#
dcee2280 |
|
28-Jan-2024 |
Yury Norov <yury.norov@gmail.com> |
cpumask: define cleanup function for cpumasks Now we can simplify code that allocates cpumasks for local needs. Signed-off-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
#
c1f5204e |
|
28-Jan-2024 |
Yury Norov <yury.norov@gmail.com> |
cpumask: add cpumask_weight_andnot() Similarly to cpumask_weight_and(), cpumask_weight_andnot() is a handy helper that may help to avoid creating an intermediate mask just to calculate number of bits that set in a 1st given mask, and clear in 2nd one. Signed-off-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
#
57f728d5 |
|
31-Jul-2023 |
Randy Dunlap <rdunlap@infradead.org> |
cpumask: kernel-doc cleanups and additions Clean up some punctutation and abbreviations. Add kernel-doc notation for one function and function return value for 39 functions. cpumask.h: Fix some punctuation (plural vs. possessive). Fix some abbreviations (ie. -> i.e., id -> ID). Fix 35 warnings like this: include/linux/cpumask.h:161: warning: No description found for return value of 'cpumask_first' cpumask.c: Add Return: value for 4 functions. Add kernel-doc for cpumask_any_distribute(). Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
dcb60f9c |
|
12-Jul-2023 |
Randy Dunlap <rdunlap@infradead.org> |
cpumask: eliminate kernel-doc warnings Update lib/cpumask.c and <linux/cpumask.h> to fix all kernel-doc warnings: include/linux/cpumask.h:185: warning: Function parameter or member 'srcp1' not described in 'cpumask_first_and' include/linux/cpumask.h:185: warning: Function parameter or member 'srcp2' not described in 'cpumask_first_and' include/linux/cpumask.h:185: warning: Excess function parameter 'src1p' description in 'cpumask_first_and' include/linux/cpumask.h:185: warning: Excess function parameter 'src2p' description in 'cpumask_first_and' lib/cpumask.c:59: warning: Function parameter or member 'node' not described in 'alloc_cpumask_var_node' lib/cpumask.c:169: warning: Function parameter or member 'src1p' not described in 'cpumask_any_and_distribute' lib/cpumask.c:169: warning: Function parameter or member 'src2p' not described in 'cpumask_any_and_distribute' Fixes: 7b4967c53204 ("cpumask: Add alloc_cpumask_var_node()") Fixes: 839cad5fa54b ("cpumask: fix function description kernel-doc notation") Fixes: 93ba139ba819 ("cpumask: use find_first_and_bit()") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
0f613bfa |
|
05-Jun-2023 |
Mark Rutland <mark.rutland@arm.com> |
locking/atomic: treewide: use raw_atomic*_<op>() Now that we have raw_atomic*_<op>() definitions, there's no need to use arch_atomic*_<op>() definitions outside of the low-level atomic definitions. Move treewide users of arch_atomic*_<op>() over to the equivalent raw_atomic*_<op>(). There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230605070124.3741859-19-mark.rutland@arm.com
|
#
1470afef |
|
15-Mar-2023 |
Dave Chinner <dchinner@redhat.com> |
cpumask: introduce for_each_cpu_or Equivalent of for_each_cpu_and, except it ORs the two masks together so it iterates all the CPUs present in either mask. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
|
#
e7304080 |
|
12-Mar-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
cpumask: relax sanity checking constraints The cpumask_check() was unnecessarily tight, and causes problems for the users of cpumask_next(). We have a number of users that take the previous return value of one of the bit scanning functions and subtract one to keep it in "range". But since the scanning functions end up returning up to 'small_cpumask_bits' instead of the tighter 'nr_cpumask_bits', the range really needs to be using that widened form. [ This "previous-1" behavior is also the reason we have all those comments about /* -1 is a legal arg here. */ and separate checks for that being ok. So we could have just made "small_cpumask_bits-1" be a similar special "don't check this" value. Tetsuo Handa even suggested a patch that only does that for cpumask_next(), since that seems to be the only actual case that triggers, but that all makes it even _more_ magical and special. So just relax the check ] One example of this kind of pattern being the 'c_start()' function in arch/x86/kernel/cpu/proc.c, but also duplicated in various forms on other architectures. Reported-by: syzbot+96cae094d90877641f32@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=96cae094d90877641f32 Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Link: https://lore.kernel.org/lkml/c1f4cc16-feea-b83c-82cf-1a1f007b7eb9@I-love.SAKURA.ne.jp/ Fixes: 596ff4a09b89 ("cpumask: re-introduce constant-sized cpumask optimizations") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
63355b98 |
|
07-Mar-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
cpumask: be more careful with 'cpumask_setall()' Commit 596ff4a09b89 ("cpumask: re-introduce constant-sized cpumask optimizations") changed cpumask_setall() to use "bitmap_set()" instead of "bitmap_fill()", because bitmap_fill() would explicitly set all the bits of a constant sized small bitmap, and that's exactly what we don't want: we want to only set bits up to 'nr_cpu_ids', which is what "bitmap_set()" does. However, Yury correctly points out that while "bitmap_set()" does indeed only set bits up to the required bitmap size, it doesn't _clear_ bits above that size, so the upper bits would still not have well-defined values. Now, none of this should really matter, since any bits set past 'nr_cpu_ids' should always be ignored in the first place. Yes, the bit scanning functions might return them as a result, but since users should always consider the ">= nr_cpu_ids" condition to mean "no more bits", that shouldn't have any actual effect (see previous commit 8ca09d5fa354 "cpumask: fix incorrect cpumask scanning result checks"). But let's just do it right, the way the code was _intended_ to work. We have had enough lazy code that works but bites us in the *rse later (again, see previous commit) that there's no reason to not just do this properly. It turns out that "bitmap_fill()" gets this all right for the complex case, and really only fails for the inlined optimized case that just fills the whole word. And while we could just fix bitmap_fill() to use the proper last word mask, there's two issues with that: - the cpumask case wants to do the _optimization_ based on "NR_CPUS is a small constant", but then wants to do the actual bit _fill_ based on "nr_cpu_ids" that isn't necessarily that same constant - we have lots of non-cpumask users of bitmap_fill(), and while they hopefully don't care, and probably would want the proper semantics anyway ("only set bits up to the limit"), I do not want the cpumask changes to impact other parts So this ends up just doing the single-word optimization by hand in the cpumask code. If our cpumask is fundamentally limited to a single word, just do the proper "fill in that word" exactly. And if it's the more complex multi-word case, then the generic bitmap_fill() will DTRT. This is all an example of how our bitmap function optimizations really are somewhat broken. They conflate the "this is size of the bitmap" optimizations with the actual bit(s) we want to set. In many cases we really want to have the two be separate things: sometimes we base our optimizations on the size of the whole bitmap ("I know this whole bitmap fits in a single word, so I'll just use single-word accesses"), and sometimes we base them on the bit we are looking at ("this is just acting on bits that are in the first word, so I'll use single-word accesses"). Notice how the end result of the two optimizations are the same, but the way we get to them are quite different. And all our cpumask optimization games are really about that fundamental distinction, and we'd often really want to pass in both the "this is the bit I'm working on" (which _can_ be a small constant but might be variable), and "I know it's in this range even if it's variable" (based on CONFIG_NR_CPUS). So this cpumask_setall() implementation just makes that explicit. It checks the "I statically know the size is small" using the known static size of the cpumask (which is what that 'small_cpumask_bits' is all about), but then sets the actual bits using the exact number of cpus we have (ie 'nr_cpumask_bits') Of course, in a perfect world, the compiler would have done all the range analysis (possibly with help from us just telling it that "this value is always in this range"), and would do all of this for us. But that is not the world we live in. While we dream of that perfect world, this does that manual logic to make it all work out. And this was a very long explanation for a small code change that shouldn't even matter. Reported-by: Yury Norov <yury.norov@gmail.com> Link: https://lore.kernel.org/lkml/ZAV9nGG9e1%2FrV+L%2F@yury-laptop/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
80c16b2b |
|
06-Mar-2023 |
Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
cpumask: Fix typo nr_cpumask_size --> nr_cpumask_bits The never used nr_cpumask_size is just a typo, hence use existing redefinition that's called nr_cpumask_bits. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
596ff4a0 |
|
04-Mar-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
cpumask: re-introduce constant-sized cpumask optimizations Commit aa47a7c215e7 ("lib/cpumask: deprecate nr_cpumask_bits") resulted in the cpumask operations potentially becoming hugely less efficient, because suddenly the cpumask was always considered to be variable-sized. The optimization was then later added back in a limited form by commit 6f9c07be9d02 ("lib/cpumask: add FORCE_NR_CPUS config option"), but that FORCE_NR_CPUS option is not useful in a generic kernel and more of a special case for embedded situations with fixed hardware. Instead, just re-introduce the optimization, with some changes. Instead of depending on CPUMASK_OFFSTACK being false, and then always using the full constant cpumask width, this introduces three different cpumask "sizes": - the exact size (nr_cpumask_bits) remains identical to nr_cpu_ids. This is used for situations where we should use the exact size. - the "small" size (small_cpumask_bits) is the NR_CPUS constant if it fits in a single word and the bitmap operations thus end up able to trigger the "small_const_nbits()" optimizations. This is used for the operations that have optimized single-word cases that get inlined, notably the bit find and scanning functions. - the "large" size (large_cpumask_bits) is the NR_CPUS constant if it is an sufficiently small constant that makes simple "copy" and "clear" operations more efficient. This is arbitrarily set at four words or less. As a an example of this situation, without this fixed size optimization, cpumask_clear() will generate code like movl nr_cpu_ids(%rip), %edx addq $63, %rdx shrq $3, %rdx andl $-8, %edx callq memset@PLT on x86-64, because it would calculate the "exact" number of longwords that need to be cleared. In contrast, with this patch, using a MAX_CPU of 64 (which is quite a reasonable value to use), the above becomes a single movq $0,cpumask instruction instead, because instead of caring to figure out exactly how many CPU's the system has, it just knows that the cpumask will be a single word and can just clear it all. Note that this does end up tightening the rules a bit from the original version in another way: operations that set bits in the cpumask are now limited to the actual nr_cpu_ids limit, whereas we used to do the nr_cpumask_bits thing almost everywhere in the cpumask code. But if you just clear bits, or scan for bits, we can use the simpler compile-time constants. In the process, remove 'cpumask_complement()' and 'for_each_cpu_not()' which were not useful, and which fundamentally have to be limited to 'nr_cpu_ids'. Better remove them now than have somebody introduce use of them later. Of course, on x86-64 with MAXSMP there is no sane small compile-time constant for the cpumask sizes, and we end up using the actual CPU bits, and will generate the above kind of horrors regardless. Please don't use MAXSMP unless you really expect to have machines with thousands of cores. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
62f4386e |
|
20-Jan-2023 |
Yury Norov <yury.norov@gmail.com> |
cpumask: introduce cpumask_nth_and_andnot Introduce cpumask_nth_and_andnot() based on find_nth_and_andnot_bit(). It's used in the following patch to traverse cpumasks without storing intermediate result in temporary cpumask. Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Tariq Toukan <tariqt@nvidia.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Peter Lafreniere <peter@n8pjl.ca> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
#
6a123d6a |
|
12-Jan-2023 |
Peter Zijlstra <peterz@infradead.org> |
cpuidle, ACPI: Make noinstr clean objtool found cases where ACPI methods called out into instrumentation code: vmlinux.o: warning: objtool: io_idle+0xc: call to __inb.isra.0() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_idle_enter+0xfe: call to num_online_cpus() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_idle_enter+0x115: call to acpi_idle_fallback_to_c1.isra.0() leaves .noinstr.text section Fix this by: marking the IO in/out, acpi_idle_fallback_to_c1() and num_online_cpus() methods as __always_inline. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230112195541.294846301@infradead.org
|
#
80493877 |
|
15-Oct-2022 |
Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> |
Revert "cpumask: fix checking valid cpu range". This reverts commit 78e5a3399421 ("cpumask: fix checking valid cpu range"). syzbot is hitting WARN_ON_ONCE(cpu >= nr_cpumask_bits) warning at cpu_max_bits_warn() [1], for commit 78e5a3399421 ("cpumask: fix checking valid cpu range") is broken. Obviously that patch hits WARN_ON_ONCE() when e.g. reading /proc/cpuinfo because passing "cpu + 1" instead of "cpu" will trivially hit cpu == nr_cpumask_bits condition. Although syzbot found this problem in linux-next.git on 2022/09/27 [2], this problem was not fixed immediately. As a result, that patch was sent to linux.git before the patch author recognizes this problem, and syzbot started failing to test changes in linux.git since 2022/10/10 [3]. Andrew Jones proposed a fix for x86 and riscv architectures [4]. But [2] and [5] indicate that affected locations are not limited to arch code. More delay before we find and fix affected locations, less tested kernel (and more difficult to bisect and fix) before release. We should have inspected and fixed basically all cpumask users before applying that patch. We should not crash kernels in order to ask existing cpumask users to update their code, even if limited to CONFIG_DEBUG_PER_CPU_MAPS=y case. Link: https://syzkaller.appspot.com/bug?extid=d0fd2bf0dd6da72496dd [1] Link: https://syzkaller.appspot.com/bug?extid=21da700f3c9f0bc40150 [2] Link: https://syzkaller.appspot.com/bug?extid=51a652e2d24d53e75734 [3] Link: https://lkml.kernel.org/r/20221014155845.1986223-1-ajones@ventanamicro.com [4] Link: https://syzkaller.appspot.com/bug?extid=4d46c43d81c3bd155060 [5] Reported-by: Andrew Jones <ajones@ventanamicro.com> Reported-by: syzbot+d0fd2bf0dd6da72496dd@syzkaller.appspotmail.com Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Yury Norov <yury.norov@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
5f75ff29 |
|
03-Oct-2022 |
Valentin Schneider <vschneid@redhat.com> |
cpumask: Introduce for_each_cpu_andnot() for_each_cpu_and() is very convenient as it saves having to allocate a temporary cpumask to store the result of cpumask_and(). The same issue applies to cpumask_andnot() which doesn't actually need temporary storage for iteration purposes. Following what has been done for for_each_cpu_and(), introduce for_each_cpu_andnot(). Signed-off-by: Valentin Schneider <vschneid@redhat.com>
|
#
78e5a339 |
|
19-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
cpumask: fix checking valid cpu range The range of valid CPUs is [0, nr_cpu_ids). Some cpumask functions are passed with a shifted CPU index, and for them, the valid range is [-1, nr_cpu_ids-1). Currently for those functions, we check the index against [-1, nr_cpu_ids), which is wrong. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
4fe49b3b |
|
19-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
lib/bitmap: introduce for_each_set_bit_wrap() macro Add for_each_set_bit_wrap() macro and use it in for_each_cpu_wrap(). The new macro is based on __for_each_wrap() iterator, which is simpler and smaller than cpumask_next_wrap(). Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
33e67710 |
|
19-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
cpumask: switch for_each_cpu{,_not} to use for_each_bit() The difference between for_each_cpu() and for_each_set_bit() is that the latter uses cpumask_next() instead of find_next_bit(), and so calls cpumask_check(). This check is useless because the iterator value is not provided by user. It generates false-positives for the very last iteration of for_each_cpu(). Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
944c417d |
|
17-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
cpumask: add cpumask_nth_{,and,andnot} Add cpumask_nth_{,and,andnot} as wrappers around corresponding find functions, and use it in cpumask_local_spread(). Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
24291caf |
|
17-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
lib/bitmap: add bitmap_weight_and() The function calculates Hamming weight of (bitmap1 & bitmap2). Now we have to do like this: tmp = bitmap_alloc(nbits); bitmap_and(tmp, map1, map2, nbits); weight = bitmap_weight(tmp, nbits); bitmap_free(tmp); This requires additional memory, adds pressure on alloc subsystem, and way less cache-friendly than just: weight = bitmap_weight_and(map1, map2, nbits); The following patches apply it for cpumask functions. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
6f9c07be |
|
05-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
lib/cpumask: add FORCE_NR_CPUS config option The size of cpumasks is hard-limited by compile-time parameter NR_CPUS, but defined at boot-time when kernel parses ACPI/DT tables, and stored in nr_cpu_ids. In many practical cases, number of CPUs for a target is known at compile time, and can be provided with NR_CPUS. In that case, compiler may be instructed to rely on NR_CPUS as on actual number of CPUs, not an upper limit. It allows to optimize many cpumask routines and significantly shrink size of the kernel image. This patch adds FORCE_NR_CPUS option to teach the compiler to rely on NR_CPUS and enable corresponding optimizations. If FORCE_NR_CPUS=y, kernel will not set nr_cpu_ids at boot, but only check that the actual number of possible CPUs is equal to NR_CPUS, and WARN if that doesn't hold. The new option is especially useful in embedded applications because kernel configurations are unique for each SoC, the number of CPUs is constant and known well, and memory limitations are typically harder. For my 4-CPU ARM64 build with NR_CPUS=4, FORCE_NR_CPUS=y saves 46KB: add/remove: 3/4 grow/shrink: 46/729 up/down: 652/-46952 (-46300) Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
aa47a7c2 |
|
05-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
lib/cpumask: deprecate nr_cpumask_bits Cpumask code is written in assumption that when CONFIG_CPUMASK_OFFSTACK is enabled, all cpumasks have boot-time defined size, otherwise the size is always NR_CPUS. The latter is wrong because the number of possible cpus is always calculated on boot, and it may be less than NR_CPUS. On my 4-cpu arm64 VM the nr_cpu_ids is 4, as expected, and nr_cpumask_bits is 256, which corresponds to NR_CPUS. This not only leads to useless traversing of cpumask bits greater than 4, this also makes some cpumask routines fail. For example, cpumask_full(0b1111000..000) would erroneously return false in the example above because tail bits in the mask are all unset. This patch deprecates nr_cpumask_bits and wires it to nr_cpu_ids unconditionally, so that cpumask routines will not waste time traversing unused part of cpu masks. It also fixes cpumask_full() and similar routines. As a side effect, because now a length of cpumasks is defined at run-time even if CPUMASK_OFFSTACK is disabled, compiler can't optimize corresponding functions. It increases kernel size by ~2.5KB if OFFSTACK is off. This is addressed in the following patch. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
7102b3bb |
|
05-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
lib/cpumask: delete misleading comment The comment says that HOTPLUG config option enables all cpus in cpu_possible_mask up to NR_CPUs. This is wrong. Even if HOTPLUG is enabled, the mask is populated on boot with respect to ACPI/DT records. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
38bef8e5 |
|
05-Sep-2022 |
Yury Norov <yury.norov@gmail.com> |
smp: add set_nr_cpu_ids() In preparation to support compile-time nr_cpu_ids, add a setter for the variable. This is a no-op for all arches. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
b9be19ee |
|
06-Sep-2022 |
Phil Auld <pauld@redhat.com> |
drivers/base: Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES As PAGE_SIZE is unsigned long, -1 > PAGE_SIZE when NR_CPUS <= 3. This leads to very large file sizes: topology$ ls -l total 0 -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 core_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 core_cpus_list -r--r--r-- 1 root root 4096 Sep 5 10:58 core_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 10:10 core_siblings -r--r--r-- 1 root root 4096 Sep 5 11:59 core_siblings_list -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 die_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 die_cpus_list -r--r--r-- 1 root root 4096 Sep 5 11:59 die_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 package_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 package_cpus_list -r--r--r-- 1 root root 4096 Sep 5 10:58 physical_package_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 10:10 thread_siblings -r--r--r-- 1 root root 4096 Sep 5 11:59 thread_siblings_list Adjust the inequality to catch the case when NR_CPUS is configured to a small value. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Yury Norov <yury.norov@gmail.com> Cc: stable@vger.kernel.org Cc: feng xiangjun <fengxj325@gmail.com> Fixes: 7ee951acd31a ("drivers/base: fix userspace break from using bin_attributes for cpumap and cpulist") Reported-by: feng xiangjun <fengxj325@gmail.com> Signed-off-by: Phil Auld <pauld@redhat.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
d7f06bdd |
|
06-Sep-2022 |
Phil Auld <pauld@redhat.com> |
drivers/base: Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES As PAGE_SIZE is unsigned long, -1 > PAGE_SIZE when NR_CPUS <= 3. This leads to very large file sizes: topology$ ls -l total 0 -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 core_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 core_cpus_list -r--r--r-- 1 root root 4096 Sep 5 10:58 core_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 10:10 core_siblings -r--r--r-- 1 root root 4096 Sep 5 11:59 core_siblings_list -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 die_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 die_cpus_list -r--r--r-- 1 root root 4096 Sep 5 11:59 die_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 package_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 package_cpus_list -r--r--r-- 1 root root 4096 Sep 5 10:58 physical_package_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 10:10 thread_siblings -r--r--r-- 1 root root 4096 Sep 5 11:59 thread_siblings_list Adjust the inequality to catch the case when NR_CPUS is configured to a small value. Fixes: 7ee951acd31a ("drivers/base: fix userspace break from using bin_attributes for cpumap and cpulist") Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Yury Norov <yury.norov@gmail.com> Cc: stable@vger.kernel.org Cc: feng xiangjun <fengxj325@gmail.com> Reported-by: feng xiangjun <fengxj325@gmail.com> Signed-off-by: Phil Auld <pauld@redhat.com> Signed-off-by: Yury Norov <yury.norov@gmail.com> Link: https://lore.kernel.org/r/20220906203542.1796629-1-pauld@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
#
2248ccd8 |
|
09-Aug-2022 |
Sander Vanheule <sander@svanheule.net> |
lib/cpumask: add inline cpumask_next_wrap() for UP In the uniprocessor case, cpumask_next_wrap() can be simplified, as the number of valid argument combinations is limited: - 'start' can only be 0 - 'n' can only be -1 or 0 The only valid CPU that can then be returned, if any, will be the first one set in the provided 'mask'. For NR_CPUS == 1, include/linux/cpumask.h now provides an inline definition of cpumask_next_wrap(), which will conflict with the one provided by lib/cpumask.c. Make building of lib/cpumask.o again depend on CONFIG_SMP=y (i.e. NR_CPUS > 1) to avoid the re-definition. Suggested-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Sander Vanheule <sander@svanheule.net> Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
be599244 |
|
09-Aug-2022 |
Sander Vanheule <sander@svanheule.net> |
cpumask: align signatures of UP implementations Between the generic version, and their uniprocessor optimised implementations, the return types of cpumask_any_and_distribute() and cpumask_any_distribute() are not identical. Change the UP versions to 'unsigned int', to match the generic versions. Suggested-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Sander Vanheule <sander@svanheule.net> Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
953257a9 |
|
02-Jul-2022 |
Sander Vanheule <sander@svanheule.net> |
cpumask: update cpumask_next_wrap() signature The extern specifier is not needed for this declaration, so drop it. The function also depends only on the input parameters, and has no side effects, so it can be marked __pure like other functions in cpumask.h. Link: https://lkml.kernel.org/r/72ab755695b74bb5fbaa756ae4c0edd708d172f1.1656777646.git.sander@svanheule.net Signed-off-by: Sander Vanheule <sander@svanheule.net> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Marco Elver <elver@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Yury Norov <yury.norov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
#
b81dce77 |
|
02-Jul-2022 |
Sander Vanheule <sander@svanheule.net> |
cpumask: Fix invalid uniprocessor mask assumption On uniprocessor builds, any CPU mask is assumed to contain exactly one CPU (cpu0). This assumption ignores the existence of empty masks, resulting in incorrect behaviour. cpumask_first_zero(), cpumask_next_zero(), and for_each_cpu_not() don't provide behaviour matching the assumption that a UP mask is always "1", and instead provide behaviour matching the empty mask. Drop the incorrectly optimised code and use the generic implementations in all cases. Link: https://lkml.kernel.org/r/86bf3f005abba2d92120ddd0809235cab4f759a6.1656777646.git.sander@svanheule.net Signed-off-by: Sander Vanheule <sander@svanheule.net> Suggested-by: Yury Norov <yury.norov@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Marco Elver <elver@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
#
4f099030 |
|
02-Jul-2022 |
Sander Vanheule <sander@svanheule.net> |
cpumask: add UP optimised for_each_*_cpu versions On uniprocessor builds, the following loops will always run over a mask that contains one enabled CPU (cpu0): - for_each_possible_cpu - for_each_online_cpu - for_each_present_cpu Provide uniprocessor-specific macros for these loops, that always run exactly once. Link: https://lkml.kernel.org/r/3a92869b902a075b97be5d1452c9c6badbbff0df.1656777646.git.sander@svanheule.net Signed-off-by: Sander Vanheule <sander@svanheule.net> Acked-by: Yury Norov <yury.norov@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Marco Elver <elver@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
#
f0dd891d |
|
01-Jul-2022 |
Yury Norov <yury.norov@gmail.com> |
lib/cpumask: move some one-line wrappers to header file After moving gfp flags to a separate header, it's possible to move some cpumask allocators into headers, and avoid creating real functions. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
9b2e7086 |
|
01-Jul-2022 |
Yury Norov <yury.norov@gmail.com> |
lib/cpumask: move trivial wrappers around find_bit to the header To avoid circular dependencies, cpumask keeps simple (almost) one-line wrappers around find_bit() in a c-file. Commit 47d8c15615c0a2 ("include: move find.h from asm_generic to linux") moved find.h header out of asm_generic include path, and it helped to fix many circular dependencies, including some in cpumask.h. This patch moves those one-liners to header files. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
8b6b795d |
|
01-Jul-2022 |
Yury Norov <yury.norov@gmail.com> |
lib/cpumask: change return types to unsigned where appropriate Switch return types to unsigned int where return values cannot be negative. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
cb32c285 |
|
01-Jul-2022 |
Yury Norov <yury.norov@gmail.com> |
cpumask: change return types to bool where appropriate Some cpumask functions have integer return types where return values are naturally booleans. Signed-off-by: Yury Norov <yury.norov@gmail.com>
|
#
7ee951ac |
|
15-Jul-2022 |
Phil Auld <pauld@redhat.com> |
drivers/base: fix userspace break from using bin_attributes for cpumap and cpulist Using bin_attributes with a 0 size causes fstat and friends to return that 0 size. This breaks userspace code that retrieves the size before reading the file. Rather than reverting 75bd50fa841 ("drivers/base/node.c: use bin_attribute to break the size limitation of cpumap ABI") let's put in a size value at compile time. For cpulist the maximum size is on the order of NR_CPUS * (ceil(log10(NR_CPUS)) + 1)/2 which for 8192 is 20480 (8192 * 5)/2. In order to get near that you'd need a system with every other CPU on one node. For example: (0,2,4,8, ... ). To simplify the math and support larger NR_CPUS in the future we are using (NR_CPUS * 7)/2. We also set it to a min of PAGE_SIZE to retain the older behavior for smaller NR_CPUS. The cpumap file the size works out to be NR_CPUS/4 + NR_CPUS/32 - 1 (or NR_CPUS * 9/32 - 1) including the ","s. Add a set of macros for these values to cpumask.h so they can be used in multiple places. Apply these to the handful of such files in drivers/base/topology.c as well as node.c. As an example, on an 80 cpu 4-node system (NR_CPUS == 8192): before: -r--r--r--. 1 root root 0 Jul 12 14:08 system/node/node0/cpulist -r--r--r--. 1 root root 0 Jul 11 17:25 system/node/node0/cpumap after: -r--r--r--. 1 root root 28672 Jul 13 11:32 system/node/node0/cpulist -r--r--r--. 1 root root 4096 Jul 13 11:31 system/node/node0/cpumap CONFIG_NR_CPUS = 16384 -r--r--r--. 1 root root 57344 Jul 13 14:03 system/node/node0/cpulist -r--r--r--. 1 root root 4607 Jul 13 14:02 system/node/node0/cpumap The actual number of cpus doesn't matter for the reported size since they are based on NR_CPUS. Fixes: 75bd50fa841d ("drivers/base/node.c: use bin_attribute to break the size limitation of cpumap ABI") Fixes: bb9ec13d156e ("topology: use bin_attribute to break the size limitation of cpumap ABI") Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Yury Norov <yury.norov@gmail.com> Cc: stable@vger.kernel.org Acked-by: Yury Norov <yury.norov@gmail.com> (for include/linux/cpumask.h) Signed-off-by: Phil Auld <pauld@redhat.com> Link: https://lore.kernel.org/r/20220715134924.3466194-1-pauld@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
#
f5c54f77 |
|
04-Feb-2022 |
Borislav Petkov <bp@suse.de> |
cpumask: Add a x86-specific cpumask_clear_cpu() helper Add a x86-specific cpumask_clear_cpu() helper which will be used in places where the explicit KASAN-instrumentation in the *_bit() helpers is unwanted. Also, always inline two more cpumask generic helpers. allyesconfig: text data bss dec hex filename 190553143 159425889 32076404 382055436 16c5b40c vmlinux.before 190551812 159424945 32076404 382053161 16c5ab29 vmlinux.after Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Marco Elver <elver@google.com> Link: https://lore.kernel.org/r/20220204083015.17317-2-bp@alien8.de
|
#
1dc01aba |
|
13-Jan-2022 |
Borislav Petkov <bp@suse.de> |
cpumask: Always inline helpers which use bit manipulation functions Former are always inlined so do that for the latter too, for consistency. Size impact is a whopping 5 bytes increase! :-) text data bss dec hex filename 22350551 8213184 1917164 32480899 1ef9e83 vmlinux.x86-64.defconfig.before 22350556 8213152 1917164 32480872 1ef9e68 vmlinux.x86-64.defconfig.after Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Marco Elver <elver@google.com> Link: https://lore.kernel.org/r/20220113155357.4706-3-bp@alien8.de
|
#
9b51d9d8 |
|
14-Aug-2021 |
Yury Norov <yury.norov@gmail.com> |
cpumask: replace cpumask_next_* with cpumask_first_* where appropriate cpumask_first() is a more effective analogue of 'next' version if n == -1 (which means start == 0). This patch replaces 'next' with 'first' where things look trivial. There's no cpumask_first_zero() function, so create it. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
|
#
93ba139b |
|
14-Aug-2021 |
Yury Norov <yury.norov@gmail.com> |
cpumask: use find_first_and_bit() Now we have an efficient implementation for find_first_and_bit(), so switch cpumask to use it where appropriate. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
|
#
c86a2d90 |
|
16-Sep-2021 |
Tobias Klauser <tklauser@distanz.ch> |
cpumask: Omit terminating null byte in cpumap_print_{list,bitmask}_to_buf The changes in the patch series [1] introduced a terminating null byte when reading from cpulist or cpumap sysfs files, for example: $ xxd /sys/devices/system/node/node0/cpulist 00000000: 302d 310a 00 0-1.. Before this change, the output looked as follows: $ xxd /sys/devices/system/node/node0/cpulist 00000000: 302d 310a 0-1. Fix this regression by excluding the terminating null byte from the returned length in cpumap_print_list_to_buf and cpumap_print_bitmask_to_buf. [1] https://lore.kernel.org/all/20210806110251.560-1-song.bao.hua@hisilicon.com/ Fixes: 1fae562983ca ("cpumask: introduce cpumap_print_list/bitmask_to_buf to support large bitmask and list") Acked-by: Barry Song <song.bao.hua@hisilicon.com> Acked-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Link: https://lore.kernel.org/r/20210916222705.13554-1-tklauser@distanz.ch Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
#
1fae5629 |
|
06-Aug-2021 |
Tian Tao <tiantao6@hisilicon.com> |
cpumask: introduce cpumap_print_list/bitmask_to_buf to support large bitmask and list The existing cpumap_print_to_pagebuf() is used by cpu topology and other drivers to export hexadecimal bitmask and decimal list to userspace by sysfs ABI. Right now, those drivers are using a normal attribute for this kind of ABIs. A normal attribute typically has show entry as below: static ssize_t example_dev_show(struct device *dev, struct device_attribute *attr, char *buf) { ... return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu); } show entry of attribute has no offset and count parameters and this means the file is limited to one page only. cpumap_print_to_pagebuf() API works terribly well for this kind of normal attribute with buf parameter and without offset, count: static inline ssize_t cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask) { return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask), nr_cpu_ids); } The problem is once we have many cpus, we have a chance to make bitmask or list more than one page. Especially for list, it could be as complex as 0,3,5,7,9,...... We have no simple way to know it exact size. It turns out bin_attribute is a way to break this limit. bin_attribute has show entry as below: static ssize_t example_bin_attribute_show(struct file *filp, struct kobject *kobj, struct bin_attribute *attr, char *buf, loff_t offset, size_t count) { ... } With the new offset and count parameters, this makes sysfs ABI be able to support file size more than one page. For example, offset could be >= 4096. This patch introduces cpumap_print_bitmask/list_to_buf() and their bitmap infrastructure bitmap_print_bitmask/list_to_buf() so that those drivers can move to bin_attribute to support large bitmask and list. At the same time, we have to pass those corresponding parameters such as offset, count from bin_attribute to this new API. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: "Ma, Jianpeng" <jianpeng.ma@intel.com> Cc: Yury Norov <yury.norov@gmail.com> Cc: Valentin Schneider <valentin.schneider@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Link: https://lore.kernel.org/r/20210806110251.560-2-song.bao.hua@hisilicon.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
#
c23c8082 |
|
07-Jul-2021 |
Zhen Lei <thunder.leizhen@huawei.com> |
lib: fix spelling mistakes in header files Fix some spelling mistakes in comments found by "codespell": Hoever ==> However poiter ==> pointer representaion ==> representation uppon ==> upon independend ==> independent aquired ==> acquired mis-match ==> mismatch scrach ==> scratch struture ==> structure Analagous ==> Analogous interation ==> iteration And some were discovered manually by Joe Perches and Christoph Lameter: stroed ==> stored arch independent ==> an architecture independent A example structure for ==> Example structure for Link: https://lkml.kernel.org/r/20210609150027.14805-2-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Cc: Christoph Lameter <cl@gentwo.de> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Dennis Zhou <dennis@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
291c4011 |
|
20-Feb-2021 |
Nadav Amit <namit@vmware.com> |
cpumask: Mark functions as pure cpumask_next_and() and cpumask_any_but() are pure, and marking them as such seems to generate different and presumably better code for native_flush_tlb_multi(). Signed-off-by: Nadav Amit <namit@vmware.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/20210220231712.2475218-8-namit@vmware.com
|
#
e40f74c5 |
|
19-Jan-2021 |
Peter Zijlstra <peterz@infradead.org> |
cpumask: Introduce DYING mask Introduce a cpumask that indicates (for each CPU) what direction the CPU hotplug is currently going. Notably, it tracks rollbacks. Eg. when an up fails and we do a roll-back down, it will accurately reflect the direction. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210310150109.151441252@infradead.org
|
#
b02a4fd8 |
|
25-Jan-2021 |
Peter Zijlstra <peterz@infradead.org> |
cpumask: Make cpu_{online,possible,present,active}() inline Prepare for addition of another mask. Primarily a code movement to avoid having to create more #ifdef, but while there, convert everything with an argument to an inline function. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210310150109.045447765@infradead.org
|
#
14e292f8 |
|
01-Oct-2020 |
Peter Zijlstra <peterz@infradead.org> |
sched,rt: Use cpumask_any*_distribute() Replace a bunch of cpumask_any*() instances with cpumask_any*_distribute(), by injecting this little bit of random in cpu selection, we reduce the chance two competing balance operations working off the same lowest_mask pick the same CPU. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Link: https://lkml.kernel.org/r/20201023102347.190759694@infradead.org
|
#
46a87b38 |
|
10-Mar-2020 |
Paul Turner <pjt@google.com> |
sched/core: Distribute tasks within affinity masks Currently, when updating the affinity of tasks via either cpusets.cpus, or, sched_setaffinity(); tasks not currently running within the newly specified mask will be arbitrarily assigned to the first CPU within the mask. This (particularly in the case that we are restricting masks) can result in many tasks being assigned to the first CPUs of their new masks. This: 1) Can induce scheduling delays while the load-balancer has a chance to spread them between their new CPUs. 2) Can antogonize a poor load-balancer behavior where it has a difficult time recognizing that a cross-socket imbalance has been forced by an affinity mask. This change adds a new cpumask interface to allow iterated calls to distribute within the intersection of the provided masks. The cases that this mainly affects are: - modifying cpuset.cpus - when tasks join a cpuset - when modifying a task's affinity via sched_setaffinity(2) Signed-off-by: Paul Turner <pjt@google.com> Signed-off-by: Josh Don <joshdon@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Qais Yousef <qais.yousef@arm.com> Tested-by: Qais Yousef <qais.yousef@arm.com> Link: https://lkml.kernel.org/r/20200311010113.136465-1-joshdon@google.com
|
#
190535f7 |
|
03-Feb-2020 |
Yury Norov <yury.norov@gmail.com> |
include/linux/cpumask.h: don't calculate length of the input string New design of inner bitmap_parse() allows to avoid calculating the size of a null-terminated string. Link: http://lkml.kernel.org/r/20200102043031.30357-8-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Amritha Nambiar <amritha.nambiar@intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: "Tobin C . Harding" <tobin@kernel.org> Cc: Vineet Gupta <vineet.gupta1@synopsys.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
2a4a4082 |
|
25-Sep-2019 |
Alexey Dobriyan <adobriyan@gmail.com> |
cpumask: nicer for_each_cpumask_and() signature Mask arguments can be swapped without changing anything. Make arguments names reflect that: #define for_each_cpu_and(cpu, mask1, mask2) Link: http://lkml.kernel.org/r/20190724183350.GA15041@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
0c09ab96 |
|
09-Jul-2019 |
Thomas Gleixner <tglx@linutronix.de> |
cpu/hotplug: Cache number of online CPUs Re-evaluating the bitmap wheight of the online cpus bitmap in every invocation of num_online_cpus() over and over is a pretty useless exercise. Especially when num_online_cpus() is used in code paths like the IPI delivery of x86 or the membarrier code. Cache the number of online CPUs in the core and just return the cached variable. The accessor function provides only a snapshot when used without protection against concurrent CPU hotplug. The storage needs to use an atomic_t because the kexec and reboot code (ab)use set_cpu_online() in their 'shutdown' handlers without any form of serialization as pointed out by Mathieu. Regular CPU hotplug usage is properly serialized. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1907091622590.1634@nanos.tec.linutronix.de
|
#
b9fa6442 |
|
22-Jul-2019 |
Thomas Gleixner <tglx@linutronix.de> |
cpumask: Implement cpumask_or_equal() The IPI code of x86 needs to evaluate whether the target cpumask is equal to the cpu_online_mask or equal except for the calling CPU. To replace the current implementation which requires the usage of a temporary cpumask, which might involve allocations, add a new function which compares a cpumask to the result of two other cpumasks which are or'ed together before comparison. This allows to make the required decision in one go and the calling code then can check for the calling CPU being set in the target mask with cpumask_test_cpu(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20190722105220.585449120@linutronix.de
|
#
e797bda3 |
|
22-Jul-2019 |
Thomas Gleixner <tglx@linutronix.de> |
smp/hotplug: Track booted once CPUs in a cpumask The booted once information which is required to deal with the MCE broadcast issue on X86 correctly is stored in the per cpu hotplug state, which is perfectly fine for the intended purpose. X86 needs that information for supporting NMI broadcasting via shortcuts, but retrieving it from per cpu data is cumbersome. Move it to a cpumask so the information can be checked against the cpu_present_mask quickly. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20190722105219.818822855@linutronix.de
|
#
3713a4e1 |
|
14-May-2019 |
Yury Norov <ynorov@marvell.com> |
include/linux/cpumask.h: fix double string traverse in cpumask_parse cpumask_parse() finds first occurrence of either or strchr() and strlen(). We can do it better with a single call of strchrnul(). [akpm@linux-foundation.org: remove unneeded cast] Link: http://lkml.kernel.org/r/20190409204208.12190-1-ynorov@marvell.com Signed-off-by: Yury Norov <ynorov@marvell.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
9af18e56 |
|
12-Aug-2018 |
Willem de Bruijn <willemb@google.com> |
cpumask: make cpumask_next_wrap available without smp The kbuild robot shows build failure on machines without CONFIG_SMP: drivers/net/virtio_net.c:1916:10: error: implicit declaration of function 'cpumask_next_wrap' cpumask_next_wrap is exported from lib/cpumask.o, which has lib-$(CONFIG_SMP) += cpumask.o same as other functions, also define it as static inline in the NR_CPUS==1 branch in include/linux/cpumask.h. If wrap is true and next == start, return nr_cpumask_bits, or 1. Else wrap across the range of valid cpus, here [0]. Fixes: 2ca653d607ce ("virtio_net: Stripe queue affinities across cores.") Signed-off-by: Willem de Bruijn <willemb@google.com> Tested-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
80d19669 |
|
29-Jun-2018 |
Amritha Nambiar <amritha.nambiar@intel.com> |
net: Refactor XPS for CPUs and Rx queues Refactor XPS code to support Tx queue selection based on CPU(s) map or Rx queue(s) map. Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
d207af2e |
|
13-Feb-2018 |
Michael Kelley <mhkelley@outlook.com> |
cpumask: Make for_each_cpu_wrap() available on UP as well for_each_cpu_wrap() was originally added in the #else half of a large "#if NR_CPUS == 1" statement, but was omitted in the #if half. This patch adds the missing #if half to prevent compile errors when NR_CPUS is 1. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Michael Kelley <mhkelley@outlook.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kys@microsoft.com Cc: martin.petersen@oracle.com Cc: mikelley@microsoft.com Fixes: c743f0a5c50f ("sched/fair, cpumask: Export for_each_cpu_wrap()") Link: http://lkml.kernel.org/r/SN6PR1901MB2045F087F59450507D4FCC17CBF50@SN6PR1901MB2045.namprd19.prod.outlook.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
#
4de373a1 |
|
06-Feb-2018 |
Alexey Dobriyan <adobriyan@gmail.com> |
cpumask: make cpumask_size() return "unsigned int" CPUmasks are never big enough to warrant 64-bit code. Space savings: add/remove: 0/0 grow/shrink: 1/4 up/down: 3/-17 (-14) Function old new delta sched_init_numa 1530 1533 +3 compat_sys_sched_setaffinity 160 159 -1 sys_sched_getaffinity 197 195 -2 sys_sched_setaffinity 183 176 -7 compat_sys_sched_getaffinity 179 172 -7 Link: http://lkml.kernel.org/r/20171204165531.GA8221@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
b2441318 |
|
01-Nov-2017 |
Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
#
e22cdc3f |
|
23-Oct-2017 |
Rakib Mullick <rakib.mullick@gmail.com> |
sched/isolcpus: Fix "isolcpus=" boot parameter handling when !CONFIG_CPUMASK_OFFSTACK cpulist_parse() uses nr_cpumask_bits as a limit to parse the passed buffer from kernel commandline. What nr_cpumask_bits represents varies depending upon the CONFIG_CPUMASK_OFFSTACK option: - If CONFIG_CPUMASK_OFFSTACK=n, then nr_cpumask_bits is the same as NR_CPUS, which might not represent the # of CPUs that really exist (default 64). So, there's a chance of a gap between nr_cpu_ids and NR_CPUS, which ultimately lead towards invalid cpulist_parse() operation. For example, if isolcpus=9 is passed on an 8 cpu system (CONFIG_CPUMASK_OFFSTACK=n) it doesn't show the error that it's supposed to. This patch fixes this bug by finding the last CPU of the passed isolcpus= list and checking it against nr_cpu_ids. It also fixes the error message where the nr_cpu_ids should be nr_cpu_ids-1, since CPU numbering starts from 0. Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: adobriyan@gmail.com Cc: akpm@linux-foundation.org Cc: longman@redhat.com Cc: mka@chromium.org Cc: tj@kernel.org Link: http://lkml.kernel.org/r/20171023130154.9050-1-rakib.mullick@gmail.com [ Enhanced the changelog and the kernel message. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> include/linux/cpumask.h | 16 ++++++++++++++++ kernel/sched/topology.c | 4 ++-- 2 files changed, 18 insertions(+), 2 deletions(-)
|
#
f22ef333 |
|
08-Sep-2017 |
Alexey Dobriyan <adobriyan@gmail.com> |
cpumask: make cpumask_next() out-of-line Every for_each_XXX_cpu() invocation calls cpumask_next() which is an inline function: static inline unsigned int cpumask_next(int n, const struct cpumask *srcp) { /* -1 is a legal arg here. */ if (n != -1) cpumask_check(n); return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1); } However! find_next_bit() is regular out-of-line function which means "nr_cpu_ids" load and increment happen at the caller resulting in a lot of bloat x86_64 defconfig: add/remove: 3/0 grow/shrink: 8/373 up/down: 155/-5668 (-5513) x86_64 allyesconfig-ish: add/remove: 3/1 grow/shrink: 57/634 up/down: 3515/-28177 (-24662) !!! Some archs redefine find_next_bit() but it is OK: m68k inline but SMP is not supported arm out-of-line unicore32 out-of-line Function call will happen anyway, so move load and increment into callee. Link: http://lkml.kernel.org/r/20170824230010.GA1593@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
9b130ad5 |
|
08-Sep-2017 |
Alexey Dobriyan <adobriyan@gmail.com> |
treewide: make "nr_cpu_ids" unsigned First, number of CPUs can't be negative number. Second, different signnnedness leads to suboptimal code in the following cases: 1) kmalloc(nr_cpu_ids * sizeof(X)); "int" has to be sign extended to size_t. 2) while (loff_t *pos < nr_cpu_ids) MOVSXD is 1 byte longed than the same MOV. Other cases exist as well. Basically compiler is told that nr_cpu_ids can't be negative which can't be deduced if it is "int". Code savings on allyesconfig kernel: -3KB add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370) function old new delta coretemp_cpu_online 450 512 +62 rcu_init_one 1234 1272 +38 pci_device_probe 374 399 +25 ... pgdat_reclaimable_pages 628 556 -72 select_fallback_rq 446 369 -77 task_numa_find_cpu 1923 1807 -116 Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
6c8557bd |
|
18-May-2017 |
Peter Zijlstra <peterz@infradead.org> |
smp, cpumask: Use non-atomic cpumask_{set,clear}_cpu() The cpumasks in smp_call_function_many() are private and not subject to concurrency, atomic bitops are pointless and expensive. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
#
c743f0a5 |
|
14-Apr-2017 |
Peter Zijlstra <peterz@infradead.org> |
sched/fair, cpumask: Export for_each_cpu_wrap() More users for for_each_cpu_wrap() have appeared. Promote the construct to generic cpumask interface. The implementation is slightly modified to reduce arguments. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Lauro Ramos Venancio <lvenanci@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: lwang@redhat.com Link: http://lkml.kernel.org/r/20170414122005.o35me2h5nowqkxbv@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
#
c311c797 |
|
08-May-2017 |
Alexey Dobriyan <adobriyan@gmail.com> |
cpumask: make "nr_cpumask_bits" unsigned Bit searching functions accept "unsigned long" indices but "nr_cpumask_bits" is "int" which is signed, so inevitable sign extensions occur on x86_64. Those MOVSX are #1 MOVSX bloat by number of uses across whole kernel. Change "nr_cpumask_bits" to unsigned, this number can't be negative after all. It allows to do implicit zero-extension on x86_64 without MOVSX. Change signed comparisons into unsigned comparisons where necessary. Other uses looks fine because it is either argument passed to a function or comparison is already unsigned. Net win on allyesconfig type of kernel: ~2.8 KB (!) add/remove: 0/0 grow/shrink: 8/725 up/down: 93/-2926 (-2833) function old new delta xen_exit_mmap 691 735 +44 qstat_read 426 440 +14 __cpufreq_cooling_register 1678 1687 +9 trace_rb_cpu_prepare 447 455 +8 vermagic 54 60 +6 nfp_driver_version 54 60 +6 rcu_torture_stats_print 1147 1151 +4 find_next_push_cpu 267 269 +2 xen_irq_resume 961 960 -1 ... init_vp_index 946 906 -40 od_set_powersave_bias 328 281 -47 power_cpu_exit 193 139 -54 arch_show_interrupts 3538 3484 -54 select_idle_sibling 1558 1471 -87 Total: Before=158358910, After=158356077, chg -0.00% Same arguments apply to "nr_cpu_ids" but I haven't yet found enough courage to delve into this issue (and proper fix may require new type "cpu_t" which is whole separate story). Link: http://lkml.kernel.org/r/20170309205322.GA1728@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
f7e30f01 |
|
12-Apr-2017 |
Matthias Kaehlcke <mka@chromium.org> |
cpumask: Add helper cpumask_available() With CONFIG_CPUMASK_OFFSTACK=y cpumask_var_t is a struct cpumask pointer, otherwise a struct cpumask array with a single element. Some code dealing with cpumasks needs to validate that a cpumask_var_t is not a NULL pointer when CONFIG_CPUMASK_OFFSTACK=y. This is typically done by performing the check always, regardless of the underlying type of cpumask_var_t. This works in both cases, however clang raises a warning like this when CONFIG_CPUMASK_OFFSTACK=n: kernel/irq/manage.c:839:28: error: address of array 'desc->irq_common_data.affinity' will always evaluate to 'true' [-Werror,-Wpointer-bool-conversion] Add the inline helper cpumask_available() which only performs the pointer check if CONFIG_CPUMASK_OFFSTACK=y. Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Cc: Grant Grundler <grundler@chromium.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg Hackmann <ghackmann@google.com> Cc: Michael Davidson <md@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20170412182030.83657-1-mka@chromium.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
#
4d59b6cc |
|
08-Feb-2017 |
Tejun Heo <tj@kernel.org> |
cpumask: use nr_cpumask_bits for parsing functions Commit 513e3d2d11c9 ("cpumask: always use nr_cpu_ids in formatting and parsing functions") converted both cpumask printing and parsing functions to use nr_cpu_ids instead of nr_cpumask_bits. While this was okay for the printing functions as it just picked one of the two output formats that we were alternating between depending on a kernel config, doing the same for parsing wasn't okay. nr_cpumask_bits can be either nr_cpu_ids or NR_CPUS. We can always use nr_cpu_ids but that is a variable while NR_CPUS is a constant, so it can be more efficient to use NR_CPUS when we can get away with it. Converting the printing functions to nr_cpu_ids makes sense because it affects how the masks get presented to userspace and doesn't break anything; however, using nr_cpu_ids for parsing functions can incorrectly leave the higher bits uninitialized while reading in these masks from userland. As all testing and comparison functions use nr_cpumask_bits which can be larger than nr_cpu_ids, the parsed cpumasks can erroneously yield false negative results. This made the taskstats interface incorrectly return -EINVAL even when the inputs were correct. Fix it by restoring the parse functions to use nr_cpumask_bits instead of nr_cpu_ids. Link: http://lkml.kernel.org/r/20170206182442.GB31078@htj.duckdns.org Fixes: 513e3d2d11c9 ("cpumask: always use nr_cpu_ids in formatting and parsing functions") Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Martin Steigerwald <martin.steigerwald@teamix.de> Debugged-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Cc: <stable@vger.kernel.org> [4.0+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
668802c2 |
|
29-Jan-2017 |
Waiman Long <longman@redhat.com> |
tick/broadcast: Reduce lock cacheline contention It was observed that on an Intel x86 system without the ARAT (Always running APIC timer) feature and with fairly large number of CPUs as well as CPUs coming in and out of intel_idle frequently, the lock contention on the tick_broadcast_lock can become significant. To reduce contention, the lock is put into its own cacheline and all the cpumask_var_t variables are put into the __read_mostly section. Running the SP benchmark of the NAS Parallel Benchmarks on a 4-socket 16-core 32-thread Nehalam system, the performance number improved from 3353.94 Mop/s to 3469.31 Mop/s when this patch was applied on a 4.9.6 kernel. This is a 3.4% improvement. Signed-off-by: Waiman Long <longman@redhat.com> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1485799063-20857-1-git-send-email-longman@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
#
427d77a3 |
|
13-Dec-2016 |
Thomas Gleixner <tglx@linutronix.de> |
x86/smpboot: Prevent false positive out of bounds cpumask access warning prefill_possible_map() reinitializes the cpu_possible_map by setting the possible cpu bits and clearing all other bits up to NR_CPUS. This is technically always correct because cpu_possible_map is statically allocated and sized NR_CPUS. With CPUMASK_OFFSTACK and DEBUG_PER_CPU_MAPS enabled the bounds check of cpu masks happens on nr_cpu_ids. nr_cpu_ids is initialized to NR_CPUS and only limited after the set/clear bit loops have been executed. But if the system was booted with "nr_cpus=N" on the command line, where N is < NR_CPUS then nr_cpu_ids is limited in the parameter parsing function before prefill_possible_map() is invoked. As a consequence the cpumask bounds check triggers when clearing the bits past nr_cpu_ids. Add a helper which allows to reset cpu_possible_map w/o the bounds check and then set only the possible bits which are well inside bounds. Reported-by: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: 0x7f454c46@gmail.com Cc: Jan Beulich <JBeulich@novell.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1612131836050.3415@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
#
b06fb415 |
|
02-Aug-2016 |
Geliang Tang <geliangtang@gmail.com> |
cpumask: fix code comment Fix code comment for cpumask_parse(). Link: http://lkml.kernel.org/r/71aae2c60ae5dae0cf554199ce6aea8f88c69347.1465380581.git.geliangtang@gmail.com Signed-off-by: Geliang Tang <geliangtang@gmail.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
e9d867a6 |
|
09-Mar-2016 |
Peter Zijlstra (Intel) <peterz@infradead.org> |
sched: Allow per-cpu kernel threads to run on online && !active In order to enable symmetric hotplug, we must mirror the online && !active state of cpu-down on the cpu-up side. However, to retain sanity, limit this state to per-cpu kthreads. Aside from the change to set_cpus_allowed_ptr(), which allow moving the per-cpu kthreads on, the other critical piece is the cpu selection for pinned tasks in select_task_rq(). This avoids dropping into select_fallback_rq(). select_fallback_rq() cannot be allowed to select !active cpus because its used to migrate user tasks away. And we do not want to move user tasks onto cpus that are in transition. Requested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Thomas Gleixner <tglx@linutronix.de> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160301152303.GV6356@twins.programming.kicks-ass.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
#
95f27356 |
|
22-Mar-2016 |
Eric Biggers <ebiggers3@gmail.com> |
cpumask: remove incorrect information from comment Since commit cdfdef75e795 ("cpumask: only allocate nr_cpumask_bits."), this comment above cpumask_size() is no longer relevant. Signed-off-by: Eric Biggers <ebiggers3@gmail.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
9425676a |
|
20-Jan-2016 |
Rasmus Villemoes <linux@rasmusvillemoes.dk> |
kernel/cpu.c: make set_cpu_* static inlines Almost all callers of the set_cpu_* functions pass an explicit true or false. Making them static inline thus replaces the function calls with a simple set_bit/clear_bit, saving some .text. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
5aec01b8 |
|
20-Jan-2016 |
Rasmus Villemoes <linux@rasmusvillemoes.dk> |
kernel/cpu.c: eliminate cpu_*_mask Replace the variables cpu_possible_mask, cpu_online_mask, cpu_present_mask and cpu_active_mask with macros expanding to expressions of the same type and value, eliminating some indirection. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
4b804c85 |
|
20-Jan-2016 |
Rasmus Villemoes <linux@rasmusvillemoes.dk> |
kernel/cpu.c: export __cpu_*_mask Exporting the cpumasks __cpu_possible_mask and friends will allow us to remove the extra indirection through the cpu_*_mask variables. It will also allow the set_cpu_* functions to become static inlines, which will give a .text reduction. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
f36963c9 |
|
08-May-2015 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask_set_cpu_local_first => cpumask_local_spread, lament da91309e0a7e (cpumask: Utility function to set n'th cpu...) created a genuinely weird function. I never saw it before, it went through DaveM. (He only does this to make us other maintainers feel better about our own mistakes.) cpumask_set_cpu_local_first's purpose is say "I need to spread things across N online cpus, choose the ones on this numa node first"; you call it in a loop. It can fail. One of the two callers ignores this, the other aborts and fails the device open. It can fail in two ways: allocating the off-stack cpumask, or through a convoluted codepath which AFAICT can only occur if cpu_online_mask changes. Which shouldn't happen, because if cpu_online_mask can change while you call this, it could return a now-offline cpu anyway. It contains a nonsensical test "!cpumask_of_node(numa_node)". This was drawn to my attention by Geert, who said this causes a warning on Sparc. It sets a single bit in a cpumask instead of returning a cpu number, because that's what the callers want. It could be made more efficient by passing the previous cpu rather than an index, but that would be more invasive to the callers. Fixes: da91309e0a7e8966d916a74cce42ed170fde06bf Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (then rebased) Tested-by: Amir Vadai <amirv@mellanox.com> Acked-by: Amir Vadai <amirv@mellanox.com> Acked-by: David S. Miller <davem@davemloft.net>
|
#
1527781d |
|
15-Apr-2015 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: resurrect CPU_MASK_CPU0 We removed it in 2f0f267ea072 (cpumask: remove deprecated functions.), but grep shows it still used by MIPS, and not unreasonably. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
3bbf7f46 |
|
30-Mar-2015 |
Rasmus Villemoes <linux@rasmusvillemoes.dk> |
linux/cpumask.h: add typechecking to cpumask_test_cpu The Subtlety (1) referred to vanished with 6ba2ef7baac2 ("cpumask: Move deprecated functions to end of header."). That used to mention some suboptimal code generation by a, by now, rather ancient gcc. With gcc 4.7, I don't see any change in the generated code by making it a static inline, so let's add type checking and get rid of the ghost reference. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
cdfdef75 |
|
04-Mar-2015 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: only allocate nr_cpumask_bits. Now we'll find out the hard way if anyone has CPUMASK_OFFSTACK and is returning these or assigning them. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
2f0f267e |
|
04-Mar-2015 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: remove deprecated functions. Using these functions with offstack cpus is unsafe. They use all NR_CPUS bits, unstead of nr_cpumask_bits. In particular, lustre (in staging) used cpus_ and that caused a bug. Reported-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
9941a383 |
|
04-Mar-2015 |
Rusty Russell <rusty@rustcorp.com.au> |
CPU_MASK_ALL/CPU_MASK_NONE: remove from deprecated region. They're used to initialize various static fields, though static cpumasks should generally be avoided. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
46385326 |
|
13-Feb-2015 |
Tejun Heo <tj@kernel.org> |
bitmap, cpumask, nodemask: remove dedicated formatting functions Now that all bitmap formatting usages have been converted to '%*pb[l]', the separate formatting functions are unnecessary. The following functions are removed. * bitmap_scn[list]printf() * cpumask_scnprintf(), cpulist_scnprintf() * [__]nodemask_scnprintf(), [__]nodelist_scnprintf() * seq_bitmap[_list](), seq_cpumask[_list](), seq_nodemask[_list]() * seq_buf_bitmask() Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
f1bbc032 |
|
13-Feb-2015 |
Tejun Heo <tj@kernel.org> |
cpumask, nodemask: implement cpumask/nodemask_pr_args() printf family of functions can now format bitmaps using '%*pb[l]' and all cpumask and nodemask formatting will be converted to use it. To ease printing these masks with '%*pb[l]' which require two params - the number of bits and the actual bitmap, this patch implement cpumask_pr_args() and nodemask_pr_args() which can be used to provide arguments for '%*pb[l]' Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
513e3d2d |
|
13-Feb-2015 |
Tejun Heo <tj@kernel.org> |
cpumask: always use nr_cpu_ids in formatting and parsing functions bitmap implements two variants of scnprintf functions to format a bitmap into a string and cpumask and nodemask wrap them to provide equivalent interfaces. The scnprintf family of functions require a string buffer as an output target which complicates code paths which just want to print out the mask through printk for informational or debug purposes as they have to worry about how large the buffer should be and whether it's too large to allocate on stack. Neither cpumask or nodemask provides a guildeline on how large the target buffer should be forcing users come up with their own solutions - some allocate an arbitrarily sized buffer which is small enough to allocate on stack but may be too short in corner cases, other come up with a custom upper limit calculation considering the output format, some allocate the buffer dynamically while one resorted to using lock to synchronize access to a static buffer. This is an artificial problem which is being solved repeatedly for no benefit. In a lot of cases, the output area already exists and can be targeted directly making the intermediate buffer unnecessary. This patchset teaches printf family of functions how to format bitmaps and replace the dedicated formatting functions with it. Pointer formatting is extended to cover bitmap formatting. It uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. For more details, please see 0002. This patch (of 31): Currently, the formatting and parsing functions in cpumask.h use nr_cpumask_bits like other cpumask functions; however, nr_cpumask_bits is either NR_CPUS or nr_cpu_ids depending on CONFIG_CPUMASK_OFFSTACK. This leads to inconsistent behaviors. With CONFIG_NR_CPUS=512 and !CONFIG_CPUMASK_OFFSTACK # cat /sys/devices/virtual/net/lo/queues/rx-0/rps_cpus 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000 # cat /proc/self/status | grep Cpus_allowed: Cpus_allowed: f With CONFIG_NR_CPUS=1024 and CONFIG_CPUMASK_OFFSTACK (fedora default) # cat /sys/devices/virtual/net/lo/queues/rx-0/rps_cpus 0 # cat /proc/self/status | grep Cpus_allowed: Cpus_allowed: f Note that /proc/self/status is always using nr_cpu_ids regardless of config. This is because seq cpumask formattings functions always use nr_cpu_ids. Given that the same output fields may switch between the two forms, converging on nr_cpu_ids always isn't too likely to surprise userland. This patch updates the formatting and parsing functions in cpumask.h to always use nr_cpu_ids. There's no point in dealing with CPUs which aren't even possible on the machine. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
f5ac1f55 |
|
12-Feb-2015 |
Rasmus Villemoes <linux@rasmusvillemoes.dk> |
linux/cpumask.h: update bitmap wrappers to take unsigned int Since the various bitmap_* functions now take an unsigned int as nbits parameter, it makes sense to also update the various wrappers, even though they're marked as obsolete. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
5aaba363 |
|
30-Sep-2014 |
Sudeep Holla <sudeep.holla@arm.com> |
cpumask: factor out show_cpumap into separate helper function Many sysfs *_show function use cpu{list,mask}_scnprintf to copy cpumap to the buffer aligned to PAGE_SIZE, append '\n' and '\0' to return null terminated buffer with newline. This patch creates a new helper function cpumap_print_to_pagebuf in cpumask.h using newly added bitmap_print_to_pagebuf and consolidates most of those sysfs functions using the new helper function. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Suggested-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: x86@kernel.org Cc: linux-acpi@vger.kernel.org Cc: linux-pci@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
#
4ba29684 |
|
26-Aug-2014 |
Christoph Lameter <cl@linux.com> |
percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t __get_cpu_var can paper over differences in the definitions of cpumask_var_t and either use the address of the cpumask variable directly or perform a fetch of the address of the struct cpumask allocated elsewhere. This is important particularly when using per cpu cpumask_var_t declarations because in one case we have an offset into a per cpu area to handle and in the other case we need to fetch a pointer from the offset. This patch introduces a new macro this_cpu_cpumask_var_ptr() that is defined where cpumask_var_t is defined and performs the proper actions. All use cases where __get_cpu_var is used with cpumask_var_t are converted to the use of this_cpu_cpumask_var_ptr(). Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
|
#
da91309e |
|
09-Jun-2014 |
Amir Vadai <amirv@mellanox.com> |
cpumask: Utility function to set n'th cpu - local cpu first This function sets the n'th cpu - local cpu's first. For example: in a 16 cores server with even cpu's local, will get the following values: cpumask_set_cpu_local_first(0, numa, cpumask) => cpu 0 is set cpumask_set_cpu_local_first(1, numa, cpumask) => cpu 2 is set ... cpumask_set_cpu_local_first(7, numa, cpumask) => cpu 14 is set cpumask_set_cpu_local_first(8, numa, cpumask) => cpu 1 is set cpumask_set_cpu_local_first(9, numa, cpumask) => cpu 3 is set ... cpumask_set_cpu_local_first(15, numa, cpumask) => cpu 15 is set Curently this function will be used by multi queue networking devices to calculate the irq affinity mask, such that as many local cpu's as possible will be utilized to handle the mq device irq's. Signed-off-by: Amir Vadai <amirv@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ee39facb |
|
01-Jun-2014 |
David S. Miller <davem@davemloft.net> |
net: Revert mlx4 cpumask changes. This reverts commit 70a640d0dae3a9b1b222ce673eb5d92c263ddd61 ("net/mlx4_en: Use affinity hint") and commit c8865b64b05b2f4eeefd369373e9c8aeb069e7a1 ("cpumask: Utility function to set n'th cpu - local cpu first") because these changes break the build when SMP is disabled amongst other things. Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
c8865b64 |
|
25-May-2014 |
Amir Vadai <amirv@mellanox.com> |
cpumask: Utility function to set n'th cpu - local cpu first This function sets the n'th cpu - local cpu's first. For example: in a 16 cores server with even cpu's local, will get the following values: cpumask_set_cpu_local_first(0, numa, cpumask) => cpu 0 is set cpumask_set_cpu_local_first(1, numa, cpumask) => cpu 2 is set ... cpumask_set_cpu_local_first(7, numa, cpumask) => cpu 14 is set cpumask_set_cpu_local_first(8, numa, cpumask) => cpu 1 is set cpumask_set_cpu_local_first(9, numa, cpumask) => cpu 3 is set ... cpumask_set_cpu_local_first(15, numa, cpumask) => cpu 15 is set Curently this function will be used by multi queue networking devices to calculate the irq affinity mask, such that as many local cpu's as possible will be utilized to handle the mq device irq's. Signed-off-by: Amir Vadai <amirv@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
cea092c9 |
|
13-May-2014 |
Brian W Hart <hartb@linux.vnet.ibm.com> |
cpumask.h: silence warning with -Wsign-compare Silence the warning when building with -Wsign-compare when cpumask.h is included: include/linux/cpumask.h: In function ‘cpumask_parse’: include/linux/cpumask.h:603:26: warning: signed and unsigned type in conditional expression [-Wsign-compare] int len = nl ? nl - buf : strlen(buf); ^ V2: Rusty pointed out that unsigned should be used instead. Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
ba630e49 |
|
12-Mar-2013 |
Tejun Heo <tj@kernel.org> |
cpumask: implement cpumask_parse() We have cpulist_parse() but not cpumask_parse(). Implement it using bitmap_parse(). bitmap_parse() is weird in that it takes @len for a string in kernel-memory which also is inconsistent with bitmap_parselist(). Make cpumask_parse() calculate the length and don't expose the inconsistency to cpumask users. Maybe we can fix up bitmap_parse() later. This will be used to expose workqueue cpumask knobs to userland via sysfs. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au>
|
#
231daf07 |
|
26-Jul-2012 |
Alex Shi <alex.shi@linux.alibaba.com> |
cpumask: cpulist_parse() comments correction As introduced in Rusty's commit 29c0177e6a4, the function has no parameter @len, so need to remove it from comments to avoid kernel-doc warning: alexs@debian:~/linux-next$ scripts/kernel-doc -man include/linux/cpumask.h | split-man.pl /tmp/man .... Warning(include/linux/cpumask.h:602): Excess function parameter 'len' description in 'cpulist_parse' and correct the function name in comments to cpulist_parse. Signed-off-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
c777ad69 |
|
28-May-2012 |
Alex Shi <alex.shi@linux.alibaba.com> |
cpumask: add a few comments of cpumask functions Current few cpumask functions' purposes are not quite clear. Stupid user like myself needs to dig into details for clear function purpose and return value. Add few explanation for them is helpful. Thanks for Srivatsa's comments and correction! Signed-off-by: Alex Shi <alex.shi@intel.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
615399c8 |
|
28-Mar-2012 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: remove old cpu_*_map. These are obsolete: cpu_*_mask provides (const) pointers. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
38b93780 |
|
28-Mar-2012 |
Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> |
lib/cpumask.c: remove __any_online_cpu() __any_online_cpu() is not optimal and also unnecessary. So, replace its use by faster cpumask_* operations. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
187f1882 |
|
23-Nov-2011 |
Paul Gortmaker <paul.gortmaker@windriver.com> |
BUG: headers with BUG/BUG_ON etc. need linux/bug.h If a header file is making use of BUG, BUG_ON, BUILD_BUG_ON, or any other BUG variant in a static inline (i.e. not in a #define) then that header really should be including <linux/bug.h> and not just expecting it to be implicitly present. We can make this change risk-free, since if the files using these headers didn't have exposure to linux/bug.h already, they would have been causing compile failures/warnings. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
#
a64a26e8 |
|
26-Jul-2011 |
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> |
cpumask: add cpumask_var_t documentation cpumask_var_t has one notable difference from cpumask_t. Add the explanation. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Thiago Farina <tfransosi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
4b060420 |
|
24-May-2011 |
Mike Travis <travis@sgi.com> |
bitmap, irq: add smp_affinity_list interface to /proc/irq Manually adjusting the smp_affinity for IRQ's becomes unwieldy when the cpu count is large. Setting smp affinity to cpus 256 to 263 would be: echo 000000ff,00000000,00000000,00000000,00000000,00000000,00000000,00000000 > smp_affinity instead of: echo 256-263 > smp_affinity_list Think about what it looks like for cpus around say, 4088 to 4095. We already have many alternate "list" interfaces: /sys/devices/system/cpu/cpuX/indexY/shared_cpu_list /sys/devices/system/cpu/cpuX/topology/thread_siblings_list /sys/devices/system/cpu/cpuX/topology/core_siblings_list /sys/devices/system/node/nodeX/cpulist /sys/devices/pci***/***/local_cpulist Add a companion interface, smp_affinity_list to use cpu lists instead of cpu maps. This conforms to other companion interfaces where both a map and a list interface exists. This required adding a bitmap_parselist_user() function in a manner similar to the bitmap_parse_user() function. [akpm@linux-foundation.org: make __bitmap_parselist() static] Signed-off-by: Mike Travis <travis@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jack Steiner <steiner@sgi.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
221e3ebf |
|
05-Mar-2010 |
Heiko Carstens <hca@linux.ibm.com> |
cpumask: let num_*_cpus() function always return unsigned values Dependent on CONFIG_SMP the num_*_cpus() functions return unsigned or signed values. Let them always return unsigned values to avoid strange casts. Fixes at least one warning: kernel/kprobes.c: In function 'register_kretprobe': kernel/kprobes.c:1038: warning: comparison of distinct pointer types lacks a cast Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
8bd93a2c |
|
22-Feb-2010 |
Paul E. McKenney <paulmck@kernel.org> |
rcu: Accelerate grace period if last non-dynticked CPU Currently, rcu_needs_cpu() simply checks whether the current CPU has an outstanding RCU callback, which means that the last CPU to go into dyntick-idle mode might wait a few ticks for the relevant grace periods to complete. However, if all the other CPUs are in dyntick-idle mode, and if this CPU is in a quiescent state (which it is for RCU-bh and RCU-sched any time that we are considering going into dyntick-idle mode), then the grace period is instantly complete. This patch therefore repeatedly invokes the RCU grace-period machinery in order to force any needed grace periods to complete quickly. It does so a limited number of times in order to prevent starvation by an RCU callback function that might pass itself to call_rcu(). However, if any CPU other than the current one is not in dyntick-idle mode, fall back to simply checking (with fix to bug noted by Lai Jiangshan). Also, take advantage of last grace-period forcing, the opportunity to do so noted by Steve Rostedt. And apply simplified #ifdef condition suggested by Frederic Weisbecker. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-15-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
6ad4c188 |
|
25-Nov-2009 |
Peter Zijlstra <a.p.zijlstra@chello.nl> |
sched: Fix balance vs hotplug race Since (e761b77: cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment) we have cpu_active_mask which is suppose to rule scheduler migration and load-balancing, except it never (fully) did. The particular problem being solved here is a crash in try_to_wake_up() where select_task_rq() ends up selecting an offline cpu because select_task_rq_fair() trusts the sched_domain tree to reflect the current state of affairs, similarly select_task_rq_rt() trusts the root_domain. However, the sched_domains are updated from CPU_DEAD, which is after the cpu is taken offline and after stop_machine is done. Therefore it can race perfectly well with code assuming the domains are right. Cure this by building the domains from cpu_active_mask on CPU_DOWN_PREPARE. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
6ba2ef7b |
|
24-Sep-2009 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: Move deprecated functions to end of header. The new ones have pretty kerneldoc. Move the old ones to the end to avoid confusing people. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: benh@kernel.crashing.org
|
#
4b805b17 |
|
24-Sep-2009 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: remove unused deprecated functions, avoid accusations of insanity We're not forcing removal of the old cpu_ functions, but we might as well delete the now-unused ones. Especially CPUMASK_ALLOC and friends. I actually got a phone call (!) from a hacker who thought I had introduced them as the new cpumask API. He seemed bewildered that I had lost all taste. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: benh@kernel.crashing.org
|
#
72d78d05 |
|
24-Sep-2009 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: remove unused cpu_mask_all It's only defined for NR_CPUS > BITS_PER_LONG; cpu_all_mask is always defined (and const). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
a0219d94 |
|
24-Sep-2009 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: remove dangerous CPU_MASK_ALL_PTR (Thanks to Al Viro for reminding me of this, via Ingo) CPU_MASK_ALL is the (deprecated) "all bits set" cpumask, defined as so: #define CPU_MASK_ALL (cpumask_t) { { ... } } Taking the address of such a temporary is questionable at best, unfortunately 321a8e9d (cpumask: add CPU_MASK_ALL_PTR macro) added CPU_MASK_ALL_PTR: #define CPU_MASK_ALL_PTR (&CPU_MASK_ALL) Which formalizes this practice. One day gcc could bite us over this usage (though we seem to have gotten away with it so far). Now all callers are removed, we kill it. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Ingo Molnar <mingo@elte.hu> Reported-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Mike Travis <travis@sgi.com>
|
#
54fdade1 |
|
22-Sep-2009 |
Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> |
generic-ipi: make struct call_function_data lockless This patch can remove spinlock from struct call_function_data, the reasons are below: 1: add a new interface for cpumask named cpumask_test_and_clear_cpu(), it can atomically test and clear specific cpu, we can use it instead of cpumask_test_cpu() and cpumask_clear_cpu() and no need data->lock to protect those in generic_smp_call_function_interrupt(). 2: in smp_call_function_many(), after csd_lock() return, the current's cfd_data is deleted from call_function list, so it not have race between other cpus, then cfs_data is only used in smp_call_function_many() that must disable preemption and not from a hardware interrupthandler or from a bottom half handler to call, only the correspond cpu can use it, so it not have race in current cpu, no need cfs_data->lock to protect it. 3: after 1 and 2, cfs_data->lock is only use to protect cfs_data->refs in generic_smp_call_function_interrupt(), so we can define cfs_data->refs to atomic_t, and no need cfs_data->lock any more. Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Peter Zijlstra <peterz@infradead.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> [akpm@linux-foundation.org: use atomic_dec_return()] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
f4b0373b |
|
21-Aug-2009 |
Linus Torvalds <torvalds@linux-foundation.org> |
Make bitmask 'and' operators return a result code When 'and'ing two bitmasks (where 'andnot' is a variation on it), some cases want to know whether the result is the empty set or not. In particular, the TLB IPI sending code wants to do cpumask operations and determine if there are any CPU's left in the final set. So this just makes the bitmask (and cpumask) functions return a boolean for whether the result has any bits set. Cc: stable@kernel.org (2.6.30, needed by TLB shootdown fix) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
0281b5dc |
|
06-Jun-2009 |
Yinghai Lu <yinghai@kernel.org> |
cpumask: introduce zalloc_cpumask_var So can get cpumask_var with cpumask_clear Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
8c384cde |
|
31-Dec-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS Impact: new debug CONFIG options This helps find unconverted code. It currently breaks compile horribly, but we never wanted a flag day so that's expected. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
3fa41520 |
|
29-Dec-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: make set_cpu_*/init_cpu_* out-of-line They're only for use in boot/cpu hotplug code anyway, and this avoids the use of deprecated cpu_*_map. Stephen Rothwell points out that gcc 4.2.4 (on powerpc at least) didn't like the cast away of const anyway: include/linux/cpumask.h: In function 'set_cpu_possible': include/linux/cpumask.h:1052: warning: passing argument 2 of 'cpumask_set_cpu' discards qualifiers from pointer target type So this kills two birds with one stone. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
ae7a47e7 |
|
29-Dec-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: make cpumask.h eat its own dogfood. Changes: 1) cpumask_t to struct cpumask, 2) cpus_weight_nr to cpumask_weight, 3) cpu_isset to cpumask_test_cpu, 4) ->bits to cpumask_bits() 5) cpu_*_map to cpu_*_mask. 6) for_each_cpu_mask_nr to for_each_cpu Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
b3199c02 |
|
29-Dec-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: switch over to cpu_online/possible/active/present_mask: core Impact: cleanup This implements the obsolescent cpu_online_map in terms of cpu_online_mask, rather than the other way around. Same for the other maps. The documentation comments are also updated to refer to _mask rather than _map. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Mike Travis <travis@sgi.com>
|
#
7b4967c5 |
|
18-Dec-2008 |
Mike Travis <travis@sgi.com> |
cpumask: Add alloc_cpumask_var_node() Impact: New API This will be needed in x86 code to allocate the domain and old_domain cpumasks on the same node as where the containing irq_cfg struct is allocated. (Also fixes double-dump_stack on rare CONFIG_DEBUG_PER_CPU_MAPS case) Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (re-impl alloc_cpumask_var)
|
#
7be75853 |
|
13-Dec-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: Use all NR_CPUS bits unless CONFIG_CPUMASK_OFFSTACK Impact: futureproof as we convert more code to new APIs The old cpumask operators treat all NR_CPUS bits as relevent, the new ones use nr_cpumask_bits. For large NR_CPUS and small nr_cpu_ids, this makes a difference. However, mixing the two can cause problems with undefined bits. An arch which sets CONFIG_CPUMASK_OFFSTACK should have converted across to the new operators, so it's safe in that case. (Thanks to Stephen Rothwell for bisecting the initial unused-bits bug, and Mike Travis for this solution). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Mike Travis <travis@sgi.com>
|
#
29c0177e |
|
13-Dec-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: change cpumask_scnprintf, cpumask_parse_user, cpulist_parse, and cpulist_scnprintf to take pointers. Impact: change calling convention of existing cpumask APIs Most cpumask functions started with cpus_: these have been replaced by cpumask_ ones which take struct cpumask pointers as expected. These four functions don't have good replacement names; fortunately they're rarely used, so we just change them over. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Mike Travis <travis@sgi.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: paulus@samba.org Cc: mingo@redhat.com Cc: tony.luck@intel.com Cc: ralf@linux-mips.org Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: cl@linux-foundation.org Cc: srostedt@redhat.com
|
#
984f2f37 |
|
08-Nov-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: introduce new API, without changing anything, v3 Impact: cleanup Clean up based on feedback from Andrew Morton and others: - change to inline functions instead of macros - add __init to bootmem method - add a missing debug check Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
cd83e42c |
|
06-Nov-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: new API, v2 - add cpumask_of() - add free_bootmem_cpumask_var() Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
2d3854a3 |
|
04-Nov-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: introduce new API, without changing anything Impact: introduce new APIs We want to deprecate cpumasks on the stack, as we are headed for gynormous numbers of CPUs. Eventually, we want to head towards an undefined 'struct cpumask' so they can never be declared on stack. 1) New cpumask functions which take pointers instead of copies. (cpus_* -> cpumask_*) 2) Several new helpers to reduce requirements for temporary cpumasks (cpumask_first_and, cpumask_next_and, cpumask_any_and) 3) Helpers for declaring cpumasks on or offstack for large NR_CPUS (cpumask_var_t, alloc_cpumask_var and free_cpumask_var) 4) 'struct cpumask' for explicitness and to mark new-style code. 5) Make iterator functions stop at nr_cpu_ids (a runtime constant), not NR_CPUS for time efficiency and for smaller dynamic allocations in future. 6) cpumask_copy() so we can allocate less than a full cpumask eventually (for alloc_cpumask_var), and so we can eliminate the 'struct cpumask' definition eventually. 7) work_on_cpu() helper for doing task on a CPU, rather than saving old cpumask for current thread and manipulating it. 8) smp_call_function_many() which is smp_call_function_mask() except taking a cpumask pointer. Note that this patch simply introduces the new functions and leaves the obsolescent ones in place. This is to simplify the transition patches. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
3dd730f2 |
|
29-Jul-2008 |
Stephen Rothwell <sfr@canb.auug.org.au> |
cpumask: statement expressions confuse some versions of gcc when you take the address of the result. Noticed on a sparc64 compile using a version 3.4.5 cross compiler. kernel/time/tick-common.c: In function `tick_check_new_device': kernel/time/tick-common.c:210: error: invalid lvalue in unary `&' ... Just make it a regular expression. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
e56b3bc7 |
|
28-Jul-2008 |
Linus Torvalds <torvalds@linux-foundation.org> |
cpu masks: optimize and clean up cpumask_of_cpu() Clean up and optimize cpumask_of_cpu(), by sharing all the zero words. Instead of stupidly generating all possible i=0...NR_CPUS 2^i patterns creating a huge array of constant bitmasks, realize that the zero words can be shared. In other words, on a 64-bit architecture, we only ever need 64 of these arrays - with a different bit set in one single world (with enough zero words around it so that we can create any bitmask by just offsetting in that big array). And then we just put enough zeroes around it that we can point every single cpumask to be one of those things. So when we have 4k CPU's, instead of having 4k arrays (of 4k bits each, with one bit set in each array - 2MB memory total), we have exactly 64 arrays instead, each 8k bits in size (64kB total). And then we just point cpumask(n) to the right position (which we can calculate dynamically). Once we have the right arrays, getting "cpumask(n)" ends up being: static inline const cpumask_t *get_cpu_mask(unsigned int cpu) { const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; p -= cpu / BITS_PER_LONG; return (const cpumask_t *)p; } This brings other advantages and simplifications as well: - we are not wasting memory that is just filled with a single bit in various different places - we don't need all those games to re-create the arrays in some dense format, because they're already going to be dense enough. if we compile a kernel for up to 4k CPU's, "wasting" that 64kB of memory is a non-issue (especially since by doing this "overlapping" trick we probably get better cache behaviour anyway). [ mingo@elte.hu: Converted Linus's mails into a commit. See: http://lkml.org/lkml/2008/7/27/156 http://lkml.org/lkml/2008/7/28/320 Also applied a family filter - which also has the side-effect of leaving out the bits where Linus calls me an idio... Oh, never mind ;-) ] Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
b8d317d1 |
|
24-Jul-2008 |
Mike Travis <travis@sgi.com> |
cpumask: make cpumask_of_cpu_map generic If an arch doesn't define cpumask_of_cpu_map, create a generic statically-initialized one for them. This allows removal of the buggy cpumask_of_cpu() macro (&cpumask_of_cpu() gives address of out-of-scope var). An arch with NR_CPUS of 4096 probably wants to allocate this itself based on the actual number of CPUs, since otherwise they're using 2MB of rodata (1024 cpus means 128k). That's what CONFIG_HAVE_CPUMASK_OF_CPU_MAP is for (only x86/64 does so at the moment). In future as we support more CPUs, we'll need to resort to a get_cpu_map()/put_cpu_map() allocation scheme. Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jack Steiner <steiner@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
80422d34 |
|
18-Jul-2008 |
Mike Travis <travis@sgi.com> |
cpumask: Provide a generic set of CPUMASK_ALLOC macros, FIXUP * Rename CPUMASK_VAR --> CPUMASK_PTR (and simplify) * Fix a semantic error in CPUMASK_ALLOC * Add a bit of commentry to cpumask.h Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
77586c2b |
|
15-Jul-2008 |
Mike Travis <travis@sgi.com> |
cpumask: Provide a generic set of CPUMASK_ALLOC macros * Provide a generic set of CPUMASK_ALLOC macros patterned after the SCHED_CPUMASK_ALLOC macros. This is used where multiple cpumask_t variables are declared on the stack to reduce the amount of stack space required. Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
65c01184 |
|
15-Jul-2008 |
Mike Travis <travis@sgi.com> |
cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr * This patch replaces the dangerous lvalue version of cpumask_of_cpu with new cpumask_of_cpu_ptr macros. These are patterned after the node_to_cpumask_ptr macros. In general terms, if there is a cpumask_of_cpu_map[] then a pointer to the cpumask_of_cpu_map[cpu] entry is used. The cpumask_of_cpu_map is provided when there is a large NR_CPUS count, reducing greatly the amount of code generated and stack space used for cpumask_of_cpu(). The pointer to the cpumask_t value is needed for calling set_cpus_allowed_ptr() to reduce the amount of stack space needed to pass the cpumask_t value. If there isn't a cpumask_of_cpu_map[], then a temporary variable is declared and filled in with value from cpumask_of_cpu(cpu) as well as a pointer variable pointing to this temporary variable. Afterwards, the pointer is used to reference the cpumask value. The compiler will optimize out the extra dereference through the pointer as well as the stack space used for the pointer, resulting in identical code. A good example of the orthogonal usages is in net/sunrpc/svc.c: case SVC_POOL_PERCPU: { unsigned int cpu = m->pool_to[pidx]; cpumask_of_cpu_ptr(cpumask, cpu); *oldmask = current->cpus_allowed; set_cpus_allowed_ptr(current, cpumask); return 1; } case SVC_POOL_PERNODE: { unsigned int node = m->pool_to[pidx]; node_to_cpumask_ptr(nodecpumask, node); *oldmask = current->cpus_allowed; set_cpus_allowed_ptr(current, nodecpumask); return 1; } Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
e761b772 |
|
15-Jul-2008 |
Max Krasnyansky <maxk@qualcomm.com> |
cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment (take 2) This is based on Linus' idea of creating cpu_active_map that prevents scheduler load balancer from migrating tasks to the cpu that is going down. It allows us to simplify domain management code and avoid unecessary domain rebuilds during cpu hotplug event handling. Please ignore the cpusets part for now. It needs some more work in order to avoid crazy lock nesting. Although I did simplfy and unify domain reinitialization logic. We now simply call partition_sched_domains() in all the cases. This means that we're using exact same code paths as in cpusets case and hence the test below cover cpusets too. Cpuset changes to make rebuild_sched_domains() callable from various contexts are in the separate patch (right next after this one). This not only boots but also easily handles while true; do make clean; make -j 8; done and while true; do on-off-cpu 1; done at the same time. (on-off-cpu 1 simple does echo 0/1 > /sys/.../cpu1/online thing). Suprisingly the box (dual-core Core2) is quite usable. In fact I'm typing this on right now in gnome-terminal and things are moving just fine. Also this is running with most of the debug features enabled (lockdep, mutex, etc) no BUG_ONs or lockdep complaints so far. I believe I addressed all of the Dmitry's comments for original Linus' version. I changed both fair and rt balancer to mask out non-active cpus. And replaced cpu_is_offline() with !cpu_active() in the main scheduler code where it made sense (to me). Signed-off-by: Max Krasnyanskiy <maxk@qualcomm.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Gregory Haskins <ghaskins@novell.com> Cc: dmitry.adamushko@gmail.com Cc: pj@sgi.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
9982fbfa |
|
06-Jul-2008 |
Ingo Molnar <mingo@elte.hu> |
Revert "cpumask: introduce new APIs" This reverts commit acb7669c125676e63cf96582455509216c39745e. the wrappers are not needed anymore. Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
acb7669c |
|
04-Jul-2008 |
Stephen Rothwell <sfr@canb.auug.org.au> |
cpumask: introduce new APIs In linux-next there is a commit ("x86: Add performance variants of cpumask operators") which, as part of the 4096 cpu support work adds some new APIs for dealing with cpu masks. Add trivial versions of these now so that subsystems can update in a timely manner and avoid conflicts in linux-next and the next merge window. Cc: Mike Travis <travis@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
7baac8b9 |
|
13-May-2008 |
Alexander van Heukelum <heukelum@mailshack.com> |
cpumask: make for_each_cpu_mask a bit smaller The for_each_cpu_mask loop is used quite often in the kernel. It makes use of two functions: first_cpu and next_cpu. This patch changes for_each_cpu_mask to use only the latter. Because next_cpu finds the next eligible cpu _after_ the given one, the iteration variable has to be initialized to -1 and next_cpu has to be called with this value before the first iteration. An x86_64 defconfig kernel (from sched/latest) is about 2500 bytes smaller with this patch applied: text data bss dec hex filename 6222517 917952 749932 7890401 7865e1 vmlinux.orig 6219922 917952 749932 7887806 785bbe vmlinux The same size reduction is seen for defconfig+MAXSMP text data bss dec hex filename 6241772 2563968 1492716 10298456 9d2458 vmlinux.orig 6239211 2563968 1492716 10295895 9d1a57 vmlinux Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
#
41df0d61 |
|
12-May-2008 |
Mike Travis <travis@sgi.com> |
x86: Add performance variants of cpumask operators * Increase performance for systems with large count NR_CPUS by limiting the range of the cpumask operators that loop over the bits in a cpumask_t variable. This removes a large amount of wasted cpu cycles. * Add performance variants of the cpumask operators: int cpus_weight_nr(mask) Same using nr_cpu_ids instead of NR_CPUS int first_cpu_nr(mask) Number lowest set bit, or nr_cpu_ids int next_cpu_nr(cpu, mask) Next cpu past 'cpu', or nr_cpu_ids for_each_cpu_mask_nr(cpu, mask) for-loop cpu over mask using nr_cpu_ids * Modify following to use performance variants: #define num_online_cpus() cpus_weight_nr(cpu_online_map) #define num_possible_cpus() cpus_weight_nr(cpu_possible_map) #define num_present_cpus() cpus_weight_nr(cpu_present_map) #define for_each_possible_cpu(cpu) for_each_cpu_mask_nr((cpu), ...) #define for_each_online_cpu(cpu) for_each_cpu_mask_nr((cpu), ...) #define for_each_present_cpu(cpu) for_each_cpu_mask_nr((cpu), ...) * Comment added to include/linux/cpumask.h: Note: The alternate operations with the suffix "_nr" are used to limit the range of the loop to nr_cpu_ids instead of NR_CPUS when NR_CPUS > 64 for performance reasons. If NR_CPUS is <= 64 then most assembler bitmask operators execute faster with a constant range, so the operator will continue to use NR_CPUS. Another consideration is that nr_cpu_ids is initialized to NR_CPUS and isn't lowered until the possible cpus are discovered (including any disabled cpus). So early uses will span the entire range of NR_CPUS. (The net effect is that for systems with 64 or less CPU's there are no functional changes.) For inclusion into sched-devel/latest tree. Based on: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git + sched-devel/latest .../mingo/linux-2.6-sched-devel.git Cc: Paul Jackson <pj@sgi.com> Cc: Christoph Lameter <clameter@sgi.com> Reviewed-by: Paul Jackson <pj@sgi.com> Reviewed-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
f4ed0dea |
|
12-May-2008 |
Paul Jackson <pj@sgi.com> |
cpumask: remove bitmap_scnprintf_len and cpumask_scnprintf_len They aren't used. They were briefly used as part of some other patches to provide an alternative format for displaying some /proc and /sys cpumasks. They probably should have been removed when those other patches were dropped, in favor of a different solution. Signed-off-by: Paul Jackson <pj@sgi.com> Cc: "Mike Travis" <travis@sgi.com> Cc: "Bert Wesarg" <bert.wesarg@googlemail.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
7ea931c9 |
|
28-Apr-2008 |
Paul Jackson <pj@sgi.com> |
mempolicy: add bitmap_onto() and bitmap_fold() operations The following adds two more bitmap operators, bitmap_onto() and bitmap_fold(), with the usual cpumask and nodemask wrappers. The bitmap_onto() operator computes one bitmap relative to another. If the n-th bit in the origin mask is set, then the m-th bit of the destination mask will be set, where m is the position of the n-th set bit in the relative mask. The bitmap_fold() operator folds a bitmap into a second that has bit m set iff the input bitmap has some bit n set, where m == n mod sz, for the specified sz value. There are two substantive changes between this patch and its predecessor bitmap_relative: 1) Renamed bitmap_relative() to be bitmap_onto(). 2) Added bitmap_fold(). The essential motivation for bitmap_onto() is to provide a mechanism for converting a cpuset-relative CPU or Node mask to an absolute mask. Cpuset relative masks are written as if the current task were in a cpuset whose CPUs or Nodes were just the consecutive ones numbered 0..N-1, for some N. The bitmap_onto() operator is provided in anticipation of adding support for the first such cpuset relative mask, by the mbind() and set_mempolicy() system calls, using a planned flag of MPOL_F_RELATIVE_NODES. These bitmap operators (and their nodemask wrappers, in particular) will be used in code that converts the user specified cpuset relative memory policy to a specific system node numbered policy, given the current mems_allowed of the tasks cpuset. Such cpuset relative mempolicies will address two deficiencies of the existing interface between cpusets and mempolicies: 1) A task cannot at present reliably establish a cpuset relative mempolicy because there is an essential race condition, in that the tasks cpuset may be changed in between the time the task can query its cpuset placement, and the time the task can issue the applicable mbind or set_memplicy system call. 2) A task cannot at present establish what cpuset relative mempolicy it would like to have, if it is in a smaller cpuset than it might have mempolicy preferences for, because the existing interface only allows specifying mempolicies for nodes currently allowed by the cpuset. Cpuset relative mempolicies are useful for tasks that don't distinguish particularly between one CPU or Node and another, but only between how many of each are allowed, and the proper placement of threads and memory pages on the various CPUs and Nodes available. The motivation for the added bitmap_fold() can be seen in the following example. Let's say an application has specified some mempolicies that presume 16 memory nodes, including say a mempolicy that specified MPOL_F_RELATIVE_NODES (cpuset relative) nodes 12-15. Then lets say that application is crammed into a cpuset that only has 8 memory nodes, 0-7. If one just uses bitmap_onto(), this mempolicy, mapped to that cpuset, would ignore the requested relative nodes above 7, leaving it empty of nodes. That's not good; better to fold the higher nodes down, so that some nodes are included in the resulting mapped mempolicy. In this case, the mempolicy nodes 12-15 are taken modulo 8 (the weight of the mems_allowed of the confining cpuset), resulting in a mempolicy specifying nodes 4-7. Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: David Rientjes <rientjes@google.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Andi Kleen <ak@suse.de> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: <kosaki.motohiro@jp.fujitsu.com> Cc: <ray-lk@madrabbit.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
9f0e8d04 |
|
04-Apr-2008 |
Mike Travis <travis@sgi.com> |
x86: convert cpumask_of_cpu macro to allocated array * Here is a simple patch to use an allocated array of cpumasks to represent cpumask_of_cpu() instead of constructing one on the stack. It's based on the Kconfig option "HAVE_CPUMASK_OF_CPU_MAP" which is currently only set for x86_64 SMP. Otherwise the the existing cpumask_of_cpu() is used but has been changed to produce an lvalue so a pointer to it can be used. Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
321a8e9d |
|
04-Apr-2008 |
Mike Travis <travis@sgi.com> |
cpumask: add CPU_MASK_ALL_PTR macro * Add a static cpumask_t variable "CPU_MASK_ALL_PTR" to use as a pointer reference to CPU_MASK_ALL. This reduces where possible the instances where CPU_MASK_ALL allocates and fills a large array on the stack. Used only if NR_CPUS > BITS_PER_LONG. * Change init/main.c to use new set_cpus_allowed_ptr(). Depends on: [sched-devel]: sched: add new set_cpus_allowed_ptr function Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
30ca60c1 |
|
25-Mar-2008 |
Mike Travis <travis@sgi.com> |
cpumask: add cpumask_scnprintf_len function Add a new function cpumask_scnprintf_len() to return the number of characters needed to display "len" cpumask bits. The current method of allocating NR_CPUS bytes is incorrect as what's really needed is 9 characters per 32-bit word of cpumask bits (8 hex digits plus the seperator [','] or the terminating NULL.) This function provides the caller the means to allocate the correct string length. Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
#
23551885 |
|
30-Jan-2008 |
Ingo Molnar <mingo@elte.hu> |
x86: avoid build warning fix this build warning: include/asm/topology_32.h: In function 'node_to_first_cpu': include/asm/topology_32.h:66: warning: unused variable 'mask' Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
#
a263898f |
|
30-Dec-2007 |
Ingo Molnar <mingo@elte.hu> |
CPU hotplug: fix cpu_is_offline() on !CONFIG_HOTPLUG_CPU make randconfig bootup testing found that the cpufreq code crashes on bootup, if the powernow-k8 driver is enabled and if maxcpus=1 passed on the boot line to a !CONFIG_HOTPLUG_CPU kernel. First lockdep found out that there's an inconsistent unlock sequence: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- swapper/1 is trying to release lock (&per_cpu(cpu_policy_rwsem, cpu)) at: [<ffffffff806ffd8e>] unlock_policy_rwsem_write+0x3c/0x42 but there are no more locks to release! Call Trace: [<ffffffff806ffd8e>] unlock_policy_rwsem_write+0x3c/0x42 [<ffffffff80251c29>] print_unlock_inbalance_bug+0x104/0x12c [<ffffffff80252f3a>] mark_held_locks+0x56/0x94 [<ffffffff806ffd8e>] unlock_policy_rwsem_write+0x3c/0x42 [<ffffffff807008b6>] cpufreq_add_dev+0x2a8/0x5c4 ... then shortly afterwards the cpufreq code crashed on an assert: ------------[ cut here ]------------ kernel BUG at drivers/cpufreq/cpufreq.c:1068! invalid opcode: 0000 [1] SMP [...] Call Trace: [<ffffffff805145d6>] sysdev_driver_unregister+0x5b/0x91 [<ffffffff806ff520>] cpufreq_register_driver+0x15d/0x1a2 [<ffffffff80cc0596>] powernowk8_init+0x86/0x94 [...] ---[ end trace 1e9219be2b4431de ]--- the bug was caused by maxcpus=1 bootup, which brought up the secondary core as !cpu_online() but !cpu_is_offline() either, which on on !CONFIG_HOTPLUG_CPU is always 0 (include/linux/cpu.h): /* CPUs don't go offline once they're online w/o CONFIG_HOTPLUG_CPU */ static inline int cpu_is_offline(int cpu) { return 0; } but the cpufreq code uses cpu_online() and cpu_is_offline() in a mixed way - the low-level drivers use cpu_online(), while the cpufreq core uses cpu_is_offline(). This opened up the possibility to add the non-initialized sysdev device of the secondary core: cpufreq-core: trying to register driver powernow-k8 cpufreq-core: adding CPU 0 powernow-k8: BIOS error - no PSB or ACPI _PSS objects cpufreq-core: initialization failed cpufreq-core: adding CPU 1 cpufreq-core: initialization failed which then blew up. The fix is to make cpu_is_offline() always the negation of cpu_online(). With that fix applied the kernel boots up fine without crashing: Calling initcall 0xffffffff80cc0510: powernowk8_init+0x0/0x94() powernow-k8: Found 1 AMD Athlon(tm) 64 X2 Dual Core Processor 3800+ processors (1 cpu cores) (version 2.20.00) powernow-k8: BIOS error - no PSB or ACPI _PSS objects initcall 0xffffffff80cc0510: powernowk8_init+0x0/0x94() returned -19. initcall 0xffffffff80cc0510 ran for 19 msecs: powernowk8_init+0x0/0x94() Calling initcall 0xffffffff80cc328f: init_lapic_nmi_sysfs+0x0/0x39() We could fix this by making CPU enumeration aware of max_cpus, but that would be more fragile IMO, and the cpu_online(cpu) != cpu_is_offline(cpu) possibility was quite confusing and a continuous source of bugs too. Most distributions have kernels with CPU hotplug enabled, so this bug remained hidden for a long time. Bug forensics: The broken cpu_is_offline() API variant was introduced via: commit a59d2e4e6977e7b94e003c96a41f07e96cddc340 Author: Rusty Russell <rusty@rustcorp.com.au> Date: Mon Mar 8 06:06:03 2004 -0800 [PATCH] minor cleanups for hotplug CPUs ( this predates linux-2.6.git, this commit is available from Thomas's historic git tree. ) Then 1.5 years later the cpufreq code made use of it: commit c32b6b8e524d2c337767d312814484d9289550cf Author: Ashok Raj <ashok.raj@intel.com> Date: Sun Oct 30 14:59:54 2005 -0800 [PATCH] create and destroy cpufreq sysfs entries based on cpu notifiers + if (cpu_is_offline(cpu)) + return 0; which is a correct use of the subtly broken new API. v2.6.15 then shipped with this bug included. then it took two more years for random-kernel qa to hit it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
53b8a315 |
|
20-Feb-2007 |
Christoph Lameter <clameter@sgi.com> |
[PATCH] Convert highest_possible_processor_id to nr_cpu_ids We frequently need the maximum number of possible processors in order to allocate arrays for all processors. So far this was done using highest_possible_processor_id(). However, we do need the number of processors not the highest id. Moreover the number was so far dynamically calculated on each invokation. The number of possible processors does not change when the system is running. We can therefore calculate that number once. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Frederik Deweerdt <frederik.deweerdt@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
01a3ee2b |
|
11-Oct-2006 |
Reinette Chatre <reinette.chatre@linux.intel.com> |
[PATCH] bitmap: parse input from kernel and user buffers lib/bitmap.c:bitmap_parse() is a library function that received as input a user buffer. This seemed to have originated from the way the write_proc function of the /proc filesystem operates. This has been reworked to not use kmalloc and eliminates a lot of get_user() overhead by performing one access_ok before using __get_user(). We need to test if we are in kernel or user space (is_user) and access the buffer differently. We cannot use __get_user() to access kernel addresses in all cases, for example in architectures with separate address space for kernel and user. This function will be useful for other uses as well; for example, taking input for /sysfs instead of /proc, so it was changed to accept kernel buffers. We have this use for the Linux UWB project, as part as the upcoming bandwidth allocator code. Only a few routines used this function and they were changed too. Signed-off-by: Reinette Chatre <reinette.chatre@linux.intel.com> Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Cc: Paul Jackson <pj@sgi.com> Cc: Joe Korty <joe.korty@ccur.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
9de9adb6 |
|
25-Jun-2006 |
Andrew Morton <akpm@osdl.org> |
[PATCH] for_each_cpu_mask() warning fix On UP, this: cpumask_t mask = node_to_cpumask(numa_node_id()); for_each_cpu_mask(cpu, mask) does this: mm/readahead.c: In function `node_readahead_aging': mm/readahead.c:850: warning: unused variable `mask' which is unpleasantly fixed by this: Acked-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
fb1bb34d |
|
25-Jun-2006 |
Andrew Morton <akpm@osdl.org> |
[PATCH] remove for_each_cpu() Convert a few stragglers over to for_each_possible_cpu(), remove for_each_cpu(). Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
631d6747 |
|
28-Mar-2006 |
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> |
[PATCH] for_each_possible_cpu: defines for_each_possible_cpu for_each_cpu() is a for-loop over cpu_possible_map. for_each_online_cpu is for-loop cpu over cpu_online_map. .....for_each_cpu() is not sufficiently explicit and can lead to mistakes. This patch adds for_each_possible_cpu() in preparation for the removal of for_each_cpu(). Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
96a9b4d3 |
|
25-Mar-2006 |
Andrew Morton <akpm@osdl.org> |
[PATCH] cpumask: uninline any_online_cpu() text data bss dec hex filename before: 3605597 1363528 363328 5332453 515de5 vmlinux after: 3605295 1363612 363200 5332107 515c8b vmlinux 218 bytes saved. Also, optimise any_online_cpu() out of existence on CONFIG_SMP=n. This function seems inefficient. Can't we simply AND the two masks, then use find_first_bit()? Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
86302820 |
|
25-Mar-2006 |
Andrew Morton <akpm@osdl.org> |
[PATCH] cpumask: uninline highest_possible_processor_id() Shrinks the only caller (net/bridge/netfilter/ebtables.c) by 174 bytes. Also, optimise highest_possible_processor_id() out of existence on CONFIG_SMP=n. Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
3d18bd74 |
|
25-Mar-2006 |
Andrew Morton <akpm@osdl.org> |
[PATCH] cpumask: uninline next_cpu() text data bss dec hex filename before: 3488027 1322496 360128 5170651 4ee5db vmlinux after: 3485112 1322480 359968 5167560 4ed9c8 vmlinux 2931 bytes saved Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
ccb46000 |
|
25-Mar-2006 |
Andrew Morton <akpm@osdl.org> |
[PATCH] cpumask: uninline first_cpu() text data bss dec hex filename before: 3490577 1322408 360000 5172985 4eeef9 vmlinux after: 3488027 1322496 360128 5170651 4ee5db vmlinux Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
7a8ef1cb |
|
10-Feb-2006 |
Andrew Morton <akpm@osdl.org> |
[PATCH] x86: don't initialise cpu_possible_map to all ones Initialising cpu_possible_map to all-ones with CONFIG_HOTPLUG_CPU means that a) All for_each_cpu() loops will iterate across all NR_CPUS CPUs, rather than over possible ones. That can be quite expensive. b) Soon we'll be allocating per-cpu areas only for possible CPUs. So with CPU_MASK_ALL, we'll be wasting memory. I also switched voyager over to not use CPU_MASK_ALL in the non-CPU-hotplug case. Should be OK.. I note that parisc is also using CPU_MASK_ALL. Suggest that it stop doing that. Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Paul Jackson <pj@sgi.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Zwane Mwaikambo <zwane@linuxpower.ca> Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
1b862354 |
|
14-Dec-2005 |
Al Viro <viro@zeniv.linux.org.uk> |
[PATCH] remove bogus asm/bug.h includes. A bunch of asm/bug.h includes are both not needed (since it will get pulled anyway) and bogus (since they are done too early). Removed. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
fb5eeeee |
|
30-Oct-2005 |
Paul Jackson <pj@sgi.com> |
[PATCH] cpusets: bitmap and mask remap operators In the forthcoming task migration support, a key calculation will be mapping cpu and node numbers from the old set to the new set while preserving cpuset-relative offset. For example, if a task and its pages on nodes 8-11 are being migrated to nodes 24-27, then pages on node 9 (the 2nd node in the old set) should be moved to node 25 (the 2nd node in the new set.) As with other bitmap operations, the proper way to code this is to provide the underlying calculation in lib/bitmap.c, and then to provide the usual cpumask and nodemask wrappers. This patch provides that. These operations are termed 'remap' operations. Both remapping a single bit and a set of bits is supported. Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
|
#
688ce17b |
|
16-Oct-2005 |
Al Viro <viro@zeniv.linux.org.uk> |
[PATCH]: highest_possible_processor_id() has to be a macro ... otherwise, things like alpha and sparc64 break and break badly. They define cpu_possible_map to something else in smp.h *AFTER* having included cpumask.h. If that puppy is a macro, expansion will happen at the actual caller, when we'd already seen #define cpu_possible_map ... and we will get the right thing used. As an inline helper it will be tokenized before we get to that define and that's it; no matter what we define later, it won't affect anything. We get modules with dependency on cpu_possible_map instead of the right symbol (phys_cpu_present_map in case of sparc64), or outright link errors if they are built-in. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
c8923c6b |
|
13-Oct-2005 |
David S. Miller <davem@davemloft.net> |
[NETFILTER]: Fix OOPSes on machines with discontiguous cpu numbering. Original patch by Harald Welte, with feedback from Herbert Xu and testing by S�bastien Bernard. EBTABLES, ARP tables, and IP/IP6 tables all assume that cpus are numbered linearly. That is not necessarily true. This patch fixes that up by calculating the largest possible cpu number, and allocating enough per-cpu structure space given that. Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
1da177e4 |
|
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!
|