017 |
Al Viro <viro@zeniv.linux.org.uk> |
net: annotate ->poll() instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
737ff314 |
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08-Nov-2017 |
Yuchung Cheng <ycheng@google.com> |
tcp: use sequence distance to detect reordering Replace the reordering distance measurement in packet unit with sequence based approach. Previously it trackes the number of "packets" toward the forward ACK (i.e. highest sacked sequence)in a state variable "fackets_out". Precisely measuring reordering degree on packet distance has not much benefit, as the degree constantly changes by factors like path, load, and congestion window. It is also complicated and prone to arcane bugs. This patch replaces with sequence-based approach that's much simpler. Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
713bafea |
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08-Nov-2017 |
Yuchung Cheng <ycheng@google.com> |
tcp: retire FACK loss detection FACK loss detection has been disabled by default and the successor RACK subsumed FACK and can handle reordering better. This patch removes FACK to simplify TCP loss recovery. Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
356d1833 |
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07-Nov-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_rmem and sysctl_tcp_wmem Note that when a new netns is created, it inherits its sysctl_tcp_rmem and sysctl_tcp_wmem from initial netns. This change is needed so that we can refine TCP rcvbuf autotuning, to take RTT into consideration. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1f255691 |
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03-Nov-2017 |
Priyaranjan Jha <priyarjha@google.com> |
tcp: higher throughput under reordering with adaptive RACK reordering wnd Currently TCP RACK loss detection does not work well if packets are being reordered beyond its static reordering window (min_rtt/4).Under such reordering it may falsely trigger loss recoveries and reduce TCP throughput significantly. This patch improves that by increasing and reducing the reordering window based on DSACK, which is now supported in major TCP implementations. It makes RACK's reo_wnd adaptive based on DSACK and no. of recoveries. - If DSACK is received, increment reo_wnd by min_rtt/4 (upper bounded by srtt), since there is possibility that spurious retransmission was due to reordering delay longer than reo_wnd. - Persist the current reo_wnd value for TCP_RACK_RECOVERY_THRESH (16) no. of successful recoveries (accounts for full DSACK-based loss recovery undo). After that, reset it to default (min_rtt/4). - At max, reo_wnd is incremented only once per rtt. So that the new DSACK on which we are reacting, is due to the spurious retx (approx) after the reo_wnd has been updated last time. - reo_wnd is tracked in terms of steps (of min_rtt/4), rather than absolute value to account for change in rtt. In our internal testing, we observed significant increase in throughput, in scenarios where reordering exceeds min_rtt/4 (previous static value). Signed-off-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
790f00e1 |
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27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_autocorking Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
26e9596e |
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27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_min_tso_segs Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0bc65a28 |
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26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_fack Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
60e2a778 |
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25-Oct-2017 |
Ursula Braun <ubraun@linux.vnet.ibm.com> |
tcp: TCP experimental option for SMC The SMC protocol [1] relies on the use of a new TCP experimental option [2, 3]. With this option, SMC capabilities are exchanged between peers during the TCP three way handshake. This patch adds support for this experimental option to TCP. References: [1] SMC-R Informational RFC: http://www.rfc-editor.org/info/rfc7609 [2] Shared Use of TCP Experimental Options RFC 6994: https://tools.ietf.org/rfc/rfc6994.txt [3] IANA ExID SMCR: http://www.iana.org/assignments/tcp-parameters/tcp-parameters.xhtml#tcp-exids Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
71c02379 |
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23-Oct-2017 |
Christoph Paasch <cpaasch@apple.com> |
tcp: Configure TFO without cookie per socket and/or per route We already allow to enable TFO without a cookie by using the fastopen-sysctl and setting it to TFO_SERVER_COOKIE_NOT_REQD (or TFO_CLIENT_NO_COOKIE). This is safe to do in certain environments where we know that there isn't a malicous host (aka., data-centers) or when the application-protocol already provides an authentication mechanism in the first flight of data. A server however might be providing multiple services or talking to both sides (public Internet and data-center). So, this server would want to enable cookie-less TFO for certain services and/or for connections that go to the data-center. This patch exposes a socket-option and a per-route attribute to enable such fine-grained configurations. Signed-off-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e8fce239 |
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23-Oct-2017 |
Song Liu <songliubraving@fb.com> |
tcp: add tracepoint trace_tcp_set_state() This patch adds tracepoint trace_tcp_set_state. Besides usual fields (s/d ports, IP addresses), old and new state of the socket is also printed with TP_printk, with __print_symbolic(). Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1fba70e5 |
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18-Oct-2017 |
Yuchung Cheng <ycheng@google.com> |
tcp: socket option to set TCP fast open key New socket option TCP_FASTOPEN_KEY to allow different keys per listener. The listener by default uses the global key until the socket option is set. The key is a 16 bytes long binary data. This option has no effect on regular non-listener TCP sockets. Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
75c119af |
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05-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: implement rb-tree based retransmit queue Using a linear list to store all skbs in write queue has been okay for quite a while : O(N) is not too bad when N < 500. Things get messy when N is the order of 100,000 : Modern TCP stacks want 10Gbit+ of throughput even with 200 ms RTT flows. 40 ns per cache line miss means a full scan can use 4 ms, blowing away CPU caches. SACK processing often can use various hints to avoid parsing whole retransmit queue. But with high packet losses and/or high reordering, hints no longer work. Sender has to process thousands of unfriendly SACK, accumulating a huge socket backlog, burning a cpu and massively dropping packets. Using an rb-tree for retransmit queue has been avoided for years because it added complexity and overhead, but now is the time to be more resistant and say no to quadratic behavior. 1) RTX queue is no longer part of the write queue : already sent skbs are stored in one rb-tree. 2) Since reaching the head of write queue no longer needs sk->sk_send_head, we added an union of sk_send_head and tcp_rtx_queue Tested: On receiver : netem on ingress : delay 150ms 200us loss 1 GRO disabled to force stress and SACK storms. for f in `seq 1 10` do ./netperf -H lpaa6 -l30 -- -K bbr -o THROUGHPUT|tail -1 done | awk '{print $0} {sum += $0} END {printf "%7u\n",sum}' Before patch : 323.87 351.48 339.59 338.62 306.72 204.07 304.93 291.88 202.47 176.88 2840 After patch: 1700.83 2207.98 2070.17 1544.26 2114.76 2124.89 1693.14 1080.91 2216.82 1299.94 18053 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4e8cc228 |
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05-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: tcp_tx_timestamp() cleanup tcp_write_queue_tail() call can be factorized. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ac3f09ba |
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05-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: uninline tcp_write_queue_purge() Since the upcoming rtx rbtree will add some extra code, it is time to not inline this fat function anymore. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e2080072 |
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04-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: new list for sent but unacked skbs for RACK recovery This patch adds a new queue (list) that tracks the sent but not yet acked or SACKed skbs for a TCP connection. The list is chronologically ordered by skb->skb_mstamp (the head is the oldest sent skb). This list will be used to optimize TCP Rack recovery, which checks an skb's timestamp to judge if it has been lost and needs to be retransmitted. Since TCP write queue is ordered by sequence instead of sent time, RACK has to scan over the write queue to catch all eligible packets to detect lost retransmission, and iterates through SACKed skbs repeatedly. Special cares for rare events: 1. TCP repair fakes skb transmission so the send queue needs adjusted 2. SACK reneging would require re-inserting SACKed skbs into the send queue. For now I believe it's not worth the complexity to make RACK work perfectly on SACK reneging, so we do nothing here. 3. Fast Open: currently for non-TFO, send-queue correctly queues the pure SYN packet. For TFO which queues a pure SYN and then a data packet, send-queue only queues the data packet but not the pure SYN due to the structure of TFO code. This is okay because the SYN receiver would never respond with a SACK on a missing SYN (i.e. SYN is never fast-retransmitted by SACK/RACK). In order to not grow sk_buff, we use an union for the new list and _skb_refdst/destructor fields. This is a bit complicated because we need to make sure _skb_refdst and destructor are properly zeroed before skb is cloned/copied at transmit, and before being freed. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
27204aaa |
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04-Oct-2017 |
Wei Wang <weiwan@google.com> |
tcp: uniform the set up of sockets after successful connection Currently in the TCP code, the initialization sequence for cached metrics, congestion control, BPF, etc, after successful connection is very inconsistent. This introduces inconsistent bevhavior and is prone to bugs. The current call sequence is as follows: (1) for active case (tcp_finish_connect() case): tcp_mtup_init(sk); icsk->icsk_af_ops->rebuild_header(sk); tcp_init_metrics(sk); tcp_call_bpf(sk, BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB); tcp_init_congestion_control(sk); tcp_init_buffer_space(sk); (2) for passive case (tcp_rcv_state_process() TCP_SYN_RECV case): icsk->icsk_af_ops->rebuild_header(sk); tcp_call_bpf(sk, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB); tcp_init_congestion_control(sk); tcp_mtup_init(sk); tcp_init_buffer_space(sk); tcp_init_metrics(sk); (3) for TFO passive case (tcp_fastopen_create_child()): inet_csk(child)->icsk_af_ops->rebuild_header(child); tcp_init_congestion_control(child); tcp_mtup_init(child); tcp_init_metrics(child); tcp_call_bpf(child, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB); tcp_init_buffer_space(child); This commit uniforms the above functions to have the following sequence: tcp_mtup_init(sk); icsk->icsk_af_ops->rebuild_header(sk); tcp_init_metrics(sk); tcp_call_bpf(sk, BPF_SOCK_OPS_ACTIVE/PASSIVE_ESTABLISHED_CB); tcp_init_congestion_control(sk); tcp_init_buffer_space(sk); This sequence is the same as the (1) active case. We pick this sequence because this order correctly allows BPF to override the settings including congestion control module and initial cwnd, etc from the route, and then allows the CC module to see those settings. Suggested-by: Neal Cardwell <ncardwell@google.com> Tested-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
43713848 |
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26-Sep-2017 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_fastopen_key knob Different namespace application might require different tcp_fastopen_key independently of the host. David Miller pointed out there is a leak without releasing the context of tcp_fastopen_key during netns teardown. So add the release action in exit_batch path. Tested: 1. Container namespace: # cat /proc/sys/net/ipv4/tcp_fastopen_key: 2817fff2-f803cf97-eadfd1f3-78c0992b cookie key in tcp syn packets: Fast Open Cookie Kind: TCP Fast Open Cookie (34) Length: 10 Fast Open Cookie: 1e5dd82a8c492ca9 2. Host: # cat /proc/sys/net/ipv4/tcp_fastopen_key: 107d7c5f-68eb2ac7-02fb06e6-ed341702 cookie key in tcp syn packets: Fast Open Cookie Kind: TCP Fast Open Cookie (34) Length: 10 Fast Open Cookie: e213c02bf0afbc8a Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
dd000598 |
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26-Sep-2017 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Remove the 'publish' logic in tcp_fastopen_init_key_once The 'publish' logic is not necessary after commit dfea2aa65424 ("tcp: Do not call tcp_fastopen_reset_cipher from interrupt context"), because in tcp_fastopen_cookie_gen,it wouldn't call tcp_fastopen_init_key_once. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e1cfcbe8 |
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26-Sep-2017 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_fastopen knob Different namespace application might require enable TCP Fast Open feature independently of the host. This patch series continues making more of the TCP Fast Open related sysctl knobs be per net-namespace. Reported-by: Luca BRUNO <lucab@debian.org> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
db5bce32 |
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31-Aug-2017 |
Eric Dumazet <edumazet@google.com> |
net: prepare (struct ubuf_info)->refcnt conversion In order to convert this atomic_t refcnt to refcount_t, we need to init the refcount to one to not trigger a 0 -> 1 transition. This also removes one atomic operation in fast path. v2: removed dead code in sock_zerocopy_put_abort() as suggested by Willem. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
31770e34 |
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30-Aug-2017 |
Florian Westphal <fw@strlen.de> |
tcp: Revert "tcp: remove header prediction" This reverts commit 45f119bf936b1f9f546a0b139c5b56f9bb2bdc78. Eric Dumazet says: We found at Google a significant regression caused by 45f119bf936b1f9f546a0b139c5b56f9bb2bdc78 tcp: remove header prediction In typical RPC (TCP_RR), when a TCP socket receives data, we now call tcp_ack() while we used to not call it. This touches enough cache lines to cause a slowdown. so problem does not seem to be HP removal itself but the tcp_ack() call. Therefore, it might be possible to remove HP after all, provided one finds a way to elide tcp_ack for most cases. Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bd9dfc54 |
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25-Aug-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: fix hang in tcp_sendpage_locked() syszkaller got a hang in tcp stack, related to a bug in tcp_sendpage_locked() root@syzkaller:~# cat /proc/3059/stack [<ffffffff83de926c>] __lock_sock+0x1dc/0x2f0 [<ffffffff83de9473>] lock_sock_nested+0xf3/0x110 [<ffffffff8408ce01>] tcp_sendmsg+0x21/0x50 [<ffffffff84163b6f>] inet_sendmsg+0x11f/0x5e0 [<ffffffff83dd8eea>] sock_sendmsg+0xca/0x110 [<ffffffff83dd9547>] kernel_sendmsg+0x47/0x60 [<ffffffff83de35dc>] sock_no_sendpage+0x1cc/0x280 [<ffffffff8408916b>] tcp_sendpage_locked+0x10b/0x160 [<ffffffff84089203>] tcp_sendpage+0x43/0x60 [<ffffffff841641da>] inet_sendpage+0x1aa/0x660 [<ffffffff83dd4fcd>] kernel_sendpage+0x8d/0xe0 [<ffffffff83dd50ac>] sock_sendpage+0x8c/0xc0 [<ffffffff81b63300>] pipe_to_sendpage+0x290/0x3b0 [<ffffffff81b67243>] __splice_from_pipe+0x343/0x750 [<ffffffff81b6a459>] splice_from_pipe+0x1e9/0x330 [<ffffffff81b6a5e0>] generic_splice_sendpage+0x40/0x50 [<ffffffff81b6b1d7>] SyS_splice+0x7b7/0x1610 [<ffffffff84d77a01>] entry_SYSCALL_64_fastpath+0x1f/0xbe Fixes: 306b13eb3cf9 ("proto_ops: Add locked held versions of sendmsg and sendpage") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Tom Herbert <tom@quantonium.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ebfa00c5 |
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25-Aug-2017 |
Sabrina Dubroca <sd@queasysnail.net> |
tcp: fix refcnt leak with ebpf congestion control There are a few bugs around refcnt handling in the new BPF congestion control setsockopt: - The new ca is assigned to icsk->icsk_ca_ops even in the case where we cannot get a reference on it. This would lead to a use after free, since that ca is going away soon. - Changing the congestion control case doesn't release the refcnt on the previous ca. - In the reinit case, we first leak a reference on the old ca, then we call tcp_reinit_congestion_control on the ca that we have just assigned, leading to deinitializing the wrong ca (->release of the new ca on the old ca's data) and releasing the refcount on the ca that we actually want to use. This is visible by building (for example) BIC as a module and setting net.ipv4.tcp_congestion_control=bic, and using tcp_cong_kern.c from samples/bpf. This patch fixes the refcount issues, and moves reinit back into tcp core to avoid passing a ca pointer back to BPF. Fixes: 91b5b21c7c16 ("bpf: Add support for changing congestion control") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
98aaa913 |
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22-Aug-2017 |
Mike Maloney <maloney@google.com> |
tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg When SOF_TIMESTAMPING_RX_SOFTWARE is enabled for tcp sockets, return the timestamp corresponding to the highest sequence number data returned. Previously the skb->tstamp is overwritten when a TCP packet is placed in the out of order queue. While the packet is in the ooo queue, save the timestamp in the TCB_SKB_CB. This space is shared with the gso_* options which are only used on the tx path, and a previously unused 4 byte hole. When skbs are coalesced either in the sk_receive_queue or the out_of_order_queue always choose the timestamp of the appended skb to maintain the invariant of returning the timestamp of the last byte in the recvmsg buffer. Signed-off-by: Mike Maloney <maloney@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
774c4673 |
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16-Aug-2017 |
David S. Miller <davem@davemloft.net> |
tcp: Export tcp_{sendpage,sendmsg}_locked() for ipv6. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f214f915 |
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03-Aug-2017 |
Willem de Bruijn <willemb@google.com> |
tcp: enable MSG_ZEROCOPY Enable support for MSG_ZEROCOPY to the TCP stack. TSO and GSO are both supported. Only data sent to remote destinations is sent without copying. Packets looped onto a local destination have their payload copied to avoid unbounded latency. Tested: A 10x TCP_STREAM between two hosts showed a reduction in netserver process cycles by up to 70%, depending on packet size. Systemwide, savings are of course much less pronounced, at up to 20% best case. msg_zerocopy.sh 4 tcp: without zerocopy tx=121792 (7600 MB) txc=0 zc=n rx=60458 (7600 MB) with zerocopy tx=286257 (17863 MB) txc=286257 zc=y rx=140022 (17863 MB) This test opens a pair of sockets over veth, one one calls send with 64KB and optionally MSG_ZEROCOPY and on the other reads the initial bytes. The receiver truncates, so this is strictly an upper bound on what is achievable. It is more representative of sending data out of a physical NIC (when payload is not touched, either). Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
306b13eb |
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28-Jul-2017 |
Tom Herbert <tom@quantonium.net> |
proto_ops: Add locked held versions of sendmsg and sendpage Add new proto_ops sendmsg_locked and sendpage_locked that can be called when the socket lock is already held. Correspondingly, add kernel_sendmsg_locked and kernel_sendpage_locked as front end functions. These functions will be used in zero proxy so that we can take the socket lock in a ULP sendmsg/sendpage and then directly call the backend transport proto_ops functions. Signed-off-by: Tom Herbert <tom@quantonium.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bb7c19f9 |
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28-Jul-2017 |
Wei Wang <weiwan@google.com> |
tcp: add related fields into SCM_TIMESTAMPING_OPT_STATS Add the following stats into SCM_TIMESTAMPING_OPT_STATS control msg: TCP_NLA_PACING_RATE TCP_NLA_DELIVERY_RATE TCP_NLA_SND_CWND TCP_NLA_REORDERING TCP_NLA_MIN_RTT TCP_NLA_RECUR_RETRANS TCP_NLA_DELIVERY_RATE_APP_LMT Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0263598c |
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28-Jul-2017 |
Wei Wang <weiwan@google.com> |
tcp: extract the function to compute delivery rate Refactor the code to extract the function to compute delivery rate. This function will be used in later commit. Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
45f119bf |
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29-Jul-2017 |
Florian Westphal <fw@strlen.de> |
tcp: remove header prediction Like prequeue, I am not sure this is overly useful nowadays. If we receive a train of packets, GRO will aggregate them if the headers are the same (HP predates GRO by several years) so we don't get a per-packet benefit, only a per-aggregated-packet one. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e7942d06 |
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29-Jul-2017 |
Florian Westphal <fw@strlen.de> |
tcp: remove prequeue support prequeue is a tcp receive optimization that moves part of rx processing from bh to process context. This only works if the socket being processed belongs to a process that is blocked in recv on that socket. In practice, this doesn't happen anymore that often because nowadays servers tend to use an event driven (epoll) model. Even normal client applications (web browsers) commonly use many tcp connections in parallel. This has measureable impact only in netperf (which uses plain recv and thus allows prequeue use) from host to locally running vm (~4%), however, there were no changes when using netperf between two physical hosts with ixgbe interfaces. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
91b5b21c |
|
30-Jun-2017 |
Lawrence Brakmo <brakmo@fb.com> |
bpf: Add support for changing congestion control Added support for changing congestion control for SOCK_OPS bpf programs through the setsockopt bpf helper function. It also adds a new SOCK_OPS op, BPF_SOCK_OPS_NEEDS_ECN, that is needed for congestion controls, like dctcp, that need to enable ECN in the SYN packets. Signed-off-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
14afee4b |
|
30-Jun-2017 |
Reshetova, Elena <elena.reshetova@intel.com> |
net: convert sock.sk_wmem_alloc from atomic_t to refcount_t refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d97af30f |
|
26-Jun-2017 |
Dave Watson <davejwatson@fb.com> |
tcp: fix null ptr deref in getsockopt(..., TCP_ULP, ...) If icsk_ulp_ops is unset, it dereferences a null ptr. Add a null ptr check. BUG: KASAN: null-ptr-deref in copy_to_user include/linux/uaccess.h:168 [inline] BUG: KASAN: null-ptr-deref in do_tcp_getsockopt.isra.33+0x24f/0x1e30 net/ipv4/tcp.c:3057 Read of size 4 at addr 0000000000000020 by task syz-executor1/15452 Signed-off-by: Dave Watson <davejwatson@fb.com> Reported-by: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d747a7a5 |
|
25-Jun-2017 |
WANG Cong <xiyou.wangcong@gmail.com> |
tcp: reset sk_rx_dst in tcp_disconnect() We have to reset the sk->sk_rx_dst when we disconnect a TCP connection, because otherwise when we re-connect it this dst reference is simply overridden in tcp_finish_connect(). This fixes a dst leak which leads to a loopback dev refcnt leak. It is a long-standing bug, Kevin reported a very similar (if not same) bug before. Thanks to Andrei for providing such a reliable reproducer which greatly narrows down the problem. Fixes: 41063e9dd119 ("ipv4: Early TCP socket demux.") Reported-by: Andrei Vagin <avagin@gmail.com> Reported-by: Kevin Xu <kaiwen.xu@hulu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8917a777 |
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15-Jun-2017 |
Ivan Delalande <colona@arista.com> |
tcp: md5: add TCP_MD5SIG_EXT socket option to set a key address prefix Replace first padding in the tcp_md5sig structure with a new flag field and address prefix length so it can be specified when configuring a new key for TCP MD5 signature. The tcpm_flags field will only be used if the socket option is TCP_MD5SIG_EXT to avoid breaking existing programs, and tcpm_prefixlen only when the TCP_MD5SIG_FLAG_PREFIX flag is set. Signed-off-by: Bob Gilligan <gilligan@arista.com> Signed-off-by: Eric Mowat <mowat@arista.com> Signed-off-by: Ivan Delalande <colona@arista.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e3b5616a |
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14-Jun-2017 |
Dave Watson <davejwatson@fb.com> |
tcp: export do_tcp_sendpages and tcp_rate_check_app_limited functions Export do_tcp_sendpages and tcp_rate_check_app_limited, since tls will need to sendpages while the socket is already locked. tcp_sendpage is exported, but requires the socket lock to not be held already. Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com> Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: Boris Pismenny <borisp@mellanox.com> Signed-off-by: Dave Watson <davejwatson@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
734942cc |
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14-Jun-2017 |
Dave Watson <davejwatson@fb.com> |
tcp: ULP infrastructure Add the infrustructure for attaching Upper Layer Protocols (ULPs) over TCP sockets. Based on a similar infrastructure in tcp_cong. The idea is that any ULP can add its own logic by changing the TCP proto_ops structure to its own methods. Example usage: setsockopt(sock, SOL_TCP, TCP_ULP, "tls", sizeof("tls")); modules will call: tcp_register_ulp(&tcp_tls_ulp_ops); to register/unregister their ulp, with an init function and name. A list of registered ulps will be returned by tcp_get_available_ulp, which is hooked up to /proc. Example: $ cat /proc/sys/net/ipv4/tcp_available_ulp tls There is currently no functionality to remove or chain ULPs, but it should be possible to add these in the future if needed. Signed-off-by: Boris Pismenny <borisp@mellanox.com> Signed-off-by: Dave Watson <davejwatson@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
06044751 |
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07-Jun-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: add TCPMemoryPressuresChrono counter DRAM supply shortage and poor memory pressure tracking in TCP stack makes any change in SO_SNDBUF/SO_RCVBUF (or equivalent autotuning limits) and tcp_mem[] quite hazardous. TCPMemoryPressures SNMP counter is an indication of tcp_mem sysctl limits being hit, but only tracking number of transitions. If TCP stack behavior under stress was perfect : 1) It would maintain memory usage close to the limit. 2) Memory pressure state would be entered for short times. We certainly prefer 100 events lasting 10ms compared to one event lasting 200 seconds. This patch adds a new SNMP counter tracking cumulative duration of memory pressure events, given in ms units. $ cat /proc/sys/net/ipv4/tcp_mem 3088 4117 6176 $ grep TCP /proc/net/sockstat TCP: inuse 180 orphan 0 tw 2 alloc 234 mem 4140 $ nstat -n ; sleep 10 ; nstat |grep Pressure TcpExtTCPMemoryPressures 1700 TcpExtTCPMemoryPressuresChrono 5209 v2: Used EXPORT_SYMBOL_GPL() instead of EXPORT_SYMBOL() as David instructed. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
15e56515 |
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26-May-2017 |
Douglas Caetano dos Santos <douglascs@taghos.com.br> |
tcp: reinitialize MTU probing when setting MSS in a TCP repair MTU probing initialization occurred only at connect() and at SYN or SYN-ACK reception, but the former sets MSS to either the default or the user set value (through TCP_MAXSEG sockopt) and the latter never happens with repaired sockets. The result was that, with MTU probing enabled and unless TCP_MAXSEG sockopt was used before connect(), probing would be stuck at tcp_base_mss value until tcp_probe_interval seconds have passed. Signed-off-by: Douglas Caetano dos Santos <douglascs@taghos.com.br> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ba615f67 |
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24-May-2017 |
Wei Wang <weiwan@google.com> |
tcp: avoid fastopen API to be used on AF_UNSPEC Fastopen API should be used to perform fastopen operations on the TCP socket. It does not make sense to use fastopen API to perform disconnect by calling it with AF_UNSPEC. The fastopen data path is also prone to race conditions and bugs when using with AF_UNSPEC. One issue reported and analyzed by Vegard Nossum is as follows: +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Thread A: Thread B: ------------------------------------------------------------------------ sendto() - tcp_sendmsg() - sk_stream_memory_free() = 0 - goto wait_for_sndbuf - sk_stream_wait_memory() - sk_wait_event() // sleep | sendto(flags=MSG_FASTOPEN, dest_addr=AF_UNSPEC) | - tcp_sendmsg() | - tcp_sendmsg_fastopen() | - __inet_stream_connect() | - tcp_disconnect() //because of AF_UNSPEC | - tcp_transmit_skb()// send RST | - return 0; // no reconnect! | - sk_stream_wait_connect() | - sock_error() | - xchg(&sk->sk_err, 0) | - return -ECONNRESET - ... // wake up, see sk->sk_err == 0 - skb_entail() on TCP_CLOSE socket If the connection is reopened then we will send a brand new SYN packet after thread A has already queued a buffer. At this point I think the socket internal state (sequence numbers etc.) becomes messed up. When the new connection is closed, the FIN-ACK is rejected because the sequence number is outside the window. The other side tries to retransmit, but __tcp_retransmit_skb() calls tcp_trim_head() on an empty skb which corrupts the skb data length and hits a BUG() in copy_and_csum_bits(). +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Hence, this patch adds a check for AF_UNSPEC in the fastopen data path and return EOPNOTSUPP to user if such case happens. Fixes: cf60af03ca4e7 ("tcp: Fast Open client - sendmsg(MSG_FASTOPEN)") Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a777f715 |
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22-May-2017 |
Rohit Chavan <roheetchavan@gmail.com> |
net: ipv4: tcp: fixed comment coding style issue Fixed a coding style issue Signed-off-by: Rohit Chavan <roheetchavan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
499350a5 |
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18-May-2017 |
Wei Wang <weiwan@google.com> |
tcp: initialize rcv_mss to TCP_MIN_MSS instead of 0 When tcp_disconnect() is called, inet_csk_delack_init() sets icsk->icsk_ack.rcv_mss to 0. This could potentially cause tcp_recvmsg() => tcp_cleanup_rbuf() => __tcp_select_window() call path to have division by 0 issue. So this patch initializes rcv_mss to TCP_MIN_MSS instead of 0. Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9a568de4 |
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16-May-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: switch TCP TS option (RFC 7323) to 1ms clock TCP Timestamps option is defined in RFC 7323 Traditionally on linux, it has been tied to the internal 'jiffies' variable, because it had been a cheap and good enough generator. For TCP flows on the Internet, 1 ms resolution would be much better than 4ms or 10ms (HZ=250 or HZ=100 respectively) For TCP flows in the DC, Google has used usec resolution for more than two years with great success [1] Receive size autotuning (DRS) is indeed more precise and converges faster to optimal window size. This patch converts tp->tcp_mstamp to a plain u64 value storing a 1 usec TCP clock. This choice will allow us to upstream the 1 usec TS option as discussed in IETF 97. [1] https://www.ietf.org/proceedings/97/slides/slides-97-tcpm-tcp-options-for-low-latency-00.pdf Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ac9517fc |
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16-May-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: replace misc tcp_time_stamp to tcp_jiffies32 After this patch, all uses of tcp_time_stamp will require a change when we introduce 1 ms and/or 1 us TCP TS option. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
628174cc |
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16-May-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: uses jiffies_32 to feed tp->chrono_start tcp_time_stamp will no longer be tied to jiffies. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d635fbe2 |
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16-May-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: use tcp_jiffies32 to feed tp->lsndtime Use tcp_jiffies32 instead of tcp_time_stamp to feed tp->lsndtime. tcp_time_stamp will soon be a litle bit more expensive than simply reading 'jiffies'. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d68be71e |
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26-Apr-2017 |
Davide Caratti <dcaratti@redhat.com> |
tcp: fix access to sk->sk_state in tcp_poll() avoid direct access to sk->sk_state when tcp_poll() is called on a socket using active TCP fastopen with deferred connect. Use local variable 'state', which stores the result of sk_state_load(), like it was done in commit 00fd38d938db ("tcp: ensure proper barriers in lockless contexts"). Fixes: 19f6d3f3c842 ("net/tcp-fastopen: Add new API support") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
645f4c6f |
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25-Apr-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: switch rcv_rtt_est and rcvq_space to high resolution timestamps Some devices or distributions use HZ=100 or HZ=250 TCP receive buffer autotuning has poor behavior caused by this choice. Since autotuning happens after 4 ms or 10 ms, short distance flows get their receive buffer tuned to a very high value, but after an initial period where it was frozen to (too small) initial value. With tp->tcp_mstamp introduction, we can switch to high resolution timestamps almost for free (at the expense of 8 additional bytes per TCP structure) Note that some TCP stacks use usec TCP timestamps where this patch makes even more sense : Many TCP flows have < 500 usec RTT. Hopefully this finer TS option can be standardized soon. Tested: HZ=100 kernel ./netperf -H lpaa24 -t TCP_RR -l 1000 -- -r 10000,10000 & Peer without patch : lpaa24:~# ss -tmi dst lpaa23 ... skmem:(r0,rb8388608,...) rcv_rtt:10 rcv_space:3210000 minrtt:0.017 Peer with the patch : lpaa23:~# ss -tmi dst lpaa24 ... skmem:(r0,rb428800,...) rcv_rtt:0.069 rcv_space:30000 minrtt:0.017 We can see saner RCVBUF, and more precise rcv_rtt information. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cf1ef3f0 |
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20-Apr-2017 |
Wei Wang <weiwan@google.com> |
net/tcp_fastopen: Disable active side TFO in certain scenarios Middlebox firewall issues can potentially cause server's data being blackholed after a successful 3WHS using TFO. Following are the related reports from Apple: https://www.nanog.org/sites/default/files/Paasch_Network_Support.pdf Slide 31 identifies an issue where the client ACK to the server's data sent during a TFO'd handshake is dropped. C ---> syn-data ---> S C <--- syn/ack ----- S C (accept & write) C <---- data ------- S C ----- ACK -> X S [retry and timeout] https://www.ietf.org/proceedings/94/slides/slides-94-tcpm-13.pdf Slide 5 shows a similar situation that the server's data gets dropped after 3WHS. C ---- syn-data ---> S C <--- syn/ack ----- S C ---- ack --------> S S (accept & write) C? X <- data ------ S [retry and timeout] This is the worst failure b/c the client can not detect such behavior to mitigate the situation (such as disabling TFO). Failing to proceed, the application (e.g., SSL library) may simply timeout and retry with TFO again, and the process repeats indefinitely. The proposed solution is to disable active TFO globally under the following circumstances: 1. client side TFO socket detects out of order FIN 2. client side TFO socket receives out of order RST We disable active side TFO globally for 1hr at first. Then if it happens again, we disable it for 2h, then 4h, 8h, ... And we reset the timeout to 1hr if a client side TFO sockets not opened on loopback has successfully received data segs from server. And we examine this condition during close(). The rational behind it is that when such firewall issue happens, application running on the client should eventually close the socket as it is not able to get the data it is expecting. Or application running on the server should close the socket as it is not able to receive any response from client. In both cases, out of order FIN or RST will get received on the client given that the firewall will not block them as no data are in those frames. And we want to disable active TFO globally as it helps if the middle box is very close to the client and most of the connections are likely to fail. Also, add a debug sysctl: tcp_fastopen_blackhole_detect_timeout_sec: the initial timeout to use when firewall blackhole issue happens. This can be set and read. When setting it to 0, it means to disable the active disable logic. Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
17c3060b |
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08-Apr-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: clear saved_syn in tcp_disconnect() In the (very unlikely) case a passive socket becomes a listener, we do not want to duplicate its saved SYN headers. This would lead to double frees, use after free, and please hackers and various fuzzers Tested: 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, IPPROTO_TCP, TCP_SAVE_SYN, [1], 4) = 0 +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 5) = 0 +0 < S 0:0(0) win 32972 <mss 1460,nop,wscale 7> +0 > S. 0:0(0) ack 1 <...> +.1 < . 1:1(0) ack 1 win 257 +0 accept(3, ..., ...) = 4 +0 connect(4, AF_UNSPEC, ...) = 0 +0 close(3) = 0 +0 bind(4, ..., ...) = 0 +0 listen(4, 5) = 0 +0 < S 0:0(0) win 32972 <mss 1460,nop,wscale 7> +0 > S. 0:0(0) ack 1 <...> +.1 < . 1:1(0) ack 1 win 257 Fixes: cd8ae85299d5 ("tcp: provide SYN headers for passive connections") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
589c49cb |
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04-Apr-2017 |
Gao Feng <fgao@ikuai8.com> |
net: tcp: Define the TCP_MAX_WSCALE instead of literal number 14 Define one new macro TCP_MAX_WSCALE instead of literal number '14', and use U16_MAX instead of 65535 as the max value of TCP window. There is another minor change, use rounddown(space, mss) instead of (space / mss) * mss; Signed-off-by: Gao Feng <fgao@ikuai8.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cfc62d87 |
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20-Mar-2017 |
Gao Feng <fgao@ikuai8.com> |
net: tcp: Permit user set TCP_MAXSEG to default value When user_mss is zero, it means use the default value. But the current codes don't permit user set TCP_MAXSEG to the default value. It would return the -EINVAL when val is zero. Signed-off-by: Gao Feng <fgao@ikuai8.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
db7f00b8 |
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16-Mar-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: tcp_get_info() should read tcp_time_stamp later Commit b369e7fd41f7 ("tcp: make TCP_INFO more consistent") moved lock_sock_fast() earlier in tcp_get_info() This has the minor effect that jiffies value being sampled at the beginning of tcp_get_info() is more likely to be off by one, and we report big tcpi_last_data_sent values (like 0xFFFFFFFF). Since we lock the socket, fetching tcp_time_stamp right before doing the jiffies_to_msecs() calls is enough to remove these wrong values. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7db92362 |
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01-Mar-2017 |
Wei Wang <weiwan@google.com> |
tcp: fix potential double free issue for fastopen_req tp->fastopen_req could potentially be double freed if a malicious user does the following: 1. Enable TCP_FASTOPEN_CONNECT sockopt and do a connect() on the socket. 2. Call connect() with AF_UNSPEC to disconnect the socket. 3. Make this socket a listening socket by calling listen(). 4. Accept incoming connections and generate child sockets. All child sockets will get a copy of the pointer of fastopen_req. 5. Call close() on all sockets. fastopen_req will get freed multiple times. Fixes: 19f6d3f3c842 ("net/tcp-fastopen: Add new API support") Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4e33e346 |
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17-Feb-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: use page_ref_inc() in tcp_sendmsg() sk_page_frag_refill() allocates either a compound page or an order-0 page. We can use page_ref_inc() which is slightly faster than get_page() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ccf7abb9 |
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03-Feb-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: avoid infinite loop in tcp_splice_read() Splicing from TCP socket is vulnerable when a packet with URG flag is received and stored into receive queue. __tcp_splice_read() returns 0, and sk_wait_data() immediately returns since there is the problematic skb in queue. This is a nice way to burn cpu (aka infinite loop) and trigger soft lockups. Again, this gem was found by syzkaller tool. Fixes: 9c55e01c0cc8 ("[TCP]: Splice receive support.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7e98102f |
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27-Jan-2017 |
Yuchung Cheng <ycheng@google.com> |
tcp: record pkts sent and retransmistted Add two stats in SCM_TIMESTAMPING_OPT_STATS: TCP_NLA_DATA_SEGS_OUT: total data packets sent including retransmission TCP_NLA_TOTAL_RETRANS: total data packets retransmitted The names are picked to be consistent with corresponding fields in TCP_INFO. This allows applications that are using the timestamping API to measure latency stats to also retrive retransmission rate of application write. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3979ad7e |
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25-Jan-2017 |
Willy Tarreau <w@1wt.eu> |
net/tcp-fastopen: make connect()'s return case more consistent with non-TFO Without TFO, any subsequent connect() call after a successful one returns -1 EISCONN. The last API update ensured that __inet_stream_connect() can return -1 EINPROGRESS in response to sendmsg() when TFO is in use to indicate that the connection is now in progress. Unfortunately since this function is used both for connect() and sendmsg(), it has the undesired side effect of making connect() now return -1 EINPROGRESS as well after a successful call, while at the same time poll() returns POLLOUT. This can confuse some applications which happen to call connect() and to check for -1 EISCONN to ensure the connection is usable, and for which EINPROGRESS indicates a need to poll, causing a loop. This problem was encountered in haproxy where a call to connect() is precisely used in certain cases to confirm a connection's readiness. While arguably haproxy's behaviour should be improved here, it seems important to aim at a more robust behaviour when the goal of the new API is to make it easier to implement TFO in existing applications. This patch simply ensures that we preserve the same semantics as in the non-TFO case on the connect() syscall when using TFO, while still returning -1 EINPROGRESS on sendmsg(). For this we simply tell __inet_stream_connect() whether we're doing a regular connect() or in fact connecting for a sendmsg() call. Cc: Wei Wang <weiwan@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
19f6d3f3 |
|
23-Jan-2017 |
Wei Wang <weiwan@google.com> |
net/tcp-fastopen: Add new API support This patch adds a new socket option, TCP_FASTOPEN_CONNECT, as an alternative way to perform Fast Open on the active side (client). Prior to this patch, a client needs to replace the connect() call with sendto(MSG_FASTOPEN). This can be cumbersome for applications who want to use Fast Open: these socket operations are often done in lower layer libraries used by many other applications. Changing these libraries and/or the socket call sequences are not trivial. A more convenient approach is to perform Fast Open by simply enabling a socket option when the socket is created w/o changing other socket calls sequence: s = socket() create a new socket setsockopt(s, IPPROTO_TCP, TCP_FASTOPEN_CONNECT …); newly introduced sockopt If set, new functionality described below will be used. Return ENOTSUPP if TFO is not supported or not enabled in the kernel. connect() With cookie present, return 0 immediately. With no cookie, initiate 3WHS with TFO cookie-request option and return -1 with errno = EINPROGRESS. write()/sendmsg() With cookie present, send out SYN with data and return the number of bytes buffered. With no cookie, and 3WHS not yet completed, return -1 with errno = EINPROGRESS. No MSG_FASTOPEN flag is needed. read() Return -1 with errno = EWOULDBLOCK/EAGAIN if connect() is called but write() is not called yet. Return -1 with errno = EWOULDBLOCK/EAGAIN if connection is established but no msg is received yet. Return number of bytes read if socket is established and there is msg received. The new API simplifies life for applications that always perform a write() immediately after a successful connect(). Such applications can now take advantage of Fast Open by merely making one new setsockopt() call at the time of creating the socket. Nothing else about the application's socket call sequence needs to change. Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c2a2efbb |
|
20-Jan-2017 |
Eric Dumazet <edumazet@google.com> |
net: remove bh disabling around percpu_counter accesses Shaohua Li made percpu_counter irq safe in commit 098faf5805c8 ("percpu_counter: make APIs irq safe") We can safely remove BH disable/enable sections around various percpu_counter manipulations. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4a7f6009 |
|
12-Jan-2017 |
Yuchung Cheng <ycheng@google.com> |
tcp: remove thin_dupack feature Thin stream DUPACK is to start fast recovery on only one DUPACK provided the connection is a thin stream (i.e., low inflight). But this older feature is now subsumed with RACK. If a connection receives only a single DUPACK, RACK would arm a reordering timer and soon starts fast recovery instead of timeout if no further ACKs are received. The socket option (THIN_DUPACK) is kept as a nop for compatibility. Note that this patch does not change another thin-stream feature which enables linear RTO. Although it might be good to generalize that in the future (i.e., linear RTO for the first say 3 retries). Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bec41a11 |
|
12-Jan-2017 |
Yuchung Cheng <ycheng@google.com> |
tcp: remove early retransmit This patch removes the support of RFC5827 early retransmit (i.e., fast recovery on small inflight with <3 dupacks) because it is subsumed by the new RACK loss detection. More specifically when RACK receives DUPACKs, it'll arm a reordering timer to start fast recovery after a quarter of (min)RTT, hence it covers the early retransmit except RACK does not limit itself to specific inflight or dupack numbers. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b369e7fd |
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09-Jan-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: make TCP_INFO more consistent tcp_get_info() has to lock the socket, so lets lock it for an extended critical section, so that various fields have consistent values. This solves an annoying issue that some applications reported when multiple counters are updated during one particular rx/rx event, and TCP_INFO was called from another cpu. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ad02c4f5 |
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04-Jan-2017 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: provide timestamps for partial writes For TCP sockets, TX timestamps are only captured when the user data is successfully and fully written to the socket. In many cases, however, TCP writes can be partial for which no timestamp is collected. Collect timestamps whenever any user data is (fully or partially) copied into the socket. Pass tcp_write_queue_tail to tcp_tx_timestamp instead of the local skb pointer since it can be set to NULL on the error path. Note that tcp_write_queue_tail can be NULL, even if bytes have been copied to the socket. This is because acknowledgements are being processed in tcp_sendmsg(), and by the time tcp_tx_timestamp is called tcp_write_queue_tail can be NULL. For such cases, this patch does not collect any timestamps (i.e., it is best-effort). This patch is written with suggestions from Willem de Bruijn and Eric Dumazet. Change-log V1 -> V2: - Use sockc.tsflags instead of sk->sk_tsflags. - Use the same code path for normal writes and errors. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Martin KaFai Lau <kafai@fb.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fee83d09 |
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28-Dec-2016 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_max_syn_backlog knob Different namespace application might require different maximal number of remembered connection requests. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1946e672 |
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28-Dec-2016 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_tw_recycle and tcp_max_tw_buckets knob Different namespace application might require fast recycling TIME-WAIT sockets independently of the host. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7c0f6ba6 |
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24-Dec-2016 |
Linus Torvalds <torvalds@linux-foundation.org> |
Replace <asm/uaccess.h> with <linux/uaccess.h> globally This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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7aa5470c |
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03-Dec-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: tsq: move tsq_flags close to sk_wmem_alloc tsq_flags being in the same cache line than sk_wmem_alloc makes a lot of sense. Both fields are changed from tcp_wfree() and more generally by various TSQ related functions. Prior patch made room in struct sock and added sk_tsq_flags, this patch deletes tsq_flags from struct tcp_sock. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1c885808 |
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28-Nov-2016 |
Francis Yan <francisyyan@gmail.com> |
tcp: SOF_TIMESTAMPING_OPT_STATS option for SO_TIMESTAMPING This patch exports the sender chronograph stats via the socket SO_TIMESTAMPING channel. Currently we can instrument how long a particular application unit of data was queued in TCP by tracking SOF_TIMESTAMPING_TX_SOFTWARE and SOF_TIMESTAMPING_TX_SCHED. Having these sender chronograph stats exported simultaneously along with these timestamps allow further breaking down the various sender limitation. For example, a video server can tell if a particular chunk of video on a connection takes a long time to deliver because TCP was experiencing small receive window. It is not possible to tell before this patch without packet traces. To prepare these stats, the user needs to set SOF_TIMESTAMPING_OPT_STATS and SOF_TIMESTAMPING_OPT_TSONLY flags while requesting other SOF_TIMESTAMPING TX timestamps. When the timestamps are available in the error queue, the stats are returned in a separate control message of type SCM_TIMESTAMPING_OPT_STATS, in a list of TLVs (struct nlattr) of types: TCP_NLA_BUSY_TIME, TCP_NLA_RWND_LIMITED, TCP_NLA_SNDBUF_LIMITED. Unit is microsecond. Signed-off-by: Francis Yan <francisyyan@gmail.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
efd90174 |
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28-Nov-2016 |
Francis Yan <francisyyan@gmail.com> |
tcp: export sender limits chronographs to TCP_INFO This patch exports all the sender chronograph measurements collected in the previous patches to TCP_INFO interface. Note that busy time exported includes all the other sending limits (rwnd-limited, sndbuf-limited). Internally the time unit is jiffy but externally the measurements are in microseconds for future extensions. Signed-off-by: Francis Yan <francisyyan@gmail.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b0f71bd3 |
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28-Nov-2016 |
Francis Yan <francisyyan@gmail.com> |
tcp: instrument how long TCP is limited by insufficient send buffer This patch measures the amount of time when TCP runs out of new data to send to the network due to insufficient send buffer, while TCP is still busy delivering (i.e. write queue is not empty). The goal is to indicate either the send buffer autotuning or user SO_SNDBUF setting has resulted network under-utilization. The measurement starts conservatively by checking various conditions to minimize false claims (i.e. under-estimation is more likely). The measurement stops when the SOCK_NOSPACE flag is cleared. But it does not account the time elapsed till the next application write. Also the measurement only starts if the sender is still busy sending data, s.t. the limit accounted is part of the total busy time. Signed-off-by: Francis Yan <francisyyan@gmail.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
319b0534 |
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14-Nov-2016 |
Andrey Vagin <avagin@openvz.org> |
tcp: allow to enable the repair mode for non-listening sockets The repair mode is used to get and restore sequence numbers and data from queues. It used to checkpoint/restore connections. Currently the repair mode can be enabled for sockets in the established and closed states, but for other states we have to dump the same socket properties, so lets allow to enable repair mode for these sockets. The repair mode reveals nothing more for sockets in other states. Signed-off-by: Andrei Vagin <avagin@openvz.org> Acked-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f522a5fc |
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09-Nov-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: remove unaligned accesses from tcp_get_info() After commit 6ed46d1247a5 ("sock_diag: align nlattr properly when needed"), tcp_get_info() gets 64bit aligned memory, so we can avoid the unaligned helpers. Suggested-by: David Miller <davem@davemloft.net> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
67db3e4b |
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04-Nov-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: no longer hold ehash lock while calling tcp_get_info() We had various problems in the past in tcp_get_info() and used specific synchronization to avoid deadlocks. We would like to add more instrumentation points for TCP, and avoiding grabing socket lock in tcp_getinfo() was too costly. Being able to lock the socket allows to provide consistent set of fields. inet_diag_dump_icsk() can make sure ehash locks are not held any more when tcp_get_info() is called. We can remove syncp added in commit d654976cbf85 ("tcp: fix a potential deadlock in tcp_get_info()"), but we need to use lock_sock_fast() instead of spin_lock_bh() since TCP input path can now be run from process context. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ccbf3bfa |
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04-Nov-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: shortcut listeners in tcp_get_info() Being lockless in tcp_get_info() is hard, because we need to add specific synchronization in TCP fast path, like seqcount. Following patch will change inet_diag_dump_icsk() to no longer hold any lock for non listeners, so that we can properly acquire socket lock in get_tcp_info() and let it return more consistent counters. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
79d8665b |
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02-Nov-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: fix return value for partial writes After my commit, tcp_sendmsg() might restart its loop after processing socket backlog. If sk_err is set, we blindly return an error, even though we copied data to user space before. We should instead return number of bytes that could be copied, otherwise user space might resend data and corrupt the stream. This might happen if another thread is using recvmsg(MSG_ERRQUEUE) to process timestamps. Issue was diagnosed by Soheil and Willem, big kudos to them ! Fixes: d41a69f1d390f ("tcp: make tcp_sendmsg() aware of socket backlog") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Tested-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ac9e70b1 |
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02-Nov-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: fix potential memory corruption Imagine initial value of max_skb_frags is 17, and last skb in write queue has 15 frags. Then max_skb_frags is lowered to 14 or smaller value. tcp_sendmsg() will then be allowed to add additional page frags and eventually go past MAX_SKB_FRAGS, overflowing struct skb_shared_info. Fixes: 5f74f82ea34c ("net:Add sysctl_max_skb_frags") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hans Westgaard Ry <hans.westgaard.ry@oracle.com> Cc: Håkon Bugge <haakon.bugge@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2d758073 |
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07-Oct-2016 |
Johannes Weiner <hannes@cmpxchg.org> |
mm: memcontrol: consolidate cgroup socket tracking The cgroup core and the memory controller need to track socket ownership for different purposes, but the tracking sites being entirely different is kind of ugly. Be a better citizen and rename the memory controller callbacks to match the cgroup core callbacks, then move them to the same place. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20160914194846.11153-3-hannes@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
25869262 |
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17-Sep-2016 |
Al Viro <viro@zeniv.linux.org.uk> |
skb_splice_bits(): get rid of callback since pipe_lock is the outermost now, we don't need to drop/regain socket locks around the call of splice_to_pipe() from skb_splice_bits(), which kills the need to have a socket-specific callback; we can just call splice_to_pipe() and be done with that. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
eb8329e0 |
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19-Sep-2016 |
Yuchung Cheng <ycheng@google.com> |
tcp: export data delivery rate This commit export two new fields in struct tcp_info: tcpi_delivery_rate: The most recent goodput, as measured by tcp_rate_gen(). If the socket is limited by the sending application (e.g., no data to send), it reports the highest measurement instead of the most recent. The unit is bytes per second (like other rate fields in tcp_info). tcpi_delivery_rate_app_limited: A boolean indicating if the goodput was measured when the socket's throughput was limited by the sending application. This delivery rate information can be useful for applications that want to know the current throughput the TCP connection is seeing, e.g. adaptive bitrate video streaming. It can also be very useful for debugging or troubleshooting. Signed-off-by: Van Jacobson <vanj@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Nandita Dukkipati <nanditad@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d7722e85 |
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19-Sep-2016 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: track application-limited rate samples This commit adds code to track whether the delivery rate represented by each rate_sample was limited by the application. Upon each transmit, we store in the is_app_limited field in the skb a boolean bit indicating whether there is a known "bubble in the pipe": a point in the rate sample interval where the sender was application-limited, and did not transmit even though the cwnd and pacing rate allowed it. This logic marks the flow app-limited on a write if *all* of the following are true: 1) There is less than 1 MSS of unsent data in the write queue available to transmit. 2) There is no packet in the sender's queues (e.g. in fq or the NIC tx queue). 3) The connection is not limited by cwnd. 4) There are no lost packets to retransmit. The tcp_rate_check_app_limited() code in tcp_rate.c determines whether the connection is application-limited at the moment. If the flow is application-limited, it sets the tp->app_limited field. If the flow is application-limited then that means there is effectively a "bubble" of silence in the pipe now, and this silence will be reflected in a lower bandwidth sample for any rate samples from now until we get an ACK indicating this bubble has exited the pipe: specifically, until we get an ACK for the next packet we transmit. When we send every skb we record in scb->tx.is_app_limited whether the resulting rate sample will be application-limited. The code in tcp_rate_gen() checks to see when it is safe to mark all known application-limited bubbles of silence as having exited the pipe. It does this by checking to see when the delivered count moves past the tp->app_limited marker. At this point it zeroes the tp->app_limited marker, as all known bubbles are out of the pipe. We make room for the tx.is_app_limited bit in the skb by borrowing a bit from the in_flight field used by NV to record the number of bytes in flight. The receive window in the TCP header is 16 bits, and the max receive window scaling shift factor is 14 (RFC 1323). So the max receive window offered by the TCP protocol is 2^(16+14) = 2^30. So we only need 30 bits for the tx.in_flight used by NV. Signed-off-by: Van Jacobson <vanj@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Nandita Dukkipati <nanditad@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b2d3ea4a |
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19-Sep-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: switch back to proper tcp_skb_cb size check in tcp_init() Revert to the tcp_skb_cb size check that tcp_init() had before commit b4772ef879a8 ("net: use common macro for assering skb->cb[] available size in protocol families"). As related commit 744d5a3e9fe2 ("net: move skb->dropcount to skb->cb[]") explains, the sock_skb_cb_check_size() mechanism was added to ensure that there is space for dropcount, "for protocol families using it". But TCP is not a protocol using dropcount, so tcp_init() doesn't need to provision space for dropcount in the skb->cb[], and thus we can revert to the older form of the tcp_skb_cb size check. Doing so allows TCP to use 4 more bytes of the skb->cb[] space. Fixes: b4772ef879a8 ("net: use common macro for assering skb->cb[] available size in protocol families") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
64033892 |
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19-Sep-2016 |
Neal Cardwell <ncardwell@google.com> |
tcp: use windowed min filter library for TCP min_rtt estimation Refactor the TCP min_rtt code to reuse the new win_minmax library in lib/win_minmax.c to simplify the TCP code. This is a pure refactor: the functionality is exactly the same. We just moved the windowed min code to make TCP easier to read and maintain, and to allow other parts of the kernel to use the windowed min/max filter code. Signed-off-by: Van Jacobson <vanj@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Nandita Dukkipati <nanditad@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3613b3db |
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15-Sep-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: prepare skbs for better sack shifting With large BDP TCP flows and lossy networks, it is very important to keep a low number of skbs in the write queue. RACK and SACK processing can perform a linear scan of it. We should avoid putting any payload in skb->head, so that SACK shifting can be done if needed. With this patch, we allow to pack ~0.5 MB per skb instead of the 64KB initially cooked at tcp_sendmsg() time. This gives a reduction of number of skbs in write queue by eight. tcp_rack_detect_loss() likes this. We still allow payload in skb->head for first skb put in the queue, to not impact RPC workloads. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9f5afeae |
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07-Sep-2016 |
Yaogong Wang <wygivan@google.com> |
tcp: use an RB tree for ooo receive queue Over the years, TCP BDP has increased by several orders of magnitude, and some people are considering to reach the 2 Gbytes limit. Even with current window scale limit of 14, ~1 Gbytes maps to ~740,000 MSS. In presence of packet losses (or reorders), TCP stores incoming packets into an out of order queue, and number of skbs sitting there waiting for the missing packets to be received can be in the 10^5 range. Most packets are appended to the tail of this queue, and when packets can finally be transferred to receive queue, we scan the queue from its head. However, in presence of heavy losses, we might have to find an arbitrary point in this queue, involving a linear scan for every incoming packet, throwing away cpu caches. This patch converts it to a RB tree, to get bounded latencies. Yaogong wrote a preliminary patch about 2 years ago. Eric did the rebase, added ofo_last_skb cache, polishing and tests. Tested with network dropping between 1 and 10 % packets, with good success (about 30 % increase of throughput in stress tests) Next step would be to also use an RB tree for the write queue at sender side ;) Signed-off-by: Yaogong Wang <wygivan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Acked-By: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
32035585 |
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28-Aug-2016 |
Tom Herbert <tom@herbertland.com> |
tcp: Set read_sock and peek_len proto_ops In inet_stream_ops we set read_sock to tcp_read_sock and peek_len to tcp_peek_len (which is just a stub function that calls tcp_inq). Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d7226c7a |
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23-Aug-2016 |
David Ahern <dsa@cumulusnetworks.com> |
net: diag: Fix refcnt leak in error path destroying socket inet_diag_find_one_icsk takes a reference to a socket that is not released if sock_diag_destroy returns an error. Fix by changing tcp_diag_destroy to manage the refcnt for all cases and remove the sock_put calls from tcp_abort. Fixes: c1e64e298b8ca ("net: diag: Support destroying TCP sockets") Reported-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b6c6b645 |
|
18-Aug-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: remove tcp_md5_hash_header() After commit 19689e38eca5 ("tcp: md5: use kmalloc() backed scratch areas") this function is no longer used. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
19689e38 |
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27-Jun-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: use kmalloc() backed scratch areas Some arches have virtually mapped kernel stacks, or will soon have. tcp_md5_hash_header() uses an automatic variable to copy tcp header before mangling th->check and calling crypto function, which might be problematic on such arches. David says that using percpu storage is also problematic on non SMP builds. Just use kmalloc() to allocate scratch areas. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b1ed4c4f |
|
27-Jun-2016 |
Andrey Vagin <avagin@openvz.org> |
tcp: add an ability to dump and restore window parameters We found that sometimes a restored tcp socket doesn't work. A reason of this bug is incorrect window parameters and in this case tcp_acceptable_seq() returns tcp_wnd_end(tp) instead of tp->snd_nxt. The other side drops packets with this seq, because seq is less than tp->rcv_nxt ( tcp_sequence() ). Data from a send queue is sent only if there is enough space in a window, so when we restore unacked data, we need to expand a window to fit this data. This was in a first version of this patch: "tcp: extend window to fit all restored unacked data in a send queue" Then Alexey recommended me to restore window parameters instead of adjusted them according with data in a sent queue. This sounds resonable. rcv_wnd has to be restored, because it was reported to another side and the offered window is never shrunk. One of reasons why we need to restore snd_wnd was described above. Cc: Pavel Emelyanov <xemul@parallels.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d4011239 |
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02-May-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: guarantee forward progress in tcp_sendmsg() Under high rx pressure, it is possible tcp_sendmsg() never has a chance to allocate an skb and loop forever as sk_flush_backlog() would always return true. Fix this by calling sk_flush_backlog() only if one skb had been allocated and filled before last backlog check. Fixes: d41a69f1d390 ("tcp: make tcp_sendmsg() aware of socket backlog") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d41a69f1 |
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29-Apr-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: make tcp_sendmsg() aware of socket backlog Large sendmsg()/write() hold socket lock for the duration of the call, unless sk->sk_sndbuf limit is hit. This is bad because incoming packets are parked into socket backlog for a long time. Critical decisions like fast retransmit might be delayed. Receivers have to maintain a big out of order queue with additional cpu overhead, and also possible stalls in TX once windows are full. Bidirectional flows are particularly hurt since the backlog can become quite big if the copy from user space triggers IO (page faults) Some applications learnt to use sendmsg() (or sendmmsg()) with small chunks to avoid this issue. Kernel should know better, right ? Add a generic sk_flush_backlog() helper and use it right before a new skb is allocated. Typically we put 64KB of payload per skb (unless MSG_EOR is requested) and checking socket backlog every 64KB gives good results. As a matter of fact, tests with TSO/GSO disabled give very nice results, as we manage to keep a small write queue and smaller perceived rtt. Note that sk_flush_backlog() maintains socket ownership, so is not equivalent to a {release_sock(sk); lock_sock(sk);}, to ensure implicit atomicity rules that sendmsg() was giving to (possibly buggy) applications. In this simple implementation, I chose to not call tcp_release_cb(), but we might consider this later. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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fb3477c0 |
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29-Apr-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: do not block bh during prequeue processing AFAIK, nothing in current TCP stack absolutely wants BH being disabled once socket is owned by a thread running in process context. As mentioned in my prior patch ("tcp: give prequeue mode some care"), processing a batch of packets might take time, better not block BH at all. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c10d9310 |
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29-Apr-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: do not assume TCP code is non preemptible We want to to make TCP stack preemptible, as draining prequeue and backlog queues can take lot of time. Many SNMP updates were assuming that BH (and preemption) was disabled. Need to convert some __NET_INC_STATS() calls to NET_INC_STATS() and some __TCP_INC_STATS() to TCP_INC_STATS() Before using this_cpu_ptr(net->ipv4.tcp_sk) in tcp_v4_send_reset() and tcp_v4_send_ack(), we add an explicit preempt disabled section. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c134ecb8 |
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25-Apr-2016 |
Martin KaFai Lau <kafai@fb.com> |
tcp: Make use of MSG_EOR in tcp_sendmsg This patch adds an eor bit to the TCP_SKB_CB. When MSG_EOR is passed to tcp_sendmsg, the eor bit will be set at the skb containing the last byte of the userland's msg. The eor bit will prevent data from appending to that skb in the future. The change in do_tcp_sendpages is to honor the eor set during the previous tcp_sendmsg(MSG_EOR) call. This patch handles the tcp_sendmsg case. The followup patches will handle other skb coalescing and fragment cases. One potential use case is to use MSG_EOR with SOF_TIMESTAMPING_TX_ACK to get a more accurate TCP ack timestamping on application protocol with multiple outgoing response messages (e.g. HTTP2). Packetdrill script for testing: ~~~~~~ +0 `sysctl -q -w net.ipv4.tcp_min_tso_segs=10` +0 `sysctl -q -w net.ipv4.tcp_no_metrics_save=1` +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 0.100 < S 0:0(0) win 32792 <mss 1460,sackOK,nop,nop,nop,wscale 7> 0.100 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 7> 0.200 < . 1:1(0) ack 1 win 257 0.200 accept(3, ..., ...) = 4 +0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0 0.200 write(4, ..., 14600) = 14600 0.200 sendto(4, ..., 730, MSG_EOR, ..., ...) = 730 0.200 sendto(4, ..., 730, MSG_EOR, ..., ...) = 730 0.200 > . 1:7301(7300) ack 1 0.200 > P. 7301:14601(7300) ack 1 0.300 < . 1:1(0) ack 14601 win 257 0.300 > P. 14601:15331(730) ack 1 0.300 > P. 15331:16061(730) ack 1 0.400 < . 1:1(0) ack 16061 win 257 0.400 close(4) = 0 0.400 > F. 16061:16061(0) ack 1 0.400 < F. 1:1(0) ack 16062 win 257 0.400 > . 16062:16062(0) ack 2 Signed-off-by: Martin KaFai Lau <kafai@fb.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Yuchung Cheng <ycheng@google.com> Suggested-by: Eric Dumazet <edumazet@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0a2cf20c |
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27-Apr-2016 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: remove SKBTX_ACK_TSTAMP since it is redundant The SKBTX_ACK_TSTAMP flag is set in skb_shinfo->tx_flags when the timestamp of the TCP acknowledgement should be reported on error queue. Since accessing skb_shinfo is likely to incur a cache-line miss at the time of receiving the ack, the txstamp_ack bit was added in tcp_skb_cb, which is set iff the SKBTX_ACK_TSTAMP flag is set for an skb. This makes SKBTX_ACK_TSTAMP flag redundant. Remove the SKBTX_ACK_TSTAMP and instead use the txstamp_ack bit everywhere. Note that this frees one bit in shinfo->tx_flags. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Suggested-by: Willem de Bruijn <willemb@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
863c1fd9 |
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27-Apr-2016 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: remove an unnecessary check in tcp_tx_timestamp Remove the redundant check for sk->sk_tsflags in tcp_tx_timestamp. tcp_tx_timestamp() receives the tsflags as a parameter. As a result the "sk->sk_tsflags || tsflags" is redundant, since tsflags already includes sk->sk_tsflags plus overrides from control messages. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
02a1d6e7 |
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27-Apr-2016 |
Eric Dumazet <edumazet@google.com> |
net: rename NET_{ADD|INC}_STATS_BH() Rename NET_INC_STATS_BH() to __NET_INC_STATS() and NET_ADD_STATS_BH() to __NET_ADD_STATS() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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90bbcc60 |
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27-Apr-2016 |
Eric Dumazet <edumazet@google.com> |
net: tcp: rename TCP_INC_STATS_BH Rename TCP_INC_STATS_BH() to __TCP_INC_STATS() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6aef70a8 |
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27-Apr-2016 |
Eric Dumazet <edumazet@google.com> |
net: snmp: kill various STATS_USER() helpers In the old days (before linux-3.0), SNMP counters were duplicated, one for user context, and one for BH context. After commit 8f0ea0fe3a03 ("snmp: reduce percpu needs by 50%") we have a single copy, and what really matters is preemption being enabled or disabled, since we use this_cpu_inc() or __this_cpu_inc() respectively. We therefore kill SNMP_INC_STATS_USER(), SNMP_ADD_STATS_USER(), NET_INC_STATS_USER(), NET_ADD_STATS_USER(), SCTP_INC_STATS_USER(), SNMP_INC_STATS64_USER(), SNMP_ADD_STATS64_USER(), TCP_ADD_STATS_USER(), UDP_INC_STATS_USER(), UDP6_INC_STATS_USER(), and XFRM_INC_STATS_USER() Following patches will rename __BH helpers to make clear their usage is not tied to BH being disabled. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c14ac945 |
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02-Apr-2016 |
Soheil Hassas Yeganeh <soheil@google.com> |
sock: enable timestamping using control messages Currently, SOL_TIMESTAMPING can only be enabled using setsockopt. This is very costly when users want to sample writes to gather tx timestamps. Add support for enabling SO_TIMESTAMPING via control messages by using tsflags added in `struct sockcm_cookie` (added in the previous patches in this series) to set the tx_flags of the last skb created in a sendmsg. With this patch, the timestamp recording bits in tx_flags of the skbuff is overridden if SO_TIMESTAMPING is passed in a cmsg. Please note that this is only effective for overriding the recording timestamps flags. Users should enable timestamp reporting (e.g., SOF_TIMESTAMPING_SOFTWARE | SOF_TIMESTAMPING_OPT_ID) using socket options and then should ask for SOF_TIMESTAMPING_TX_* using control messages per sendmsg to sample timestamps for each write. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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6b084928 |
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02-Apr-2016 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: use one bit in TCP_SKB_CB to mark ACK timestamps Currently, to avoid a cache line miss for accessing skb_shinfo, tcp_ack_tstamp skips socket that do not have SOF_TIMESTAMPING_TX_ACK bit set in sk_tsflags. This is implemented based on an implicit assumption that the SOF_TIMESTAMPING_TX_ACK is set via socket options for the duration that ACK timestamps are needed. To implement per-write timestamps, this check should be removed and replaced with a per-packet alternative that quickly skips packets missing ACK timestamps marks without a cache-line miss. To enable per-packet marking without a cache line miss, use one bit in TCP_SKB_CB to mark a whether a SKB might need a ack tx timestamp or not. Further checks in tcp_ack_tstamp are not modified and work as before. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a44d6eac |
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14-Mar-2016 |
Martin KaFai Lau <kafai@fb.com> |
tcp: Add RFC4898 tcpEStatsPerfDataSegsOut/In Per RFC4898, they count segments sent/received containing a positive length data segment (that includes retransmission segments carrying data). Unlike tcpi_segs_out/in, tcpi_data_segs_out/in excludes segments carrying no data (e.g. pure ack). The patch also updates the segs_in in tcp_fastopen_add_skb() so that segs_in >= data_segs_in property is kept. Together with retransmission data, tcpi_data_segs_out gives a better signal on the rxmit rate. v6: Rebase on the latest net-next v5: Eric pointed out that checking skb->len is still needed in tcp_fastopen_add_skb() because skb can carry a FIN without data. Hence, instead of open coding segs_in and data_segs_in, tcp_segs_in() helper is used. Comment is added to the fastopen case to explain why segs_in has to be reset and tcp_segs_in() has to be called before __skb_pull(). v4: Add comment to the changes in tcp_fastopen_add_skb() and also add remark on this case in the commit message. v3: Add const modifier to the skb parameter in tcp_segs_in() v2: Rework based on recent fix by Eric: commit a9d99ce28ed3 ("tcp: fix tcpi_segs_in after connection establishment") Signed-off-by: Martin KaFai Lau <kafai@fb.com> Cc: Chris Rapier <rapier@psc.edu> Cc: Eric Dumazet <edumazet@google.com> Cc: Marcelo Ricardo Leitner <mleitner@redhat.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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473bd239 |
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07-Mar-2016 |
Tom Herbert <tom@herbertland.com> |
tcp: Add tcp_inq to get available receive bytes on socket Create a common kernel function to get the number of bytes available on a TCP socket. This is based on code in INQ getsockopt and we now call the function for that getsockopt. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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1eea84b7 |
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15-Feb-2016 |
Insu Yun <wuninsu@gmail.com> |
tcp: correctly crypto_alloc_hash return check crypto_alloc_hash never returns NULL Signed-off-by: Insu Yun <wuninsu@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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cd9b2660 |
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11-Feb-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: add tcpi_min_rtt and tcpi_notsent_bytes to tcp_info tcpi_min_rtt reports the minimal rtt observed by TCP stack for the flow, in usec unit. Might be ~0U if not yet known. tcpi_notsent_bytes reports the amount of bytes in the write queue that were not yet sent. This is done in a single patch to not add a temporary 32bit padding hole in tcp_info. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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5f74f82e |
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03-Feb-2016 |
Hans Westgaard Ry <hans.westgaard.ry@oracle.com> |
net:Add sysctl_max_skb_frags Devices may have limits on the number of fragments in an skb they support. Current codebase uses a constant as maximum for number of fragments one skb can hold and use. When enabling scatter/gather and running traffic with many small messages the codebase uses the maximum number of fragments and may thereby violate the max for certain devices. The patch introduces a global variable as max number of fragments. Signed-off-by: Hans Westgaard Ry <hans.westgaard.ry@oracle.com> Reviewed-by: Håkon Bugge <haakon.bugge@oracle.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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1e579caa |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp_fin_timeout sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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1043e25f |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp reordering sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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6fa25166 |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp syn retries sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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9d691539 |
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01-Feb-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: do not enqueue skb with SYN flag If we remove the SYN flag from the skbs that tcp_fastopen_add_skb() places in socket receive queue, then we can remove the test that tcp_recvmsg() has to perform in fast path. All we have to do is to adjust SEQ in the slow path. For the moment, we place an unlikely() and output a message if we find an skb having SYN flag set. Goal would be to get rid of the test completely. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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ff5d7497 |
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27-Jan-2016 |
Eric Dumazet <edumazet@google.com> |
tcp: beware of alignments in tcp_get_info() With some combinations of user provided flags in netlink command, it is possible to call tcp_get_info() with a buffer that is not 8-bytes aligned. It does matter on some arches, so we need to use put_unaligned() to store the u64 fields. Current iproute2 package does not trigger this particular issue. Fixes: 0df48c26d841 ("tcp: add tcpi_bytes_acked to tcp_info") Fixes: 977cb0ecf82e ("tcp: add pacing_rate information into tcp_info") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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cf80e0e4 |
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24-Jan-2016 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp: Use ahash This patch replaces uses of the long obsolete hash interface with ahash. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: David S. Miller <davem@davemloft.net>
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3d596f7b |
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14-Jan-2016 |
Johannes Weiner <hannes@cmpxchg.org> |
net: tcp_memcontrol: protect all tcp_memcontrol calls by jump-label Move the jump-label from sock_update_memcg() and sock_release_memcg() to the callsite, and so eliminate those function calls when socket accounting is not enabled. This also eliminates the need for dummy functions because the calls will be optimized away if the Kconfig options are not enabled. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: David S. Miller <davem@davemloft.net> Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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2010b93e |
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21-Dec-2015 |
Lorenzo Colitti <lorenzo@google.com> |
net: tcp: deal with listen sockets properly in tcp_abort. When closing a listen socket, tcp_abort currently calls tcp_done without clearing the request queue. If the socket has a child socket that is established but not yet accepted, the child socket is then left without a parent, causing a leak. Fix this by setting the socket state to TCP_CLOSE and calling inet_csk_listen_stop with the socket lock held, like tcp_close does. Tested using net_test. With this patch, calling SOCK_DESTROY on a listen socket that has an established but not yet accepted child socket results in the parent and the child being closed, such that they no longer appear in sock_diag dumps. Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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07f6f4a3 |
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17-Dec-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: diag: add support for request sockets to tcp_abort() Adding support for SYN_RECV request sockets to tcp_abort() is quite easy after our tcp listener rewrite. Note that we also need to better handle listeners, or we might leak not yet accepted children, because of a missing inet_csk_listen_stop() call. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Lorenzo Colitti <lorenzo@google.com> Tested-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c1e64e29 |
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15-Dec-2015 |
Lorenzo Colitti <lorenzo@google.com> |
net: diag: Support destroying TCP sockets. This implements SOCK_DESTROY for TCP sockets. It causes all blocking calls on the socket to fail fast with ECONNABORTED and causes a protocol close of the socket. It informs the other end of the connection by sending a RST, i.e., initiating a TCP ABORT as per RFC 793. ECONNABORTED was chosen for consistency with FreeBSD. Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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9a49850d |
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14-Dec-2015 |
Tom Herbert <tom@herbertland.com> |
tcp: Fix conditions to determine checksum offload In tcp_send_sendpage and tcp_sendmsg we check the route capabilities to determine if checksum offload can be performed. This check currently does not take the IP protocol into account for devices that advertise only one of NETIF_F_IPV6_CSUM or NETIF_F_IP_CSUM. This patch adds a function to check capabilities for checksum offload with a socket called sk_check_csum_caps. This function checks for specific IPv4 or IPv6 offload support based on the family of the socket. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a188222b |
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14-Dec-2015 |
Tom Herbert <tom@herbertland.com> |
net: Rename NETIF_F_ALL_CSUM to NETIF_F_CSUM_MASK The name NETIF_F_ALL_CSUM is a misnomer. This does not correspond to the set of features for offloading all checksums. This is a mask of the checksum offload related features bits. It is incorrect to set both NETIF_F_HW_CSUM and NETIF_F_IP_CSUM or NETIF_F_IPV6 at the same time for features of a device. This patch: - Changes instances of NETIF_F_ALL_CSUM to NETIF_F_CSUM_MASK (where NETIF_F_ALL_CSUM is being used as a mask). - Changes bonding, sfc/efx, ipvlan, macvlan, vlan, and team drivers to use NEITF_F_HW_CSUM in features list instead of NETIF_F_ALL_CSUM. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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9cd3e072 |
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29-Nov-2015 |
Eric Dumazet <edumazet@google.com> |
net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA This patch is a cleanup to make following patch easier to review. Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA from (struct socket)->flags to a (struct socket_wq)->flags to benefit from RCU protection in sock_wake_async() To ease backports, we rename both constants. Two new helpers, sk_set_bit(int nr, struct sock *sk) and sk_clear_bit(int net, struct sock *sk) are added so that following patch can change their implementation. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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00fd38d9 |
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12-Nov-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: ensure proper barriers in lockless contexts Some functions access TCP sockets without holding a lock and might output non consistent data, depending on compiler and or architecture. tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ... Introduce sk_state_load() and sk_state_store() to fix the issues, and more clearly document where this lack of locking is happening. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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f6722583 |
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16-Oct-2015 |
Yuchung Cheng <ycheng@google.com> |
tcp: track min RTT using windowed min-filter Kathleen Nichols' algorithm for tracking the minimum RTT of a data stream over some measurement window. It uses constant space and constant time per update. Yet it almost always delivers the same minimum as an implementation that has to keep all the data in the window. The measurement window is tunable via sysctl.net.ipv4.tcp_min_rtt_wlen with a default value of 5 minutes. The algorithm keeps track of the best, 2nd best & 3rd best min values, maintaining an invariant that the measurement time of the n'th best >= n-1'th best. It also makes sure that the three values are widely separated in the time window since that bounds the worse case error when that data is monotonically increasing over the window. Upon getting a new min, we can forget everything earlier because it has no value - the new min is less than everything else in the window by definition and it's the most recent. So we restart fresh on every new min and overwrites the 2nd & 3rd choices. The same property holds for the 2nd & 3rd best. Therefore we have to maintain two invariants to maximize the information in the samples, one on values (1st.v <= 2nd.v <= 3rd.v) and the other on times (now-win <=1st.t <= 2nd.t <= 3rd.t <= now). These invariants determine the structure of the code The RTT input to the windowed filter is the minimum RTT measured from ACK or SACK, or as the last resort from TCP timestamps. The accessor tcp_min_rtt() returns the minimum RTT seen in the window. ~0U indicates it is not available. The minimum is 1usec even if the true RTT is below that. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
686a5624 |
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06-Oct-2015 |
Yuvaraja Mariappan <ymariappan@gmail.com> |
net: ipv4: tcp.c Fixed an assignment coding style issue Fixed an assignment coding style issue Signed-off-by: Yuvaraja Mariappan <ymariappan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0536fcc0 |
|
29-Sep-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: prepare fastopen code for upcoming listener changes While auditing TCP stack for upcoming 'lockless' listener changes, I found I had to change fastopen_init_queue() to properly init the object before publishing it. Otherwise an other cpu could try to lock the spinlock before it gets properly initialized. Instead of adding appropriate barriers, just remove dynamic memory allocations : - Structure is 28 bytes on 64bit arches. Using additional 8 bytes for holding a pointer seems overkill. - Two listeners can share same cache line and performance would suffer. If we really want to save few bytes, we would instead dynamically allocate whole struct request_sock_queue in the future. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6f021c62 |
|
21-Aug-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: fix slow start after idle vs TSO/GSO slow start after idle might reduce cwnd, but we perform this after first packet was cooked and sent. With TSO/GSO, it means that we might send a full TSO packet even if cwnd should have been reduced to IW10. Moving the SSAI check in skb_entail() makes sense, because we slightly reduce number of times this check is done, especially for large send() and TCP Small queue callbacks from softirq context. As Neal pointed out, we also need to perform the check if/when receive window opens. Tested: Following packetdrill test demonstrates the problem // Test of slow start after idle `sysctl -q net.ipv4.tcp_slow_start_after_idle=1` 0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 +0 < S 0:0(0) win 65535 <mss 1000,sackOK,nop,nop,nop,wscale 7> +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 6> +.100 < . 1:1(0) ack 1 win 511 +0 accept(3, ..., ...) = 4 +0 setsockopt(4, SOL_SOCKET, SO_SNDBUF, [200000], 4) = 0 +0 write(4, ..., 26000) = 26000 +0 > . 1:5001(5000) ack 1 +0 > . 5001:10001(5000) ack 1 +0 %{ assert tcpi_snd_cwnd == 10 }% +.100 < . 1:1(0) ack 10001 win 511 +0 %{ assert tcpi_snd_cwnd == 20, tcpi_snd_cwnd }% +0 > . 10001:20001(10000) ack 1 +0 > P. 20001:26001(6000) ack 1 +.100 < . 1:1(0) ack 26001 win 511 +0 %{ assert tcpi_snd_cwnd == 36, tcpi_snd_cwnd }% +4 write(4, ..., 20000) = 20000 // If slow start after idle works properly, we should send 5 MSS here (cwnd/2) +0 > . 26001:31001(5000) ack 1 +0 %{ assert tcpi_snd_cwnd == 10, tcpi_snd_cwnd }% +0 > . 31001:36001(5000) ack 1 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
dfbafc99 |
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24-Jul-2015 |
Sabrina Dubroca <sd@queasysnail.net> |
tcp: fix recv with flags MSG_WAITALL | MSG_PEEK Currently, tcp_recvmsg enters a busy loop in sk_wait_data if called with flags = MSG_WAITALL | MSG_PEEK. sk_wait_data waits for sk_receive_queue not empty, but in this case, the receive queue is not empty, but does not contain any skb that we can use. Add a "last skb seen on receive queue" argument to sk_wait_data, so that it sleeps until the receive queue has new skbs. Link: https://bugzilla.kernel.org/show_bug.cgi?id=99461 Link: https://sourceware.org/bugzilla/show_bug.cgi?id=18493 Link: https://bugzilla.redhat.com/show_bug.cgi?id=1205258 Reported-by: Enrico Scholz <rh-bugzilla@ensc.de> Reported-by: Dan Searle <dan@censornet.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
dfea2aa6 |
|
18-Jun-2015 |
Christoph Paasch <cpaasch@apple.com> |
tcp: Do not call tcp_fastopen_reset_cipher from interrupt context tcp_fastopen_reset_cipher really cannot be called from interrupt context. It allocates the tcp_fastopen_context with GFP_KERNEL and calls crypto_alloc_cipher, which allocates all kind of stuff with GFP_KERNEL. Thus, we might sleep when the key-generation is triggered by an incoming TFO cookie-request which would then happen in interrupt- context, as shown by enabling CONFIG_DEBUG_ATOMIC_SLEEP: [ 36.001813] BUG: sleeping function called from invalid context at mm/slub.c:1266 [ 36.003624] in_atomic(): 1, irqs_disabled(): 0, pid: 1016, name: packetdrill [ 36.004859] CPU: 1 PID: 1016 Comm: packetdrill Not tainted 4.1.0-rc7 #14 [ 36.006085] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014 [ 36.008250] 00000000000004f2 ffff88007f8838a8 ffffffff8171d53a ffff880075a084a8 [ 36.009630] ffff880075a08000 ffff88007f8838c8 ffffffff810967d3 ffff88007f883928 [ 36.011076] 0000000000000000 ffff88007f8838f8 ffffffff81096892 ffff88007f89be00 [ 36.012494] Call Trace: [ 36.012953] <IRQ> [<ffffffff8171d53a>] dump_stack+0x4f/0x6d [ 36.014085] [<ffffffff810967d3>] ___might_sleep+0x103/0x170 [ 36.015117] [<ffffffff81096892>] __might_sleep+0x52/0x90 [ 36.016117] [<ffffffff8118e887>] kmem_cache_alloc_trace+0x47/0x190 [ 36.017266] [<ffffffff81680d82>] ? tcp_fastopen_reset_cipher+0x42/0x130 [ 36.018485] [<ffffffff81680d82>] tcp_fastopen_reset_cipher+0x42/0x130 [ 36.019679] [<ffffffff81680f01>] tcp_fastopen_init_key_once+0x61/0x70 [ 36.020884] [<ffffffff81680f2c>] __tcp_fastopen_cookie_gen+0x1c/0x60 [ 36.022058] [<ffffffff816814ff>] tcp_try_fastopen+0x58f/0x730 [ 36.023118] [<ffffffff81671788>] tcp_conn_request+0x3e8/0x7b0 [ 36.024185] [<ffffffff810e3872>] ? __module_text_address+0x12/0x60 [ 36.025327] [<ffffffff8167b2e1>] tcp_v4_conn_request+0x51/0x60 [ 36.026410] [<ffffffff816727e0>] tcp_rcv_state_process+0x190/0xda0 [ 36.027556] [<ffffffff81661f97>] ? __inet_lookup_established+0x47/0x170 [ 36.028784] [<ffffffff8167c2ad>] tcp_v4_do_rcv+0x16d/0x3d0 [ 36.029832] [<ffffffff812e6806>] ? security_sock_rcv_skb+0x16/0x20 [ 36.030936] [<ffffffff8167cc8a>] tcp_v4_rcv+0x77a/0x7b0 [ 36.031875] [<ffffffff816af8c3>] ? iptable_filter_hook+0x33/0x70 [ 36.032953] [<ffffffff81657d22>] ip_local_deliver_finish+0x92/0x1f0 [ 36.034065] [<ffffffff81657f1a>] ip_local_deliver+0x9a/0xb0 [ 36.035069] [<ffffffff81657c90>] ? ip_rcv+0x3d0/0x3d0 [ 36.035963] [<ffffffff81657569>] ip_rcv_finish+0x119/0x330 [ 36.036950] [<ffffffff81657ba7>] ip_rcv+0x2e7/0x3d0 [ 36.037847] [<ffffffff81610652>] __netif_receive_skb_core+0x552/0x930 [ 36.038994] [<ffffffff81610a57>] __netif_receive_skb+0x27/0x70 [ 36.040033] [<ffffffff81610b72>] process_backlog+0xd2/0x1f0 [ 36.041025] [<ffffffff81611482>] net_rx_action+0x122/0x310 [ 36.042007] [<ffffffff81076743>] __do_softirq+0x103/0x2f0 [ 36.042978] [<ffffffff81723e3c>] do_softirq_own_stack+0x1c/0x30 This patch moves the call to tcp_fastopen_init_key_once to the places where a listener socket creates its TFO-state, which always happens in user-context (either from the setsockopt, or implicitly during the listen()-call) Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Fixes: 222e83d2e0ae ("tcp: switch tcp_fastopen key generation to net_get_random_once") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
35ac838a |
|
15-Jun-2015 |
Craig Gallek <kraig@google.com> |
sock_diag: implement a get_info handler for inet This get_info handler will simply dispatch to the appropriate existing inet protocol handler. This patch also includes a new netlink attribute (INET_DIAG_PROTOCOL). This attribute is currently only used for multicast messages. Without this attribute, there is no way of knowing the IP protocol used by the socket information being broadcast. This attribute is not necessary in the 'dump' variant of this protocol (though it could easily be added) because dump requests are issued for specific family/protocol pairs. Tested: ss -E (note, the -E option has not yet been merged into the upstream version of ss). Signed-off-by: Craig Gallek <kraig@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a60e3cc7 |
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21-May-2015 |
Hannes Frederic Sowa <hannes@stressinduktion.org> |
net: make skb_splice_bits more configureable Prepare skb_splice_bits to be able to deal with AF_UNIX sockets. AF_UNIX sockets don't use lock_sock/release_sock and thus we have to use a callback to make the locking and unlocking configureable. Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d654976c |
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21-May-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: fix a potential deadlock in tcp_get_info() Taking socket spinlock in tcp_get_info() can deadlock, as inet_diag_dump_icsk() holds the &hashinfo->ehash_locks[i], while packet processing can use the reverse locking order. We could avoid this locking for TCP_LISTEN states, but lockdep would certainly get confused as all TCP sockets share same lockdep classes. [ 523.722504] ====================================================== [ 523.728706] [ INFO: possible circular locking dependency detected ] [ 523.734990] 4.1.0-dbg-DEV #1676 Not tainted [ 523.739202] ------------------------------------------------------- [ 523.745474] ss/18032 is trying to acquire lock: [ 523.750002] (slock-AF_INET){+.-...}, at: [<ffffffff81669d44>] tcp_get_info+0x2c4/0x360 [ 523.758129] [ 523.758129] but task is already holding lock: [ 523.763968] (&(&hashinfo->ehash_locks[i])->rlock){+.-...}, at: [<ffffffff816bcb75>] inet_diag_dump_icsk+0x1d5/0x6c0 [ 523.774661] [ 523.774661] which lock already depends on the new lock. [ 523.774661] [ 523.782850] [ 523.782850] the existing dependency chain (in reverse order) is: [ 523.790326] -> #1 (&(&hashinfo->ehash_locks[i])->rlock){+.-...}: [ 523.796599] [<ffffffff811126bb>] lock_acquire+0xbb/0x270 [ 523.802565] [<ffffffff816f5868>] _raw_spin_lock+0x38/0x50 [ 523.808628] [<ffffffff81665af8>] __inet_hash_nolisten+0x78/0x110 [ 523.815273] [<ffffffff816819db>] tcp_v4_syn_recv_sock+0x24b/0x350 [ 523.822067] [<ffffffff81684d41>] tcp_check_req+0x3c1/0x500 [ 523.828199] [<ffffffff81682d09>] tcp_v4_do_rcv+0x239/0x3d0 [ 523.834331] [<ffffffff816842fe>] tcp_v4_rcv+0xa8e/0xc10 [ 523.840202] [<ffffffff81658fa3>] ip_local_deliver_finish+0x133/0x3e0 [ 523.847214] [<ffffffff81659a9a>] ip_local_deliver+0xaa/0xc0 [ 523.853440] [<ffffffff816593b8>] ip_rcv_finish+0x168/0x5c0 [ 523.859624] [<ffffffff81659db7>] ip_rcv+0x307/0x420 Lets use u64_sync infrastructure instead. As a bonus, 64bit arches get optimized, as these are nop for them. Fixes: 0df48c26d841 ("tcp: add tcpi_bytes_acked to tcp_info") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2efd055c |
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20-May-2015 |
Marcelo Ricardo Leitner <mleitner@redhat.com> |
tcp: add tcpi_segs_in and tcpi_segs_out to tcp_info This patch tracks the total number of inbound and outbound segments on a TCP socket. One may use this number to have an idea on connection quality when compared against the retransmissions. RFC4898 named these : tcpEStatsPerfSegsIn and tcpEStatsPerfSegsOut These are a 32bit field each and can be fetched both from TCP_INFO getsockopt() if one has a handle on a TCP socket, or from inet_diag netlink facility (iproute2/ss patch will follow) Note that tp->segs_out was placed near tp->snd_nxt for good data locality and minimal performance impact, while tp->segs_in was placed near tp->bytes_received for the same reason. Join work with Eric Dumazet. Note that received SYN are accounted on the listener, but sent SYNACK are not accounted. Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ce5ec440 |
|
20-May-2015 |
Jason Baron <jbaron@akamai.com> |
tcp: ensure epoll edge trigger wakeup when write queue is empty We currently rely on the setting of SOCK_NOSPACE in the write() path to ensure that we wake up any epoll edge trigger waiters when acks return to free space in the write queue. However, if we fail to allocate even a single skb in the write queue, we could end up waiting indefinitely. Fix this by explicitly issuing a wakeup when we detect the condition of an empty write queue and a return value of -EAGAIN. This allows userspace to re-try as we expect this to be a temporary failure. I've tested this approach by artificially making sk_stream_alloc_skb() return NULL periodically. In that case, epoll edge trigger waiters will hang indefinitely in epoll_wait() without this patch. Signed-off-by: Jason Baron <jbaron@akamai.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
eb934478 |
|
19-May-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: add a force_schedule argument to sk_stream_alloc_skb() In commit 8e4d980ac215 ("tcp: fix behavior for epoll edge trigger") we fixed a possible hang of TCP sockets under memory pressure, by allowing sk_stream_alloc_skb() to use sk_forced_mem_schedule() if no packet is in socket write queue. It turns out there are other cases where we want to force memory schedule : tcp_fragment() & tso_fragment() need to split a big TSO packet into two smaller ones. If we block here because of TCP memory pressure, we can effectively block TCP socket from sending new data. If no further ACK is coming, this hang would be definitive, and socket has no chance to effectively reduce its memory usage. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
aea0929e |
|
18-May-2015 |
Eric B Munson <emunson@akamai.com> |
tcp: Return error instead of partial read for saved syn headers Currently the getsockopt() requesting the cached contents of the syn packet headers will fail silently if the caller uses a buffer that is too small to contain the requested data. Rather than fail silently and discard the headers, getsockopt() should return an error and report the required size to hold the data. Signed-off-by: Eric B Munson <emunson@akamai.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b66e91cc |
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15-May-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: halves tcp_mem[] limits Allowing tcp to use ~19% of physical memory is way too much, and allowed bugs to be hidden. Add to this that some drivers use a full page per incoming frame, so real cost can be twice the advertized one. Reduce tcp_mem by 50 % as a first step to sanity. tcp_mem[0,1,2] defaults are now 4.68%, 6.25%, 9.37% of physical memory. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8e4d980a |
|
15-May-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: fix behavior for epoll edge trigger Under memory pressure, tcp_sendmsg() can fail to queue a packet while no packet is present in write queue. If we return -EAGAIN with no packet in write queue, no ACK packet will ever come to raise EPOLLOUT. We need to allow one skb per TCP socket, and make sure that tcp sockets can release their forward allocations under pressure. This is a followup to commit 790ba4566c1a ("tcp: set SOCK_NOSPACE under memory pressure") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cd8ae852 |
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03-May-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: provide SYN headers for passive connections This patch allows a server application to get the TCP SYN headers for its passive connections. This is useful if the server is doing fingerprinting of clients based on SYN packet contents. Two socket options are added: TCP_SAVE_SYN and TCP_SAVED_SYN. The first is used on a socket to enable saving the SYN headers for child connections. This can be set before or after the listen() call. The latter is used to retrieve the SYN headers for passive connections, if the parent listener has enabled TCP_SAVE_SYN. TCP_SAVED_SYN is read once, it frees the saved SYN headers. The data returned in TCP_SAVED_SYN are network (IPv4/IPv6) and TCP headers. Original patch was written by Tom Herbert, I changed it to not hold a full skb (and associated dst and conntracking reference). We have used such patch for about 3 years at Google. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Tested-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6e9250f5 |
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28-Apr-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: add TCP_CC_INFO socket option Some Congestion Control modules can provide per flow information, but current way to get this information is to use netlink. Like TCP_INFO, let's add TCP_CC_INFO so that applications can issue a getsockopt() if they have a socket file descriptor, instead of playing complex netlink games. Sample usage would be : union tcp_cc_info info; socklen_t len = sizeof(info); if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1) Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bdd1f9ed |
|
28-Apr-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: add tcpi_bytes_received to tcp_info This patch tracks total number of payload bytes received on a TCP socket. This is the sum of all changes done to tp->rcv_nxt RFC4898 named this : tcpEStatsAppHCThruOctetsReceived This is a 64bit field, and can be fetched both from TCP_INFO getsockopt() if one has a handle on a TCP socket, or from inet_diag netlink facility (iproute2/ss patch will follow) Note that tp->bytes_received was placed near tp->rcv_nxt for best data locality and minimal performance impact. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Matt Mathis <mattmathis@google.com> Cc: Eric Salo <salo@google.com> Cc: Martin Lau <kafai@fb.com> Cc: Chris Rapier <rapier@psc.edu> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0df48c26 |
|
28-Apr-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: add tcpi_bytes_acked to tcp_info This patch tracks total number of bytes acked for a TCP socket. This is the sum of all changes done to tp->snd_una, and allows for precise tracking of delivered data. RFC4898 named this : tcpEStatsAppHCThruOctetsAcked This is a 64bit field, and can be fetched both from TCP_INFO getsockopt() if one has a handle on a TCP socket, or from inet_diag netlink facility (iproute2/ss patch will follow) Note that tp->bytes_acked was placed near tp->snd_una for best data locality and minimal performance impact. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Cc: Matt Mathis <mattmathis@google.com> Cc: Eric Salo <salo@google.com> Cc: Martin Lau <kafai@fb.com> Cc: Chris Rapier <rapier@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3c715127 |
|
20-Apr-2015 |
jbaron@akamai.com <jbaron@akamai.com> |
tcp: add memory barriers to write space paths Ensure that we either see that the buffer has write space in tcp_poll() or that we perform a wakeup from the input side. Did not run into any actual problem here, but thought that we should make things explicit. Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fad9dfef |
|
16-Apr-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: tcp_get_info() should fetch socket fields once tcp_get_info() can be called without holding socket lock, so any socket fields can change under us. Use READ_ONCE() to fetch sk_pacing_rate and sk_max_pacing_rate Fixes: 977cb0ecf82e ("tcp: add pacing_rate information into tcp_info") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
01e97e65 |
|
15-Dec-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
new helper: msg_data_left() convert open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
00db4124 |
|
03-Apr-2015 |
Ian Morris <ipm@chirality.org.uk> |
ipv4: coding style: comparison for inequality with NULL The ipv4 code uses a mixture of coding styles. In some instances check for non-NULL pointer is done as x != NULL and sometimes as x. x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
51456b29 |
|
03-Apr-2015 |
Ian Morris <ipm@chirality.org.uk> |
ipv4: coding style: comparison for equality with NULL The ipv4 code uses a mixture of coding styles. In some instances check for NULL pointer is done as x == NULL and sometimes as !x. !x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0980c1e3 |
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24-Mar-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: use C99 initializers in new_state[] Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6c09fa09 |
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05-Mar-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: align tcp_xmit_size_goal() on tcp_tso_autosize() With some mss values, it is possible tcp_xmit_size_goal() puts one segment more in TSO packet than tcp_tso_autosize(). We send then one TSO packet followed by one single MSS. It is not a serious bug, but we can do slightly better, especially for drivers using netif_set_gso_max_size() to lower gso_max_size. Using same formula avoids these corner cases and makes tcp_xmit_size_goal() a bit faster. Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: 605ad7f184b6 ("tcp: refine TSO autosizing") Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1b784140 |
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02-Mar-2015 |
Ying Xue <ying.xue@windriver.com> |
net: Remove iocb argument from sendmsg and recvmsg After TIPC doesn't depend on iocb argument in its internal implementations of sendmsg() and recvmsg() hooks defined in proto structure, no any user is using iocb argument in them at all now. Then we can drop the redundant iocb argument completely from kinds of implementations of both sendmsg() and recvmsg() in the entire networking stack. Cc: Christoph Hellwig <hch@lst.de> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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b4772ef8 |
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01-Mar-2015 |
Eyal Birger <eyal.birger@gmail.com> |
net: use common macro for assering skb->cb[] available size in protocol families As part of an effort to move skb->dropcount to skb->cb[] use a common macro in protocol families using skb->cb[] for ancillary data to validate available room in skb->cb[]. Signed-off-by: Eyal Birger <eyal.birger@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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57be5bda |
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28-Nov-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
ip: convert tcp_sendmsg() to iov_iter primitives patch is actually smaller than it seems to be - most of it is unindenting the inner loop body in tcp_sendmsg() itself... the bit in tcp_input.c is going to get reverted very soon - that's what memcpy_from_msg() will become, but not in this commit; let's keep it reasonably contained... There's one potentially subtle change here: in case of short copy from userland, mainline tcp_send_syn_data() discards the skb it has allocated and falls back to normal path, where we'll send as much as possible after rereading the same data again. This patch trims SYN+data skb instead - that way we don't need to copy from the same place twice. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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605ad7f1 |
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07-Dec-2014 |
Eric Dumazet <edumazet@google.com> |
tcp: refine TSO autosizing Commit 95bd09eb2750 ("tcp: TSO packets automatic sizing") tried to control TSO size, but did this at the wrong place (sendmsg() time) At sendmsg() time, we might have a pessimistic view of flow rate, and we end up building very small skbs (with 2 MSS per skb). This is bad because : - It sends small TSO packets even in Slow Start where rate quickly increases. - It tends to make socket write queue very big, increasing tcp_ack() processing time, but also increasing memory needs, not necessarily accounted for, as fast clones overhead is currently ignored. - Lower GRO efficiency and more ACK packets. Servers with a lot of small lived connections suffer from this. Lets instead fill skbs as much as possible (64KB of payload), but split them at xmit time, when we have a precise idea of the flow rate. skb split is actually quite efficient. Patch looks bigger than necessary, because TCP Small Queue decision now has to take place after the eventual split. As Neal suggested, introduce a new tcp_tso_autosize() helper, so that tcp_tso_should_defer() can be synchronized on same goal. Rename tp->xmit_size_goal_segs to tp->gso_segs, as this variable contains number of mss that we can put in GSO packet, and is not related to the autosizing goal anymore. Tested: 40 ms rtt link nstat >/dev/null netperf -H remote -l -2000000 -- -s 1000000 nstat | egrep "IpInReceives|IpOutRequests|TcpOutSegs|IpExtOutOctets" Before patch : Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/s 87380 2000000 2000000 0.36 44.22 IpInReceives 600 0.0 IpOutRequests 599 0.0 TcpOutSegs 1397 0.0 IpExtOutOctets 2033249 0.0 After patch : Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 2000000 2000000 0.36 44.27 IpInReceives 221 0.0 IpOutRequests 232 0.0 TcpOutSegs 1397 0.0 IpExtOutOctets 2013953 0.0 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c0371da6 |
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24-Nov-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
put iov_iter into msghdr Note that the code _using_ ->msg_iter at that point will be very unhappy with anything other than unshifted iovec-backed iov_iter. We still need to convert users to proper primitives. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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f4362a2c |
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24-Nov-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
switch tcp_sock->ucopy from iovec (ucopy.iov) to msghdr (ucopy.msg) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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f4713a3d |
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26-Nov-2014 |
Willem de Bruijn <willemb@google.com> |
net-timestamp: make tcp_recvmsg call ipv6_recv_error for AF_INET6 socks TCP timestamping introduced MSG_ERRQUEUE handling for TCP sockets. If the socket is of family AF_INET6, call ipv6_recv_error instead of ip_recv_error. This change is more complex than a single branch due to the loadable ipv6 module. It reuses a pre-existing indirect function call from ping. The ping code is safe to call, because it is part of the core ipv6 module and always present when AF_INET6 sockets are active. Fixes: 4ed2d765 (net-timestamp: TCP timestamping) Signed-off-by: Willem de Bruijn <willemb@google.com> ---- It may also be worthwhile to add WARN_ON_ONCE(sk->family == AF_INET6) to ip_recv_error. Signed-off-by: David S. Miller <davem@davemloft.net>
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7eab8d9e |
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06-Apr-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
new helper: memcpy_to_msg() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
51f3d02b |
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05-Nov-2014 |
David S. Miller <davem@davemloft.net> |
net: Add and use skb_copy_datagram_msg() helper. This encapsulates all of the skb_copy_datagram_iovec() callers with call argument signature "skb, offset, msghdr->msg_iov, length". When we move to iov_iters in the networking, the iov_iter object will sit in the msghdr. Having a helper like this means there will be less places to touch during that transformation. Based upon descriptions and patch from Al Viro. Signed-off-by: David S. Miller <davem@davemloft.net>
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349ce993 |
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23-Oct-2014 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: do not use alloc_percpu() percpu tcp_md5sig_pool contains memory blobs that ultimately go through sg_set_buf(). -> sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf)); This requires that whole area is in a physically contiguous portion of memory. And that @buf is not backed by vmalloc(). Given that alloc_percpu() can use vmalloc() areas, this does not fit the requirements. Replace alloc_percpu() by a static DEFINE_PER_CPU() as tcp_md5sig_pool is small anyway, there is no gain to dynamically allocate it. Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: 765cf9976e93 ("tcp: md5: remove one indirection level in tcp_md5sig_pool") Reported-by: Crestez Dan Leonard <cdleonard@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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b248230c |
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29-Sep-2014 |
Yuchung Cheng <ycheng@google.com> |
tcp: abort orphan sockets stalling on zero window probes Currently we have two different policies for orphan sockets that repeatedly stall on zero window ACKs. If a socket gets a zero window ACK when it is transmitting data, the RTO is used to probe the window. The socket is aborted after roughly tcp_orphan_retries() retries (as in tcp_write_timeout()). But if the socket was idle when it received the zero window ACK, and later wants to send more data, we use the probe timer to probe the window. If the receiver always returns zero window ACKs, icsk_probes keeps getting reset in tcp_ack() and the orphan socket can stall forever until the system reaches the orphan limit (as commented in tcp_probe_timer()). This opens up a simple attack to create lots of hanging orphan sockets to burn the memory and the CPU, as demonstrated in the recent netdev post "TCP connection will hang in FIN_WAIT1 after closing if zero window is advertised." http://www.spinics.net/lists/netdev/msg296539.html This patch follows the design in RTO-based probe: we abort an orphan socket stalling on zero window when the probe timer reaches both the maximum backoff and the maximum RTO. For example, an 100ms RTT connection will timeout after roughly 153 seconds (0.3 + 0.6 + .... + 76.8) if the receiver keeps the window shut. If the orphan socket passes this check, but the system already has too many orphans (as in tcp_out_of_resources()), we still abort it but we'll also send an RST packet as the connection may still be active. In addition, we change TCP_USER_TIMEOUT to cover (life or dead) sockets stalled on zero-window probes. This changes the semantics of TCP_USER_TIMEOUT slightly because it previously only applies when the socket has pending transmission. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Reported-by: Andrey Dmitrov <andrey.dmitrov@oktetlabs.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
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47d7a88c |
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01-Oct-2014 |
Fabian Frederick <fabf@skynet.be> |
tcp: add __init to tcp_init_mem tcp_init_mem is only called by __init tcp_init. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: David S. Miller <davem@davemloft.net>
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55d8694f |
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26-Sep-2014 |
Florian Westphal <fw@strlen.de> |
net: tcp: assign tcp cong_ops when tcp sk is created Split assignment and initialization from one into two functions. This is required by followup patches that add Datacenter TCP (DCTCP) congestion control algorithm - we need to be able to determine if the connection is moderated by DCTCP before the 3WHS has finished. As we walk the available congestion control list during the assignment, we are always guaranteed to have Reno present as it's fixed compiled-in. Therefore, since we're doing the early assignment, we don't have a real use for the Reno alias tcp_init_congestion_ops anymore and can thus remove it. Actual usage of the congestion control operations are being made after the 3WHS has finished, in some cases however we can access get_info() via diag if implemented, therefore we need to zero out the private area for those modules. Joint work with Daniel Borkmann and Glenn Judd. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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cd7d8498 |
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24-Sep-2014 |
Eric Dumazet <edumazet@google.com> |
tcp: change tcp_skb_pcount() location Our goal is to access no more than one cache line access per skb in a write or receive queue when doing the various walks. After recent TCP_SKB_CB() reorganizations, it is almost done. Last part is tcp_skb_pcount() which currently uses skb_shinfo(skb)->gso_segs, which is a terrible choice, because it needs 3 cache lines in current kernel (skb->head, skb->end, and shinfo->gso_segs are all in 3 different cache lines, far from skb->cb) This very simple patch reuses space currently taken by tcp_tw_isn only in input path, as tcp_skb_pcount is only needed for skb stored in write queue. This considerably speeds up tcp_ack(), granted we avoid shinfo->tx_flags to get SKBTX_ACK_TSTAMP, which seems possible. This also speeds up all sack processing in general. This speeds up tcp_sendmsg() because it no longer has to access/dirty shinfo. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3f334078 |
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30-Dec-2013 |
Dan Williams <dan.j.williams@intel.com> |
net: make tcp_cleanup_rbuf private net_dma was the only external user so this can become local to tcp.c again. Cc: James Morris <jmorris@namei.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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7bced397 |
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30-Dec-2013 |
Dan Williams <dan.j.williams@intel.com> |
net_dma: simple removal Per commit "77873803363c net_dma: mark broken" net_dma is no longer used and there is no plan to fix it. This is the mechanical removal of bits in CONFIG_NET_DMA ifdef guards. Reverting the remainder of the net_dma induced changes is deferred to subsequent patches. Marked for stable due to Roman's report of a memory leak in dma_pin_iovec_pages(): https://lkml.org/lkml/2014/9/3/177 Cc: Dave Jiang <dave.jiang@intel.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: David Whipple <whipple@securedatainnovations.ch> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Cc: <stable@vger.kernel.org> Reported-by: Roman Gushchin <klamm@yandex-team.ru> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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f4a775d1 |
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22-Sep-2014 |
Eric Dumazet <edumazet@google.com> |
net: introduce __skb_header_release() While profiling TCP stack, I noticed one useless atomic operation in tcp_sendmsg(), caused by skb_header_release(). It turns out all current skb_header_release() users have a fresh skb, that no other user can see, so we can avoid one atomic operation. Introduce __skb_header_release() to clearly document this. This gave me a 1.5 % improvement on TCP_RR workload. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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e11ecddf |
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15-Sep-2014 |
Eric Dumazet <edumazet@google.com> |
tcp: use TCP_SKB_CB(skb)->tcp_flags in input path Input path of TCP do not currently uses TCP_SKB_CB(skb)->tcp_flags, which is only used in output path. tcp_recvmsg(), looks at tcp_hdr(skb)->syn for every skb found in receive queue, and its unfortunate because this bit is located in a cache line right before the payload. We can simplify TCP by copying tcp flags into TCP_SKB_CB(skb)->tcp_flags. This patch does so, and avoids the cache line miss in tcp_recvmsg() Following patches will - allow a segment with FIN being coalesced in tcp_try_coalesce() - simplify tcp_collapse() by not copying the headers. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
908c7f19 |
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07-Sep-2014 |
Tejun Heo <tj@kernel.org> |
percpu_counter: add @gfp to percpu_counter_init() Percpu allocator now supports allocation mask. Add @gfp to percpu_counter_init() so that !GFP_KERNEL allocation masks can be used with percpu_counters too. We could have left percpu_counter_init() alone and added percpu_counter_init_gfp(); however, the number of users isn't that high and introducing _gfp variants to all percpu data structures would be quite ugly, so let's just do the conversion. This is the one with the most users. Other percpu data structures are a lot easier to convert. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jan Kara <jack@suse.cz> Acked-by: "David S. Miller" <davem@davemloft.net> Cc: x86@kernel.org Cc: Jens Axboe <axboe@kernel.dk> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org>
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903ceff7 |
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16-Aug-2014 |
Christoph Lameter <cl@linux.com> |
net: Replace get_cpu_var through this_cpu_ptr Replace uses of get_cpu_var for address calculation through this_cpu_ptr. Cc: netdev@vger.kernel.org Cc: Eric Dumazet <edumazet@google.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
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9d186cac |
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13-Aug-2014 |
Andrey Vagin <avagin@openvz.org> |
tcp: don't use timestamp from repaired skb-s to calculate RTT (v2) We don't know right timestamp for repaired skb-s. Wrong RTT estimations isn't good, because some congestion modules heavily depends on it. This patch adds the TCPCB_REPAIRED flag, which is included in TCPCB_RETRANS. Thanks to Eric for the advice how to fix this issue. This patch fixes the warning: [ 879.562947] WARNING: CPU: 0 PID: 2825 at net/ipv4/tcp_input.c:3078 tcp_ack+0x11f5/0x1380() [ 879.567253] CPU: 0 PID: 2825 Comm: socket-tcpbuf-l Not tainted 3.16.0-next-20140811 #1 [ 879.567829] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 879.568177] 0000000000000000 00000000c532680c ffff880039643d00 ffffffff817aa2d2 [ 879.568776] 0000000000000000 ffff880039643d38 ffffffff8109afbd ffff880039d6ba80 [ 879.569386] ffff88003a449800 000000002983d6bd 0000000000000000 000000002983d6bc [ 879.569982] Call Trace: [ 879.570264] [<ffffffff817aa2d2>] dump_stack+0x4d/0x66 [ 879.570599] [<ffffffff8109afbd>] warn_slowpath_common+0x7d/0xa0 [ 879.570935] [<ffffffff8109b0ea>] warn_slowpath_null+0x1a/0x20 [ 879.571292] [<ffffffff816d0a05>] tcp_ack+0x11f5/0x1380 [ 879.571614] [<ffffffff816d10bd>] tcp_rcv_established+0x1ed/0x710 [ 879.571958] [<ffffffff816dc9da>] tcp_v4_do_rcv+0x10a/0x370 [ 879.572315] [<ffffffff81657459>] release_sock+0x89/0x1d0 [ 879.572642] [<ffffffff816c81a0>] do_tcp_setsockopt.isra.36+0x120/0x860 [ 879.573000] [<ffffffff8110a52e>] ? rcu_read_lock_held+0x6e/0x80 [ 879.573352] [<ffffffff816c8912>] tcp_setsockopt+0x32/0x40 [ 879.573678] [<ffffffff81654ac4>] sock_common_setsockopt+0x14/0x20 [ 879.574031] [<ffffffff816537b0>] SyS_setsockopt+0x80/0xf0 [ 879.574393] [<ffffffff817b40a9>] system_call_fastpath+0x16/0x1b [ 879.574730] ---[ end trace a17cbc38eb8c5c00 ]--- v2: moving setting of skb->when for repaired skb-s in tcp_write_xmit, where it's set for other skb-s. Fixes: 431a91242d8d ("tcp: timestamp SYN+DATA messages") Fixes: 740b0f1841f6 ("tcp: switch rtt estimations to usec resolution") Cc: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f066e2b0 |
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06-Aug-2014 |
Willem de Bruijn <willemb@google.com> |
net-timestamp: cumulative tcp timestamping fixes A set of small fixes pointed out just after the merge: - make tcp_tx_timestamp static - make tcp_gso_tstamp static - use before() to compare TCP seqno, instead of cast to u64 - add tstamp to tx_flags in GSO, instead of overwrite tx_flags - record skb_shinfo(skb)->tskey for all timestamps, also HW. - optimization in tcp_tx_timestamp: call sock_tx_timestamp only if a tstamp option is set. Signed-off-by: Willem de Bruijn <willemb@google.com> Fixes: 4ed2d765dfac ("net-timestamp: TCP timestamping") Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4ed2d765 |
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04-Aug-2014 |
Willem de Bruijn <willemb@google.com> |
net-timestamp: TCP timestamping TCP timestamping extends SO_TIMESTAMPING to bytestreams. Bytestreams do not have a 1:1 relationship between send() buffers and network packets. The feature interprets a send call on a bytestream as a request for a timestamp for the last byte in that send() buffer. The choice corresponds to a request for a timestamp when all bytes in the buffer have been sent. That assumption depends on in-order kernel transmission. This is the common case. That said, it is possible to construct a traffic shaping tree that would result in reordering. The guarantee is strong, then, but not ironclad. This implementation supports send and sendpages (splice). GSO replaces one large packet with multiple smaller packets. This patch also copies the option into the correct smaller packet. This patch does not yet support timestamping on data in an initial TCP Fast Open SYN, because that takes a very different data path. If ID generation in ee_data is enabled, bytestream timestamps return a byte offset, instead of the packet counter for datagrams. The implementation supports a single timestamp per packet. It silenty replaces requests for previous timestamps. To avoid missing tstamps, flush the tcp queue by disabling Nagle, cork and autocork. Missing tstamps can be detected by offset when the ee_data ID is enabled. Implementation details: - On GSO, the timestamping code can be included in the main loop. I moved it into its own loop to reduce the impact on the common case to a single branch. - To avoid leaking the absolute seqno to userspace, the offset returned in ee_data must always be relative. It is an offset between an skb and sk field. The first is always set (also for GSO & ACK). The second must also never be uninitialized. Only allow the ID option on sockets in the ESTABLISHED state, for which the seqno is available. Never reset it to zero (instead, move it to the current seqno when reenabling the option). Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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5924f17a |
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28-Jun-2014 |
Christoph Paasch <christoph.paasch@uclouvain.be> |
tcp: Fix divide by zero when pushing during tcp-repair When in repair-mode and TCP_RECV_QUEUE is set, we end up calling tcp_push with mss_now being 0. If data is in the send-queue and tcp_set_skb_tso_segs gets called, we crash because it will divide by mss_now: [ 347.151939] divide error: 0000 [#1] SMP [ 347.152907] Modules linked in: [ 347.152907] CPU: 1 PID: 1123 Comm: packetdrill Not tainted 3.16.0-rc2 #4 [ 347.152907] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 [ 347.152907] task: f5b88540 ti: f3c82000 task.ti: f3c82000 [ 347.152907] EIP: 0060:[<c1601359>] EFLAGS: 00210246 CPU: 1 [ 347.152907] EIP is at tcp_set_skb_tso_segs+0x49/0xa0 [ 347.152907] EAX: 00000b67 EBX: f5acd080 ECX: 00000000 EDX: 00000000 [ 347.152907] ESI: f5a28f40 EDI: f3c88f00 EBP: f3c83d10 ESP: f3c83d00 [ 347.152907] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 [ 347.152907] CR0: 80050033 CR2: 083158b0 CR3: 35146000 CR4: 000006b0 [ 347.152907] Stack: [ 347.152907] c167f9d9 f5acd080 000005b4 00000002 f3c83d20 c16013e6 f3c88f00 f5acd080 [ 347.152907] f3c83da0 c1603b5a f3c83d38 c10a0188 00000000 00000000 f3c83d84 c10acc85 [ 347.152907] c1ad5ec0 00000000 00000000 c1ad679c 010003e0 00000000 00000000 f3c88fc8 [ 347.152907] Call Trace: [ 347.152907] [<c167f9d9>] ? apic_timer_interrupt+0x2d/0x34 [ 347.152907] [<c16013e6>] tcp_init_tso_segs+0x36/0x50 [ 347.152907] [<c1603b5a>] tcp_write_xmit+0x7a/0xbf0 [ 347.152907] [<c10a0188>] ? up+0x28/0x40 [ 347.152907] [<c10acc85>] ? console_unlock+0x295/0x480 [ 347.152907] [<c10ad24f>] ? vprintk_emit+0x1ef/0x4b0 [ 347.152907] [<c1605716>] __tcp_push_pending_frames+0x36/0xd0 [ 347.152907] [<c15f4860>] tcp_push+0xf0/0x120 [ 347.152907] [<c15f7641>] tcp_sendmsg+0xf1/0xbf0 [ 347.152907] [<c116d920>] ? kmem_cache_free+0xf0/0x120 [ 347.152907] [<c106a682>] ? __sigqueue_free+0x32/0x40 [ 347.152907] [<c106a682>] ? __sigqueue_free+0x32/0x40 [ 347.152907] [<c114f0f0>] ? do_wp_page+0x3e0/0x850 [ 347.152907] [<c161c36a>] inet_sendmsg+0x4a/0xb0 [ 347.152907] [<c1150269>] ? handle_mm_fault+0x709/0xfb0 [ 347.152907] [<c15a006b>] sock_aio_write+0xbb/0xd0 [ 347.152907] [<c1180b79>] do_sync_write+0x69/0xa0 [ 347.152907] [<c1181023>] vfs_write+0x123/0x160 [ 347.152907] [<c1181d55>] SyS_write+0x55/0xb0 [ 347.152907] [<c167f0d8>] sysenter_do_call+0x12/0x28 This can easily be reproduced with the following packetdrill-script (the "magic" with netem, sk_pacing and limit_output_bytes is done to prevent the kernel from pushing all segments, because hitting the limit without doing this is not so easy with packetdrill): 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 +0 < S 0:0(0) win 32792 <mss 1460> +0 > S. 0:0(0) ack 1 <mss 1460> +0.1 < . 1:1(0) ack 1 win 65000 +0 accept(3, ..., ...) = 4 // This forces that not all segments of the snd-queue will be pushed +0 `tc qdisc add dev tun0 root netem delay 10ms` +0 `sysctl -w net.ipv4.tcp_limit_output_bytes=2` +0 setsockopt(4, SOL_SOCKET, 47, [2], 4) = 0 +0 write(4,...,10000) = 10000 +0 write(4,...,10000) = 10000 // Set tcp-repair stuff, particularly TCP_RECV_QUEUE +0 setsockopt(4, SOL_TCP, 19, [1], 4) = 0 +0 setsockopt(4, SOL_TCP, 20, [1], 4) = 0 // This now will make the write push the remaining segments +0 setsockopt(4, SOL_SOCKET, 47, [20000], 4) = 0 +0 `sysctl -w net.ipv4.tcp_limit_output_bytes=130000` // Now we will crash +0 write(4,...,1000) = 1000 This happens since ec3423257508 (tcp: fix retransmission in repair mode). Prior to that, the call to tcp_push was prevented by a check for tp->repair. The patch fixes it, by adding the new goto-label out_nopush. When exiting tcp_sendmsg and a push is not required, which is the case for tp->repair, we go to this label. When repairing and calling send() with TCP_RECV_QUEUE, the data is actually put in the receive-queue. So, no push is required because no data has been added to the send-queue. Cc: Andrew Vagin <avagin@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Fixes: ec3423257508 (tcp: fix retransmission in repair mode) Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Acked-by: Andrew Vagin <avagin@openvz.org> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1536e285 |
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16-Apr-2014 |
Kenjiro Nakayama <nakayamakenjiro@gmail.com> |
tcp: Add a TCP_FASTOPEN socket option to get a max backlog on its listner This patch adds a TCP_FASTOPEN socket option to get a max backlog on its listener to getsockopt(). Signed-off-by: Kenjiro Nakayama <nakayamakenjiro@gmail.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
740b0f18 |
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26-Feb-2014 |
Eric Dumazet <edumazet@google.com> |
tcp: switch rtt estimations to usec resolution Upcoming congestion controls for TCP require usec resolution for RTT estimations. Millisecond resolution is simply not enough these days. FQ/pacing in DC environments also require this change for finer control and removal of bimodal behavior due to the current hack in tcp_update_pacing_rate() for 'small rtt' TCP_CONG_RTT_STAMP is no longer needed. As Julian Anastasov pointed out, we need to keep user compatibility : tcp_metrics used to export RTT and RTTVAR in msec resolution, so we added RTT_US and RTTVAR_US. An iproute2 patch is needed to use the new attributes if provided by the kernel. In this example ss command displays a srtt of 32 usecs (10Gbit link) lpk51:~# ./ss -i dst lpk52 Netid State Recv-Q Send-Q Local Address:Port Peer Address:Port tcp ESTAB 0 1 10.246.11.51:42959 10.246.11.52:64614 cubic wscale:6,6 rto:201 rtt:0.032/0.001 ato:40 mss:1448 cwnd:10 send 3620.0Mbps pacing_rate 7240.0Mbps unacked:1 rcv_rtt:993 rcv_space:29559 Updated iproute2 ip command displays : lpk51:~# ./ip tcp_metrics | grep 10.246.11.52 10.246.11.52 age 561.914sec cwnd 10 rtt 274us rttvar 213us source 10.246.11.51 Old binary displays : lpk51:~# ip tcp_metrics | grep 10.246.11.52 10.246.11.52 age 561.914sec cwnd 10 rtt 250us rttvar 125us source 10.246.11.51 With help from Julian Anastasov, Stephen Hemminger and Yuchung Cheng Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Yuchung Cheng <ycheng@google.com> Cc: Larry Brakmo <brakmo@google.com> Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f5ddcbbb |
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20-Feb-2014 |
Eric Dumazet <edumazet@google.com> |
net-tcp: fastopen: fix high order allocations This patch fixes two bugs in fastopen : 1) The tcp_sendmsg(..., @size) argument was ignored. Code was relying on user not fooling the kernel with iovec mismatches 2) When MTU is about 64KB, tcp_send_syn_data() attempts order-5 allocations, which are likely to fail when memory gets fragmented. Fixes: 783237e8daf13 ("net-tcp: Fast Open client - sending SYN-data") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Tested-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
977cb0ec |
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13-Feb-2014 |
Eric Dumazet <edumazet@google.com> |
tcp: add pacing_rate information into tcp_info Add two new fields to struct tcp_info, to report sk_pacing_rate and sk_max_pacing_rate to monitoring applications, as ss from iproute2. User exported fields are 64bit, even if kernel is currently using 32bit fields. lpaa5:~# ss -i .. skmem:(r0,rb357120,t0,tb2097152,f1584,w1980880,o0,bl0) ts sack cubic wscale:6,6 rto:400 rtt:0.875/0.75 mss:1448 cwnd:1 ssthresh:12 send 13.2Mbps pacing_rate 3336.2Mbps unacked:15 retrans:1/5448 lost:15 rcv_space:29200 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b10bd54c |
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09-Feb-2014 |
Jesper Juhl <jj@chaosbits.net> |
tcp: correct code comment stating 3 min timeout for FIN_WAIT2, we only do 1 min As far as I can tell we have used a default of 60 seconds for FIN_WAIT2 timeout for ages (since 2.x times??). In any case, the timeout these days is 60 seconds, so the 3 min comment is wrong (and cost me a few minutes of my life when I was debugging a FIN_WAIT2 related problem in a userspace application and checked the kernel source for details). Signed-off-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1774e9f3 |
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19-Nov-2013 |
Peter Zijlstra <peterz@infradead.org> |
sched, net: Clean up preempt_enable_no_resched() abuse The only valid use of preempt_enable_no_resched() is if the very next line is schedule() or if we know preemption cannot actually be enabled by that statement due to known more preempt_count 'refs'. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: rjw@rjwysocki.net Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: rui.zhang@intel.com Cc: jacob.jun.pan@linux.intel.com Cc: Mike Galbraith <bitbucket@online.de> Cc: hpa@zytor.com Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: lenb@kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20131119151338.GF3694@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
996b175e |
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06-Jan-2014 |
Eric Dumazet <edumazet@google.com> |
tcp: out_of_order_queue do not use its lock TCP out_of_order_queue lock is not used, as queue manipulation happens with socket lock held and we therefore use the lockless skb queue routines (as __skb_queue_head()) We can use __skb_queue_head_init() instead of skb_queue_head_init() to make this more consistent. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a181ceb5 |
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17-Dec-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: autocork should not hold first packet in write queue Willem noticed a TCP_RR regression caused by TCP autocorking on a Mellanox test bed. MLX4_EN_TX_COAL_TIME is 16 us, which can be right above RTT between hosts. We can receive a ACK for a packet still in NIC TX ring buffer or in a softnet completion queue. Fix this by always pushing the skb if it is at the head of write queue. Also, as TX completion is lockless, it's safer to perform sk_wmem_alloc test after setting TSQ_THROTTLED. erd:~# MIB="MIN_LATENCY,MEAN_LATENCY,MAX_LATENCY,P99_LATENCY,STDDEV_LATENCY" erd:~# ./netperf -H remote -t TCP_RR -- -o $MIB | tail -n 1 (repeat 3 times) Before patch : 18,1049.87,41004,39631,6295.47 17,239.52,40804,48,2912.79 18,348.40,40877,54,3573.39 After patch : 18,22.84,4606,38,16.39 17,21.56,2871,36,13.51 17,22.46,2705,37,11.83 Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: f54b311142a9 ("tcp: auto corking") Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f54b3111 |
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05-Dec-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: auto corking With the introduction of TCP Small Queues, TSO auto sizing, and TCP pacing, we can implement Automatic Corking in the kernel, to help applications doing small write()/sendmsg() to TCP sockets. Idea is to change tcp_push() to check if the current skb payload is under skb optimal size (a multiple of MSS bytes) If under 'size_goal', and at least one packet is still in Qdisc or NIC TX queues, set the TCP Small Queue Throttled bit, so that the push will be delayed up to TX completion time. This delay might allow the application to coalesce more bytes in the skb in following write()/sendmsg()/sendfile() system calls. The exact duration of the delay is depending on the dynamics of the system, and might be zero if no packet for this flow is actually held in Qdisc or NIC TX ring. Using FQ/pacing is a way to increase the probability of autocorking being triggered. Add a new sysctl (/proc/sys/net/ipv4/tcp_autocorking) to control this feature and default it to 1 (enabled) Add a new SNMP counter : nstat -a | grep TcpExtTCPAutoCorking This counter is incremented every time we detected skb was under used and its flush was deferred. Tested: Interesting effects when using line buffered commands under ssh. Excellent performance results in term of cpu usage and total throughput. lpq83:~# echo 1 >/proc/sys/net/ipv4/tcp_autocorking lpq83:~# perf stat ./super_netperf 4 -t TCP_STREAM -H lpq84 -- -m 128 9410.39 Performance counter stats for './super_netperf 4 -t TCP_STREAM -H lpq84 -- -m 128': 35209.439626 task-clock # 2.901 CPUs utilized 2,294 context-switches # 0.065 K/sec 101 CPU-migrations # 0.003 K/sec 4,079 page-faults # 0.116 K/sec 97,923,241,298 cycles # 2.781 GHz [83.31%] 51,832,908,236 stalled-cycles-frontend # 52.93% frontend cycles idle [83.30%] 25,697,986,603 stalled-cycles-backend # 26.24% backend cycles idle [66.70%] 102,225,978,536 instructions # 1.04 insns per cycle # 0.51 stalled cycles per insn [83.38%] 18,657,696,819 branches # 529.906 M/sec [83.29%] 91,679,646 branch-misses # 0.49% of all branches [83.40%] 12.136204899 seconds time elapsed lpq83:~# echo 0 >/proc/sys/net/ipv4/tcp_autocorking lpq83:~# perf stat ./super_netperf 4 -t TCP_STREAM -H lpq84 -- -m 128 6624.89 Performance counter stats for './super_netperf 4 -t TCP_STREAM -H lpq84 -- -m 128': 40045.864494 task-clock # 3.301 CPUs utilized 171 context-switches # 0.004 K/sec 53 CPU-migrations # 0.001 K/sec 4,080 page-faults # 0.102 K/sec 111,340,458,645 cycles # 2.780 GHz [83.34%] 61,778,039,277 stalled-cycles-frontend # 55.49% frontend cycles idle [83.31%] 29,295,522,759 stalled-cycles-backend # 26.31% backend cycles idle [66.67%] 108,654,349,355 instructions # 0.98 insns per cycle # 0.57 stalled cycles per insn [83.34%] 19,552,170,748 branches # 488.244 M/sec [83.34%] 157,875,417 branch-misses # 0.81% of all branches [83.34%] 12.130267788 seconds time elapsed Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
98e09386 |
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13-Nov-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: tsq: restore minimal amount of queueing After commit c9eeec26e32e ("tcp: TSQ can use a dynamic limit"), several users reported throughput regressions, notably on mvneta and wifi adapters. 802.11 AMPDU requires a fair amount of queueing to be effective. This patch partially reverts the change done in tcp_write_xmit() so that the minimal amount is sysctl_tcp_limit_output_bytes. It also remove the use of this sysctl while building skb stored in write queue, as TSO autosizing does the right thing anyway. Users with well behaving NICS and correct qdisc (like sch_fq), can then lower the default sysctl_tcp_limit_output_bytes value from 128KB to 8KB. This new usage of sysctl_tcp_limit_output_bytes permits each driver authors to check how their driver performs when/if the value is set to a minimum of 4KB. Normally, line rate for a single TCP flow should be possible, but some drivers rely on timers to perform TX completion and too long TX completion delays prevent reaching full throughput. Fixes: c9eeec26e32e ("tcp: TSQ can use a dynamic limit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Sujith Manoharan <sujith@msujith.org> Reported-by: Arnaud Ebalard <arno@natisbad.org> Tested-by: Sujith Manoharan <sujith@msujith.org> Cc: Felix Fietkau <nbd@openwrt.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
27bf6970 |
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16-Oct-2013 |
Vinod Koul <vkoul@kernel.org> |
net: use DMA_COMPLETE for dma completion status Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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#
a4fe34bf |
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19-Oct-2013 |
Eric W. Biederman <ebiederm@xmission.com> |
tcp_memcontrol: Remove the per netns control. The code that is implemented is per memory cgroup not per netns, and having per netns bits is just confusing. Remove the per netns bits to make it easier to see what is really going on. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
05dbc7b5 |
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03-Oct-2013 |
Eric Dumazet <edumazet@google.com> |
tcp/dccp: remove twchain TCP listener refactoring, part 3 : Our goal is to hash SYN_RECV sockets into main ehash for fast lookup, and parallel SYN processing. Current inet_ehash_bucket contains two chains, one for ESTABLISH (and friend states) sockets, another for TIME_WAIT sockets only. As the hash table is sized to get at most one socket per bucket, it makes little sense to have separate twchain, as it makes the lookup slightly more complicated, and doubles hash table memory usage. If we make sure all socket types have the lookup keys at the same offsets, we can use a generic and faster lookup. It turns out TIME_WAIT and ESTABLISHED sockets already have common lookup fields for IPv4. [ INET_TW_MATCH() is no longer needed ] I'll provide a follow-up to factorize IPv6 lookup as well, to remove INET6_TW_MATCH() This way, SYN_RECV pseudo sockets will be supported the same. A new sock_gen_put() helper is added, doing either a sock_put() or inet_twsk_put() [ and will support SYN_RECV later ]. Note this helper should only be called in real slow path, when rcu lookup found a socket that was moved to another identity (freed/reused immediately), but could eventually be used in other contexts, like sock_edemux() Before patch : dmesg | grep "TCP established" TCP established hash table entries: 524288 (order: 11, 8388608 bytes) After patch : TCP established hash table entries: 524288 (order: 10, 4194304 bytes) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e2e5c4c0 |
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05-Sep-2013 |
Dave Jones <davej@redhat.com> |
tcp: Add missing braces to do_tcp_setsockopt Signed-off-by: Dave Jones <davej@fedoraproject.org> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
95bd09eb |
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27-Aug-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: TSO packets automatic sizing After hearing many people over past years complaining against TSO being bursty or even buggy, we are proud to present automatic sizing of TSO packets. One part of the problem is that tcp_tso_should_defer() uses an heuristic relying on upcoming ACKS instead of a timer, but more generally, having big TSO packets makes little sense for low rates, as it tends to create micro bursts on the network, and general consensus is to reduce the buffering amount. This patch introduces a per socket sk_pacing_rate, that approximates the current sending rate, and allows us to size the TSO packets so that we try to send one packet every ms. This field could be set by other transports. Patch has no impact for high speed flows, where having large TSO packets makes sense to reach line rate. For other flows, this helps better packet scheduling and ACK clocking. This patch increases performance of TCP flows in lossy environments. A new sysctl (tcp_min_tso_segs) is added, to specify the minimal size of a TSO packet (default being 2). A follow-up patch will provide a new packet scheduler (FQ), using sk_pacing_rate as an input to perform optional per flow pacing. This explains why we chose to set sk_pacing_rate to twice the current rate, allowing 'slow start' ramp up. sk_pacing_rate = 2 * cwnd * mss / srtt v2: Neal Cardwell reported a suspect deferring of last two segments on initial write of 10 MSS, I had to change tcp_tso_should_defer() to take into account tp->xmit_size_goal_segs Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Van Jacobson <vanj@google.com> Cc: Tom Herbert <therbert@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7ed5c5ae |
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16-Aug-2013 |
Andrey Vagin <avagin@openvz.org> |
tcp: set timestamps for restored skb-s When the repair mode is turned off, the write queue seqs are updated so that the whole queue is considered to be 'already sent. The "when" field must be set for such skb. It's used in tcp_rearm_rto for example. If the "when" field isn't set, the retransmit timeout can be calculated incorrectly and a tcp connected can stop for two minutes (TCP_RTO_MAX). Acked-by: Pavel Emelyanov <xemul@parallels.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c0155b2d |
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31-Jul-2013 |
Dmitry Popov <dp@highloadlab.com> |
tcp: Remove unused tcpct declarations and comments Remove declaration, 4 defines and confusing comment that are no longer used since 1a2c6181c4 ("tcp: Remove TCPCT"). Signed-off-by: Dmitry Popov <dp@highloadlab.com> Acked-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c9bee3b7 |
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22-Jul-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: TCP_NOTSENT_LOWAT socket option Idea of this patch is to add optional limitation of number of unsent bytes in TCP sockets, to reduce usage of kernel memory. TCP receiver might announce a big window, and TCP sender autotuning might allow a large amount of bytes in write queue, but this has little performance impact if a large part of this buffering is wasted : Write queue needs to be large only to deal with large BDP, not necessarily to cope with scheduling delays (incoming ACKS make room for the application to queue more bytes) For most workloads, using a value of 128 KB or less is OK to give applications enough time to react to POLLOUT events in time (or being awaken in a blocking sendmsg()) This patch adds two ways to set the limit : 1) Per socket option TCP_NOTSENT_LOWAT 2) A sysctl (/proc/sys/net/ipv4/tcp_notsent_lowat) for sockets not using TCP_NOTSENT_LOWAT socket option (or setting a zero value) Default value being UINT_MAX (0xFFFFFFFF), meaning this has no effect. This changes poll()/select()/epoll() to report POLLOUT only if number of unsent bytes is below tp->nosent_lowat Note this might increase number of sendmsg()/sendfile() calls when using non blocking sockets, and increase number of context switches for blocking sockets. Note this is not related to SO_SNDLOWAT (as SO_SNDLOWAT is defined as : Specify the minimum number of bytes in the buffer until the socket layer will pass the data to the protocol) Tested: netperf sessions, and watching /proc/net/protocols "memory" column for TCP With 200 concurrent netperf -t TCP_STREAM sessions, amount of kernel memory used by TCP buffers shrinks by ~55 % (20567 pages instead of 45458) lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols TCPv6 1880 2 45458 no 208 yes ipv6 y y y y y y y y y y y y y n y y y y y TCP 1696 508 45458 no 208 yes kernel y y y y y y y y y y y y y n y y y y y lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols TCPv6 1880 2 20567 no 208 yes ipv6 y y y y y y y y y y y y y n y y y y y TCP 1696 508 20567 no 208 yes kernel y y y y y y y y y y y y y n y y y y y Using 128KB has no bad effect on the throughput or cpu usage of a single flow, although there is an increase of context switches. A bonus is that we hold socket lock for a shorter amount of time and should improve latencies of ACK processing. lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3 OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf. Local Remote Local Elapsed Throughput Throughput Local Local Remote Remote Local Remote Service Send Socket Recv Socket Send Time Units CPU CPU CPU CPU Service Service Demand Size Size Size (sec) Util Util Util Util Demand Demand Units Final Final % Method % Method 1651584 6291456 16384 20.00 17447.90 10^6bits/s 3.13 S -1.00 U 0.353 -1.000 usec/KB Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3': 412,514 context-switches 200.034645535 seconds time elapsed lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3 OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf. Local Remote Local Elapsed Throughput Throughput Local Local Remote Remote Local Remote Service Send Socket Recv Socket Send Time Units CPU CPU CPU CPU Service Service Demand Size Size Size (sec) Util Util Util Util Demand Demand Units Final Final % Method % Method 1593240 6291456 16384 20.00 17321.16 10^6bits/s 3.35 S -1.00 U 0.381 -1.000 usec/KB Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3': 2,675,818 context-switches 200.029651391 seconds time elapsed Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-By: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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64dc6130 |
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22-Jul-2013 |
Eric Dumazet <edumazet@google.com> |
net: add sk_stream_is_writeable() helper Several call sites use the hardcoded following condition : sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) Lets use a helper because TCP_NOTSENT_LOWAT support will change this condition for TCP sockets. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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076bb0c8 |
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10-Jul-2013 |
Eliezer Tamir <eliezer.tamir@linux.intel.com> |
net: rename include/net/ll_poll.h to include/net/busy_poll.h Rename the file and correct all the places where it is included. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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cbf55001 |
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08-Jul-2013 |
Eliezer Tamir <eliezer.tamir@linux.intel.com> |
net: rename low latency sockets functions to busy poll Rename functions in include/net/ll_poll.h to busy wait. Clarify documentation about expected power use increase. Rename POLL_LL to POLL_BUSY_LOOP. Add need_resched() testing to poll/select busy loops. Note, that in select and poll can_busy_poll is dynamic and is updated continuously to reflect the existence of supported sockets with valid queue information. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d30e383b |
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10-Jun-2013 |
Eliezer Tamir <eliezer.tamir@linux.intel.com> |
tcp: add low latency socket poll support. Adds low latency socket poll support for TCP. In tcp_v[46]_rcv() add a call to sk_mark_ll() to copy the napi_id from the skb to the sk. In tcp_recvmsg(), when there is no data in the socket we busy-poll. This is a good example of how to add busy-poll support to more protocols. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Tested-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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28850dc7 |
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06-Jun-2013 |
Daniel Borkmann <daniel@iogearbox.net> |
net: tcp: move GRO/GSO functions to tcp_offload Would be good to make things explicit and move those functions to a new file called tcp_offload.c, thus make this similar to tcpv6_offload.c. While moving all related functions into tcp_offload.c, we can also make some of them static, since they are only used there. Also, add an explicit registration function. Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5ee98591 |
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06-Jun-2013 |
Daniel Borkmann <daniel@iogearbox.net> |
net: minor: tcp: use tcp_skb_mss helper in tcp_tso_segment We have the minimal inline helper tcp_skb_mss to access skb_shinfo(skb)->gso_size, so also use it here to get mss. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c3f1dbaf |
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31-May-2013 |
David Majnemer <majnemer@google.com> |
net: Update RFS target at poll for tcp/udp The current state of affairs is that read()/write() will setup RFS (Receive Flow Steering) for internet protocol sockets while poll()/epoll() does not. When poll() gets called with a TCP or UDP socket, we should update the flow target. This permits to RFS (if enabled) to select the appropriate CPU for following incoming packets. Note: Only connected UDP sockets can benefit from RFS. Signed-off-by: David Majnemer <majnemer@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Paul Turner <pjt@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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f7c0c2ae |
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28-May-2013 |
Simon Horman <horms@verge.net.au> |
ipv4: Correct comparisons and calculations using skb->tail and skb-transport_header This corrects an regression introduced by "net: Use 16bits for *_headers fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In that case skb->tail will be a pointer whereas skb->transport_header will be an offset from head. This is corrected by using wrappers that ensure that comparisons and calculations are always made using pointers. Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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0d89d203 |
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23-May-2013 |
Simon Horman <horms@verge.net.au> |
MPLS: Add limited GSO support In the case where a non-MPLS packet is received and an MPLS stack is added it may well be the case that the original skb is GSO but the NIC used for transmit does not support GSO of MPLS packets. The aim of this code is to provide GSO in software for MPLS packets whose skbs are GSO. SKB Usage: When an implementation adds an MPLS stack to a non-MPLS packet it should do the following to skb metadata: * Set skb->inner_protocol to the old non-MPLS ethertype of the packet. skb->inner_protocol is added by this patch. * Set skb->protocol to the new MPLS ethertype of the packet. * Set skb->network_header to correspond to the end of the L3 header, including the MPLS label stack. I have posted a patch, "[PATCH v3.29] datapath: Add basic MPLS support to kernel" which adds MPLS support to the kernel datapath of Open vSwtich. That patch sets the above requirements in datapath/actions.c:push_mpls() and was used to exercise this code. The datapath patch is against the Open vSwtich tree but it is intended that it be added to the Open vSwtich code present in the mainline Linux kernel at some point. Features: I believe that the approach that I have taken is at least partially consistent with the handling of other protocols. Jesse, I understand that you have some ideas here. I am more than happy to change my implementation. This patch adds dev->mpls_features which may be used by devices to advertise features supported for MPLS packets. A new NETIF_F_MPLS_GSO feature is added for devices which support hardware MPLS GSO offload. Currently no devices support this and MPLS GSO always falls back to software. Alternate Implementation: One possible alternate implementation is to teach netif_skb_features() and skb_network_protocol() about MPLS, in a similar way to their understanding of VLANs. I believe this would avoid the need for net/mpls/mpls_gso.c and in particular the calls to __skb_push() and __skb_push() in mpls_gso_segment(). I have decided on the implementation in this patch as it should not introduce any overhead in the case where mpls_gso is not compiled into the kernel or inserted as a module. MPLS GSO suggested by Jesse Gross. Based in part on "v4 GRE: Add TCP segmentation offload for GRE" by Pravin B Shelar. Cc: Jesse Gross <jesse@nicira.com> Cc: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
71cea17e |
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20-May-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: md5: remove spinlock usage in fast path TCP md5 code uses per cpu variables but protects access to them with a shared spinlock, which is a contention point. [ tcp_md5sig_pool_lock is locked twice per incoming packet ] Makes things much simpler, by allocating crypto structures once, first time a socket needs md5 keys, and not deallocating them as they are really small. Next step would be to allow crypto allocations being done in a NUMA aware way. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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6ff50cd5 |
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15-May-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: gso: do not generate out of order packets GSO TCP handler has following issues : 1) ooo_okay from original GSO packet is duplicated to all segments 2) segments (but the last one) are orphaned, so transmit path can not get transmit queue number from the socket. This happens if GSO segmentation is done before stacked device for example. Result is we can send packets from a given TCP flow to different TX queues (if using multiqueue NICS). This generates OOO problems and spurious SACK & retransmits. Fix this by keeping socket pointer set for all segments. This means that every segment must also have a destructor, and the original gso skb truesize must be split on all segments, to keep precise sk->sk_wmem_alloc accounting. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Maciej Żenczykowski <maze@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
54d27fcb |
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13-May-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: fix tcp_md5_hash_skb_data() TCP md5 communications fail [1] for some devices, because sg/crypto code assume page offsets are below PAGE_SIZE. This was discovered using mlx4 driver [2], but I suspect loopback might trigger the same bug now we use order-3 pages in tcp_sendmsg() [1] Failure is giving following messages. huh, entered softirq 3 NET_RX ffffffff806ad230 preempt_count 00000100, exited with 00000101? [2] mlx4 driver uses order-2 pages to allocate RX frags Reported-by: Matt Schnall <mischnal@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Bernhard Beck <bbeck@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bece1b97 |
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12-Apr-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: tcp_tso_segment() small optimization We can move th->check computation out of the loop, as compiler doesn't know each skb initially share same tcp headers after skb_segment() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d6a4a104 |
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12-Apr-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: GSO should be TSQ friendly I noticed that TSQ (TCP Small queues) was less effective when TSO is turned off, and GSO is on. If BQL is not enabled, TSQ has then no effect. It turns out the GSO engine frees the original gso_skb at the time the fragments are generated and queued to the NIC. We should instead call the tcp_wfree() destructor for the last fragment, to keep the flow control as intended in TSQ. This effectively limits the number of queued packets on qdisc + NIC layers. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Nandita Dukkipati <nanditad@google.com> Cc: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1a2c6181 |
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17-Mar-2013 |
Christoph Paasch <christoph.paasch@uclouvain.be> |
tcp: Remove TCPCT TCPCT uses option-number 253, reserved for experimental use and should not be used in production environments. Further, TCPCT does not fully implement RFC 6013. As a nice side-effect, removing TCPCT increases TCP's performance for very short flows: Doing an apache-benchmark with -c 100 -n 100000, sending HTTP-requests for files of 1KB size. before this patch: average (among 7 runs) of 20845.5 Requests/Second after: average (among 7 runs) of 21403.6 Requests/Second Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
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16fad69c |
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13-Mar-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: fix skb_availroom() Chrome OS team reported a crash on a Pixel ChromeBook in TCP stack : https://code.google.com/p/chromium/issues/detail?id=182056 commit a21d45726acac (tcp: avoid order-1 allocations on wifi and tx path) did a poor choice adding an 'avail_size' field to skb, while what we really needed was a 'reserved_tailroom' one. It would have avoided commit 22b4a4f22da (tcp: fix retransmit of partially acked frames) and this commit. Crash occurs because skb_split() is not aware of the 'avail_size' management (and should not be aware) Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Mukesh Agrawal <quiche@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
73136267 |
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07-Mar-2013 |
Pravin B Shelar <pshelar@nicira.com> |
tunneling: Add generic Tunnel segmentation. Adds generic tunneling offloading support for IPv4-UDP based tunnels. GSO type is added to request this offload for a skb. netdev feature NETIF_F_UDP_TUNNEL is added for hardware offloaded udp-tunnel support. Currently no device supports this feature, software offload is used. This can be used by tunneling protocols like VXLAN. CC: Jesse Gross <jesse@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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68c33163 |
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14-Feb-2013 |
Pravin B Shelar <pshelar@nicira.com> |
v4 GRE: Add TCP segmentation offload for GRE Following patch adds GRE protocol offload handler so that skb_gso_segment() can segment GRE packets. SKB GSO CB is added to keep track of total header length so that skb_segment can push entire header. e.g. in case of GRE, skb_segment need to push inner and outer headers to every segment. New NETIF_F_GRE_GSO feature is added for devices which support HW GRE TSO offload. Currently none of devices support it therefore GRE GSO always fall backs to software GSO. [ Compute pkt_len before ip_local_out() invocation. -DaveM ] Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c9af6db4 |
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11-Feb-2013 |
Pravin B Shelar <pshelar@nicira.com> |
net: Fix possible wrong checksum generation. Patch cef401de7be8c4e (net: fix possible wrong checksum generation) fixed wrong checksum calculation but it broke TSO by defining new GSO type but not a netdev feature for that type. net_gso_ok() would not allow hardware checksum/segmentation offload of such packets without the feature. Following patch fixes TSO and wrong checksum. This patch uses same logic that Eric Dumazet used. Patch introduces new flag SKBTX_SHARED_FRAG if at least one frag can be modified by the user. but SKBTX_SHARED_FRAG flag is kept in skb shared info tx_flags rather than gso_type. tx_flags is better compared to gso_type since we can have skb with shared frag without gso packet. It does not link SHARED_FRAG to GSO, So there is no need to define netdev feature for this. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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93be6ce0 |
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10-Feb-2013 |
Andrey Vagin <avagin@openvz.org> |
tcp: set and get per-socket timestamp A timestamp can be set, only if a socket is in the repair mode. This patch adds a new socket option TCP_TIMESTAMP, which allows to get and set current tcp times stamp. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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ceaa1fef |
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10-Feb-2013 |
Andrey Vagin <avagin@openvz.org> |
tcp: adding a per-socket timestamp offset This functionality is used for restoring tcp sockets. A tcp timestamp depends on how long a system has been running, so it's differ for each host. The solution is to set a per-socket offset. A per-socket offset for a TIME_WAIT socket is inherited from a proper tcp socket. tcp_request_sock doesn't have a timestamp offset, because the repair mode for them are not implemented. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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ca2eb567 |
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05-Feb-2013 |
Stephen Hemminger <stephen@networkplumber.org> |
tcp: remove Appropriate Byte Count support TCP Appropriate Byte Count was added by me, but later disabled. There is no point in maintaining it since it is a potential source of bugs and Linux already implements other better window protection heuristics. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cef401de |
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25-Jan-2013 |
Eric Dumazet <edumazet@google.com> |
net: fix possible wrong checksum generation Pravin Shelar mentioned that GSO could potentially generate wrong TX checksum if skb has fragments that are overwritten by the user between the checksum computation and transmit. He suggested to linearize skbs but this extra copy can be avoided for normal tcp skbs cooked by tcp_sendmsg(). This patch introduces a new SKB_GSO_SHARED_FRAG flag, set in skb_shinfo(skb)->gso_type if at least one frag can be modified by the user. Typical sources of such possible overwrites are {vm}splice(), sendfile(), and macvtap/tun/virtio_net drivers. Tested: $ netperf -H 7.7.8.84 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 3959.52 $ netperf -H 7.7.8.84 -t TCP_SENDFILE TCP SENDFILE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 3216.80 Performance of the SENDFILE is impacted by the extra allocation and copy, and because we use order-0 pages, while the TCP_STREAM uses bigger pages. Reported-by: Pravin Shelar <pshelar@nicira.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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50c3a487 |
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21-Jan-2013 |
YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@linux-ipv6.org> |
ipv4: Use IS_ERR_OR_NULL(). Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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f26845b4 |
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09-Jan-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: fix splice() and tcp collapsing interaction Under unusual circumstances, TCP collapse can split a big GRO TCP packet while its being used in a splice(socket->pipe) operation. skb_splice_bits() releases the socket lock before calling splice_to_pipe(). [ 1081.353685] WARNING: at net/ipv4/tcp.c:1330 tcp_cleanup_rbuf+0x4d/0xfc() [ 1081.371956] Hardware name: System x3690 X5 -[7148Z68]- [ 1081.391820] cleanup rbuf bug: copied AD3BCF1 seq AD370AF rcvnxt AD3CF13 To fix this problem, we must eat skbs in tcp_recv_skb(). Remove the inline keyword from tcp_recv_skb() definition since it has three call sites. Reported-by: Christian Becker <c.becker@traviangames.com> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
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ff905b1e |
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10-Jan-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: splice: fix an infinite loop in tcp_read_sock() commit 02275a2ee7c0 (tcp: don't abort splice() after small transfers) added a regression. [ 83.843570] INFO: rcu_sched self-detected stall on CPU [ 83.844575] INFO: rcu_sched detected stalls on CPUs/tasks: { 6} (detected by 0, t=21002 jiffies, g=4457, c=4456, q=13132) [ 83.844582] Task dump for CPU 6: [ 83.844584] netperf R running task 0 8966 8952 0x0000000c [ 83.844587] 0000000000000000 0000000000000006 0000000000006c6c 0000000000000000 [ 83.844589] 000000000000006c 0000000000000096 ffffffff819ce2bc ffffffffffffff10 [ 83.844592] ffffffff81088679 0000000000000010 0000000000000246 ffff880c4b9ddcd8 [ 83.844594] Call Trace: [ 83.844596] [<ffffffff81088679>] ? vprintk_emit+0x1c9/0x4c0 [ 83.844601] [<ffffffff815ad449>] ? schedule+0x29/0x70 [ 83.844606] [<ffffffff81537bd2>] ? tcp_splice_data_recv+0x42/0x50 [ 83.844610] [<ffffffff8153beaa>] ? tcp_read_sock+0xda/0x260 [ 83.844613] [<ffffffff81537b90>] ? tcp_prequeue_process+0xb0/0xb0 [ 83.844615] [<ffffffff8153c0f0>] ? tcp_splice_read+0xc0/0x250 [ 83.844618] [<ffffffff814dc0c2>] ? sock_splice_read+0x22/0x30 [ 83.844622] [<ffffffff811b820b>] ? do_splice_to+0x7b/0xa0 [ 83.844627] [<ffffffff811ba4bc>] ? sys_splice+0x59c/0x5d0 [ 83.844630] [<ffffffff8119745b>] ? putname+0x2b/0x40 [ 83.844633] [<ffffffff8118bcb4>] ? do_sys_open+0x174/0x1e0 [ 83.844636] [<ffffffff815b6202>] ? system_call_fastpath+0x16/0x1b if recv_actor() returns 0, we should stop immediately, because looping wont give a chance to drain the pipe. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e239345f |
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08-Nov-2012 |
Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> |
dmaengine: remove dma_async_memcpy_complete() macro Just use dma_async_is_tx_complete() directly. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <djbw@fb.com>
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#
b9ee8683 |
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08-Nov-2012 |
Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> |
dmaengine: remove dma_async_memcpy_pending() macro Just use dma_async_issue_pending() directly. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <djbw@fb.com>
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#
02275a2e |
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02-Dec-2012 |
Willy Tarreau <w@1wt.eu> |
tcp: don't abort splice() after small transfers TCP coalescing added a regression in splice(socket->pipe) performance, for some workloads because of the way tcp_read_sock() is implemented. The reason for this is the break when (offset + 1 != skb->len). As we released the socket lock, this condition is possible if TCP stack added a fragment to the skb, which can happen with TCP coalescing. So let's go back to the beginning of the loop when this happens, to give a chance to splice more frags per system call. Doing so fixes the issue and makes GRO 10% faster than LRO on CPU-bound splice() workloads instead of the opposite. Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
64022d0b |
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01-Dec-2012 |
Eric Dumazet <edumazet@google.com> |
tcp: fix crashes in do_tcp_sendpages() Recent network changes allowed high order pages being used for skb fragments. This uncovered a bug in do_tcp_sendpages() which was assuming its caller provided an array of order-0 page pointers. We only have to deal with a single page in this function, and its order is irrelevant. Reported-by: Willy Tarreau <w@1wt.eu> Tested-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fd90b29d |
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30-Nov-2012 |
Eric Dumazet <edumazet@google.com> |
tcp: change default tcp hash size As time passed, available memory increased faster than number of concurrent tcp sockets. As a result, a machine with 4GB of ram gets a hash table with 524288 slots, using 8388608 bytes of memory. Lets change that by a 16x factor (one slot for 128 KB of ram) Even if a small machine needs a _lot_ of sockets, tcp lookups are now very efficient, using one cache line per socket. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
52e804c6 |
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15-Nov-2012 |
Eric W. Biederman <ebiederm@xmission.com> |
net: Allow userns root to control ipv4 Allow an unpriviled user who has created a user namespace, and then created a network namespace to effectively use the new network namespace, by reducing capable(CAP_NET_ADMIN) and capable(CAP_NET_RAW) calls to be ns_capable(net->user_ns, CAP_NET_ADMIN), or capable(net->user_ns, CAP_NET_RAW) calls. Settings that merely control a single network device are allowed. Either the network device is a logical network device where restrictions make no difference or the network device is hardware NIC that has been explicity moved from the initial network namespace. In general policy and network stack state changes are allowed while resource control is left unchanged. Allow creating raw sockets. Allow the SIOCSARP ioctl to control the arp cache. Allow the SIOCSIFFLAG ioctl to allow setting network device flags. Allow the SIOCSIFADDR ioctl to allow setting a netdevice ipv4 address. Allow the SIOCSIFBRDADDR ioctl to allow setting a netdevice ipv4 broadcast address. Allow the SIOCSIFDSTADDR ioctl to allow setting a netdevice ipv4 destination address. Allow the SIOCSIFNETMASK ioctl to allow setting a netdevice ipv4 netmask. Allow the SIOCADDRT and SIOCDELRT ioctls to allow adding and deleting ipv4 routes. Allow the SIOCADDTUNNEL, SIOCCHGTUNNEL and SIOCDELTUNNEL ioctls for adding, changing and deleting gre tunnels. Allow the SIOCADDTUNNEL, SIOCCHGTUNNEL and SIOCDELTUNNEL ioctls for adding, changing and deleting ipip tunnels. Allow the SIOCADDTUNNEL, SIOCCHGTUNNEL and SIOCDELTUNNEL ioctls for adding, changing and deleting ipsec virtual tunnel interfaces. Allow setting the MRT_INIT, MRT_DONE, MRT_ADD_VIF, MRT_DEL_VIF, MRT_ADD_MFC, MRT_DEL_MFC, MRT_ASSERT, MRT_PIM, MRT_TABLE socket options on multicast routing sockets. Allow setting and receiving IPOPT_CIPSO, IP_OPT_SEC, IP_OPT_SID and arbitrary ip options. Allow setting IP_SEC_POLICY/IP_XFRM_POLICY ipv4 socket option. Allow setting the IP_TRANSPARENT ipv4 socket option. Allow setting the TCP_REPAIR socket option. Allow setting the TCP_CONGESTION socket option. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ec342325 |
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14-Nov-2012 |
Andrew Vagin <avagin@openvz.org> |
tcp: fix retransmission in repair mode Currently if a socket was repaired with a few packet in a write queue, a kernel bug may be triggered: kernel BUG at net/ipv4/tcp_output.c:2330! RIP: 0010:[<ffffffff8155784f>] tcp_retransmit_skb+0x5ff/0x610 According to the initial realization v3.4-rc2-963-gc0e88ff, all skb-s should look like already posted. This patch fixes code according with this sentence. Here are three points, which were not done in the initial patch: 1. A tcp send head should not be changed 2. Initialize TSO state of a skb 3. Reset the retransmission time This patch moves logic from tcp_sendmsg to tcp_write_xmit. A packet passes the ussual way, but isn't sent to network. This patch solves all described problems and handles tcp_sendpages. Cc: Pavel Emelyanov <xemul@parallels.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Andrey Vagin <avagin@openvz.org> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6f73601e |
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19-Oct-2012 |
Yuchung Cheng <ycheng@google.com> |
tcp: add SYN/data info to TCP_INFO Add a bit TCPI_OPT_SYN_DATA (32) to the socket option TCP_INFO:tcpi_options. It's set if the data in SYN (sent or received) is acked by SYN-ACK. Server or client application can use this information to check Fast Open success rate. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0e71c55c |
|
21-Oct-2012 |
Eric Dumazet <edumazet@google.com> |
tcp: speedup SIOCINQ ioctl SIOCINQ can use the lock_sock_fast() version to avoid double acquisition of socket lock. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a3374c42 |
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18-Oct-2012 |
Eric Dumazet <edumazet@google.com> |
tcp: fix FIONREAD/SIOCINQ tcp_ioctl() tries to take into account if tcp socket received a FIN to report correct number bytes in receive queue. But its flaky because if the application ate the last skb, we return 1 instead of 0. Correct way to detect that FIN was received is to test SOCK_DONE. Reported-by: Elliot Hughes <enh@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5640f768 |
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23-Sep-2012 |
Eric Dumazet <edumazet@google.com> |
net: use a per task frag allocator We currently use a per socket order-0 page cache for tcp_sendmsg() operations. This page is used to build fragments for skbs. Its done to increase probability of coalescing small write() into single segments in skbs still in write queue (not yet sent) But it wastes a lot of memory for applications handling many mostly idle sockets, since each socket holds one page in sk->sk_sndmsg_page Its also quite inefficient to build TSO 64KB packets, because we need about 16 pages per skb on arches where PAGE_SIZE = 4096, so we hit page allocator more than wanted. This patch adds a per task frag allocator and uses bigger pages, if available. An automatic fallback is done in case of memory pressure. (up to 32768 bytes per frag, thats order-3 pages on x86) This increases TCP stream performance by 20% on loopback device, but also benefits on other network devices, since 8x less frags are mapped on transmit and unmapped on tx completion. Alexander Duyck mentioned a probable performance win on systems with IOMMU enabled. Its possible some SG enabled hardware cant cope with bigger fragments, but their ndo_start_xmit() should already handle this, splitting a fragment in sub fragments, since some arches have PAGE_SIZE=65536 Successfully tested on various ethernet devices. (ixgbe, igb, bnx2x, tg3, mellanox mlx4) Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Cc: Vijay Subramanian <subramanian.vijay@gmail.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bc26ccd8 |
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19-Sep-2012 |
Andrey Vagin <avagin@openvz.org> |
tcp: restore rcv_wscale in a repair mode (v2) rcv_wscale is a symetric parameter with snd_wscale. Both this parameters are set on a connection handshake. Without this value a remote window size can not be interpreted correctly, because a value from a packet should be shifted on rcv_wscale. And one more thing is that wscale_ok should be set too. This patch doesn't break a backward compatibility. If someone uses it in a old scheme, a rcv window will be restored with the same bug (rcv_wscale = 0). v2: Save backward compatibility on big-endian system. Before the first two bytes were snd_wscale and the second two bytes were rcv_wscale. Now snd_wscale is opt_val & 0xFFFF and rcv_wscale >> 16. This approach is independent on byte ordering. Cc: David S. Miller <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> CC: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrew Vagin <avagin@openvz.org> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bb68b647 |
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18-Sep-2012 |
Christoph Paasch <christoph.paasch@uclouvain.be> |
ipv4: Don't add TCP-code in inet_sock_destruct Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Acked-by: H.K. Jerry Chu <hkchu@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
15c04175 |
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13-Sep-2012 |
Michal Kubeček <mkubecek@suse.cz> |
tcp: flush DMA queue before sk_wait_data if rcv_wnd is zero If recv() syscall is called for a TCP socket so that - IOAT DMA is used - MSG_WAITALL flag is used - requested length is bigger than sk_rcvbuf - enough data has already arrived to bring rcv_wnd to zero then when tcp_recvmsg() gets to calling sk_wait_data(), receive window can be still zero while sk_async_wait_queue exhausts enough space to keep it zero. As this queue isn't cleaned until the tcp_service_net_dma() call, sk_wait_data() cannot receive any data and blocks forever. If zero receive window and non-empty sk_async_wait_queue is detected before calling sk_wait_data(), process the queue first. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8336886f |
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30-Aug-2012 |
Jerry Chu <hkchu@google.com> |
tcp: TCP Fast Open Server - support TFO listeners This patch builds on top of the previous patch to add the support for TFO listeners. This includes - 1. allocating, properly initializing, and managing the per listener fastopen_queue structure when TFO is enabled 2. changes to the inet_csk_accept code to support TFO. E.g., the request_sock can no longer be freed upon accept(), not until 3WHS finishes 3. allowing a TCP_SYN_RECV socket to properly poll() and sendmsg() if it's a TFO socket 4. properly closing a TFO listener, and a TFO socket before 3WHS finishes 5. supporting TCP_FASTOPEN socket option 6. modifying tcp_check_req() to use to check a TFO socket as well as request_sock 7. supporting TCP's TFO cookie option 8. adding a new SYN-ACK retransmit handler to use the timer directly off the TFO socket rather than the listener socket. Note that TFO server side will not retransmit anything other than SYN-ACK until the 3WHS is completed. The patch also contains an important function "reqsk_fastopen_remove()" to manage the somewhat complex relation between a listener, its request_sock, and the corresponding child socket. See the comment above the function for the detail. Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1485348d |
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30-Jul-2012 |
Ben Hutchings <bhutchings@solarflare.com> |
tcp: Apply device TSO segment limit earlier Cache the device gso_max_segs in sock::sk_gso_max_segs and use it to limit the size of TSO skbs. This avoids the need to fall back to software GSO for local TCP senders. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
42493570 |
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26-Jul-2012 |
Hangbin Liu <liuhangbin@gmail.com> |
tcp: Add TCP_USER_TIMEOUT negative value check TCP_USER_TIMEOUT is a TCP level socket option that takes an unsigned int. But patch "tcp: Add TCP_USER_TIMEOUT socket option"(dca43c75) didn't check the negative values. If a user assign -1 to it, the socket will set successfully and wait for 4294967295 miliseconds. This patch add a negative value check to avoid this issue. Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cf60af03 |
|
19-Jul-2012 |
Yuchung Cheng <ycheng@google.com> |
net-tcp: Fast Open client - sendmsg(MSG_FASTOPEN) sendmsg() (or sendto()) with MSG_FASTOPEN is a combo of connect(2) and write(2). The application should replace connect() with it to send data in the opening SYN packet. For blocking socket, sendmsg() blocks until all the data are buffered locally and the handshake is completed like connect() call. It returns similar errno like connect() if the TCP handshake fails. For non-blocking socket, it returns the number of bytes queued (and transmitted in the SYN-data packet) if cookie is available. If cookie is not available, it transmits a data-less SYN packet with Fast Open cookie request option and returns -EINPROGRESS like connect(). Using MSG_FASTOPEN on connecting or connected socket will result in simlar errno like repeating connect() calls. Therefore the application should only use this flag on new sockets. The buffer size of sendmsg() is independent of the MSS of the connection. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
46d3ceab |
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10-Jul-2012 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: TCP Small Queues This introduce TSQ (TCP Small Queues) TSQ goal is to reduce number of TCP packets in xmit queues (qdisc & device queues), to reduce RTT and cwnd bias, part of the bufferbloat problem. sk->sk_wmem_alloc not allowed to grow above a given limit, allowing no more than ~128KB [1] per tcp socket in qdisc/dev layers at a given time. TSO packets are sized/capped to half the limit, so that we have two TSO packets in flight, allowing better bandwidth use. As a side effect, setting the limit to 40000 automatically reduces the standard gso max limit (65536) to 40000/2 : It can help to reduce latencies of high prio packets, having smaller TSO packets. This means we divert sock_wfree() to a tcp_wfree() handler, to queue/send following frames when skb_orphan() [2] is called for the already queued skbs. Results on my dev machines (tg3/ixgbe nics) are really impressive, using standard pfifo_fast, and with or without TSO/GSO. Without reduction of nominal bandwidth, we have reduction of buffering per bulk sender : < 1ms on Gbit (instead of 50ms with TSO) < 8ms on 100Mbit (instead of 132 ms) I no longer have 4 MBytes backlogged in qdisc by a single netperf session, and both side socket autotuning no longer use 4 Mbytes. As skb destructor cannot restart xmit itself ( as qdisc lock might be taken at this point ), we delegate the work to a tasklet. We use one tasklest per cpu for performance reasons. If tasklet finds a socket owned by the user, it sets TSQ_OWNED flag. This flag is tested in a new protocol method called from release_sock(), to eventually send new segments. [1] New /proc/sys/net/ipv4/tcp_limit_output_bytes tunable [2] skb_orphan() is usually called at TX completion time, but some drivers call it in their start_xmit() handler. These drivers should at least use BQL, or else a single TCP session can still fill the whole NIC TX ring, since TSQ will have no effect. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Dave Taht <dave.taht@bufferbloat.net> Cc: Tom Herbert <therbert@google.com> Cc: Matt Mathis <mattmathis@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Nandita Dukkipati <nanditad@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ae86b9e3 |
|
10-Jul-2012 |
Ben Hutchings <bhutchings@solarflare.com> |
net: Fix non-kernel-doc comments with kernel-doc start marker Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
51c5d0c4 |
|
10-Jul-2012 |
David S. Miller <davem@davemloft.net> |
tcp: Maintain dynamic metrics in local cache. Maintain a local hash table of TCP dynamic metrics blobs. Computed TCP metrics are no longer maintained in the route metrics. The table uses RCU and an extremely simple hash so that it has low latency and low overhead. A simple hash is legitimate because we only make metrics blobs for fully established connections. Some tweaking of the default hash table sizes, metric timeouts, and the hash chain length limit certainly could use some tweaking. But the basic design seems sound. With help from Eric Dumazet and Joe Perches. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
31fe62b9 |
|
23-May-2012 |
Tim Bird <tim.bird@am.sony.com> |
mm: add a low limit to alloc_large_system_hash UDP stack needs a minimum hash size value for proper operation and also uses alloc_large_system_hash() for proper NUMA distribution of its hash tables and automatic sizing depending on available system memory. On some low memory situations, udp_table_init() must ignore the alloc_large_system_hash() result and reallocs a bigger memory area. As we cannot easily free old hash table, we leak it and kmemleak can issue a warning. This patch adds a low limit parameter to alloc_large_system_hash() to solve this problem. We then specify UDP_HTABLE_SIZE_MIN for UDP/UDPLite hash table allocation. Reported-by: Mark Asselstine <mark.asselstine@windriver.com> Reported-by: Tim Bird <tim.bird@am.sony.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
413c27d8 |
|
19-May-2012 |
Eldad Zack <eldad@fogrefinery.com> |
net/ipv4: replace simple_strtoul with kstrtoul Replace simple_strtoul with kstrtoul in three similar occurrences, all setup handlers: * route.c: set_rhash_entries * tcp.c: set_thash_entries * udp.c: set_uhash_entries Also check if the conversion failed. Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bad115cf |
|
17-May-2012 |
Willy Tarreau <w@1wt.eu> |
tcp: do_tcp_sendpages() must try to push data out on oom conditions Since recent changes on TCP splicing (starting with commits 2f533844 "tcp: allow splice() to build full TSO packets" and 35f9c09f "tcp: tcp_sendpages() should call tcp_push() once"), I started seeing massive stalls when forwarding traffic between two sockets using splice() when pipe buffers were larger than socket buffers. Latest changes (net: netdev_alloc_skb() use build_skb()) made the problem even more apparent. The reason seems to be that if do_tcp_sendpages() fails on out of memory condition without being able to send at least one byte, tcp_push() is not called and the buffers cannot be flushed. After applying the attached patch, I cannot reproduce the stalls at all and the data rate it perfectly stable and steady under any condition which previously caused the problem to be permanent. The issue seems to have been there since before the kernel migrated to git, which makes me think that the stalls I occasionally experienced with tux during stress-tests years ago were probably related to the same issue. This issue was first encountered on 3.0.31 and 3.2.17, so please backport to -stable. Signed-off-by: Willy Tarreau <w@1wt.eu> Acked-by: Eric Dumazet <edumazet@google.com> Cc: <stable@vger.kernel.org>
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#
a2a385d6 |
|
16-May-2012 |
Eric Dumazet <edumazet@google.com> |
tcp: bool conversions bool conversions where possible. __inline__ -> inline space cleanups Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
dc6b9b78 |
|
16-May-2012 |
Eric Dumazet <edumazet@google.com> |
net: include/net/sock.h cleanup bool/const conversions where possible __inline__ -> inline space cleanups Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e87cc472 |
|
13-May-2012 |
Joe Perches <joe@perches.com> |
net: Convert net_ratelimit uses to net_<level>_ratelimited Standardize the net core ratelimited logging functions. Coalesce formats, align arguments. Change a printk then vprintk sequence to use printf extension %pV. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
292e8d8c |
|
09-May-2012 |
Pavel Emelyanov <xemul@parallels.com> |
tcp: Move rcvq sending to tcp_input.c It actually works on the input queue and will use its read mem routines, thus it's better to have in in the tcp_input.c file. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
b081f85c |
|
02-May-2012 |
Eric Dumazet <edumazet@google.com> |
net: implement tcp coalescing in tcp_queue_rcv() Extend tcp coalescing implementing it from tcp_queue_rcv(), the main receiver function when application is not blocked in recvmsg(). Function tcp_queue_rcv() is moved a bit to allow its call from tcp_data_queue() This gives good results especially if GRO could not kick, and if skb head is a fragment. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b49960a0 |
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01-May-2012 |
Eric Dumazet <edumazet@google.com> |
tcp: change tcp_adv_win_scale and tcp_rmem[2] tcp_adv_win_scale default value is 2, meaning we expect a good citizen skb to have skb->len / skb->truesize ratio of 75% (3/4) In 2.6 kernels we (mis)accounted for typical MSS=1460 frame : 1536 + 64 + 256 = 1856 'estimated truesize', and 1856 * 3/4 = 1392. So these skbs were considered as not bloated. With recent truesize fixes, a typical MSS=1460 frame truesize is now the more precise : 2048 + 256 = 2304. But 2304 * 3/4 = 1728. So these skb are not good citizen anymore, because 1460 < 1728 (GRO can escape this problem because it build skbs with a too low truesize.) This also means tcp advertises a too optimistic window for a given allocated rcvspace : When receiving frames, sk_rmem_alloc can hit sk_rcvbuf limit and we call tcp_prune_queue()/tcp_collapse() too often, especially when application is slow to drain its receive queue or in case of losses (netperf is fast, scp is slow). This is a major latency source. We should adjust the len/truesize ratio to 50% instead of 75% This patch : 1) changes tcp_adv_win_scale default to 1 instead of 2 2) increase tcp_rmem[2] limit from 4MB to 6MB to take into account better truesize tracking and to allow autotuning tcp receive window to reach same value than before. Note that same amount of kernel memory is consumed compared to 2.6 kernels. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
eed530b6 |
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02-May-2012 |
Yuchung Cheng <ycheng@google.com> |
tcp: early retransmit This patch implements RFC 5827 early retransmit (ER) for TCP. It reduces DUPACK threshold (dupthresh) if outstanding packets are less than 4 to recover losses by fast recovery instead of timeout. While the algorithm is simple, small but frequent network reordering makes this feature dangerous: the connection repeatedly enter false recovery and degrade performance. Therefore we implement a mitigation suggested in the appendix of the RFC that delays entering fast recovery by a small interval, i.e., RTT/4. Currently ER is conservative and is disabled for the rest of the connection after the first reordering event. A large scale web server experiment on the performance impact of ER is summarized in section 6 of the paper "Proportional Rate Reduction for TCP”, IMC 2011. http://conferences.sigcomm.org/imc/2011/docs/p155.pdf Note that Linux has a similar feature called THIN_DUPACK. The differences are THIN_DUPACK do not mitigate reorderings and is only used after slow start. Currently ER is disabled if THIN_DUPACK is enabled. I would be happy to merge THIN_DUPACK feature with ER if people think it's a good idea. ER is enabled by sysctl_tcp_early_retrans: 0: Disables ER 1: Reduce dupthresh to packets_out - 1 when outstanding packets < 4. 2: (Default) reduce dupthresh like mode 1. In addition, delay entering fast recovery by RTT/4. Note: mode 2 is implemented in the third part of this patch series. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
de248a75 |
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25-Apr-2012 |
Pavel Emelyanov <xemul@parallels.com> |
tcp repair: Fix unaligned access when repairing options (v2) Don't pick __u8/__u16 values directly from raw pointers, but instead use an array of structures of code:value pairs. This is OK, since the buffer we take options from is not an skb memory, but a user-to-kernel one. For those options which don't require any value now, require this to be zero (for potential future extension of this API). v2: Changed tcp_repair_opt to use two __u32-s as spotted by David Laight. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
38ba0a65 |
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23-Apr-2012 |
Eric Dumazet <edumazet@google.com> |
net: skb_can_coalesce returns a boolean Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
900f65d3 |
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19-Apr-2012 |
Neal Cardwell <ncardwell@google.com> |
tcp: move duplicate code from tcp_v4_init_sock()/tcp_v6_init_sock() This commit moves the (substantial) common code shared between tcp_v4_init_sock() and tcp_v6_init_sock() to a new address-family independent function, tcp_init_sock(). Centralizing this functionality should help avoid drift issues, e.g. where the IPv4 side is updated without a corresponding update to IPv6. There was already some drift: IPv4 initialized snd_cwnd to TCP_INIT_CWND, while the IPv6 side was still initializing snd_cwnd to 2 (in this case it should not matter, since snd_cwnd is also initialized in tcp_init_metrics(), but the general risks and maintenance overhead remain). When diffing the old and new code, note that new tcp_init_sock() function uses the order of steps from the tcp_v4_init_sock() implementation (the order is slightly different in tcp_v6_init_sock()). Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b139ba4e |
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18-Apr-2012 |
Pavel Emelyanov <xemul@parallels.com> |
tcp: Repair connection-time negotiated parameters There are options, which are set up on a socket while performing TCP handshake. Need to resurrect them on a socket while repairing. A new sockoption accepts a buffer and parses it. The buffer should be CODE:VALUE sequence of bytes, where CODE is standard option code and VALUE is the respective value. Only 4 options should be handled on repaired socket. To read 3 out of 4 of these options the TCP_INFO sockoption can be used. An ability to get the last one (the mss_clamp) was added by the previous patch. Now the restore. Three of these options -- timestamp_ok, mss_clamp and snd_wscale -- are just restored on a coket. The sack_ok flags has 2 issues. First, whether or not to do sacks at all. This flag is just read and set back. No other sack info is saved or restored, since according to the standart and the code dropping all sack-ed segments is OK, the sender will resubmit them again, so after the repair we will probably experience a pause in connection. Next, the fack bit. It's just set back on a socket if the respective sysctl is set. No collected stats about packets flow is preserved. As far as I see (plz, correct me if I'm wrong) the fack-based congestion algorithm survives dropping all of the stats and repairs itself eventually, probably losing the performance for that period. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5e6a3ce6 |
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18-Apr-2012 |
Pavel Emelyanov <xemul@parallels.com> |
tcp: Report mss_clamp with TCP_MAXSEG option in repair mode The mss_clamp is the only connection-time negotiated option which cannot be obtained from the user space. Make the TCP_MAXSEG sockopt report one in the repair mode. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c0e88ff0 |
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18-Apr-2012 |
Pavel Emelyanov <xemul@parallels.com> |
tcp: Repair socket queues Reading queues under repair mode is done with recvmsg call. The queue-under-repair set by TCP_REPAIR_QUEUE option is used to determine which queue should be read. Thus both send and receive queue can be read with this. Caller must pass the MSG_PEEK flag. Writing to queues is done with sendmsg call and yet again -- the repair-queue option can be used to push data into the receive queue. When putting an skb into receive queue a zero tcp header is appented to its head to address the tcp_hdr(skb)->syn and the ->fin checks by the (after repair) tcp_recvmsg. These flags flags are both set to zero and that's why. The fin cannot be met in the queue while reading the source socket, since the repair only works for closed/established sockets and queueing fin packet always changes its state. The syn in the queue denotes that the respective skb's seq is "off-by-one" as compared to the actual payload lenght. Thus, at the rcv queue refill we can just drop this flag and set the skb's sequences to precice values. When the repair mode is turned off, the write queue seqs are updated so that the whole queue is considered to be 'already sent, waiting for ACKs' (write_seq = snd_nxt <= snd_una). From the protocol POV the send queue looks like it was sent, but the data between the write_seq and snd_nxt is lost in the network. This helps to avoid another sockoption for setting the snd_nxt sequence. Leaving the whole queue in a 'not yet sent' state (as it will be after sendmsg-s) will not allow to receive any acks from the peer since the ack_seq will be after the snd_nxt. Thus even the ack for the window probe will be dropped and the connection will be 'locked' with the zero peer window. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ee995283 |
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18-Apr-2012 |
Pavel Emelyanov <xemul@parallels.com> |
tcp: Initial repair mode This includes (according the the previous description): * TCP_REPAIR sockoption This one just puts the socket in/out of the repair mode. Allowed for CAP_NET_ADMIN and for closed/establised sockets only. When repair mode is turned off and the socket happens to be in the established state the window probe is sent to the peer to 'unlock' the connection. * TCP_REPAIR_QUEUE sockoption This one sets the queue which we're about to repair. The 'no-queue' is set by default. * TCP_QUEUE_SEQ socoption Sets the write_seq/rcv_nxt of a selected repaired queue. Allowed for TCP_CLOSE-d sockets only. When the socket changes its state the other seq-s are changed by the kernel according to the protocol rules (most of the existing code is actually reused). * Ability to forcibly bind a socket to a port The sk->sk_reuse is set to SK_FORCE_REUSE. * Immediate connect modification The connect syscall initializes the connection, then directly jumps to the code which finalizes it. * Silent close modification The close just aborts the connection (similar to SO_LINGER with 0 time) but without sending any FIN/RST-s to peer. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
370816ae |
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18-Apr-2012 |
Pavel Emelyanov <xemul@parallels.com> |
tcp: Move code around This is just the preparation patch, which makes the needed for TCP repair code ready for use. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
95c96174 |
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14-Apr-2012 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: cleanup unsigned to unsigned int Use of "unsigned int" is preferred to bare "unsigned" in net tree. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a21d4572 |
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10-Apr-2012 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: avoid order-1 allocations on wifi and tx path Marc Merlin reported many order-1 allocations failures in TX path on its wireless setup, that dont make any sense with MTU=1500 network, and non SG capable hardware. After investigation, it turns out TCP uses sk_stream_alloc_skb() and used as a convention skb_tailroom(skb) to know how many bytes of data payload could be put in this skb (for non SG capable devices) Note : these skb used kmalloc-4096 (MTU=1500 + MAX_HEADER + sizeof(struct skb_shared_info) being above 2048) Later, mac80211 layer need to add some bytes at the tail of skb (IEEE80211_ENCRYPT_TAILROOM = 18 bytes) and since no more tailroom is available has to call pskb_expand_head() and request order-1 allocations. This patch changes sk_stream_alloc_skb() so that only sk->sk_prot->max_header bytes of headroom are reserved, and use a new skb field, avail_size to hold the data payload limit. This way, order-0 allocations done by TCP stack can leave more than 2 KB of tailroom and no more allocation is performed in mac80211 layer (or any layer needing some tailroom) avail_size is unioned with mark/dropcount, since mark will be set later in IP stack for output packets. Therefore, skb size is unchanged. Reported-by: Marc MERLIN <marc@merlins.org> Tested-by: Marc MERLIN <marc@merlins.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5fb84b14 |
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09-Apr-2012 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: restore correct limit Commit c43b874d5d714f (tcp: properly initialize tcp memory limits) tried to fix a regression added in commits 4acb4190 & 3dc43e3, but still get it wrong. Result is machines with low amount of memory have too small tcp_rmem[2] value and slow tcp receives : Per socket limit being 1/1024 of memory instead of 1/128 in old kernels, so rcv window is capped to small values. Fix this to match comment and previous behavior. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Glauber Costa <glommer@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
35f9c09f |
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04-Apr-2012 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: tcp_sendpages() should call tcp_push() once commit 2f533844242 (tcp: allow splice() to build full TSO packets) added a regression for splice() calls using SPLICE_F_MORE. We need to call tcp_flush() at the end of the last page processed in tcp_sendpages(), or else transmits can be deferred and future sends stall. Add a new internal flag, MSG_SENDPAGE_NOTLAST, acting like MSG_MORE, but with different semantic. For all sendpage() providers, its a transparent change. Only sock_sendpage() and tcp_sendpages() can differentiate the two different flags provided by pipe_to_sendpage() Reported-by: Tom Herbert <therbert@google.com> Cc: Nandita Dukkipati <nanditad@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: H.K. Jerry Chu <hkchu@google.com> Cc: Maciej Żenczykowski <maze@google.com> Cc: Mahesh Bandewar <maheshb@google.com> Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: Eric Dumazet <eric.dumazet@gmail>com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a2bd1140 |
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04-Apr-2012 |
Dave Jiang <dave.jiang@intel.com> |
netdma: adding alignment check for NETDMA ops This is the fallout from adding memcpy alignment workaround for certain IOATDMA hardware. NetDMA will only use DMA engine that can handle byte align ops. Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
2f533844 |
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03-Apr-2012 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: allow splice() to build full TSO packets vmsplice()/splice(pipe, socket) call do_tcp_sendpages() one page at a time, adding at most 4096 bytes to an skb. (assuming PAGE_SIZE=4096) The call to tcp_push() at the end of do_tcp_sendpages() forces an immediate xmit when pipe is not already filled, and tso_fragment() try to split these skb to MSS multiples. 4096 bytes are usually split in a skb with 2 MSS, and a remaining sub-mss skb (assuming MTU=1500) This makes slow start suboptimal because many small frames are sent to qdisc/driver layers instead of big ones (constrained by cwnd and packets in flight of course) In fact, applications using sendmsg() (adding an additional memory copy) instead of vmsplice()/splice()/sendfile() are a bit faster because of this anomaly, especially if serving small files in environments with large initial [c]wnd. Call tcp_push() only if MSG_MORE is not set in the flags parameter. This bit is automatically provided by splice() internals but for the last page, or on all pages if user specified SPLICE_F_MORE splice() flag. In some workloads, this can reduce number of sent logical packets by an order of magnitude, making zero-copy TCP actually faster than one-copy :) Reported-by: Tom Herbert <therbert@google.com> Cc: Nandita Dukkipati <nanditad@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: H.K. Jerry Chu <hkchu@google.com> Cc: Maciej Żenczykowski <maze@google.com> Cc: Mahesh Bandewar <maheshb@google.com> Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: Eric Dumazet <eric.dumazet@gmail>com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
afd46503 |
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12-Mar-2012 |
Joe Perches <joe@perches.com> |
net: ipv4: Standardize prefixes for message logging Add #define pr_fmt(fmt) as appropriate. Add "IPv4: ", "TCP: ", and "IPsec: " to appropriate files. Standardize on "UDPLite: " for appropriate uses. Some prefixes were previously "UDPLITE: " and "UDP-Lite: ". Add KBUILD_MODNAME ": " to icmp and gre. Remove embedded prefixes as appropriate. Add missing "\n" to pr_info in gre.c. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
058bd4d2 |
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11-Mar-2012 |
Joe Perches <joe@perches.com> |
net: Convert printks to pr_<level> Use a more current kernel messaging style. Convert a printk block to print_hex_dump. Coalesce formats, align arguments. Use %s, __func__ instead of embedding function names. Some messages that were prefixed with <foo>_close are now prefixed with <foo>_fini. Some ah4 and esp messages are now not prefixed with "ip ". The intent of this patch is to later add something like #define pr_fmt(fmt) "IPv4: " fmt. to standardize the output messages. Text size is trivially reduced. (x86-32 allyesconfig) $ size net/ipv4/built-in.o* text data bss dec hex filename 887888 31558 249696 1169142 11d6f6 net/ipv4/built-in.o.new 887934 31558 249800 1169292 11d78c net/ipv4/built-in.o.old Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
074b8517 |
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08-Feb-2012 |
Dimitri Sivanich <sivanich@sgi.com> |
vfs: fix panic in __d_lookup() with high dentry hashtable counts When the number of dentry cache hash table entries gets too high (2147483648 entries), as happens by default on a 16TB system, use of a signed integer in the dcache_init() initialization loop prevents the dentry_hashtable from getting initialized, causing a panic in __d_lookup(). Fix this in dcache_init() and similar areas. Signed-off-by: Dimitri Sivanich <sivanich@sgi.com> Acked-by: David S. Miller <davem@davemloft.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
c43b874d |
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01-Feb-2012 |
Jason Wang <jasowang@redhat.com> |
tcp: properly initialize tcp memory limits Commit 4acb4190 tries to fix the using uninitialized value introduced by commit 3dc43e3, but it would make the per-socket memory limits too small. This patch fixes this and also remove the redundant codes introduced in 4acb4190. Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Glauber Costa <glommer@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
efcdbf24 |
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30-Jan-2012 |
Arun Sharma <asharma@fb.com> |
net: Disambiguate kernel message Some of our machines were reporting: TCP: too many of orphaned sockets even when the number of orphaned sockets was well below the limit. We print a different message depending on whether we're out of TCP memory or there are too many orphaned sockets. Also move the check out of line and cleanup the messages that were printed. Signed-off-by: Arun Sharma <asharma@fb.com> Suggested-by: Mohan Srinivasan <mohan@fb.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: David Miller <davem@davemloft.net> Cc: Glauber Costa <glommer@parallels.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4acb4190 |
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29-Jan-2012 |
Glauber Costa <glommer@parallels.com> |
net/tcp: Fix tcp memory limits initialization when !CONFIG_SYSCTL sysctl_tcp_mem() initialization was moved to sysctl_tcp_ipv4.c in commit 3dc43e3e4d0b52197d3205214fe8f162f9e0c334, since it became a per-ns value. That code, however, will never run when CONFIG_SYSCTL is disabled, leading to bogus values on those fields - causing hung TCP sockets. This patch fixes it by keeping an initialization code in tcp_init(). It will be overwritten by the first net namespace init if CONFIG_SYSCTL is compiled in, and do the right thing if it is compiled out. It is also named properly as tcp_init_mem(), to properly signal its non-sysctl side effect on TCP limits. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: David S. Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/4F22D05A.8030604@parallels.com [ renamed the function, tidied up the changelog a bit ] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3dc43e3e |
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11-Dec-2011 |
Glauber Costa <glommer@parallels.com> |
per-netns ipv4 sysctl_tcp_mem This patch allows each namespace to independently set up its levels for tcp memory pressure thresholds. This patch alone does not buy much: we need to make this values per group of process somehow. This is achieved in the patches that follows in this patchset. Signed-off-by: Glauber Costa <glommer@parallels.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> CC: David S. Miller <davem@davemloft.net> CC: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0a5912db |
|
04-Dec-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: remove TCP_OFF and TCP_PAGE macros As mentioned by Joe Perches, TCP_OFF() and TCP_PAGE() macros are useless. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
761965ea |
|
04-Dec-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: tcp_sendmsg() page recycling If our TCP_PAGE(sk) is not shared (page_count() == 1), we can set page offset to 0. This permits better filling of the pages on small to medium tcp writes. "tbench 16" results on my dev server (2x4x2 machine) : Before : 3072 MB/s After : 3146 MB/s (2.4 % gain) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f07d960d |
|
28-Nov-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: avoid frag allocation for small frames tcp_sendmsg() uses select_size() helper to choose skb head size when a new skb must be allocated. If GSO is enabled for the socket, current strategy is to force all payload data to be outside of headroom, in PAGE fragments. This strategy is not welcome for small packets, wasting memory. Experiments show that best results are obtained when using 2048 bytes for skb head (This includes the skb overhead and various headers) This patch provides better len/truesize ratios for packets sent to loopback device, and reduce memory needs for in-flight loopback packets, particularly on arches with big pages. If a sender sends many 1-byte packets to an unresponsive application, receiver rmem_alloc will grow faster and will stop queuing these packets sooner, or will collapse its receive queue to free excess memory. netperf -t TCP_RR results are improved by ~4 %, and many workloads are improved as well (tbench, mysql...) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
690e99c4 |
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27-Nov-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: tcp_sendmsg() wrong access to sk_route_caps Now sk_route_caps is u64, its dangerous to use an integer to store result of an AND operator. It wont work if NETIF_F_SG is moved on the upper part of u64. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c8f44aff |
|
15-Nov-2011 |
Michał Mirosław <mirq-linux@rere.qmqm.pl> |
net: introduce and use netdev_features_t for device features sets v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
78d81d15 |
|
24-Oct-2011 |
Flavio Leitner <fbl@redhat.com> |
TCP: remove TCP_DEBUG It was enabled by default and the messages guarded by the define are useful. Signed-off-by: Flavio Leitner <fbl@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ca35a0ef |
|
23-Oct-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: md5: dont write skb head in tcp_md5_hash_header() tcp_md5_hash_header() writes into skb header a temporary zero value, this might confuse other users of this area. Since tcphdr is small (20 bytes), copy it in a temporary variable and make the change in the copy. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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cf533ea5 |
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21-Oct-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: add const qualifiers where possible Adding const qualifiers to pointers can ease code review, and spot some bugs. It might allow compiler to optimize code further. For example, is it legal to temporary write a null cksum into tcphdr in tcp_md5_hash_header() ? I am afraid a sniffer could catch the temporary null value... Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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9e903e08 |
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18-Oct-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: add skb frag size accessors To ease skb->truesize sanitization, its better to be able to localize all references to skb frags size. Define accessors : skb_frag_size() to fetch frag size, and skb_frag_size_{set|add|sub}() to manipulate it. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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b5c5693b |
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03-Oct-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: report ECN_SEEN in tcp_info Allows ss command (iproute2) to display "ecnseen" if at least one packet with ECT(0) or ECT(1) or ECN was received by this socket. "ecn" means ECN was negotiated at session establishment (TCP level) "ecnseen" means we received at least one packet with ECT fields set (IP level) ss -i ... ESTAB 0 0 192.168.20.110:22 192.168.20.144:38016 ino:5950 sk:f178e400 mem:(r0,w0,f0,t0) ts sack ecn ecnseen bic wscale:7,8 rto:210 rtt:12.5/7.5 cwnd:10 send 9.3Mbps rcv_space:14480 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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4de075e0 |
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27-Sep-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: rename tcp_skb_cb flags Rename struct tcp_skb_cb "flags" to "tcp_flags" to ease code review and maintenance. Its content is a combination of FIN/SYN/RST/PSH/ACK/URG/ECE/CWR flags Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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765cf997 |
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12-Sep-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: md5: remove one indirection level in tcp_md5sig_pool tcp_md5sig_pool is currently an 'array' (a percpu object) of pointers to struct tcp_md5sig_pool. Only the pointers are NUMA aware, but objects themselves are all allocated on a single node. Remove this extra indirection to get proper percpu memory (NUMA aware) and make code simpler. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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aff65da0 |
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22-Aug-2011 |
Ian Campbell <Ian.Campbell@citrix.com> |
net: ipv4: convert to SKB frag APIs Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: "Pekka Savola (ipv6)" <pekkas@netcore.fi> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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f03d78db |
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07-Jul-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: refine {udp|tcp|sctp}_mem limits Current tcp/udp/sctp global memory limits are not taking into account hugepages allocations, and allow 50% of ram to be used by buffers of a single protocol [ not counting space used by sockets / inodes ...] Lets use nr_free_buffer_pages() and allow a default of 1/8 of kernel ram per protocol, and a minimum of 128 pages. Heavy duty machines sysadmins probably need to tweak limits anyway. References: https://bugzilla.stlinux.com/show_bug.cgi?id=38032 Reported-by: starlight <starlight@binnacle.cx> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c6e1a0d1 |
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04-Apr-2011 |
Tom Herbert <therbert@google.com> |
net: Allow no-cache copy from user on transmit This patch uses __copy_from_user_nocache on transmit to bypass data cache for a performance improvement. skb_add_data_nocache and skb_copy_to_page_nocache can be called by sendmsg functions to use this feature, initial support is in tcp_sendmsg. This functionality is configurable per device using ethtool. Presumably, this feature would only be useful when the driver does not touch the data. The feature is turned on by default if a device indicates that it does some form of checksum offload; it is off by default for devices that do no checksum offload or indicate no checksum is necessary. For the former case copy-checksum is probably done anyway, in the latter case the device is likely loopback in which case the no cache copy is probably not beneficial. This patch was tested using 200 instances of netperf TCP_RR with 1400 byte request and one byte reply. Platform is 16 core AMD x86. No-cache copy disabled: 672703 tps, 97.13% utilization 50/90/99% latency:244.31 484.205 1028.41 No-cache copy enabled: 702113 tps, 96.16% utilization, 50/90/99% latency 238.56 467.56 956.955 Using 14000 byte request and response sizes demonstrate the effects more dramatically: No-cache copy disabled: 79571 tps, 34.34 %utlization 50/90/95% latency 1584.46 2319.59 5001.76 No-cache copy enabled: 83856 tps, 34.81% utilization 50/90/95% latency 2508.42 2622.62 2735.88 Note especially the effect on latency tail (95th percentile). This seems to provide a nice performance improvement and is consistent in the tests I ran. Presumably, this would provide the greatest benfits in the presence of an application workload stressing the cache and a lot of transmit data happening. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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2f4e1b39 |
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09-Mar-2011 |
Mario Schuknecht <m.schuknecht@dresearch.de> |
tcp: ioctl type SIOCOUTQNSD returns amount of data not sent In contrast to SIOCOUTQ which returns the amount of data sent but not yet acknowledged plus data not yet sent this patch only returns the data not sent. For various methods of live streaming bitrate control it may be helpful to know how much data are in the tcp outqueue are not sent yet. Signed-off-by: Mario Schuknecht <m.schuknecht@dresearch.de> Signed-off-by: Steffen Sledz <sledz@dresearch.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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089c3482 |
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19-Feb-2011 |
Shan Wei <shanwei@cn.fujitsu.com> |
tcp: Remove debug macro of TCP_CHECK_TIMER Now, TCP_CHECK_TIMER is not used for debuging, it does nothing. And, it has been there for several years, maybe 6 years. Remove it to keep code clearer. Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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04ed3e74 |
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24-Jan-2011 |
Michał Mirosław <mirq-linux@rere.qmqm.pl> |
net: change netdev->features to u32 Quoting Ben Hutchings: we presumably won't be defining features that can only be enabled on 64-bit architectures. Occurences found by `grep -r` on net/, drivers/net, include/ [ Move features and vlan_features next to each other in struct netdev, as per Eric Dumazet's suggestion -DaveM ] Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
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c39508d6 |
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24-Nov-2010 |
David S. Miller <davem@davemloft.net> |
tcp: Make TCP_MAXSEG minimum more correct. Use TCP_MIN_MSS instead of constant 64. Reported-by: Min Zhang <mzhang@mvista.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7a1abd08 |
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10-Nov-2010 |
David S. Miller <davem@davemloft.net> |
tcp: Increase TCP_MAXSEG socket option minimum. As noted by Steve Chen, since commit f5fff5dc8a7a3f395b0525c02ba92c95d42b7390 ("tcp: advertise MSS requested by user") we can end up with a situation where tcp_select_initial_window() does a divide by a zero (or even negative) mss value. The problem is that sometimes we effectively subtract TCPOLEN_TSTAMP_ALIGNED and/or TCPOLEN_MD5SIG_ALIGNED from the mss. Fix this by increasing the minimum from 8 to 64. Reported-by: Steve Chen <schen@mvista.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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8d987e5c |
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09-Nov-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: avoid limits overflow Robin Holt tried to boot a 16TB machine and found some limits were reached : sysctl_tcp_mem[2], sysctl_udp_mem[2] We can switch infrastructure to use long "instead" of "int", now atomic_long_t primitives are available for free. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Reported-by: Robin Holt <holt@sgi.com> Reviewed-by: Robin Holt <holt@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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2af6fd8b |
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30-Oct-2010 |
Joe Perches <joe@perches.com> |
net/ipv4/tcp.c: Update WARN uses Coalesce long formats. Align arguments. Remove KERN_<level>. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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01db403c |
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27-Sep-2010 |
David S. Miller <davem@davemloft.net> |
tcp: Fix >4GB writes on 64-bit. Fixes kernel bugzilla #16603 tcp_sendmsg() truncates iov_len to an 'int' which a 4GB write to write zero bytes, for example. There is also the problem higher up of how verify_iovec() works. It wants to prevent the total length from looking like an error return value. However it does this using 'int', but syscalls return 'long' (and thus signed 64-bit on 64-bit machines). So it could trigger false-positives on 64-bit as written. So fix it to use 'long'. Reported-by: Olaf Bonorden <bono@onlinehome.de> Reported-by: Daniel Büse <dbuese@gmx.de> Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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a4d25803 |
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20-Sep-2010 |
Tom Marshall <tdm.code@gmail.com> |
tcp: Fix race in tcp_poll If a RST comes in immediately after checking sk->sk_err, tcp_poll will return POLLIN but not POLLOUT. Fix this by checking sk->sk_err at the end of tcp_poll. Additionally, ensure the correct order of operations on SMP machines with memory barriers. Signed-off-by: Tom Marshall <tdm.code@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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dca43c75 |
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27-Aug-2010 |
Jerry Chu <hkchu@google.com> |
tcp: Add TCP_USER_TIMEOUT socket option. This patch provides a "user timeout" support as described in RFC793. The socket option is also needed for the the local half of RFC5482 "TCP User Timeout Option". TCP_USER_TIMEOUT is a TCP level socket option that takes an unsigned int, when > 0, to specify the maximum amount of time in ms that transmitted data may remain unacknowledged before TCP will forcefully close the corresponding connection and return ETIMEDOUT to the application. If 0 is given, TCP will continue to use the system default. Increasing the user timeouts allows a TCP connection to survive extended periods without end-to-end connectivity. Decreasing the user timeouts allows applications to "fail fast" if so desired. Otherwise it may take upto 20 minutes with the current system defaults in a normal WAN environment. The socket option can be made during any state of a TCP connection, but is only effective during the synchronized states of a connection (ESTABLISHED, FIN-WAIT-1, FIN-WAIT-2, CLOSE-WAIT, CLOSING, or LAST-ACK). Moreover, when used with the TCP keepalive (SO_KEEPALIVE) option, TCP_USER_TIMEOUT will overtake keepalive to determine when to close a connection due to keepalive failure. The option does not change in anyway when TCP retransmits a packet, nor when a keepalive probe will be sent. This option, like many others, will be inherited by an acceptor from its listener. Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d84ba638 |
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24-Aug-2010 |
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> |
tcp: select(writefds) don't hang up when a peer close connection This issue come from ruby language community. Below test program hang up when only run on Linux. % uname -mrsv Linux 2.6.26-2-486 #1 Sat Dec 26 08:37:39 UTC 2009 i686 % ruby -rsocket -ve ' BasicSocket.do_not_reverse_lookup = true serv = TCPServer.open("127.0.0.1", 0) s1 = TCPSocket.open("127.0.0.1", serv.addr[1]) s2 = serv.accept s2.close s1.write("a") rescue p $! s1.write("a") rescue p $! Thread.new { s1.write("a") }.join' ruby 1.9.3dev (2010-07-06 trunk 28554) [i686-linux] #<Errno::EPIPE: Broken pipe> [Hang Here] FreeBSD, Solaris, Mac doesn't. because Ruby's write() method call select() internally. and tcp_poll has a bug. SUS defined 'ready for writing' of select() as following. | A descriptor shall be considered ready for writing when a call to an output | function with O_NONBLOCK clear would not block, whether or not the function | would transfer data successfully. That said, EPIPE situation is clearly one of 'ready for writing'. We don't have read-side issue because tcp_poll() already has read side shutdown care. | if (sk->sk_shutdown & RCV_SHUTDOWN) | mask |= POLLIN | POLLRDNORM | POLLRDHUP; So, Let's insert same logic in write side. - reference url http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/31065 http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/31068 Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c5ed63d6 |
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26-Aug-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: fix three tcp sysctls tuning As discovered by Anton Blanchard, current code to autotune tcp_death_row.sysctl_max_tw_buckets, sysctl_tcp_max_orphans and sysctl_max_syn_backlog makes little sense. The bigger a page is, the less tcp_max_orphans is : 4096 on a 512GB machine in Anton's case. (tcp_hashinfo.bhash_size * sizeof(struct inet_bind_hashbucket)) is much bigger if spinlock debugging is on. Its wrong to select bigger limits in this case (where kernel structures are also bigger) bhash_size max is 65536, and we get this value even for small machines. A better ground is to use size of ehash table, this also makes code shorter and more obvious. Based on a patch from Anton, and another from David. Reported-and-tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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ad1af0fe |
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25-Aug-2010 |
David S. Miller <davem@davemloft.net> |
tcp: Combat per-cpu skew in orphan tests. As reported by Anton Blanchard when we use percpu_counter_read_positive() to make our orphan socket limit checks, the check can be off by up to num_cpus_online() * batch (which is 32 by default) which on a 128 cpu machine can be as large as the default orphan limit itself. Fix this by doing the full expensive sum check if the optimized check triggers. Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
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3c0fef0b |
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30-Jul-2010 |
Josh Hunt <johunt@akamai.com> |
net: Add getsockopt support for TCP thin-streams Initial TCP thin-stream commit did not add getsockopt support for the new socket options: TCP_THIN_LINEAR_TIMEOUTS and TCP_THIN_DUPACK. This adds support for them. Signed-off-by: Josh Hunt <johunt@akamai.com> Tested-by: Andreas Petlund <apetlund@simula.no> Acked-by: Andreas Petlund <apetlund@simula.no> Signed-off-by: David S. Miller <davem@davemloft.net>
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a3bdb549 |
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28-Jul-2010 |
Dmitry Popov <dp@highloadlab.com> |
tcp: cookie transactions setsockopt memory leak There is a bug in do_tcp_setsockopt(net/ipv4/tcp.c), TCP_COOKIE_TRANSACTIONS case. In some cases (when tp->cookie_values == NULL) new tcp_cookie_values structure can be allocated (at cvp), but not bound to tp->cookie_values. So a memory leak occurs. Signed-off-by: Dmitry Popov <dp@highloadlab.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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3a047bf8 |
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12-Jul-2010 |
Changli Gao <xiaosuo@gmail.com> |
rfs: call sock_rps_record_flow() in tcp_splice_read() rfs: call sock_rps_record_flow() in tcp_splice_read() call sock_rps_record_flow() in tcp_splice_read(), so the applications using splice(2) or sendfile(2) can utilize RFS. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- net/ipv4/tcp.c | 1 + 1 file changed, 1 insertion(+) Signed-off-by: David S. Miller <davem@davemloft.net>
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7ba42910 |
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10-Jul-2010 |
Changli Gao <xiaosuo@gmail.com> |
inet, inet6: make tcp_sendmsg() and tcp_sendpage() through inet_sendmsg() and inet_sendpage() a new boolean flag no_autobind is added to structure proto to avoid the autobind calls when the protocol is TCP. Then sock_rps_record_flow() is called int the TCP's sendmsg() and sendpage() pathes. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- include/net/inet_common.h | 4 ++++ include/net/sock.h | 1 + include/net/tcp.h | 8 ++++---- net/ipv4/af_inet.c | 15 +++++++++------ net/ipv4/tcp.c | 11 +++++------ net/ipv4/tcp_ipv4.c | 3 +++ net/ipv6/af_inet6.c | 8 ++++---- net/ipv6/tcp_ipv6.c | 3 +++ 8 files changed, 33 insertions(+), 20 deletions(-) Signed-off-by: David S. Miller <davem@davemloft.net>
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4bc2f18b |
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09-Jul-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
net/ipv4: EXPORT_SYMBOL cleanups CodingStyle cleanups EXPORT_SYMBOL should immediately follow the symbol declaration. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7a9b2d59 |
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23-Jun-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: use this_cpu_ptr() use this_cpu_ptr(p) instead of per_cpu_ptr(p, smp_processor_id()) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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565b7b2d |
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24-Jun-2010 |
Konstantin Khorenko <khorenko@openvz.org> |
tcp: do not send reset to already closed sockets i've found that tcp_close() can be called for an already closed socket, but still sends reset in this case (tcp_send_active_reset()) which seems to be incorrect. Moreover, a packet with reset is sent with different source port as original port number has been already cleared on socket. Besides that incrementing stat counter for LINUX_MIB_TCPABORTONCLOSE also does not look correct in this case. Initially this issue was found on 2.6.18-x RHEL5 kernel, but the same seems to be true for the current mainstream kernel (checked on 2.6.35-rc3). Please, correct me if i missed something. How that happens: 1) the server receives a packet for socket in TCP_CLOSE_WAIT state that triggers a tcp_reset(): Call Trace: <IRQ> [<ffffffff8025b9b9>] tcp_reset+0x12f/0x1e8 [<ffffffff80046125>] tcp_rcv_state_process+0x1c0/0xa08 [<ffffffff8003eb22>] tcp_v4_do_rcv+0x310/0x37a [<ffffffff80028bea>] tcp_v4_rcv+0x74d/0xb43 [<ffffffff8024ef4c>] ip_local_deliver_finish+0x0/0x259 [<ffffffff80037131>] ip_local_deliver+0x200/0x2f4 [<ffffffff8003843c>] ip_rcv+0x64c/0x69f [<ffffffff80021d89>] netif_receive_skb+0x4c4/0x4fa [<ffffffff80032eca>] process_backlog+0x90/0xec [<ffffffff8000cc50>] net_rx_action+0xbb/0x1f1 [<ffffffff80012d3a>] __do_softirq+0xf5/0x1ce [<ffffffff8001147a>] handle_IRQ_event+0x56/0xb0 [<ffffffff8006334c>] call_softirq+0x1c/0x28 [<ffffffff80070476>] do_softirq+0x2c/0x85 [<ffffffff80070441>] do_IRQ+0x149/0x152 [<ffffffff80062665>] ret_from_intr+0x0/0xa <EOI> [<ffffffff80008a2e>] __handle_mm_fault+0x6cd/0x1303 [<ffffffff80008903>] __handle_mm_fault+0x5a2/0x1303 [<ffffffff80033a9d>] cache_free_debugcheck+0x21f/0x22e [<ffffffff8006a263>] do_page_fault+0x49a/0x7dc [<ffffffff80066487>] thread_return+0x89/0x174 [<ffffffff800c5aee>] audit_syscall_exit+0x341/0x35c [<ffffffff80062e39>] error_exit+0x0/0x84 tcp_rcv_state_process() ... // (sk_state == TCP_CLOSE_WAIT here) ... /* step 2: check RST bit */ if(th->rst) { tcp_reset(sk); goto discard; } ... --------------------------------- tcp_rcv_state_process tcp_reset tcp_done tcp_set_state(sk, TCP_CLOSE); inet_put_port __inet_put_port inet_sk(sk)->num = 0; sk->sk_shutdown = SHUTDOWN_MASK; 2) After that the process (socket owner) tries to write something to that socket and "inet_autobind" sets a _new_ (which differs from the original!) port number for the socket: Call Trace: [<ffffffff80255a12>] inet_bind_hash+0x33/0x5f [<ffffffff80257180>] inet_csk_get_port+0x216/0x268 [<ffffffff8026bcc9>] inet_autobind+0x22/0x8f [<ffffffff80049140>] inet_sendmsg+0x27/0x57 [<ffffffff8003a9d9>] do_sock_write+0xae/0xea [<ffffffff80226ac7>] sock_writev+0xdc/0xf6 [<ffffffff800680c7>] _spin_lock_irqsave+0x9/0xe [<ffffffff8001fb49>] __pollwait+0x0/0xdd [<ffffffff8008d533>] default_wake_function+0x0/0xe [<ffffffff800a4f10>] autoremove_wake_function+0x0/0x2e [<ffffffff800f0b49>] do_readv_writev+0x163/0x274 [<ffffffff80066538>] thread_return+0x13a/0x174 [<ffffffff800145d8>] tcp_poll+0x0/0x1c9 [<ffffffff800c56d3>] audit_syscall_entry+0x180/0x1b3 [<ffffffff800f0dd0>] sys_writev+0x49/0xe4 [<ffffffff800622dd>] tracesys+0xd5/0xe0 3) sendmsg fails at last with -EPIPE (=> 'write' returns -EPIPE in userspace): F: tcp_sendmsg1 -EPIPE: sk=ffff81000bda00d0, sport=49847, old_state=7, new_state=7, sk_err=0, sk_shutdown=3 Call Trace: [<ffffffff80027557>] tcp_sendmsg+0xcb/0xe87 [<ffffffff80033300>] release_sock+0x10/0xae [<ffffffff8016f20f>] vgacon_cursor+0x0/0x1a7 [<ffffffff8026bd32>] inet_autobind+0x8b/0x8f [<ffffffff8003a9d9>] do_sock_write+0xae/0xea [<ffffffff80226ac7>] sock_writev+0xdc/0xf6 [<ffffffff800680c7>] _spin_lock_irqsave+0x9/0xe [<ffffffff8001fb49>] __pollwait+0x0/0xdd [<ffffffff8008d533>] default_wake_function+0x0/0xe [<ffffffff800a4f10>] autoremove_wake_function+0x0/0x2e [<ffffffff800f0b49>] do_readv_writev+0x163/0x274 [<ffffffff80066538>] thread_return+0x13a/0x174 [<ffffffff800145d8>] tcp_poll+0x0/0x1c9 [<ffffffff800c56d3>] audit_syscall_entry+0x180/0x1b3 [<ffffffff800f0dd0>] sys_writev+0x49/0xe4 [<ffffffff800622dd>] tracesys+0xd5/0xe0 tcp_sendmsg() ... /* Wait for a connection to finish. */ if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { int old_state = sk->sk_state; if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) { if (f_d && (err == -EPIPE)) { printk("F: tcp_sendmsg1 -EPIPE: sk=%p, sport=%u, old_state=%d, new_state=%d, " "sk_err=%d, sk_shutdown=%d\n", sk, ntohs(inet_sk(sk)->sport), old_state, sk->sk_state, sk->sk_err, sk->sk_shutdown); dump_stack(); } goto out_err; } } ... 4) Then the process (socket owner) understands that it's time to close that socket and does that (and thus triggers sending reset packet): Call Trace: ... [<ffffffff80032077>] dev_queue_xmit+0x343/0x3d6 [<ffffffff80034698>] ip_output+0x351/0x384 [<ffffffff80251ae9>] dst_output+0x0/0xe [<ffffffff80036ec6>] ip_queue_xmit+0x567/0x5d2 [<ffffffff80095700>] vprintk+0x21/0x33 [<ffffffff800070f0>] check_poison_obj+0x2e/0x206 [<ffffffff80013587>] poison_obj+0x36/0x45 [<ffffffff8025dea6>] tcp_send_active_reset+0x15/0x14d [<ffffffff80023481>] dbg_redzone1+0x1c/0x25 [<ffffffff8025dea6>] tcp_send_active_reset+0x15/0x14d [<ffffffff8000ca94>] cache_alloc_debugcheck_after+0x189/0x1c8 [<ffffffff80023405>] tcp_transmit_skb+0x764/0x786 [<ffffffff8025df8a>] tcp_send_active_reset+0xf9/0x14d [<ffffffff80258ff1>] tcp_close+0x39a/0x960 [<ffffffff8026be12>] inet_release+0x69/0x80 [<ffffffff80059b31>] sock_release+0x4f/0xcf [<ffffffff80059d4c>] sock_close+0x2c/0x30 [<ffffffff800133c9>] __fput+0xac/0x197 [<ffffffff800252bc>] filp_close+0x59/0x61 [<ffffffff8001eff6>] sys_close+0x85/0xc7 [<ffffffff800622dd>] tracesys+0xd5/0xe0 So, in brief: * a received packet for socket in TCP_CLOSE_WAIT state triggers tcp_reset() which clears inet_sk(sk)->num and put socket into TCP_CLOSE state * an attempt to write to that socket forces inet_autobind() to get a new port (but the write itself fails with -EPIPE) * tcp_close() called for socket in TCP_CLOSE state sends an active reset via socket with newly allocated port This adds an additional check in tcp_close() for already closed sockets. We do not want to send anything to closed sockets. Signed-off-by: Konstantin Khorenko <khorenko@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a3433f35 |
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12-Jun-2010 |
Changli Gao <xiaosuo@gmail.com> |
tcp: unify tcp flag macros unify tcp flag macros: TCPHDR_FIN, TCPHDR_SYN, TCPHDR_RST, TCPHDR_PSH, TCPHDR_ACK, TCPHDR_URG, TCPHDR_ECE and TCPHDR_CWR. TCBCB_FLAG_* are replaced with the corresponding TCPHDR_*. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- include/net/tcp.h | 24 ++++++------- net/ipv4/tcp.c | 8 ++-- net/ipv4/tcp_input.c | 2 - net/ipv4/tcp_output.c | 59 ++++++++++++++++----------------- net/netfilter/nf_conntrack_proto_tcp.c | 32 ++++++----------- net/netfilter/xt_TCPMSS.c | 4 -- 6 files changed, 58 insertions(+), 71 deletions(-) Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d7fd1b57 |
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17-May-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: tcp_md5_hash_skb_data() frag_list handling tcp_md5_hash_skb_data() should handle skb->frag_list, and eventually recurse. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ccbd6a5a |
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14-May-2010 |
Joe Perches <joe@perches.com> |
net: Remove unnecessary semicolons after switch statements Also added an explicit break; to avoid a fallthrough in net/ipv4/tcp_input.c Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
35790c04 |
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16-May-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: fix MD5 (RFC2385) support TCP MD5 support uses percpu data for temporary storage. It currently disables preemption so that same storage cannot be reclaimed by another thread on same cpu. We also have to make sure a softirq handler wont try to use also same context. Various bug reports demonstrated corruptions. Fix is to disable preemption and BH. Reported-by: Bhaskar Dutta <bhaskie@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6c37e5de |
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26-Apr-2010 |
Flavio Leitner <fleitner@redhat.com> |
TCP: avoid to send keepalive probes if receiving data RFC 1122 says the following: ... Keep-alive packets MUST only be sent when no data or acknowledgement packets have been received for the connection within an interval. ... The acknowledgement packet is reseting the keepalive timer but the data packet isn't. This patch fixes it by checking the timestamp of the last received data packet too when the keepalive timer expires. Signed-off-by: Flavio Leitner <fleitner@redhat.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0eae88f3 |
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20-Apr-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: Fix various endianness glitches Sparse can help us find endianness bugs, but we need to make some cleanups to be able to more easily spot real bugs. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
aa395145 |
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20-Apr-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: sk_sleep() helper Define a new function to return the waitqueue of a "struct sock". static inline wait_queue_head_t *sk_sleep(struct sock *sk) { return sk->sk_sleep; } Change all read occurrences of sk_sleep by a call to this function. Needed for a future RCU conversion. sk_sleep wont be a field directly available. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
baff42ab |
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30-Mar-2010 |
Steven J. Magnani <steve@digidescorp.com> |
net: Fix oops from tcp_collapse() when using splice() tcp_read_sock() can have a eat skbs without immediately advancing copied_seq. This can cause a panic in tcp_collapse() if it is called as a result of the recv_actor dropping the socket lock. A userspace program that splices data from a socket to either another socket or to a file can trigger this bug. Signed-off-by: Steven J. Magnani <steve@digidescorp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5a0e3ad6 |
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24-Mar-2010 |
Tejun Heo <tj@kernel.org> |
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
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#
73852e81 |
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15-Mar-2010 |
Steven J. Magnani <steve@digidescorp.com> |
NET_DMA: free skbs periodically Under NET_DMA, data transfer can grind to a halt when userland issues a large read on a socket with a high RCVLOWAT (i.e., 512 KB for both). This appears to be because the NET_DMA design queues up lots of memcpy operations, but doesn't issue or wait for them (and thus free the associated skbs) until it is time for tcp_recvmesg() to return. The socket hangs when its TCP window goes to zero before enough data is available to satisfy the read. Periodically issue asynchronous memcpy operations, and free skbs for ones that have completed, to prevent sockets from going into zero-window mode. Signed-off-by: Steven J. Magnani <steve@digidescorp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b634f875 |
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18-Mar-2010 |
Alexandra Kossovsky <Alexandra.Kossovsky@oktetlabs.ru> |
tcp: Fix OOB POLLIN avoidance. From: Alexandra.Kossovsky@oktetlabs.ru Fixes kernel bugzilla #15541 Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7e380175 |
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17-Feb-2010 |
Andreas Petlund <apetlund@simula.no> |
net: TCP thin dupack This patch enables fast retransmissions after one dupACK for TCP if the stream is identified as thin. This will reduce latencies for thin streams that are not able to trigger fast retransmissions due to high packet interarrival time. This mechanism is only active if enabled by iocontrol or syscontrol and the stream is identified as thin. Signed-off-by: Andreas Petlund <apetlund@simula.no> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
36e31b0a |
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17-Feb-2010 |
Andreas Petlund <apetlund@simula.no> |
net: TCP thin linear timeouts This patch will make TCP use only linear timeouts if the stream is thin. This will help to avoid the very high latencies that thin stream suffer because of exponential backoff. This mechanism is only active if enabled by iocontrol or syscontrol and the stream is identified as thin. A maximum of 6 linear timeouts is tried before exponential backoff is resumed. Signed-off-by: Andreas Petlund <apetlund@simula.no> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7d720c3e |
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16-Feb-2010 |
Tejun Heo <tj@kernel.org> |
percpu: add __percpu sparse annotations to net Add __percpu sparse annotations to net. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. The macro and type tricks around snmp stats make things a bit interesting. DEFINE/DECLARE_SNMP_STAT() macros mark the target field as __percpu and SNMP_UPD_PO_STATS() macro is updated accordingly. All snmp_mib_*() users which used to cast the argument to (void **) are updated to cast it to (void __percpu **). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> Cc: Patrick McHardy <kaber@trash.net> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Vlad Yasevich <vladislav.yasevich@hp.com> Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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#
def87cf4 |
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10-Dec-2009 |
Krishna Kumar <krkumar2@in.ibm.com> |
tcp: Slightly optimize tcp_sendmsg Slightly optimize tcp_sendmsg since NETIF_F_SG is used many times iteratively in the loop. The only other modification is to change: } else if (i == MAX_SKB_FRAGS || (!i && !(sk->sk_route_caps & NETIF_F_SG))) { to: } else if (i == MAX_SKB_FRAGS || !sg) { The reason why this change is correct: this code (other than the MAX_SKB_FRAGS case) executes only due to the else part of: "if (skb_tailroom(skb) > 0) {" - i.e. there was no space in the skb to put the data inline. Hence SG is false is a sufficient condition, and there is no way a fragment can be added to the skb. Changelog: - Added the above explanation for the change Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
afeca340 |
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10-Dec-2009 |
Krishna Kumar <krkumar2@in.ibm.com> |
tcp: Remove unrequired operations in tcp_push() Remove unrequired operations in tcp_push() Changelog: Removed a temporary skb variable from tcp_push() Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3dc78932 |
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08-Dec-2009 |
David S. Miller <davem@davemloft.net> |
tcp: Remove runtime check that can never be true. GCC even warns about it, as reported by Andrew Morton: net/ipv4/tcp.c: In function 'do_tcp_getsockopt': net/ipv4/tcp.c:2544: warning: comparison is always false due to limited range of data type Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e56fb50f |
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02-Dec-2009 |
William Allen Simpson <william.allen.simpson@gmail.com> |
TCPCT part 1e: implement socket option TCP_COOKIE_TRANSACTIONS Provide per socket control of the TCP cookie option and SYN/SYNACK data. This is a straightforward re-implementation of an earlier (year-old) patch that no longer applies cleanly, with permission of the original author (Adam Langley): http://thread.gmane.org/gmane.linux.network/102586 The principle difference is using a TCP option to carry the cookie nonce, instead of a user configured offset in the data. Allocations have been rearranged to avoid requiring GFP_ATOMIC. Requires: net: TCP_MSS_DEFAULT, TCP_MSS_DESIRED TCPCT part 1c: sysctl_tcp_cookie_size, socket option TCP_COOKIE_TRANSACTIONS TCPCT part 1d: define TCP cookie option, extend existing struct's Signed-off-by: William.Allen.Simpson@gmail.com Signed-off-by: David S. Miller <davem@davemloft.net>
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#
da5c78c8 |
|
02-Dec-2009 |
William Allen Simpson <william.allen.simpson@gmail.com> |
TCPCT part 1b: generate Responder Cookie secret Define (missing) hash message size for SHA1. Define hashing size constants specific to TCP cookies. Add new function: tcp_cookie_generator(). Maintain global secret values for tcp_cookie_generator(). This is a significantly revised implementation of earlier (15-year-old) Photuris [RFC-2522] code for the KA9Q cooperative multitasking platform. Linux RCU technique appears to be well-suited to this application, though neither of the circular queue items are freed. These functions will also be used in subsequent patches that implement additional features. Signed-off-by: William.Allen.Simpson@gmail.com Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1fdf475a |
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30-Nov-2009 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: tcp_disconnect() should clear window_clamp NFS can reuse its TCP socket after calling tcp_disconnect(). We noticed window scaling was not negotiated in SYN packet of next connection request. Fix is to clear tp->window_clamp in tcp_disconnect(). Reported-by: Krzysztof Oledzki <ole@ans.pl> Tested-by: Krzysztof Oledzki <ole@ans.pl> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d792c100 |
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13-Nov-2009 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
tcp: provide more information on the tcp receive_queue bugs The addition of rcv_nxt allows to discern whether the skb was out of place or tp->copied. Also catch fancy combination of flags if necessary (sadly we might miss the actual causer flags as it might have already returned). Btw, we perhaps would want to forward copied_seq in somewhere or otherwise we might have some nice loop with WARN stuff within but where to do that safely I don't know at this stage until more is known (but it is not made significantly worse by this patch). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c62f4c45 |
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22-Oct-2009 |
Arjan van de Ven <arjan@linux.intel.com> |
net: use WARN() for the WARN_ON in commit b6b39e8f3fbbb Commit b6b39e8f3fbbb (tcp: Try to catch MSG_PEEK bug) added a printk() to the WARN_ON() that's in tcp.c. This patch changes this combination to WARN(); the advantage of WARN() is that the printk message shows up inside the message, so that kerneloops.org will collect the message. In addition, this gets rid of an extra if() statement. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b6b39e8f |
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19-Oct-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp: Try to catch MSG_PEEK bug This patch tries to print out more information when we hit the MSG_PEEK bug in tcp_recvmsg. It's been around since at least 2005 and it's about time that we finally fix it. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b103cf34 |
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19-Oct-2009 |
Julian Anastasov <ja@ssi.bg> |
tcp: fix TCP_DEFER_ACCEPT retrans calculation Fix TCP_DEFER_ACCEPT conversion between seconds and retransmission to match the TCP SYN-ACK retransmission periods because the time is converted to such retransmissions. The old algorithm selects one more retransmission in some cases. Allow up to 255 retransmissions. Signed-off-by: Julian Anastasov <ja@ssi.bg> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c720c7e8 |
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15-Oct-2009 |
Eric Dumazet <eric.dumazet@gmail.com> |
inet: rename some inet_sock fields In order to have better cache layouts of struct sock (separate zones for rx/tx paths), we need this preliminary patch. Goal is to transfert fields used at lookup time in the first read-mostly cache line (inside struct sock_common) and move sk_refcnt to a separate cache line (only written by rx path) This patch adds inet_ prefix to daddr, rcv_saddr, dport, num, saddr, sport and id fields. This allows a future patch to define these fields as macros, like sk_refcnt, without name clashes. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f373b53b |
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08-Oct-2009 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: replace ehash_size by ehash_mask Storing the mask (size - 1) instead of the size allows fast path to be a bit faster. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
42324c62 |
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01-Oct-2009 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: splice() from tcp to pipe should take into account O_NONBLOCK tcp_splice_read() doesnt take into account socket's O_NONBLOCK flag Before this patch : splice(socket,0,pipe,0,128*1024,SPLICE_F_MOVE); causes a random endless block (if pipe is full) and splice(socket,0,pipe,0,128*1024,SPLICE_F_MOVE | SPLICE_F_NONBLOCK); will return 0 immediately if the TCP buffer is empty. User application has no way to instruct splice() that socket should be in blocking mode but pipe in nonblock more. Many projects cannot use splice(tcp -> pipe) because of this flaw. http://git.samba.org/?p=samba.git;a=history;f=source3/lib/recvfile.c;h=ea0159642137390a0f7e57a123684e6e63e47581;hb=HEAD http://lkml.indiana.edu/hypermail/linux/kernel/0807.2/0687.html Linus introduced SPLICE_F_NONBLOCK in commit 29e350944fdc2dfca102500790d8ad6d6ff4f69d (splice: add SPLICE_F_NONBLOCK flag ) It doesn't make the splice itself necessarily nonblocking (because the actual file descriptors that are spliced from/to may block unless they have the O_NONBLOCK flag set), but it makes the splice pipe operations nonblocking. Linus intention was clear : let SPLICE_F_NONBLOCK control the splice pipe mode only This patch instruct tcp_splice_read() to use the underlying file O_NONBLOCK flag, as other socket operations do. Users will then call : splice(socket,0,pipe,0,128*1024,SPLICE_F_MOVE | SPLICE_F_NONBLOCK ); to block on data coming from socket (if file is in blocking mode), and not block on pipe output (to avoid deadlock) First version of this patch was submitted by Octavian Purdila Reported-by: Volker Lendecke <vl@samba.org> Reported-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4fdb78d3 |
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01-Oct-2009 |
Andrew Morton <akpm@linux-foundation.org> |
net/ipv4/tcp.c: fix min() type mismatch warning net/ipv4/tcp.c: In function 'do_tcp_setsockopt': net/ipv4/tcp.c:2050: warning: comparison of distinct pointer types lacks a cast Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b7058842 |
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30-Sep-2009 |
David S. Miller <davem@davemloft.net> |
net: Make setsockopt() optlen be unsigned. This provides safety against negative optlen at the type level instead of depending upon (sometimes non-trivial) checks against this sprinkled all over the the place, in each and every implementation. Based upon work done by Arjan van de Ven and feedback from Linus Torvalds. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4481374c |
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21-Sep-2009 |
Jan Beulich <JBeulich@novell.com> |
mm: replace various uses of num_physpages by totalram_pages Sizing of memory allocations shouldn't depend on the number of physical pages found in a system, as that generally includes (perhaps a huge amount of) non-RAM pages. The amount of what actually is usable as storage should instead be used as a basis here. Some of the calculations (i.e. those not intending to use high memory) should likely even use (totalram_pages - totalhigh_pages). Signed-off-by: Jan Beulich <jbeulich@novell.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Dave Airlie <airlied@linux.ie> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: "David S. Miller" <davem@davemloft.net> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
0b6a05c1 |
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15-Sep-2009 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
tcp: fix ssthresh u16 leftover It was once upon time so that snd_sthresh was a 16-bit quantity. ...That has not been true for long period of time. I run across some ancient compares which still seem to trust such legacy. Put all that magic into a single place, I hopefully found all of them. Compile tested, though linking of allyesconfig is ridiculous nowadays it seems. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
aa133076 |
|
03-Sep-2009 |
Wu Fengguang <fengguang.wu@intel.com> |
tcp: replace hard coded GFP_KERNEL with sk_allocation This fixed a lockdep warning which appeared when doing stress memory tests over NFS: inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage. page reclaim => nfs_writepage => tcp_sendmsg => lock sk_lock mount_root => nfs_root_data => tcp_close => lock sk_lock => tcp_send_fin => alloc_skb_fclone => page reclaim David raised a concern that if the allocation fails in tcp_send_fin(), and it's GFP_ATOMIC, we are going to yield() (which sleeps) and loop endlessly waiting for the allocation to succeed. But fact is, the original GFP_KERNEL also sleeps. GFP_ATOMIC+yield() looks weird, but it is no worse the implicit sleep inside GFP_KERNEL. Both could loop endlessly under memory pressure. CC: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> CC: David S. Miller <davem@davemloft.net> CC: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
df19a626 |
|
29-Aug-2009 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: keepalive cleanups Introduce keepalive_probes(tp) helper, and use it, like keepalive_time_when(tp) and keepalive_intvl_when(tp) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a57de0b4 |
|
07-Jul-2009 |
Jiri Olsa <jolsa@redhat.com> |
net: adding memory barrier to the poll and receive callbacks Adding memory barrier after the poll_wait function, paired with receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper to wrap the memory barrier. Without the memory barrier, following race can happen. The race fires, when following code paths meet, and the tp->rcv_nxt and __add_wait_queue updates stay in CPU caches. CPU1 CPU2 sys_select receive packet ... ... __add_wait_queue update tp->rcv_nxt ... ... tp->rcv_nxt check sock_def_readable ... { schedule ... if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep) ... } If there was no cache the code would work ok, since the wait_queue and rcv_nxt are opposit to each other. Meaning that once tp->rcv_nxt is updated by CPU2, the CPU1 either already passed the tp->rcv_nxt check and sleeps, or will get the new value for tp->rcv_nxt and will return with new data mask. In both cases the process (CPU1) is being added to the wait queue, so the waitqueue_active (CPU2) call cannot miss and will wake up CPU1. The bad case is when the __add_wait_queue changes done by CPU1 stay in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 will then endup calling schedule and sleep forever if there are no more data on the socket. Calls to poll_wait in following modules were ommited: net/bluetooth/af_bluetooth.c net/irda/af_irda.c net/irda/irnet/irnet_ppp.c net/mac80211/rc80211_pid_debugfs.c net/phonet/socket.c net/rds/af_rds.c net/rfkill/core.c net/sunrpc/cache.c net/sunrpc/rpc_pipe.c net/tipc/socket.c Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6828b92b |
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28-Jun-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp: Do not tack on TSO data to non-TSO packet If a socket starts out on a non-TSO route, and then switches to a TSO route, then we will tack on data to the tail of the tx queue even if it started out life as non-TSO. This is suboptimal because all of it will then be copied and checksummed unnecessarily. This patch fixes this by ensuring that skb->ip_summed is set to CHECKSUM_PARTIAL before appending extra data beyond the MSS. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
91521944 |
|
28-May-2009 |
David S. Miller <davem@davemloft.net> |
tcp: Use SKB queue and list helpers instead of doing it by-hand. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a2a804cd |
|
26-May-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp: Do not check flush when comparing options for GRO There is no need to repeatedly check flush when comparing TCP options for GRO as it will be false 99% of the time where it matters. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a5b1cf28 |
|
26-May-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
gro: Avoid unnecessary comparison after skb_gro_header For the overwhelming majority of cases, skb_gro_header's return value cannot be NULL. Yet we must check it because of its current form. This patch splits it up into multiple functions in order to avoid this. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
30a3ae30 |
|
26-May-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp: Optimise len/mss comparison Instead of checking len > mss || len == 0, we can accomplish both by checking (len - 1) > mss using the unsigned wraparound. At nearly a million times a second, this might just help. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4a9a2968 |
|
26-May-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp: Remove unnecessary window comparisons for GRO The window has already been checked as part of the flag word so there is no need to check it explicitly. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
745898ea |
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26-May-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp: Optimise GRO port comparisons Instead of doing two 16-bit operations for the source/destination ports, we can do one 32-bit operation to take care both. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
77527313 |
|
10-May-2009 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
tcp: fix MSG_PEEK race check Commit 518a09ef11 (tcp: Fix recvmsg MSG_PEEK influence of blocking behavior) lets the loop run longer than the race check did previously expect, so we need to be more careful with this check and consider the work we have been doing. I tried my best to deal with urg hole madness too which happens here: if (!sock_flag(sk, SOCK_URGINLINE)) { ++*seq; ... by using additional offset by one but I certainly have very little interest in testing that part. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Tested-by: Frans Pop <elendil@planet.nl> Tested-by: Ian Zimmermann <itz@buug.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a0a69a01 |
|
17-Apr-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
gro: Fix use after free in tcp_gro_receive After calling skb_gro_receive skb->len can no longer be relied on since if the skb was merged using frags, then its pages will have been removed and the length reduced. This caused tcp_gro_receive to prematurely end merging which resulted in suboptimal performance with ixgbe. The fix is to store skb->len on the stack. Reported-by: Mark Wagner <mwagner@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
377f0a08 |
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31-Mar-2009 |
Rami Rosen <ramirose@gmail.com> |
ipv4: remove unused parameter from tcp_recv_urg(). Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
beedad92 |
|
18-Mar-2009 |
Rami Rosen <ramirose@gmail.com> |
tcp: remove parameter from tcp_recv_urg(). This patch removes an unused parameter (addr_len) from tcp_recv_urg() method in net/ipv4/tcp.c. Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
afece1c6 |
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14-Mar-2009 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
tcp: make sure xmit goal size never becomes zero It's not too likely to happen, would basically require crafted packets (must hit the max guard in tcp_bound_to_half_wnd()). It seems that nothing that bad would happen as there's tcp_mems and congestion window that prevent runaway at some point from hurting all too much (I'm not that sure what all those zero sized segments we would generate do though in write queue). Preventing it regardless is certainly the best way to go. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2a3a041c |
|
14-Mar-2009 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
tcp: cache result of earlier divides when mss-aligning things The results is very unlikely change every so often so we hardly need to divide again after doing that once for a connection. Yet, if divide still becomes necessary we detect that and do the right thing and again settle for non-divide state. Takes the u16 space which was previously taken by the plain xmit_size_goal. This should take care part of the tso vs non-tso difference we found earlier. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0c54b85f |
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14-Mar-2009 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
tcp: simplify tcp_current_mss There's very little need for most of the callsites to get tp->xmit_goal_size updated. That will cost us divide as is, so slice the function in two. Also, the only users of the tp->xmit_goal_size are directly behind tcp_current_mss(), so there's no need to store that variable into tcp_sock at all! The drop of xmit_goal_size currently leaves 16-bit hole and some reorganization would again be necessary to change that (but I'm aiming to fill that hole with u16 xmit_goal_size_segs to cache the results of the remaining divide to get that tso on regression). Bring xmit_goal_size parts into tcp.c Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0d6a775e |
|
27-Feb-2009 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
tcp: in sendmsg/pages open code the real goto target copied was assigned zero right before the goto, so if (copied) cannot ever be true. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
aa6320d3 |
|
08-Feb-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
gro: Optimise TCP packet reception gro: Optimise TCP packet reception As this function can be called more than half a million times for 10GbE, it's important to optimise it as much as we can. This patch uses bit ops to logical ops, as well as open coding memcmp to exploit alignment properties. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
86911732 |
|
29-Jan-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
gro: Avoid copying headers of unmerged packets Unfortunately simplicity isn't always the best. The fraginfo interface turned out to be suboptimal. The problem was quite obvious. For every packet, we have to copy the headers from the frags structure into skb->head, even though for 99% of the packets this part is immediately thrown away after the merge. LRO didn't have this problem because it directly read the headers from the frags structure. This patch attempts to address this by creating an interface that allows GRO to access the headers in the first frag without having to copy it. Because all drivers that use frags place the headers in the first frag this optimisation should be enough. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9fa5fdf2 |
|
26-Jan-2009 |
Dimitris Michailidis <dm@chelsio.com> |
tcp: Fix length tcp_splice_data_recv passes to skb_splice_bits. tcp_splice_data_recv has two lengths to consider: the len parameter it gets from tcp_read_sock, which specifies the amount of data in the skb, and rd_desc->count, which is the amount of data the splice caller still wants. Currently it passes just the latter to skb_splice_bits, which then splices min(rd_desc->count, skb->len - offset) bytes. Most of the time this is fine, except when the skb contains urgent data. In that case len goes only up to the urgent byte and is less than skb->len - offset. By ignoring len tcp_splice_data_recv may a) splice data tcp_read_sock told it not to, b) return to tcp_read_sock a value > len. Now, tcp_read_sock doesn't handle used > len and leaves the socket in a bad state (both sk_receive_queue and copied_seq are bad at that point) resulting in duplicated data and corruption. Fix by passing min(rd_desc->count, len) to skb_splice_bits. Signed-off-by: Dimitris Michailidis <dm@chelsio.com> Acked-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4e704ee3 |
|
14-Jan-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
gso: Ensure that the packet is long enough When we get a GSO packet from an untrusted source, we need to ensure that it is sufficiently long so that we don't end up crashing. Based on discovery and patch by Ian Campbell. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
33966dd0 |
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13-Jan-2009 |
Willy Tarreau <w@1wt.eu> |
tcp: splice as many packets as possible at once As spotted by Willy Tarreau, current splice() from tcp socket to pipe is not optimal. It processes at most one segment per call. This results in low performance and very high overhead due to syscall rate when splicing from interfaces which do not support LRO. Willy provided a patch inside tcp_splice_read(), but a better fix is to let tcp_read_sock() process as many segments as possible, so that tcp_rcv_space_adjust() and tcp_cleanup_rbuf() are called less often. With this change, splice() behaves like tcp_recvmsg(), being able to consume many skbs in one system call. With typical 1460 bytes of payload per frame, that means splice(SPLICE_F_NONBLOCK) can return 16*1460 = 23360 bytes. Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
684f2176 |
|
08-Jan-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp6: Add GRO support This patch adds GRO support for TCP over IPv6. The code is exactly the same as the IPv4 version except for the pseudo-header checksum computation. Note that I've removed the unused tcphdr argument from tcp_v6_check rather than invent a bogus value for GRO. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f67b4599 |
|
06-Jan-2009 |
Dan Williams <dan.j.williams@intel.com> |
net_dma: convert to dma_find_channel Use the general-purpose channel allocation provided by dmaengine. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
6f49a57a |
|
06-Jan-2009 |
Dan Williams <dan.j.williams@intel.com> |
dmaengine: up-level reference counting to the module level Simply, if a client wants any dmaengine channel then prevent all dmaengine modules from being removed. Once the clients are done re-enable module removal. Why?, beyond reducing complication: 1/ Tracking reference counts per-transaction in an efficient manner, as is currently done, requires a complicated scheme to avoid cache-line bouncing effects. 2/ Per-transaction ref-counting gives the false impression that a dma-driver can be gracefully removed ahead of its user (net, md, or dma-slave) 3/ None of the in-tree dma-drivers talk to hot pluggable hardware, but if such an engine were built one day we still would not need to notify clients of remove events. The driver can simply return NULL to a ->prep() request, something that is much easier for a client to handle. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
|
#
7945cc64 |
|
05-Jan-2009 |
David S. Miller <davem@davemloft.net> |
tcp: Kill extraneous SPLICE_F_NONBLOCK checks. In splice TCP receive, the SPLICE_F_NONBLOCK flag is used to compute the "timeo" value. So checking it again inside of the main receive loop to trigger -EAGAIN processing is entirely unnecessary. Noticed by Jarek P. and Lennert Buytenhek. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4f7d54f5 |
|
05-Jan-2009 |
Lennert Buytenhek <buytenh@marvell.com> |
tcp: don't mask EOF and socket errors on nonblocking splice receive Currently, setting SPLICE_F_NONBLOCK on splice from a TCP socket results in masking of EOF (RDHUP) and error conditions on the socket by an -EAGAIN return. Move the NONBLOCK check in tcp_splice_read() to be after the EOF and error checks to fix this. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b530256d |
|
04-Jan-2009 |
Herbert Xu <herbert@gondor.apana.org.au> |
gro: Use gso_size to store MSS In order to allow GRO packets without frag_list at all, we need to store the MSS in the packet itself. The obvious place is gso_size. The only thing to watch out for is if the packet ends up not being GRO then we need to clear gso_size before pushing the packet into the stack. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
eb4dea58 |
|
30-Dec-2008 |
Herbert Xu <herbert@gondor.apana.org.au> |
net: Fix percpu counters deadlock When we converted the protocol atomic counters such as the orphan count and the total socket count deadlocks were introduced due to the mismatch in BH status of the spots that used the percpu counter operations. Based on the diagnosis and patch by Peter Zijlstra, this patch fixes these issues by disabling BH where we may be in process context. Reported-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Tested-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
bf296b12 |
|
16-Dec-2008 |
Herbert Xu <herbert@gondor.apana.org.au> |
tcp: Add GRO support This patch adds the TCP-specific portion of GRO. The criterion for merging is extremely strict (the TCP header must match exactly apart from the checksum) so as to allow refragmentation. Otherwise this is pretty much identical to LRO, except that we support the merging of ECN packets. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
dd24c001 |
|
25-Nov-2008 |
Eric Dumazet <dada1@cosmosbay.com> |
net: Use a percpu_counter for orphan_count Instead of using one atomic_t per protocol, use a percpu_counter for "orphan_count", to reduce cache line contention on heavy duty network servers. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
1748376b |
|
25-Nov-2008 |
Eric Dumazet <dada1@cosmosbay.com> |
net: Use a percpu_counter for sockets_allocated Instead of using one atomic_t per protocol, use a percpu_counter for "sockets_allocated", to reduce cache line contention on heavy duty network servers. Note : We revert commit (248969ae31e1b3276fc4399d67ce29a5d81e6fd9 net: af_unix can make unix_nr_socks visbile in /proc), since it is not anymore used after sock_prot_inuse_add() addition Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3ab5aee7 |
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16-Nov-2008 |
Eric Dumazet <dada1@cosmosbay.com> |
net: Convert TCP & DCCP hash tables to use RCU / hlist_nulls RCU was added to UDP lookups, using a fast infrastructure : - sockets kmem_cache use SLAB_DESTROY_BY_RCU and dont pay the price of call_rcu() at freeing time. - hlist_nulls permits to use few memory barriers. This patch uses same infrastructure for TCP/DCCP established and timewait sockets. Thanks to SLAB_DESTROY_BY_RCU, no slowdown for applications using short lived TCP connections. A followup patch, converting rwlocks to spinlocks will even speedup this case. __inet_lookup_established() is pretty fast now we dont have to dirty a contended cache line (read_lock/read_unlock) Only established and timewait hashtable are converted to RCU (bind table and listen table are still using traditional locking) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
518a09ef |
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05-Nov-2008 |
David S. Miller <davem@davemloft.net> |
tcp: Fix recvmsg MSG_PEEK influence of blocking behavior. Vito Caputo noticed that tcp_recvmsg() returns immediately from partial reads when MSG_PEEK is used. In particular, this means that SO_RCVLOWAT is not respected. Simply remove the test. And this matches the behavior of several other systems, including BSD. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5a5f3a8d |
|
03-Nov-2008 |
Jianjun Kong <jianjun@zeuux.org> |
net: clean up net/ipv4/ipip.c raw.c tcp.c tcp_minisocks.c tcp_yeah.c xfrm4_policy.c Signed-off-by: Jianjun Kong <jianjun@zeuux.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
33f5f57e |
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07-Oct-2008 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
tcp: kill pointless urg_mode It all started from me noticing that this urgent check in tcp_clean_rtx_queue is unnecessarily inside the loop. Then I took a longer look to it and found out that the users of urg_mode can trivially do without, well almost, there was one gotcha. Bonus: those funny people who use urg with >= 2^31 write_seq - snd_una could now rejoice too (that's the only purpose for the between being there, otherwise a simple compare would have done the thing). Not that I assume that the rest of the tcp code happily lives with such mind-boggling numbers :-). Alas, it turned out to be impossible to set wmem to such numbers anyway, yes I really tried a big sendfile after setting some wmem but nothing happened :-). ...Tcp_wmem is int and so is sk_sndbuf... So I hacked a bit variable to long and found out that it seems to work... :-) Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c57943a1 |
|
07-Oct-2008 |
Peter Zijlstra <a.p.zijlstra@chello.nl> |
net: wrap sk->sk_backlog_rcv() Wrap calling sk->sk_backlog_rcv() in a function. This will allow extending the generic sk_backlog_rcv behaviour. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c7004482 |
|
06-Oct-2008 |
David S. Miller <davem@davemloft.net> |
tcp: Respect SO_RCVLOWAT in tcp_poll(). Based upon a report by Vito Caputo. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
547b792c |
|
25-Jul-2008 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
net: convert BUG_TRAP to generic WARN_ON Removes legacy reinvent-the-wheel type thing. The generic machinery integrates much better to automated debugging aids such as kerneloops.org (and others), and is unambiguous due to better naming. Non-intuively BUG_TRAP() is actually equal to WARN_ON() rather than BUG_ON() though some might actually be promoted to BUG_ON() but I left that to future. I could make at least one BUILD_BUG_ON conversion. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
49a72dfb |
|
19-Jul-2008 |
Adam Langley <agl@imperialviolet.org> |
tcp: Fix MD5 signatures for non-linear skbs Currently, the MD5 code assumes that the SKBs are linear and, in the case that they aren't, happily goes off and hashes off the end of the SKB and into random memory. Reported by Stephen Hemminger in [1]. Advice thanks to Stephen and Evgeniy Polyakov. Also includes a couple of missed route_caps from Stephen's patch in [2]. [1] http://marc.info/?l=linux-netdev&m=121445989106145&w=2 [2] http://marc.info/?l=linux-netdev&m=121459157816964&w=2 Signed-off-by: Adam Langley <agl@imperialviolet.org> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
57ef42d5 |
|
18-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
mib: put tcp statistics on struct net Proc temporary uses stats from init_net. BTW, TCP_XXX_STATS are beautiful (w/o do { } while (0) facing) again :) Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ed88098e |
|
16-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
mib: add net to NET_ADD_STATS_USER Done with NET_XXX_STATS macros :) To be continued... Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
6f67c817 |
|
16-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
mib: add net to NET_INC_STATS_USER Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
de0744af |
|
16-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
mib: add net to NET_INC_STATS_BH Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
4e673444 |
|
16-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
mib: add net to NET_INC_STATS Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
5c52ba17 |
|
16-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
sock: add net to prot->enter_memory_pressure callback The tcp_enter_memory_pressure calls NET_INC_STATS, but doesn't have where to get the net from. I decided to add a sk argument, not the net itself, only to factor all the required sock_net(sk) calls inside the enter_memory_pressure callback itself. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
74688e48 |
|
16-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
mib: add net to TCP_DEC_STATS Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
63231bdd |
|
16-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
mib: add net to TCP_INC_STATS_BH Same as before - the sock is always there to get the net from, but there are also some places with the net already saved on the stack. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
81cc8a75 |
|
16-Jul-2008 |
Pavel Emelyanov <xemul@openvz.org> |
mib: add net to TCP_INC_STATS Fortunately (almost) all the TCP code has a sock to get the net from :) Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
70efce27 |
|
16-Jul-2008 |
Will Newton <will.newton@gmail.com> |
net/ipv4/tcp.c: Fix use of PULLHUP instead of POLLHUP in comments. Change PULLHUP to POLLHUP in tcp_poll comments and clean up another comment for grammar and coding style. Signed-off-by: Will Newton <will.newton@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
374e7b59 |
|
03-Jul-2008 |
Octavian Purdila <opurdila@ixiacom.com> |
tcp: fix a size_t < 0 comparison in tcp_read_sock <used> should be of type int (not size_t) since recv_actor can return negative values and it is also used in a < 0 comparison. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
81b23b4a |
|
03-Jul-2008 |
Andrew Morton <akpm@linux-foundation.org> |
tcp: net/ipv4/tcp.c needs linux/scatterlist.h alpha: net/ipv4/tcp.c: In function 'tcp_calc_md5_hash': net/ipv4/tcp.c:2479: error: implicit declaration of function 'sg_init_table' net/ipv4/tcp.c:2482: error: implicit declaration of function 'sg_set_buf' net/ipv4/tcp.c:2507: error: implicit declaration of function 'sg_mark_end' Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
57413ebc |
|
27-Jun-2008 |
Miquel van Smoorenburg <miquels@cistron.nl> |
tcp: calculate tcp_mem based on low memory instead of all memory The tcp_mem array which contains limits on the total amount of memory used by TCP sockets is calculated based on nr_all_pages. On a 32 bits x86 system, we should base this on the number of lowmem pages. Signed-off-by: Miquel van Smoorenburg <miquels@cistron.nl> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ec0a1966 |
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12-Jun-2008 |
David S. Miller <davem@davemloft.net> |
tcp: Revert 'process defer accept as established' changes. This reverts two changesets, ec3c0982a2dd1e671bad8e9d26c28dcba0039d87 ("[TCP]: TCP_DEFER_ACCEPT updates - process as established") and the follow-on bug fix 9ae27e0adbf471c7a6b80102e38e1d5a346b3b38 ("tcp: Fix slab corruption with ipv6 and tcp6fuzz"). This change causes several problems, first reported by Ingo Molnar as a distcc-over-loopback regression where connections were getting stuck. Ilpo Järvinen first spotted the locking problems. The new function added by this code, tcp_defer_accept_check(), only has the child socket locked, yet it is modifying state of the parent listening socket. Fixing that is non-trivial at best, because we can't simply just grab the parent listening socket lock at this point, because it would create an ABBA deadlock. The normal ordering is parent listening socket --> child socket, but this code path would require the reverse lock ordering. Next is a problem noticed by Vitaliy Gusev, he noted: ---------------------------------------- >--- a/net/ipv4/tcp_timer.c >+++ b/net/ipv4/tcp_timer.c >@@ -481,6 +481,11 @@ static void tcp_keepalive_timer (unsigned long data) > goto death; > } > >+ if (tp->defer_tcp_accept.request && sk->sk_state == TCP_ESTABLISHED) { >+ tcp_send_active_reset(sk, GFP_ATOMIC); >+ goto death; Here socket sk is not attached to listening socket's request queue. tcp_done() will not call inet_csk_destroy_sock() (and tcp_v4_destroy_sock() which should release this sk) as socket is not DEAD. Therefore socket sk will be lost for freeing. ---------------------------------------- Finally, Alexey Kuznetsov argues that there might not even be any real value or advantage to these new semantics even if we fix all of the bugs: ---------------------------------------- Hiding from accept() sockets with only out-of-order data only is the only thing which is impossible with old approach. Is this really so valuable? My opinion: no, this is nothing but a new loophole to consume memory without control. ---------------------------------------- So revert this thing for now. Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
0b040829 |
|
10-Jun-2008 |
Adrian Bunk <bunk@kernel.org> |
net: remove CVS keywords This patch removes CVS keywords that weren't updated for a long time from comments. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8d26d76d |
|
16-Apr-2008 |
YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> |
tcp md5sig: Share most of hash calcucaltion bits between IPv4 and IPv6. We can share most part of the hash calculation code because the only difference between IPv4 and IPv6 is their pseudo headers. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
|
#
293ad604 |
|
04-Jun-2008 |
Octavian Purdila <opurdila@ixiacom.com> |
tcp: Fix for race due to temporary drop of the socket lock in skb_splice_bits. skb_splice_bits temporary drops the socket lock while iterating over the socket queue in order to break a reverse locking condition which happens with sendfile. This, however, opens a window of opportunity for tcp_collapse() to aggregate skbs and thus potentially free the current skb used in skb_splice_bits and tcp_read_sock. This patch fixes the problem by (re-)getting the same "logical skb" after the lock has been temporary dropped. Based on idea and initial patch from Evgeniy Polyakov. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
1f29b058 |
|
21-Apr-2008 |
Satoru SATOH <satoru.satoh@gmail.com> |
tcp: Trivial fix to correct function name in a comment in net/ipv4/tcp.c This is a trivial fix to correct function name in a comment in net/ipv4/tcp.c. Signed-off-by: Satoru SATOH <satoru.satoh@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
69d15067 |
|
22-Mar-2008 |
Herbert Xu <herbert@gondor.apana.org.au> |
[TCP]: Let skbs grow over a page on fast peers While testing the virtio-net driver on KVM with TSO I noticed that TSO performance with a 1500 MTU is significantly worse compared to the performance of non-TSO with a 16436 MTU. The packet dump shows that most of the packets sent are smaller than a page. Looking at the code this actually is quite obvious as it always stop extending the packet if it's the first packet yet to be sent and if it's larger than the MSS. Since each extension is bound by the page size, this means that (given a 1500 MTU) we're very unlikely to construct packets greater than a page, provided that the receiver and the path is fast enough so that packets can always be sent immediately. The fix is also quite obvious. The push calls inside the loop is just an optimisation so that we don't end up doing all the sending at the end of the loop. Therefore there is no specific reason why it has to do so at MSS boundaries. For TSO, the most natural extension of this optimisation is to do the pushing once the skb exceeds the TSO size goal. This is what the patch does and testing with KVM shows that the TSO performance with a 1500 MTU easily surpasses that of a 16436 MTU and indeed the packet sizes sent are generally larger than 16436. I don't see any obvious downsides for slower peers or connections, but it would be prudent to test this extensively to ensure that those cases don't regress. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ec3c0982 |
|
21-Mar-2008 |
Patrick McManus <mcmanus@ducksong.com> |
[TCP]: TCP_DEFER_ACCEPT updates - process as established Change TCP_DEFER_ACCEPT implementation so that it transitions a connection to ESTABLISHED after handshake is complete instead of leaving it in SYN-RECV until some data arrvies. Place connection in accept queue when first data packet arrives from slow path. Benefits: - established connection is now reset if it never makes it to the accept queue - diagnostic state of established matches with the packet traces showing completed handshake - TCP_DEFER_ACCEPT timeouts are expressed in seconds and can now be enforced with reasonable accuracy instead of rounding up to next exponential back-off of syn-ack retry. Signed-off-by: Patrick McManus <mcmanus@ducksong.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ab1e0a13 |
|
03-Feb-2008 |
Arnaldo Carvalho de Melo <acme@redhat.com> |
[SOCK] proto: Add hashinfo member to struct proto This way we can remove TCP and DCCP specific versions of sk->sk_prot->get_port: both v4 and v6 use inet_csk_get_port sk->sk_prot->hash: inet_hash is directly used, only v6 need a specific version to deal with mapped sockets sk->sk_prot->unhash: both v4 and v6 use inet_hash directly struct inet_connection_sock_af_ops also gets a new member, bind_conflict, so that inet_csk_get_port can find the per family routine. Now only the lookup routines receive as a parameter a struct inet_hashtable. With this we further reuse code, reducing the difference among INET transport protocols. Eventually work has to be done on UDP and SCTP to make them share this infrastructure and get as a bonus inet_diag interfaces so that iproute can be used with these protocols. net-2.6/net/ipv4/inet_hashtables.c: struct proto | +8 struct inet_connection_sock_af_ops | +8 2 structs changed __inet_hash_nolisten | +18 __inet_hash | -210 inet_put_port | +8 inet_bind_bucket_create | +1 __inet_hash_connect | -8 5 functions changed, 27 bytes added, 218 bytes removed, diff: -191 net-2.6/net/core/sock.c: proto_seq_show | +3 1 function changed, 3 bytes added, diff: +3 net-2.6/net/ipv4/inet_connection_sock.c: inet_csk_get_port | +15 1 function changed, 15 bytes added, diff: +15 net-2.6/net/ipv4/tcp.c: tcp_set_state | -7 1 function changed, 7 bytes removed, diff: -7 net-2.6/net/ipv4/tcp_ipv4.c: tcp_v4_get_port | -31 tcp_v4_hash | -48 tcp_v4_destroy_sock | -7 tcp_v4_syn_recv_sock | -2 tcp_unhash | -179 5 functions changed, 267 bytes removed, diff: -267 net-2.6/net/ipv6/inet6_hashtables.c: __inet6_hash | +8 1 function changed, 8 bytes added, diff: +8 net-2.6/net/ipv4/inet_hashtables.c: inet_unhash | +190 inet_hash | +242 2 functions changed, 432 bytes added, diff: +432 vmlinux: 16 functions changed, 485 bytes added, 492 bytes removed, diff: -7 /home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c: tcp_v6_get_port | -31 tcp_v6_hash | -7 tcp_v6_syn_recv_sock | -9 3 functions changed, 47 bytes removed, diff: -47 /home/acme/git/net-2.6/net/dccp/proto.c: dccp_destroy_sock | -7 dccp_unhash | -179 dccp_hash | -49 dccp_set_state | -7 dccp_done | +1 5 functions changed, 1 bytes added, 242 bytes removed, diff: -241 /home/acme/git/net-2.6/net/dccp/ipv4.c: dccp_v4_get_port | -31 dccp_v4_request_recv_sock | -2 2 functions changed, 33 bytes removed, diff: -33 /home/acme/git/net-2.6/net/dccp/ipv6.c: dccp_v6_get_port | -31 dccp_v6_hash | -7 dccp_v6_request_recv_sock | +5 3 functions changed, 5 bytes added, 38 bytes removed, diff: -33 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
490d5046 |
|
12-Jan-2008 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
[TCP]: Uninline tcp_set_state net/ipv4/tcp.c: tcp_close_state | -226 tcp_done | -145 tcp_close | -564 tcp_disconnect | -141 4 functions changed, 1076 bytes removed, diff: -1076 net/ipv4/tcp_input.c: tcp_fin | -86 tcp_rcv_state_process | -164 2 functions changed, 250 bytes removed, diff: -250 net/ipv4/tcp_ipv4.c: tcp_v4_connect | -209 1 function changed, 209 bytes removed, diff: -209 net/ipv4/arp.c: arp_ignore | +5 1 function changed, 5 bytes added, diff: +5 net/ipv6/tcp_ipv6.c: tcp_v6_connect | -158 1 function changed, 158 bytes removed, diff: -158 net/sunrpc/xprtsock.c: xs_sendpages | -2 1 function changed, 2 bytes removed, diff: -2 net/dccp/ccids/ccid3.c: ccid3_update_send_interval | +7 1 function changed, 7 bytes added, diff: +7 net/ipv4/tcp.c: tcp_set_state | +238 1 function changed, 238 bytes added, diff: +238 built-in.o: 12 functions changed, 250 bytes added, 1695 bytes removed, diff: -1445 I've no explanation why some unrelated changes seem to occur consistently as well (arp_ignore, ccid3_update_send_interval; I checked the arp_ignore asm and it seems to be due to some reordered of operation order causing some extra opcodes to be generated). Still, the benefits are pretty obvious from the codiff's results. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
4828e7f4 |
|
31-Dec-2007 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
[TCP]: Remove TCPCB_URG & TCPCB_AT_TAIL as unnecessary The snd_up check should be enough. I suspect this has been there to provide a minor optimization in clean_rtx_queue which used to have a small if (!->sacked) block which could skip snd_up check among the other work. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
3ab224be |
|
31-Dec-2007 |
Hideo Aoki <haoki@redhat.com> |
[NET] CORE: Introducing new memory accounting interface. This patch introduces new memory accounting functions for each network protocol. Most of them are renamed from memory accounting functions for stream protocols. At the same time, some stream memory accounting functions are removed since other functions do same thing. Renaming: sk_stream_free_skb() -> sk_wmem_free_skb() __sk_stream_mem_reclaim() -> __sk_mem_reclaim() sk_stream_mem_reclaim() -> sk_mem_reclaim() sk_stream_mem_schedule -> __sk_mem_schedule() sk_stream_pages() -> sk_mem_pages() sk_stream_rmem_schedule() -> sk_rmem_schedule() sk_stream_wmem_schedule() -> sk_wmem_schedule() sk_charge_skb() -> sk_mem_charge() Removeing sk_stream_rfree(): consolidates into sock_rfree() sk_stream_set_owner_r(): consolidates into skb_set_owner_r() sk_stream_mem_schedule() The following functions are added. sk_has_account(): check if the protocol supports accounting sk_mem_uncharge(): do the opposite of sk_mem_charge() In addition, to achieve consolidation, updating sk_wmem_queued is removed from sk_mem_charge(). Next, to consolidate memory accounting functions, this patch adds memory accounting calls to network core functions. Moreover, present memory accounting call is renamed to new accounting call. Finally we replace present memory accounting calls with new interface in TCP and SCTP. Signed-off-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Hideo Aoki <haoki@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
1f9e636e |
|
11-Dec-2007 |
Pavel Emelyanov <xemul@openvz.org> |
[TCP]: Use BUILD_BUG_ON for tcp_skb_cb size checking The sizeof(struct tcp_skb_cb) should not be less than the sizeof(skb->cb). This is checked in net/ipv4/tcp.c, but this check can be made more gracefully. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
df97c708 |
|
29-Nov-2007 |
Pavel Emelyanov <xemul@openvz.org> |
[NET]: Eliminate unused argument from sk_stream_alloc_pskb The 3rd argument is always zero (according to grep :) Eliminate it and merge the function with sk_stream_alloc_skb. This saves 44 more bytes, and together with the previous patch we have: add/remove: 1/0 grow/shrink: 0/8 up/down: 183/-751 (-568) function old new delta sk_stream_alloc_skb - 183 +183 ip_rt_init 529 525 -4 arp_ignore 112 107 -5 __inet_lookup_listener 284 274 -10 tcp_sendmsg 2583 2481 -102 tcp_sendpage 1449 1300 -149 tso_fragment 417 258 -159 tcp_fragment 1149 988 -161 __tcp_push_pending_frames 1998 1837 -161 Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
f561d0f2 |
|
29-Nov-2007 |
Pavel Emelyanov <xemul@openvz.org> |
[NET]: Uninline the sk_stream_alloc_pskb This function seems too big for inlining. Indeed, it saves half-a-kilo when uninlined: add/remove: 1/0 grow/shrink: 0/7 up/down: 195/-719 (-524) function old new delta sk_stream_alloc_pskb - 195 +195 ip_rt_init 529 525 -4 __inet_lookup_listener 284 274 -10 tcp_sendmsg 2583 2486 -97 tcp_sendpage 1449 1305 -144 tso_fragment 417 267 -150 tcp_fragment 1149 992 -157 __tcp_push_pending_frames 1998 1841 -157 Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
6ff7751d |
|
07-Nov-2007 |
Adrian Bunk <bunk@kernel.org> |
[TCP]: Make tcp_splice_data_recv() static. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
9c55e01c |
|
07-Nov-2007 |
Jens Axboe <jens.axboe@oracle.com> |
[TCP]: Splice receive support. Support for network splice receive. Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
230140cf |
|
07-Nov-2007 |
Eric Dumazet <dada1@cosmosbay.com> |
[INET]: Remove per bucket rwlock in tcp/dccp ehash table. As done two years ago on IP route cache table (commit 22c047ccbc68fa8f3fa57f0e8f906479a062c426) , we can avoid using one lock per hash bucket for the huge TCP/DCCP hash tables. On a typical x86_64 platform, this saves about 2MB or 4MB of ram, for litle performance differences. (we hit a different cache line for the rwlock, but then the bucket cache line have a better sharing factor among cpus, since we dirty it less often). For netstat or ss commands that want a full scan of hash table, we perform fewer memory accesses. Using a 'small' table of hashed rwlocks should be more than enough to provide correct SMP concurrency between different buckets, without using too much memory. Sizing of this table depends on num_possible_cpus() and various CONFIG settings. This patch provides some locking abstraction that may ease a future work using a different model for TCP/DCCP table. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
0ccfe618 |
|
30-Oct-2007 |
Jean Delvare <jdelvare@suse.de> |
[TCP]: Saner thash_entries default with much memory. On systems with a very large amount of memory, the heuristics in alloc_large_system_hash() result in a very large TCP established hash table: 16 millions of entries for a 128 GB ia64 system. This makes reading from /proc/net/tcp pretty slow (well over a second) and as a result netstat is slow on these machines. I know that /proc/net/tcp is deprecated in favor of tcp_diag, however at the moment netstat only knows of the former. I am skeptical that such a large TCP established hash is often needed. Just because a system has a lot of memory doesn't imply that it will have several millions of concurrent TCP connections. Thus I believe that we should put an arbitrary high limit to the size of the TCP established hash by default. Users who really need a bigger hash can always use the thash_entries boot parameter to get more. I propose 2 millions of entries as the arbitrary high limit. This makes /proc/net/tcp reasonably fast on the system in question (0.2 s) while being still large enough for me to be confident that network performance won't suffer. This is just one way to limit the hash size, there are others; I am not familiar enough with the TCP code to decide which is best. Thus, I would welcome the proposals of alternatives. [ 2 million is still too large, thus I've modified the limit in the change to be '512 * 1024'. -DaveM ] Signed-off-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ba25f9dc |
|
19-Oct-2007 |
Pavel Emelyanov <xemul@openvz.org> |
Use helpers to obtain task pid in printks The task_struct->pid member is going to be deprecated, so start using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in the kernel. The first thing to start with is the pid, printed to dmesg - in this case we may safely use task_pid_nr(). Besides, printks produce more (much more) than a half of all the explicit pid usage. [akpm@linux-foundation.org: git-drm went and changed lots of stuff] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Dave Airlie <airlied@linux.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
5ee3afba |
|
18-Sep-2007 |
Rick Jones <rick.jones2@hp.com> |
[TCP]: Return useful listenq info in tcp_info and INET_DIAG_INFO. Return some useful information such as the maximum listen backlog and the current listen backlog in the tcp_info structure and INET_DIAG_INFO. Signed-off-by: Rick Jones <rick.jones2@hp.com> Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
172589cc |
|
28-Aug-2007 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
[NET]: DIV_ROUND_UP cleanup (part two) Hopefully captured all single statement cases under net/. I'm not too sure if there is some policy about #includes that are "guaranteed" (ie., in the current tree) to be available through some other #included header, so I just added linux/kernel.h to each changed file that didn't #include it previously. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
e60402d0 |
|
09-Aug-2007 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
[TCP]: Move sack_ok access to obviously named funcs & cleanup Previously code had IsReno/IsFack defined as macros that were local to tcp_input.c though sack_ok field has user elsewhere too for the same purpose. This changes them to static inlines as preferred according the current coding style and unifies the access to sack_ok across multiple files. Magic bitops of sack_ok for FACK and DSACK are also abstracted to functions with appropriate names. Note: - One sack_ok = 1 remains but that's self explanary, i.e., it enables sack - Couple of !IsReno cases are changed to tcp_is_sack - There were no users for IsDSack => I dropped it Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
3516ffb0 |
|
02-Aug-2007 |
David S. Miller <davem@sunset.davemloft.net> |
[TCP]: Invoke tcp_sendmsg() directly, do not use inet_sendmsg(). As discovered by Evegniy Polyakov, if we try to sendmsg after a connection reset, we can do incredibly stupid things. The core issue is that inet_sendmsg() tries to autobind the socket, but we should never do that for TCP. Instead we should just go straight into TCP's sendmsg() code which will do all of the necessary state and pending socket error checks. TCP's sendpage already directly vectors to tcp_sendpage(), so this merely brings sendmsg() in line with that. Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
20c2df83 |
|
19-Jul-2007 |
Paul Mundt <lethal@linux-sh.org> |
mm: Remove slab destructors from kmem_cache_create(). Slab destructors were no longer supported after Christoph's c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been BUGs for both slab and slub, and slob never supported them either. This rips out support for the dtor pointer from kmem_cache_create() completely and fixes up every single callsite in the kernel (there were about 224, not including the slab allocator definitions themselves, or the documentation references). Signed-off-by: Paul Mundt <lethal@linux-sh.org>
|
#
e00c5d8b |
|
08-Mar-2007 |
Andrew Morton <akpm@osdl.org> |
I/OAT: warning fix net/ipv4/tcp.c: In function 'tcp_recvmsg': net/ipv4/tcp.c:1111: warning: unused variable 'available' Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Chris Leech <christopher.leech@intel.com>
|
#
2b1244a4 |
|
08-Mar-2007 |
Chris Leech <christopher.leech@intel.com> |
I/OAT: Only offload copies for TCP when there will be a context switch The performance wins come with having the DMA copy engine doing the copies in parallel with the context switch. If there is enough data ready on the socket at recv time just use a regular copy. Signed-off-by: Chris Leech <christopher.leech@intel.com>
|
#
ddb61a57 |
|
24-Jun-2007 |
Jens Axboe <jens.axboe@oracle.com> |
[TCP] tcp_read_sock: Allow recv_actor() return return negative error value. tcp_read_sock() currently assumes that the recv_actor() only returns number of bytes copied. For network splice receive, we may have to return an error in some cases. So allow the actor to return a negative error value. Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
3f196eb5 |
|
31-May-2007 |
Mark Glines <mark@glines.org> |
[TCP]: Use default 32768-61000 outgoing port range in all cases. This diff changes the default port range used for outgoing connections, from "use 32768-61000 in most cases, but use N-4999 on small boxes (where N is a multiple of 1024, depending on just *how* small the box is)" to just "use 32768-61000 in all cases". I don't believe there are any drawbacks to this change, and it keeps outgoing connection ports farther away from the mess of IANA-registered ports. Signed-off-by: Mark Glines <mark@glines.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
e4fd5da3 |
|
29-May-2007 |
Pavel Emelianov <xemul@openvz.org> |
[TCP]: Consolidate checking for tcp orphan count being too big. tcp_out_of_resources() and tcp_close() perform the same checking of number of orphan sockets. Move this code into common place. Signed-off-by: Pavel Emelianov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
e63340ae |
|
08-May-2007 |
Randy Dunlap <randy.dunlap@oracle.com> |
header cleaning: don't include smp_lock.h when not used Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
b40b4f79 |
|
03-May-2007 |
Srinivas Aji <Aji_Srinivas@emc.com> |
[TCP]: zero out rx_opt in tcp_disconnect() When the server drops its connection, NFS client reconnects using the same socket after disconnecting. If the new connection's SYN,ACK doesn't contain the TCP timestamp option and the old connection's did, tp->tcp_header_len is recomputed assuming no timestamp header but tp->rx_opt.tstamp_ok remains set. Then tcp_build_and_update_options() adds in a timestamp option past the end of the allocated TCP header, overwriting TCP data, or when the data is in skb_shinfo(skb)->frags[], overwriting skb_shinfo(skb) causing a crash soon after. (The issue was debugged from such a crash.) Similarly, wscale_ok and sack_ok also get set based on the SYN,ACK packet but not reset on disconnect, since they are zeroed out at initialization. The patch zeroes out the entire tp->rx_opt struct in tcp_disconnect() to avoid this sort of problem. Signed-off-by: Srinivas Aji <Aji_Srinivas@emc.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
65bb723c |
|
28-Apr-2007 |
Gerrit Renker <gerrit@erg.abdn.ac.uk> |
[TCP]: Update references in two old comments This updates references to drafts in comments which must be about 10 years old. Internet draft draft-ietf-tcpimpl-prob-03.txt expired in 1998 and was replaced by RFC 2525 in March 1999. Section 3.10 of the draft maps almost identically into section 2.17 of RFC 2525: both are entitled "Failure to RST on close with data pending", the differences in text body amount to a typo and minor sentence change. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
9e412ba7 |
|
20-Apr-2007 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
[TCP]: Sed magic converts func(sk, tp, ...) -> func(sk, ...) This is (mostly) automated change using magic: sed -e '/struct sock \*sk/ N' -e '/struct sock \*sk/ N' -e '/struct sock \*sk/ N' -e '/struct sock \*sk/ N' -e 's|struct sock \*sk,[\n\t ]*struct tcp_sock \*tp\([^{]*\n{\n\)| struct sock \*sk\1\tstruct tcp_sock *tp = tcp_sk(sk);\n|g' -e 's|struct sock \*sk, struct tcp_sock \*tp| struct sock \*sk|g' -e 's|sk, tp\([^-]\)|sk\1|g' Fixed four unused variable (tp) warnings that were introduced. In addition, manually added newlines after local variables and tweaked function arguments positioning. $ gcc --version gcc (GCC) 4.1.1 20060525 (Red Hat 4.1.1-1) ... $ codiff -fV built-in.o.old built-in.o.new net/ipv4/route.c: rt_cache_flush | +14 1 function changed, 14 bytes added net/ipv4/tcp.c: tcp_setsockopt | -5 tcp_sendpage | -25 tcp_sendmsg | -16 3 functions changed, 46 bytes removed net/ipv4/tcp_input.c: tcp_try_undo_recovery | +3 tcp_try_undo_dsack | +2 tcp_mark_head_lost | -12 tcp_ack | -15 tcp_event_data_recv | -32 tcp_rcv_state_process | -10 tcp_rcv_established | +1 7 functions changed, 6 bytes added, 69 bytes removed, diff: -63 net/ipv4/tcp_output.c: update_send_head | -9 tcp_transmit_skb | +19 tcp_cwnd_validate | +1 tcp_write_wakeup | -17 __tcp_push_pending_frames | -25 tcp_push_one | -8 tcp_send_fin | -4 7 functions changed, 20 bytes added, 63 bytes removed, diff: -43 built-in.o.new: 18 functions changed, 40 bytes added, 178 bytes removed, diff: -138 Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
4ac02bab |
|
20-Apr-2007 |
Andi Kleen <ak@linux.intel.com> |
[TCP]: Uninline tcp_done(). The function is quite big and has several call sites and nothing to collapse by compiler optimization on inlining. Besides it's nicer to read in a in .c file. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
3ff50b79 |
|
20-Apr-2007 |
Stephen Hemminger <shemminger@linux-foundation.org> |
[NET]: cleanup extra semicolons Spring cleaning time... There seems to be a lot of places in the network code that have extra bogus semicolons after conditionals. Most commonly is a bogus semicolon after: switch() { } Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
4103f8cd |
|
27-Mar-2007 |
Eric Dumazet <dada1@cosmosbay.com> |
[TCP]: tcp_memory_pressure and tcp_socket are__read_mostly candidates tcp_memory_pressure and tcp_socket currently share a cache line with tcp_memory_allocated, tcp_sockets_allocated. (Very hot cache line) It makes sense to declare these variables as __read_mostly, to avoid false sharing on SMP. ffffffff8081d9c0 B tcp_orphan_count ffffffff8081d9c4 B tcp_memory_allocated ffffffff8081d9c8 B tcp_sockets_allocated ffffffff8081d9cc B tcp_memory_pressure ffffffff8081d9d0 b tcp_md5sig_users ffffffff8081d9d8 b tcp_md5sig_pool ffffffff8081d9e0 b warntime.31570 ffffffff8081d9e8 b tcp_socket Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
27a884dc |
|
19-Apr-2007 |
Arnaldo Carvalho de Melo <acme@redhat.com> |
[SK_BUFF]: Convert skb->tail to sk_buff_data_t So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes on 64bit architectures, allowing us to combine the 4 bytes hole left by the layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4 64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN... :-) Many calculations that previously required that skb->{transport,network, mac}_header be first converted to a pointer now can be done directly, being meaningful as offsets or pointers. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
9c70220b |
|
25-Apr-2007 |
Arnaldo Carvalho de Melo <acme@redhat.com> |
[SK_BUFF]: Introduce skb_transport_header(skb) For the places where we need a pointer to the transport header, it is still legal to touch skb->h.raw directly if just adding to, subtracting from or setting it to another layer header. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
aa8223c7 |
|
10-Apr-2007 |
Arnaldo Carvalho de Melo <acme@redhat.com> |
[SK_BUFF]: Introduce tcp_hdr(), remove skb->h.th Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
fe067e8a |
|
07-Mar-2007 |
David S. Miller <davem@sunset.davemloft.net> |
[TCP]: Abstract out all write queue operations. This allows the write queue implementation to be changed, for example, to one which allows fast interval searching. Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
53cdcc04 |
|
16-Mar-2007 |
John Heffner <jheffner@psc.edu> |
[TCP]: Fix tcp_mem[] initialization. Change tcp_mem initialization function. The fraction of total memory is now a continuous function of memory size, and independent of page size. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
2c4f6219 |
|
21-Feb-2007 |
David S. Miller <davem@sunset.davemloft.net> |
[TCP]: Fix MD5 signature pool locking. The locking calls assumed that these code paths were only invoked in software interrupt context, but that isn't true. Therefore we need to use spin_{lock,unlock}_bh() throughout. Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
e905a9ed |
|
09-Feb-2007 |
YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> |
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
dbca9b275 |
|
08-Feb-2007 |
Eric Dumazet <dada1@cosmosbay.com> |
[NET]: change layout of ehash table ehash table layout is currently this one : First half of this table is used by sockets not in TIME_WAIT state Second half of it is used by sockets in TIME_WAIT state. This is non optimal because of for a given hash or socket, the two chain heads are located in separate cache lines. Moreover the locks of the second half are never used. If instead of this halving, we use two list heads in inet_ehash_bucket instead of only one, we probably can avoid one cache miss, and reduce ram usage, particularly if sizeof(rwlock_t) is big (various CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_LOCK_ALLOC settings). So we still halves the table but we keep together related chains to speedup lookups and socket state change. In this patch I did not try to align struct inet_ehash_bucket, but a future patch could try to make this structure have a convenient size (a power of two or a multiple of L1_CACHE_SIZE). I guess rwlock will just vanish as soon as RCU is plugged into ehash :) , so maybe we dont need to scratch our heads to align the bucket... Note : In case struct inet_ehash_bucket is not a power of two, we could probably change alloc_large_system_hash() (in case it use __get_free_pages()) to free the unused space. It currently allocates a big zone, but the last quarter of it could be freed. Again, this should be a temporary 'problem'. Patch tested on ipv4 tcp only, but should be OK for IPV6 and DCCP. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
6931ba7c |
|
13-Dec-2006 |
David S. Miller <davem@sunset.davemloft.net> |
[TCP]: Fix oops caused by __tcp_put_md5sig_pool() It should call tcp_free_md5sig_pool() not __tcp_free_md5sig_pool() so that it does proper refcounting. Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
f5b99bcd |
|
30-Nov-2006 |
Adrian Bunk <bunk@stusta.de> |
[NET]: Possible cleanups. This patch contains the following possible cleanups: - make the following needlessly global functions statis: - ipv4/tcp.c: __tcp_alloc_md5sig_pool() - ipv4/tcp_ipv4.c: tcp_v4_reqsk_md5_lookup() - ipv4/udplite.c: udplite_rcv() - ipv4/udplite.c: udplite_err() - make the following needlessly global structs static: - ipv4/tcp_ipv4.c: tcp_request_sock_ipv4_ops - ipv4/tcp_ipv4.c: tcp_sock_ipv4_specific - ipv6/tcp_ipv6.c: tcp_request_sock_ipv6_ops - net/ipv{4,6}/udplite.c: remove inline's from static functions (gcc should know best when to inline them) Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
352d4800 |
|
17-Nov-2006 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[TCP]: Tidy up skb_entail Heck, it even saves us some few bytes: [acme@newtoy net-2.6.20]$ codiff -f /tmp/tcp.o.before ../OUTPUT/qemu/net-2.6.20/net/ipv4/tcp.o /pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp.c: tcp_sendpage | -7 tcp_sendmsg | -5 2 functions changed, 12 bytes removed [acme@newtoy net-2.6.20]$ Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
|
#
d3bc23e7 |
|
14-Nov-2006 |
Al Viro <viro@zeniv.linux.org.uk> |
[NET]: Annotate callers of csum_fold() in net/* Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
cfb6eeb4 |
|
14-Nov-2006 |
YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> |
[TCP]: MD5 Signature Option (RFC2385) support. Based on implementation by Rick Payne. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
52bf376c |
|
14-Nov-2006 |
John Heffner <jheffner@psc.edu> |
[TCP]: Fix up sysctl_tcp_mem initialization. Fix up tcp_mem initial settings to take into account the size of the hash entries (different on SMP and non-SMP systems). Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
9e950efa |
|
07-Nov-2006 |
John Heffner <jheffner@psc.edu> |
[TCP]: Don't use highmem in tcp hash size calculation. This patch removes consideration of high memory when determining TCP hash table sizes. Taking into account high memory results in tcp_mem values that are too large. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
1ef9696c |
|
19-Sep-2006 |
Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> |
[TCP]: Send ACKs each 2nd received segment. It does not affect either mss-sized connections (obviously) or connections controlled by Nagle (because there is only one small segment in flight). The idea is to record the fact that a small segment arrives on a connection, where one small segment has already been received and still not-ACKed. In this case ACK is forced after tcp_recvmsg() drains receive buffer. In other words, it is a "soft" each-2nd-segment ACK, which is enough to preserve ACK clock even when ABC is enabled. Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
e5d679f33 |
|
26-Aug-2006 |
Alexey Dobriyan <adobriyan@gmail.com> |
[NET]: Use SLAB_PANIC Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ab32ea5d |
|
22-Sep-2006 |
Brian Haley <brian.haley@hp.com> |
[NET/IPV4/IPV6]: Change some sysctl variables to __read_mostly Change net/core, ipv4 and ipv6 sysctl variables to __read_mostly. Couldn't actually measure any performance increase while testing (.3% I consider noise), but seems like the right thing to do. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
84fa7933 |
|
29-Aug-2006 |
Patrick McHardy <kaber@trash.net> |
[NET]: Replace CHECKSUM_HW by CHECKSUM_PARTIAL/CHECKSUM_COMPLETE Replace CHECKSUM_HW by CHECKSUM_PARTIAL (for outgoing packets, whose checksum still needs to be completed) and CHECKSUM_COMPLETE (for incoming packets, device supplied full checksum). Patch originally from Herbert Xu, updated by myself for 2.6.18-rc3. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
29bbd72d |
|
02-Aug-2006 |
Alexey Dobriyan <adobriyan@gmail.com> |
[NET]: Fix more per-cpu typos Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
52499afe |
|
31-Jul-2006 |
David S. Miller <davem@sunset.davemloft.net> |
[TCP]: Process linger2 timeout consistently. Based upon guidance from Alexey Kuznetsov. When linger2 is active, we check to see if the fin_wait2 timeout is longer than the timewait. If it is, we schedule the keepalive timer for the difference between the timewait timeout and the fin_wait2 timeout. When this orphan socket is seen by tcp_keepalive_timer() it will try to transform this fin_wait2 socket into a fin_wait2 mini-socket, again if linger2 is active. Not all paths were setting this initial keepalive timer correctly. The tcp input path was doing it correctly, but tcp_close() wasn't, potentially making the socket linger longer than it really needs to. Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
bbcf467d |
|
03-Jul-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[NET]: Verify gso_type too in gso_segment We don't want nasty Xen guests to pass a TCPv6 packet in with gso_type set to TCPv4 or even UDP (or a packet that's both TCP and UDP). Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bcd76111 |
|
30-Jun-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[NET]: Generalise TSO-specific bits from skb_setup_caps This patch generalises the TSO-specific bits from sk_setup_caps by adding the sk_gso_type member to struct sock. This makes sk_setup_caps generic so that it can be used by TCPv6 or UFO. The only catch is that whoever uses this must provide a GSO implementation for their protocol which I think is a fair deal :) For now UFO continues to live without a GSO implementation which is OK since it doesn't use the sock caps field at the moment. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
adcfc7d0 |
|
30-Jun-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[IPV6]: Added GSO support for TCPv6 This patch adds GSO support for IPv6 and TCPv6. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3820c3f3 |
|
29-Jun-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[TCP]: Reset gso_segs if packet is dodgy I wasn't paranoid enough in verifying GSO information. A bogus gso_segs could upset drivers as much as a bogus header would. Let's reset it in the per-protocol gso_segment functions. I didn't verify gso_size because that can be verified by the source of the dodgy packets. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6ab3d562 |
|
30-Jun-2006 |
Jörn Engel <joern@wohnheim.fh-wedel.de> |
Remove obsolete #include <linux/config.h> Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
|
#
576a30eb |
|
27-Jun-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[NET]: Added GSO header verification When GSO packets come from an untrusted source (e.g., a Xen guest domain), we need to verify the header integrity before passing it to the hardware. Since the first step in GSO is to verify the header, we can reuse that code by adding a new bit to gso_type: SKB_GSO_DODGY. Packets with this bit set can only be fed directly to devices with the corresponding bit NETIF_F_GSO_ROBUST. If the device doesn't have that bit, then the skb is fed to the GSO engine which will allow the packet to be sent to the hardware if it passes the header check. This patch changes the sg flag to a full features flag. The same method can be used to implement TSO ECN support. We simply have to mark packets with CWR set with SKB_GSO_ECN so that only hardware with a corresponding NETIF_F_TSO_ECN can accept them. The GSO engine can either fully segment the packet, or segment the first MTU and pass the rest to the hardware for further segmentation. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
0718bcc0 |
|
26-Jun-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[NET]: Fix CHECKSUM_HW GSO problems. Fix checksum problems in the GSO code path for CHECKSUM_HW packets. The ipv4 TCP pseudo header checksum has to be adjusted for GSO segmented packets. The adjustment is needed because the length field in the pseudo-header changes. However, because we have the inequality oldlen > newlen, we know that delta = (u16)~oldlen + newlen is still a 16-bit quantity. This also means that htonl(delta) + th->check still fits in 32 bits. Therefore we don't have to use csum_add on this operations. This is based on a patch by Michael Chan <mchan@broadcom.com>. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f4c50d99 |
|
22-Jun-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[NET]: Add software TSOv4 This patch adds the GSO implementation for IPv4 TCP. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
7967168c |
|
22-Jun-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[NET]: Merge TSO/UFO fields in sk_buff Having separate fields in sk_buff for TSO/UFO (tso_size/ufo_size) is not going to scale if we add any more segmentation methods (e.g., DCCP). So let's merge them. They were used to tell the protocol of a packet. This function has been subsumed by the new gso_type field. This is essentially a set of netdev feature bits (shifted by 16 bits) that are required to process a specific skb. As such it's easy to tell whether a given device can process a GSO skb: you just have to and the gso_type field and the netdev's features field. I've made gso_type a conjunction. The idea is that you have a base type (e.g., SKB_GSO_TCPV4) that can be modified further to support new features. For example, if we add a hardware TSO type that supports ECN, they would declare NETIF_F_TSO | NETIF_F_TSO_ECN. All TSO packets with CWR set would have a gso_type of SKB_GSO_TCPV4 | SKB_GSO_TCPV4_ECN while all other TSO packets would be SKB_GSO_TCPV4. This means that only the CWR packets need to be emulated in software. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
8648b305 |
|
17-Jun-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[NET]: Add NETIF_F_GEN_CSUM and NETIF_F_ALL_CSUM The current stack treats NETIF_F_HW_CSUM and NETIF_F_NO_CSUM identically so we test for them in quite a few places. For the sake of brevity, I'm adding the macro NETIF_F_GEN_CSUM for these two. We also test the disjunct of NETIF_F_IP_CSUM and the other two in various places, for that purpose I've added NETIF_F_ALL_CSUM. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
1a2449a8 |
|
23-May-2006 |
Chris Leech <christopher.leech@intel.com> |
[I/OAT]: TCP recv offload to I/OAT Locks down user pages and sets up for DMA in tcp_recvmsg, then calls dma_async_try_early_copy in tcp_v4_do_rcv Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
624d1164 |
|
23-May-2006 |
Chris Leech <christopher.leech@intel.com> |
[I/OAT]: Make sk_eat_skb I/OAT aware. Add an extra argument to sk_eat_skb, and make it move early copied packets to the async_wait_queue instead of freeing them. Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
0e4b4992 |
|
23-May-2006 |
Chris Leech <christopher.leech@intel.com> |
[I/OAT]: Rename cleanup_rbuf to tcp_cleanup_rbuf and make non-static Needed to be able to call tcp_cleanup_rbuf in tcp_input.c for I/OAT Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
75c2d907 |
|
04-May-2006 |
Herbert Xu <herbert@gondor.apana.org.au> |
[TCP]: Fix sock_orphan dead lock Calling sock_orphan inside bh_lock_sock in tcp_close can lead to dead locks. For example, the inet_diag code holds sk_callback_lock without disabling BH. If an inbound packet arrives during that admittedly tiny window, it will cause a dead lock on bh_lock_sock. Another possible path would be through sock_wfree if the network device driver frees the tx skb in process context with BH enabled. We can fix this by moving sock_orphan out of bh_lock_sock. The tricky bit is to work out when we need to destroy the socket ourselves and when it has already been destroyed by someone else. By moving sock_orphan before the release_sock we can solve this problem. This is because as long as we own the socket lock its state cannot change. So we simply record the socket state before the release_sock and then check the state again after we regain the socket lock. If the socket state has transitioned to TCP_CLOSE in the time being, we know that the socket has been destroyed. Otherwise the socket is still ours to keep. Note that I've also moved the increment on the orphan count forward. This may look like a problem as we're increasing it even if the socket is just about to be destroyed where it'll be decreased again. However, this simply enlarges a window that already exists. This also changes the orphan count test by one. Considering what the orphan count is meant to do this is no big deal. This problem was discoverd by Ingo Molnar using his lock validator. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
f348d70a |
|
25-Mar-2006 |
Davide Libenzi <davidel@xmailserver.org> |
[PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications Implement the half-closed devices notifiation, by adding a new POLLRDHUP (and its alias EPOLLRDHUP) bit to the existing poll/select sets. Since the existing POLLHUP handling, that does not report correctly half-closed devices, was feared to be changed, this implementation leaves the current POLLHUP reporting unchanged and simply add a new bit that is set in the few places where it makes sense. The same thing was discussed and conceptually agreed quite some time ago: http://lkml.org/lkml/2003/7/12/116 Since this new event bit is added to the existing Linux poll infrastruture, even the existing poll/select system calls will be able to use it. As far as the existing POLLHUP handling, the patch leaves it as is. The pollrdhup-2.6.16.rc5-0.10.diff defines the POLLRDHUP for all the existing archs and sets the bit in the six relevant files. The other attached diff is the simple change required to sys/epoll.h to add the EPOLLRDHUP definition. There is "a stupid program" to test POLLRDHUP delivery here: http://www.xmailserver.org/pollrdhup-test.c It tests poll(2), but since the delivery is same epoll(2) will work equally. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Michael Kerrisk <mtk-manpages@gmx.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
b8059ead |
|
25-Mar-2006 |
David S. Miller <davem@sunset.davemloft.net> |
[TCP]: Mark tcp_*mem[] __read_mostly. Suggested by Stephen Hemminger. Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
7b4f4b5e |
|
25-Mar-2006 |
John Heffner <jheffner@psc.edu> |
[TCP]: Set default max buffers from memory pool size This patch sets the maximum TCP buffer sizes (available to automatic buffer tuning, not to setsockopt) based on the TCP memory pool size. The maximum sndbuf and rcvbuf each will be up to 4 MB, but no more than 1/128 of the memory pressure threshold. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
543d9cfe |
|
20-Mar-2006 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[NET]: Identation & other cleanups related to compat_[gs]etsockopt cset No code changes, just tidying up, in some cases moving EXPORT_SYMBOLs to just after the function exported, etc. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
dec73ff0 |
|
20-Mar-2006 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[ICSK] compat: Introduce inet_csk_compat_[gs]etsockopt Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
3fdadf7d |
|
20-Mar-2006 |
Dmitry Mishin <dim@openvz.org> |
[NET]: {get|set}sockopt compatibility layer This patch extends {get|set}sockopt compatibility layer in order to move protocol specific parts to their place and avoid huge universal net/compat.c file in the future. Signed-off-by: Dmitry Mishin <dim@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
d83d8461 |
|
14-Dec-2005 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[IP_SOCKGLUE]: Remove most of the tcp specific calls As DCCP needs to be called in the same spots. Now we have a member in inet_sock (is_icsk), set at sock creation time from struct inet_protosw->flags (if INET_PROTOSW_ICSK is set, like for TCP and DCCP) to see if a struct sock instance is a inet_connection_sock for places like the ones in ip_sockglue.c (v4 and v6) where we previously were looking if sk_type was SOCK_STREAM, that is insufficient because we now use the same code for DCCP, that has sk_type SOCK_DCCP. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
8292a17a |
|
14-Dec-2005 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[ICSK]: Rename struct tcp_func to struct inet_connection_sock_af_ops And move it to struct inet_connection_sock. DCCP will use it in the upcoming changesets. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
9b5b5cff |
|
29-Nov-2005 |
Arjan van de Ven <arjan@infradead.org> |
[NET]: Add const markers to various variables. the patch below marks various variables const in net/; the goal is to move them to the .rodata section so that they can't false-share cachelines with things that get written to, as well as potentially helping gcc a bit with optimisations. (these were found using a gcc patch to warn about such variables) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
18955cfc |
|
29-Nov-2005 |
Mike Stroyan <mike.stroyan@hp.com> |
[IPV4] tcp/route: Another look at hash table sizes The tcp_ehash hash table gets too big on systems with really big memory. It is worse on systems with pages larger than 4KB. It wastes memory that could be better used. It also makes the netstat command slow because reading /proc/net/tcp and /proc/net/tcp6 needs to go through the full hash table. The default value should not be larger for larger page sizes. It seems that the effect of page size is an unintended error dating back a long time. I also wonder if the default value really should be a larger fraction of memory for systems with more memory. While systems with really big ram can afford more space for hash tables, it is not clear to me that they benefit from increasing the allocation ratio for this table. The amount of memory allocated is determined by net/ipv4/tcp.c:tcp_init and mm/page_alloc.c:alloc_large_system_hash. tcp_init calls alloc_large_system_hash passing parameters- bucketsize=sizeof(struct tcp_ehash_bucket) numentries=thash_entries scale=(num_physpages >= 128 * 1024) ? (25-PAGE_SHIFT) : (27-PAGE_SHIFT) limit=0 On i386, PAGE_SHIFT is 12 for a page size of 4K On ia64, PAGE_SHIFT defaults to 14 for a page size of 16K The num_physpages test above makes the allocation take a larger fraction of the total memory on systems with larger memory. The threshold size for a i386 system is 512MB. For an ia64 system with 16KB pages the threshold is 2GB. For smaller memory systems- On i386, scale = (27 - 12) = 15 On ia64, scale = (27 - 14) = 13 For larger memory systems- On i386, scale = (25 - 12) = 13 On ia64, scale = (25 - 14) = 11 For the rest of this discussion, I'll just track the larger memory case. The default behavior has numentries=thash_entries=0, so the allocated size is determined by either scale or by the default limit of 1/16 of total memory. In alloc_large_system_hash- | numentries = (flags & HASH_HIGHMEM) ? nr_all_pages : nr_kernel_pages; | numentries += (1UL << (20 - PAGE_SHIFT)) - 1; | numentries >>= 20 - PAGE_SHIFT; | numentries <<= 20 - PAGE_SHIFT; At this point, numentries is pages for all of memory, rounded up to the nearest megabyte boundary. | /* limit to 1 bucket per 2^scale bytes of low memory */ | if (scale > PAGE_SHIFT) | numentries >>= (scale - PAGE_SHIFT); | else | numentries <<= (PAGE_SHIFT - scale); On i386, numentries >>= (13 - 12), so numentries is 1/8196 of bytes of total memory. On ia64, numentries <<= (14 - 11), so numentries is 1/2048 of bytes of total memory. | log2qty = long_log2(numentries); | | do { | size = bucketsize << log2qty; bucketsize is 16, so size is 16 times numentries, rounded down to a power of two. On i386, size is 1/512 of bytes of total memory. On ia64, size is 1/128 of bytes of total memory. For smaller systems the results are On i386, size is 1/2048 of bytes of total memory. On ia64, size is 1/512 of bytes of total memory. The large page effect can be removed by just replacing the use of PAGE_SHIFT with a constant of 12 in the calls to alloc_large_system_hash. That makes them more like the other uses of that function from fs/inode.c and fs/dcache.c Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
caa20d9a |
|
10-Nov-2005 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: spelling fixes Minor spelling fixes for TCP code. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
9772efb9 |
|
10-Nov-2005 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: Appropriate Byte Count support This is an updated version of the RFC3465 ABC patch originally for Linux 2.6.11-rc4 by Yee-Ting Li. ABC is a way of counting bytes ack'd rather than packets when updating congestion control. The orignal ABC described in the RFC applied to a Reno style algorithm. For advanced congestion control there is little change after leaving slow start. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
6df71634 |
|
03-Nov-2005 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP/DCCP]: Randomize port selection This patch randomizes the port selected on bind() for connections to help with possible security attacks. It should also be faster in most cases because there is no need for a global lock. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
|
#
fb5f5e6e |
|
05-Sep-2005 |
Herbert Xu <herbert@gondor.apana.org.au> |
[TCP]: Fix TCP_OFF() bug check introduced by previous change. The TCP_OFF assignment at the bottom of that if block can indeed set TCP_OFF without setting TCP_PAGE. Since there is not much to be gained from avoiding this situation, we might as well just zap the offset. The following patch should fix it. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ef015786 |
|
01-Sep-2005 |
Herbert Xu <herbert@gondor.apana.org.au> |
[TCP]: Fix sk_forward_alloc underflow in tcp_sendmsg I've finally found a potential cause of the sk_forward_alloc underflows that people have been reporting sporadically. When tcp_sendmsg tacks on extra bits to an existing TCP_PAGE we don't check sk_forward_alloc even though a large amount of time may have elapsed since we allocated the page. In the mean time someone could've come along and liberated packets and reclaimed sk_forward_alloc memory. This patch makes tcp_sendmsg check sk_forward_alloc every time as we do in do_tcp_sendpages. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
d80d99d6 |
|
01-Sep-2005 |
Herbert Xu <herbert@gondor.apana.org.au> |
[NET]: Add sk_stream_wmem_schedule This patch introduces sk_stream_wmem_schedule as a short-hand for the sk_forward_alloc checking on egress. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ba89966c |
|
26-Aug-2005 |
Eric Dumazet <dada1@cosmosbay.com> |
[NET]: use __read_mostly on kmem_cache_t , DEFINE_SNMP_STAT pointers This patch puts mostly read only data in the right section (read_mostly), to help sharing of these data between CPUS without memory ping pongs. On one of my production machine, tcp_statistics was sitting in a heavily modified cache line, so *every* SNMP update had to force a reload. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
dc40c7bc |
|
23-Aug-2005 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[ICSK]: Generalise tcp_listen_poll Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
6687e988 |
|
10-Aug-2005 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[ICSK]: Move TCP congestion avoidance members to icsk This changeset basically moves tcp_sk()->{ca_ops,ca_state,etc} to inet_csk(), minimal renaming/moving done in this changeset to ease review. Most of it is just changes of struct tcp_sock * to struct sock * parameters. With this we move to a state closer to two interesting goals: 1. Generalisation of net/ipv4/tcp_diag.c, becoming inet_diag.c, being used for any INET transport protocol that has struct inet_hashinfo and are derived from struct inet_connection_sock. Keeps the userspace API, that will just not display DCCP sockets, while newer versions of tools can support DCCP. 2. INET generic transport pluggable Congestion Avoidance infrastructure, using the current TCP CA infrastructure with DCCP. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
295ff7ed |
|
09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[TIMEWAIT]: Introduce inet_timewait_death_row That groups all of the tables and variables associated to the TCP timewait schedulling/recycling/killing code, that now can be isolated from the TCP specific code and used by other transport protocols, such as DCCP. Next changeset will move this code to net/ipv4/inet_timewait_sock.c Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
a019d6fe |
|
09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[ICSK]: Move generalised functions from tcp to inet_connection_sock This also improves reqsk_queue_prune and renames it to inet_csk_reqsk_queue_prune, as it deals with both inet_connection_sock and inet_request_sock objects, not just with request_sock ones thus belonging to inet_request_sock. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
295f7324 |
|
09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[ICSK]: Introduce reqsk_queue_prune from code in tcp_synack_timer With this we're very close to getting all of the current TCP refactorings in my dccp-2.6 tree merged, next changeset will export some functions needed by the current DCCP code and then dccp-2.6.git will be born! Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
0a5578cf |
|
09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[ICSK]: Generalise tcp_listen_{start,stop} This also moved inet_iif from tcp to inet_hashtables.h, as it is needed by the inet_lookup callers, perhaps this needs a bit of polishing, but for now seems fine. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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3f421baa |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[NET]: Just move the inet_connection_sock function from tcp sources Completing the previous changeset, this also generalises tcp_v4_synq_add, renaming it to inet_csk_reqsk_queue_hash_add, already geing used in the DCCP tree, which I plan to merge RSN. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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463c84b9 |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[NET]: Introduce inet_connection_sock This creates struct inet_connection_sock, moving members out of struct tcp_sock that are shareable with other INET connection oriented protocols, such as DCCP, that in my private tree already uses most of these members. The functions that operate on these members were renamed, using a inet_csk_ prefix while not being moved yet to a new file, so as to ease the review of these changes. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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8feaf0c0 |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[INET]: Generalise tcp_tw_bucket, aka TIME_WAIT sockets This paves the way to generalise the rest of the sock ID lookup routines and saves some bytes in TCPv4 TIME_WAIT sockets on distro kernels (where IPv6 is always built as a module): [root@qemu ~]# grep tw_sock /proc/slabinfo tw_sock_TCPv6 0 0 128 31 1 tw_sock_TCP 0 0 96 41 1 [root@qemu ~]# Now if a protocol wants to use the TIME_WAIT generic infrastructure it only has to set the sk_prot->twsk_obj_size field with the size of its inet_timewait_sock derived sock and proto_register will create sk_prot->twsk_slab, for now its only for INET sockets, but we can introduce timewait_sock later if some non INET transport protocolo wants to use this stuff. Next changesets will take advantage of this new infrastructure to generalise even more TCP code. [acme@toy net-2.6.14]$ grep built-in /tmp/before.size /tmp/after.size /tmp/before.size: 188646 11764 5068 205478 322a6 net/ipv4/built-in.o /tmp/after.size: 188144 11764 5068 204976 320b0 net/ipv4/built-in.o [acme@toy net-2.6.14]$ Tested with both IPv4 & IPv6 (::1 (localhost) & ::ffff:172.20.0.1 (qemu host)). Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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6e04e021 |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[INET]: Move tcp_port_rover to inet_hashinfo Also expose all of the tcp_hashinfo members, i.e. killing those tcp_ehash, etc macros, this will more clearly expose already generic functions and some that need just a bit of work to become generic, as we'll see in the upcoming changesets. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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2d8c4ce5 |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[INET]: Generalise tcp_bind_hash & tcp_inherit_port This required moving tcp_bucket_cachep to inet_hashinfo. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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a55ebcc4 |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[INET]: Move bind_hash from tcp_sk to inet_sk This should really be in a inet_connection_sock, but I'm leaving it for a later optimization, when some more fields common to INET transport protocols now in tcp_sk or inet_sk will be chunked out into inet_connection_sock, for now its better to concentrate on getting the changes in the core merged to leave the DCCP tree with only DCCP specific code. Next changesets will take advantage of this move to generalise things like tcp_bind_hash, tcp_put_port, tcp_inherit_port, making the later receive a inet_hashinfo parameter, and even __tcp_tw_hashdance, etc in the future, when tcp_tw_bucket gets transformed into the struct timewait_sock hierarchy. tcp_destroy_sock also is eligible as soon as tcp_orphan_count gets moved to sk_prot. A cascade of incremental changes will ultimately make the tcp_lookup functions be fully generic. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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0f7ff927 |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[INET]: Just rename the TCP hashtable functions/structs to inet_ This is to break down the complexity of the series of patches, making it very clear that this one just does: 1. renames tcp_ prefixed hashtable functions and data structures that were already mostly generic to inet_ to share it with DCCP and other INET transport protocols. 2. Removes not used functions (__tb_head & tb_head) 3. Removes some leftover prototypes in the headers (tcp_bucket_unlock & tcp_v4_build_header) Next changesets will move tcp_sk(sk)->bind_hash to inet_sock so that we can make functions such as tcp_inherit_port, __tcp_inherit_port, tcp_v4_get_port, __tcp_put_port, generic and get others like tcp_destroy_sock closer to generic (tcp_orphan_count will go to sk->sk_prot to allow this). Eventually most of these functions will be used passing the transport protocol inet_hashinfo structure. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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e6848976 |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[NET]: Cleanup INET_REFCNT_DEBUG code Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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83e3609e |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[REQSK]: Move the syn_table destroy from tcp_listen_stop to reqsk_queue_destroy Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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8728b834 |
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09-Aug-2005 |
David S. Miller <davem@davemloft.net> |
[NET]: Kill skb->list Remove the "list" member of struct sk_buff, as it is entirely redundant. All SKB list removal callers know which list the SKB is on, so storing this in sk_buff does nothing other than taking up some space. Two tricky bits were SCTP, which I took care of, and two ATM drivers which Francois Romieu <romieu@fr.zoreil.com> fixed up. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
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89ebd197 |
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23-Aug-2005 |
David S. Miller <davem@davemloft.net> |
[TCP]: Unconditionally clear TCP_NAGLE_PUSH in skb_entail(). Intention of this bit is to force pushing of the existing send queue when TCP_CORK or TCP_NODELAY state changes via setsockopt(). But it's easy to create a situation where the bit never clears. For example, if the send queue starts empty: 1) set TCP_NODELAY 2) clear TCP_NODELAY 3) set TCP_CORK 4) do small write() The current code will leave TCP_NAGLE_PUSH set after that sequence. Unconditionally clearing the bit when new data is added via skb_entail() solves the problem. Signed-off-by: David S. Miller <davem@davemloft.net>
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b03efcfb |
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08-Jul-2005 |
David S. Miller <davem@davemloft.net> |
[NET]: Transform skb_queue_len() binary tests into skb_queue_empty() This is part of the grand scheme to eliminate the qlen member of skb_queue_head, and subsequently remove the 'list' member of sk_buff. Most users of skb_queue_len() want to know if the queue is empty or not, and that's trivially done with skb_queue_empty() which doesn't use the skb_queue_head->qlen member and instead uses the queue list emptyness as the test. Signed-off-by: David S. Miller <davem@davemloft.net>
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c1b4a7e6 |
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05-Jul-2005 |
David S. Miller <davem@davemloft.net> |
[TCP]: Move to new TSO segmenting scheme. Make TSO segment transmit size decisions at send time not earlier. The basic scheme is that we try to build as large a TSO frame as possible when pulling in the user data, but the size of the TSO frame output to the card is determined at transmit time. This is guided by tp->xmit_size_goal. It is always set to a multiple of MSS and tells sendmsg/sendpage how large an SKB to try and build. Later, tcp_write_xmit() and tcp_push_one() chop up the packet if necessary and conditions warrant. These routines can also decide to "defer" in order to wait for more ACKs to arrive and thus allow larger TSO frames to be emitted. A general observation is that TSO elongates the pipe, thus requiring a larger congestion window and larger buffering especially at the sender side. Therefore, it is important that applications 1) get a large enough socket send buffer (this is accomplished by our dynamic send buffer expansion code) 2) do large enough writes. Signed-off-by: David S. Miller <davem@davemloft.net>
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b4e26f5e |
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05-Jul-2005 |
David S. Miller <davem@davemloft.net> |
[TCP]: Fix send-side cpu utiliziation regression. Only put user data purely to pages when doing TSO. The extra page allocations cause two problems: 1) Add the overhead of the page allocations themselves. 2) Make us do small user copies when we get to the end of the TCP socket cache page. It is still beneficial to purely use pages for TSO, so we will do it for that case. Signed-off-by: David S. Miller <davem@davemloft.net>
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c65f7f00 |
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05-Jul-2005 |
David S. Miller <davem@davemloft.net> |
[TCP]: Simplify SKB data portion allocation with NETIF_F_SG. The ideal and most optimal layout for an SKB when doing scatter-gather is to put all the headers at skb->data, and all the user data in the page array. This makes SKB splitting and combining extremely simple, especially before a packet goes onto the wire the first time. So, when sk_stream_alloc_pskb() is given a zero size, make sure there is no skb_tailroom(). This is achieved by applying SKB_DATA_ALIGN() to the header length used here. Next, make select_size() in TCP output segmentation use a length of zero when NETIF_F_SG is true on the outgoing interface. Signed-off-by: David S. Miller <davem@davemloft.net>
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5f8ef48d |
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23-Jun-2005 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: Allow choosing TCP congestion control via sockopt. Allow using setsockopt to set TCP congestion control to use on a per socket basis. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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317a76f9 |
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23-Jun-2005 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: Add pluggable congestion control algorithm infrastructure. Allow TCP to have multiple pluggable congestion control algorithms. Algorithms are defined by a set of operations and can be built in or modules. The legacy "new RENO" algorithm is used as a starting point and fallback. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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7df55125 |
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19-Jun-2005 |
David S. Miller <davem@davemloft.net> |
[TCP]: Fix sysctl_tcp_low_latency When enabled, this should disable UCOPY prequeue'ing altogether, but it does not due to a missing test. Signed-off-by: David S. Miller <davem@davemloft.net>
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2ad69c55 |
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18-Jun-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[NET] rename struct tcp_listen_opt to struct listen_sock Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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0e87506f |
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18-Jun-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[NET] Generalise tcp_listen_opt This chunks out the accept_queue and tcp_listen_opt code and moves them to net/core/request_sock.c and include/net/request_sock.h, to make it useful for other transport protocols, DCCP being the first one to use it. Next patches will rename tcp_listen_opt to accept_sock and remove the inline tcp functions that just call a reqsk_queue_ function. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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60236fdd |
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18-Jun-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[NET] Rename open_request to request_sock Ok, this one just renames some stuff to have a better namespace and to dissassociate it from TCP: struct open_request -> struct request_sock tcp_openreq_alloc -> reqsk_alloc tcp_openreq_free -> reqsk_free tcp_openreq_fastfree -> __reqsk_free With this most of the infrastructure closely resembles a struct sock methods subset. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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2e6599cb |
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18-Jun-2005 |
Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
[NET] Generalise TCP's struct open_request minisock infrastructure Kept this first changeset minimal, without changing existing names to ease peer review. Basicaly tcp_openreq_alloc now receives the or_calltable, that in turn has two new members: ->slab, that replaces tcp_openreq_cachep ->obj_size, to inform the size of the openreq descendant for a specific protocol The protocol specific fields in struct open_request were moved to a class hierarchy, with the things that are common to all connection oriented PF_INET protocols in struct inet_request_sock, the TCP ones in tcp_request_sock, that is an inet_request_sock, that is an open_request. I.e. this uses the same approach used for the struct sock class hierarchy, with sk_prot indicating if the protocol wants to use the open_request infrastructure by filling in sk_prot->rsk_prot with an or_calltable. Results? Performance is improved and TCP v4 now uses only 64 bytes per open request minisock, down from 96 without this patch :-) Next changeset will rename some of the structs, fields and functions mentioned above, struct or_calltable is way unclear, better name it struct request_sock_ops, s/struct open_request/struct request_sock/g, etc. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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e7626486 |
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13-Jun-2005 |
Andi Kleen <ak@linux.intel.com> |
[TCP]: Adjust TCP mem order check to new alloc_large_system_hash Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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02c30a84 |
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05-May-2005 |
Jesper Juhl <juhl-lkml@dif.dk> |
[PATCH] update Ross Biro bouncing email address Ross moved. Remove the bad email address so people will find the correct one in ./CREDITS. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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1da177e4 |
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16-Apr-2005 |
Linus Torvalds <torvalds@ppc970.osdl.org> |
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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