perf maps: Get map before returning in maps__find

Finding a map is done under a lock, returning the map without a
reference count means it can be removed without notice and causing
uses after free. Grab a reference count to the map within the lock
region and return this. Fix up locations that need a map__put
following this.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: James Clark <james.clark@arm.com>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Song Liu <song@kernel.org>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Artem Savkov <asavkov@redhat.com>
Cc: bpf@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240210031746.4057262-3-irogers@google.com

perf env: Avoid recursively taking env->bpf_progs.lock

Add variants of perf_env__insert_bpf_prog_info(), perf_env__insert_btf()
and perf_env__find_btf prefixed with __ to indicate the
env->bpf_progs.lock is assumed held.

Call these variants when the lock is held to avoid recursively taking it
and potentially having a thread deadlock with itself.

Fixes: f8dfeae009effc0b ("perf bpf: Show more BPF program info in print_bpf_prog_info()")
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20231207014655.1252484-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Don't synthesize BPF events when disabled

If BPF sideband events are disabled on the command line, don't
synthesize BPF events too.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Song Liu <song@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Li Dong <lidong@vivo.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20231102175735.2272696-13-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf map: Add accessor for dso

Later changes will add reference count checking for struct map, with
dso being the most frequently accessed variable. Add an accessor so
that the reference count check is only necessary in one place.

Additional changes:
- add a dso variable to avoid repeated map__dso calls.
- in builtin-mem.c dump_raw_samples, code only partially tested for
dso == NULL. Make the possibility of NULL consistent.
- in thread.c thread__memcpy fix use of spaces and use tabs.

Committer notes:

Did missing conversions on these files:

tools/perf/arch/powerpc/util/skip-callchain-idx.c
tools/perf/arch/powerpc/util/sym-handling.c
tools/perf/ui/browsers/hists.c
tools/perf/ui/gtk/annotate.c
tools/perf/util/cs-etm.c
tools/perf/util/thread.c
tools/perf/util/unwind-libunwind-local.c
tools/perf/util/unwind-libunwind.c

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20230320212248.1175731-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Remove pre libbpf 1.0 conditional logic

Tests are no longer applicable as libbpf 1.0 can be assumed.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked/Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked/Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Christy Lee <christylee@fb.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Roberto Sassu <roberto.sassu@huawei.com>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230116010115.490713-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Fix build with libbpf 0.7.0 by adding prototype for bpf_load_program()

The bpf_load_program() prototype appeared in tools/lib/bpf/bpf.h as
deprecated, but nowadays its completely removed, so add it back for
building with the system libbpf when using 'make LIBBPF_DYNAMIC=1'.

This is a stop gap hack till we do like tools/bpf does with bpftool,
i.e. bootstrap the libbpf build and install it in the perf build
directory when not using 'make LIBBPF_DYNAMIC=1'.

That has to be done to all libraries in tools/lib/, so tha we can
remove -Itools/lib/ from the tools/perf CFLAGS.

Noticed when building with LIBBPF_DYNAMIC=1 and libbpf 0.7.0 on RHEL9.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Stop using __weak btf__raw_data() to handle older libbpf versions

By adding a feature test for btf__raw_data() and providing a fallback if
it isn't present in older versions of libbpf.

Committer testing:

$ rpm -q libbpf-devel
libbpf-devel-0.4.0-2.fc35.x86_64
$ make -C tools/perf LIBBPF_DYNAMIC=1 O=/tmp/build/perf install-bin
$ cat /tmp/build/perf/feature/test-libbpf-btf__raw_data.make.output
test-libbpf-btf__raw_data.c: In function ‘main’:
test-libbpf-btf__raw_data.c:6:9: error: implicit declaration of function ‘btf__raw_data’; did you mean ‘btf__get_raw_data’? [-Werror=implicit-function-declaration]
6 | btf__raw_data(NULL /* btf_ro */, NULL /* size */);
| ^~~~~~~~~~~~~
| btf__get_raw_data
cc1: all warnings being treated as errors
$ objdump -dS /tmp/build/perf/perf | grep '<btf__raw_data>:' -A20
00000000005b3050 <btf__raw_data>:
{
5b3050: 55 push %rbp
5b3051: 48 89 e5 mov %rsp,%rbp
5b3054: 48 83 ec 10 sub $0x10,%rsp
5b3058: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax
5b305f: 00 00
5b3061: 48 89 45 f8 mov %rax,-0x8(%rbp)
5b3065: 31 c0 xor %eax,%eax
return btf__get_raw_data(btf_ro, size);
5b3067: 48 8b 45 f8 mov -0x8(%rbp),%rax
5b306b: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax
5b3072: 00 00
5b3074: 75 06 jne 5b307c <btf__raw_data+0x2c>
}
5b3076: c9 leave
return btf__get_raw_data(btf_ro, size);
5b3077: e9 14 99 e5 ff jmp 40c990 <btf__get_raw_data@plt>
5b307c: e8 af a7 e5 ff call 40d830 <__stack_chk_fail@plt>
5b3081: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1)
5b3088: 00 00 00 00
$

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/linux-perf-users/YozLKby7ITEtchC9@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Stop using __weak bpf_object__next_map() to handle older libbpf versions

By adding a feature test for bpf_object__next_map() and providing a fallback if
it isn't present in older versions of libbpf.

Committer testing:

$ rpm -q libbpf-devel
libbpf-devel-0.4.0-2.fc35.x86_64
$ make -C tools/perf LIBBPF_DYNAMIC=1 O=/tmp/build/perf install-bin
$ cat /tmp/build/perf/feature/test-libbpf-bpf_object__next_map.make.output
test-libbpf-bpf_object__next_map.c: In function ‘main’:
test-libbpf-bpf_object__next_map.c:6:9: error: implicit declaration of function ‘bpf_object__next_map’; did you mean ‘bpf_object__next’? [-Werror=implicit-function-declaration]
6 | bpf_object__next_map(NULL /* obj */, NULL /* prev */);
| ^~~~~~~~~~~~~~~~~~~~
| bpf_object__next
cc1: all warnings being treated as errors
$
$ objdump -dS /tmp/build/perf/perf | grep '<bpf_object__next_map>:' -A20
00000000005b2e00 <bpf_object__next_map>:
{
5b2e00: 55 push %rbp
5b2e01: 48 89 e5 mov %rsp,%rbp
5b2e04: 48 83 ec 10 sub $0x10,%rsp
5b2e08: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax
5b2e0f: 00 00
5b2e11: 48 89 45 f8 mov %rax,-0x8(%rbp)
5b2e15: 31 c0 xor %eax,%eax
return bpf_map__next(prev, obj);
5b2e17: 48 8b 45 f8 mov -0x8(%rbp),%rax
5b2e1b: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax
5b2e22: 00 00
5b2e24: 75 0f jne 5b2e35 <bpf_object__next_map+0x35>
}
5b2e26: c9 leave
5b2e27: 49 89 f8 mov %rdi,%r8
5b2e2a: 48 89 f7 mov %rsi,%rdi
return bpf_map__next(prev, obj);
5b2e2d: 4c 89 c6 mov %r8,%rsi
5b2e30: e9 cb b1 e5 ff jmp 40e000 <bpf_map__next@plt>
$

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/linux-perf-users/YozLKby7ITEtchC9@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Stop using __weak bpf_object__next_program() to handle older libbpf versions

By adding a feature test for bpf_object__next_program() and providing a fallback if
it isn't present in older versions of libbpf.

Committer testing:

$ rpm -q libbpf-devel
libbpf-devel-0.4.0-2.fc35.x86_64
$ make -C tools/perf LIBBPF_DYNAMIC=1 O=/tmp/build/perf install-bin
$ cat /tmp/build/perf/feature/test-libbpf-bpf_object__next_program.make.output
test-libbpf-bpf_object__next_program.c: In function ‘main’:
test-libbpf-bpf_object__next_program.c:6:9: error: implicit declaration of function ‘bpf_object__next_program’; did you mean ‘bpf_object__unpin_programs’? [-Werror=implicit-function-declaration]
6 | bpf_object__next_program(NULL /* obj */, NULL /* prev */);
| ^~~~~~~~~~~~~~~~~~~~~~~~
| bpf_object__unpin_programs
cc1: all warnings being treated as errors
$
$ objdump -dS /tmp/build/perf/perf | grep '<bpf_object__next_program>:' -A20
00000000005b2dc0 <bpf_object__next_program>:
{
5b2dc0: 55 push %rbp
5b2dc1: 48 89 e5 mov %rsp,%rbp
5b2dc4: 48 83 ec 10 sub $0x10,%rsp
5b2dc8: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax
5b2dcf: 00 00
5b2dd1: 48 89 45 f8 mov %rax,-0x8(%rbp)
5b2dd5: 31 c0 xor %eax,%eax
return bpf_program__next(prev, obj);
5b2dd7: 48 8b 45 f8 mov -0x8(%rbp),%rax
5b2ddb: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax
5b2de2: 00 00
5b2de4: 75 0f jne 5b2df5 <bpf_object__next_program+0x35>
}
5b2de6: c9 leave
5b2de7: 49 89 f8 mov %rdi,%r8
5b2dea: 48 89 f7 mov %rsi,%rdi
return bpf_program__next(prev, obj);
5b2ded: 4c 89 c6 mov %r8,%rsi
5b2df0: e9 3b b4 e5 ff jmp 40e230 <bpf_program__next@plt>
$

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/linux-perf-users/YozLKby7ITEtchC9@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Stop using __weak bpf_prog_load() to handle older libbpf versions

By adding a feature test for bpf_prog_load() and providing a fallback if
it isn't present in older versions of libbpf.

Committer testing:

$ rpm -q libbpf-devel
libbpf-devel-0.4.0-2.fc35.x86_64
$ make -C tools/perf LIBBPF_DYNAMIC=1 O=/tmp/build/perf install-bin
$ cat /tmp/build/perf/feature/test-libbpf-bpf_prog_load.make.output
test-libbpf-bpf_prog_load.c: In function ‘main’:
test-libbpf-bpf_prog_load.c:6:16: error: implicit declaration of function ‘bpf_prog_load’ [-Werror=implicit-function-declaration]
6 | return bpf_prog_load(0 /* prog_type */, NULL /* prog_name */,
| ^~~~~~~~~~~~~
cc1: all warnings being treated as errors
$

$ objdump -dS /tmp/build/perf/perf | grep '<bpf_prog_load>:' -A20
00000000005b2d70 <bpf_prog_load>:
{
5b2d70: 55 push %rbp
5b2d71: 48 89 ce mov %rcx,%rsi
5b2d74: 4c 89 c8 mov %r9,%rax
5b2d77: 49 89 d2 mov %rdx,%r10
5b2d7a: 4c 89 c2 mov %r8,%rdx
5b2d7d: 48 89 e5 mov %rsp,%rbp
5b2d80: 48 83 ec 18 sub $0x18,%rsp
5b2d84: 64 48 8b 0c 25 28 00 mov %fs:0x28,%rcx
5b2d8b: 00 00
5b2d8d: 48 89 4d f8 mov %rcx,-0x8(%rbp)
5b2d91: 31 c9 xor %ecx,%ecx
return bpf_load_program(prog_type, insns, insn_cnt, license,
5b2d93: 41 8b 49 5c mov 0x5c(%r9),%ecx
5b2d97: 51 push %rcx
5b2d98: 4d 8b 49 60 mov 0x60(%r9),%r9
5b2d9c: 4c 89 d1 mov %r10,%rcx
5b2d9f: 44 8b 40 1c mov 0x1c(%rax),%r8d
5b2da3: e8 f8 aa e5 ff call 40d8a0 <bpf_load_program@plt>
}
$

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/linux-perf-users/YozLKby7ITEtchC9@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Fix check for btf__load_from_kernel_by_id() in libbpf

Avi Kivity reported a problem where the __weak
btf__load_from_kernel_by_id() in tools/perf/util/bpf-event.c was being
used and it called btf__get_from_id() in tools/lib/bpf/btf.c that in
turn called back to btf__load_from_kernel_by_id(), resulting in an
endless loop.

Fix this by adding a feature test to check if
btf__load_from_kernel_by_id() is available when building perf with
LIBBPF_DYNAMIC=1, and if not then provide the fallback to the old
btf__get_from_id(), that doesn't call back to btf__load_from_kernel_by_id()
since at that time it didn't exist at all.

Tested on Fedora 35 where we have libbpf-devel 0.4.0 with LIBBPF_DYNAMIC
where we don't have btf__load_from_kernel_by_id() and thus its feature
test fail, not defining HAVE_LIBBPF_BTF__LOAD_FROM_KERNEL_BY_ID:

$ cat /tmp/build/perf-urgent/feature/test-libbpf-btf__load_from_kernel_by_id.make.output
test-libbpf-btf__load_from_kernel_by_id.c: In function ‘main’:
test-libbpf-btf__load_from_kernel_by_id.c:6:16: error: implicit declaration of function ‘btf__load_from_kernel_by_id’ [-Werror=implicit-function-declaration]
6 | return btf__load_from_kernel_by_id(20151128, NULL);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
$

$ nm /tmp/build/perf-urgent/perf | grep btf__load_from_kernel_by_id
00000000005ba180 T btf__load_from_kernel_by_id
$

$ objdump --disassemble=btf__load_from_kernel_by_id -S /tmp/build/perf-urgent/perf

/tmp/build/perf-urgent/perf: file format elf64-x86-64
<SNIP>
00000000005ba180 <btf__load_from_kernel_by_id>:
#include "record.h"
#include "util/synthetic-events.h"

#ifndef HAVE_LIBBPF_BTF__LOAD_FROM_KERNEL_BY_ID
struct btf *btf__load_from_kernel_by_id(__u32 id)
{
5ba180: 55 push %rbp
5ba181: 48 89 e5 mov %rsp,%rbp
5ba184: 48 83 ec 10 sub $0x10,%rsp
5ba188: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax
5ba18f: 00 00
5ba191: 48 89 45 f8 mov %rax,-0x8(%rbp)
5ba195: 31 c0 xor %eax,%eax
struct btf *btf;
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
int err = btf__get_from_id(id, &btf);
5ba197: 48 8d 75 f0 lea -0x10(%rbp),%rsi
5ba19b: e8 a0 57 e5 ff call 40f940 <btf__get_from_id@plt>
5ba1a0: 89 c2 mov %eax,%edx
#pragma GCC diagnostic pop

return err ? ERR_PTR(err) : btf;
5ba1a2: 48 98 cltq
5ba1a4: 85 d2 test %edx,%edx
5ba1a6: 48 0f 44 45 f0 cmove -0x10(%rbp),%rax
}
<SNIP>

Fixes: 218e7b775d368f38 ("perf bpf: Provide a weak btf__load_from_kernel_by_id() for older libbpf versions")
Reported-by: Avi Kivity <avi@scylladb.com>
Link: https://lore.kernel.org/linux-perf-users/f0add43b-3de5-20c5-22c4-70aff4af959f@scylladb.com
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/linux-perf-users/YobjjFOblY4Xvwo7@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf maps: Use a pointer for kmaps

struct maps is reference counted, using a pointer is more idiomatic.

Committer notes:

Delay:

maps = machine__kernel_maps(&vmlinux);

To after:

machine__init(&vmlinux, "", HOST_KERNEL_ID);

To avoid this on f34:

In file included from /var/home/acme/git/perf/tools/perf/util/build-id.h:10,
from /var/home/acme/git/perf/tools/perf/util/dso.h:13,
from tests/vmlinux-kallsyms.c:8:
In function ‘machine__kernel_maps’,
inlined from ‘test__vmlinux_matches_kallsyms’ at tests/vmlinux-kallsyms.c:122:22:
/var/home/acme/git/perf/tools/perf/util/machine.h:86:23: error: ‘vmlinux.kmaps’ is used uninitialized [-Werror=uninitialized]
86 | return machine->kmaps;
| ~~~~~~~^~~~~~~
tests/vmlinux-kallsyms.c: In function ‘test__vmlinux_matches_kallsyms’:
tests/vmlinux-kallsyms.c:121:34: note: ‘vmlinux’ declared here
121 | struct machine kallsyms, vmlinux;
| ^~~~~~~
cc1: all warnings being treated as errors

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: André Almeida <andrealmeid@collabora.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: http://lore.kernel.org/lkml/20220211103415.2737789-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Stop using deprecated bpf_load_program() API

bpf_load_program() API is deprecated, remove perf's usage of the
deprecated function. Add a __weak function declaration for libbpf
version compatibility.

Signed-off-by: Christy Lee <christylee@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: bpf@vger.kernel.org
Cc: kernel-team@fb.com
Link: https://lore.kernel.org/bpf/20220212073054.1052880-2-andrii@kernel.org
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf: Pull in bpf_program__get_prog_info_linear

To prepare for impending deprecation of libbpf's
bpf_program__get_prog_info_linear, pull in the function and associated
helpers into the perf codebase and migrate existing uses to the perf
copy.

Since libbpf's deprecated definitions will still be visible to perf, it
is necessary to rename perf's definitions.

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20211101224357.2651181-4-davemarchevsky@fb.com

perf tools: Add more weak libbpf functions

We hit the window where perf uses libbpf functions, that did not make it
to the official libbpf release yet and it's breaking perf build with
dynamicly linked libbpf.

Fixing this by providing the new interface as weak functions which calls
the original libbpf functions. Fortunatelly the changes were just
renames.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20211109140707.1689940-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Avoid memory leak from perf_env__insert_btf()

perf_env__insert_btf() doesn't insert if a duplicate BTF id is
encountered and this causes a memory leak. Modify the function to return
a success/error value and then free the memory if insertion didn't
happen.

v2. Adds a return -1 when the insertion error occurs in
perf_env__fetch_btf. This doesn't affect anything as the result is
never checked.

Fixes: 3792cb2ff43b1b19 ("perf bpf: Save BTF in a rbtree in perf_env")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20211112074525.121633-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Add missing free to bpf_event__print_bpf_prog_info()

If btf__new() is called then there needs to be a corresponding btf__free().

Fixes: f8dfeae009effc0b ("perf bpf: Show more BPF program info in print_bpf_prog_info()")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20211106053733.3580931-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Pull in bpf_program__get_prog_info_linear()

To prepare for impending deprecation of libbpf's bpf_program__get_prog_info_linear(),
pull in the function and associated helpers into the perf codebase and migrate
existing uses to the perf copy.

Since libbpf's deprecated definitions will still be visible to perf, it is necessary
to rename perf's definitions.

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20211011082031.4148337-4-davemarchevsky@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Ignore deprecation warning when using libbpf's btf__get_from_id()

Perf code re-implements libbpf's btf__load_from_kernel_by_id() API as
a weak function, presumably to dynamically link against old version of
libbpf shared library. Unfortunately this causes compilation warning
when perf is compiled against libbpf v0.6+.

For now, just ignore deprecation warning, but there might be a better
solution, depending on perf's needs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: kernel-team@fb.com
LPU-Reference: 20210914170004.4185659-1-andrii@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Switch to new btf__raw_data API

Replace the call to btf__get_raw_data with new API btf__raw_data.
The old APIs will be deprecated in libbpf v0.7+. No functionality
change.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211022130623.1548429-3-hengqi.chen@gmail.com

perf bpf: Ignore deprecation warning when using libbpf's btf__get_from_id()

Perf code re-implements libbpf's btf__load_from_kernel_by_id() API as
a weak function, presumably to dynamically link against old version of
libbpf shared library. Unfortunately this causes compilation warning
when perf is compiled against libbpf v0.6+.

For now, just ignore deprecation warning, but there might be a better
solution, depending on perf's needs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: kernel-team@fb.com
LPU-Reference: 20210914170004.4185659-1-andrii@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Provide a weak btf__load_from_kernel_by_id() for older libbpf versions

The btf__get_from_id() function was deprecated in favour of
btf__load_from_kernel_by_id(), but it is still avaiable, so use it to
provide a weak function btf__load_from_kernel_by_id() for older libbpf
when building perf with LIBBPF_DYNAMIC=1, i.e. using the system's libbpf
package.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Fix memory leaks relating to BTF.

BTF needs to be freed with btf__free().

Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210826184833.408563-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools: Replace btf__get_from_id() with btf__load_from_kernel_by_id()

Replace the calls to function btf__get_from_id(), which we plan to
deprecate before the library reaches v1.0, with calls to
btf__load_from_kernel_by_id() in tools/ (bpftool, perf, selftests).
Update the surrounding code accordingly (instead of passing a pointer to
the btf struct, get it as a return value from the function).

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210729162028.29512-6-quentin@isovalent.com

tools: Free BTF objects at various locations

Make sure to call btf__free() (and not simply free(), which does not
free all pointers stored in the struct) on pointers to struct btf
objects retrieved at various locations.

These were found while updating the calls to btf__get_from_id().

Fixes: 999d82cbc044 ("tools/bpf: enhance test_btf file testing to test func info")
Fixes: 254471e57a86 ("tools/bpf: bpftool: add support for func types")
Fixes: 7b612e291a5a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs")
Fixes: d56354dc4909 ("perf tools: Save bpf_prog_info and BTF of new BPF programs")
Fixes: 47c09d6a9f67 ("bpftool: Introduce "prog profile" command")
Fixes: fa853c4b839e ("perf stat: Enable counting events for BPF programs")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210729162028.29512-5-quentin@isovalent.com

perf top: Fix BPF support related crash with perf_event_paranoid=3 + kptr_restrict

After installing the libelf-dev package and compiling perf, if we have
kptr_restrict=2 and perf_event_paranoid=3 'perf top' will crash because
the value of /proc/kallsyms cannot be obtained, which leads to
info->jited_ksyms == NULL. In order to solve this problem, Add a
check before use.

Also plug some leaks on the error path.

Suggested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: jackie liu <liuyun01@kylinos.cn>
Link: http://lore.kernel.org/lkml/20210316012453.1156-1-liuyun01@kylinos.cn
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf evlist: Use the right prefix for 'struct evlist' sideband thread methods

perf_evlist__ is for 'struct perf_evlist' methods, in tools/lib/perf/,
go on completing this split.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Decouple creating the evlist from adding the SB event

Renaming bpf_event__add_sb_event() to evlist__add_sb_event() and
requiring that the evlist be allocated beforehand.

This will allow using the same side band thread and evlist to be used
for multiple purposes in addition to react to PERF_RECORD_BPF_EVENT soon
after they are generated.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-4-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Synthesize bpf_trampoline/dispatcher ksymbol event

Synthesize bpf images (trampolines/dispatchers) on start, as ksymbol
events from /proc/kallsyms. Having this perf can recognize samples from
those images and perf report and top shows them correctly.

The rest of the ksymbol handling is already in place from for the bpf
programs monitoring, so only the initial state was needed.

perf report output:

# Overhead Command Shared Object Symbol

12.37% test_progs [kernel.vmlinux] [k] entry_SYSCALL_64
11.80% test_progs [kernel.vmlinux] [k] syscall_return_via_sysret
9.63% test_progs bpf_prog_bcf7977d3b93787c_prog2 [k] bpf_prog_bcf7977d3b93787c_prog2
6.90% test_progs bpf_trampoline_24456 [k] bpf_trampoline_24456
6.36% test_progs [kernel.vmlinux] [k] memcpy_erms

Committer notes:

Use scnprintf() instead of strncpy() to overcome this on fedora:32,
rawhide and OpenMandriva Cooker:

CC /tmp/build/perf/util/bpf-event.o
In file included from /usr/include/string.h:495,
from /git/linux/tools/lib/bpf/libbpf_common.h:12,
from /git/linux/tools/lib/bpf/bpf.h:31,
from util/bpf-event.c:4:
In function 'strncpy',
inlined from 'process_bpf_image' at util/bpf-event.c:323:2,
inlined from 'kallsyms_process_symbol' at util/bpf-event.c:358:9:
/usr/include/bits/string_fortified.h:106:10: error: '__builtin_strncpy' specified bound 256 equals destination size [-Werror=stringop-truncation]
106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@redhat.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jesper Dangaard Brouer <hawk@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-14-jolsa@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf maps: Merge 'struct maps' with 'struct map_groups'

And pick the shortest name: 'struct maps'.

The split existed because we used to have two groups of maps, one for
functions and one for variables, but that only complicated things,
sometimes we needed to figure out what was at some address and then had
to first try it on the functions group and if that failed, fall back to
the variables one.

That split is long gone, so for quite a while we had only one struct
maps per struct map_groups, simplify things by combining those structs.

First patch is the minimum needed to merge both, follow up patches will
rename 'thread->mg' to 'thread->maps', etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-hom6639ro7020o708trhxh59@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Move event synthesizing routines to separate header

Those are the only routines using the perf_event__handler_t typedef and
are all related, so move to a separate header to reduce the header
dependency tree, lots of places were getting event.h and even stdio.h,
limits.h indirectly, so fix those as well.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-yvx9u1mf7baq6cu1abfhbqgs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf dsos: Move the dsos struct and its methods to separate source files

So that we can reduce the header dependency tree further, in the process
noticed that lots of places were getting even things like build-id
routines and 'struct perf_tool' definition indirectly, so fix all those
too.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-ti0btma9ow5ndrytyoqdk62j@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tool: Rename perf_tool::bpf_event to bpf

No need for that _event suffix, do just like all the other meta event
handlers and suppress that suffix.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lkml.kernel.org/n/tip-03spzxtqafbabbbmnm7y4xfx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Rename perf_event::bpf_event to perf_event::bpf

Just like all the other meta events, that extra _event suffix is just
redundant, ditch it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lkml.kernel.org/n/tip-505qwpaizq1k0t6pk13v1ibd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Rename perf_event::ksymbol_event to perf_event::ksymbol

Just like all the other meta events, that extra _event suffix is just
redundant, ditch it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lkml.kernel.org/n/tip-0q8b2xnfs17q0g523oej75s0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

libperf: Rename the PERF_RECORD_ structs to have a "perf" suffix

Even more, to have a "perf_record_" prefix, so that they match the
PERF_RECORD_ enum they map to.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-qbabmcz2a0pkzt72liyuz3p8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf record: Move record_opts and other record decls out of perf.h

And into a separate util/record.h, to better isolate things and make
sure that those who use record_opts and the other moved declarations
are explicitly including the necessary header.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-31q8mei1qkh74qvkl9nwidfq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf evlist: Rename struct perf_evlist to struct evlist

Rename struct perf_evlist to struct evlist, so we don't have a name
clash when we add struct perf_evlist in libperf.

Committer notes:

Added fixes to build on arm64, from Jiri and from me
(tools/perf/util/cs-etm.c)

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190721112506.12306-6-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Show more BPF program info in print_bpf_prog_info()

This patch enables showing bpf program name, address, and size in the
header.

Before the patch:

perf report --header-only
...
# bpf_prog_info of id 9
# bpf_prog_info of id 10
# bpf_prog_info of id 13

After the patch:

# bpf_prog_info 9: bpf_prog_7be49e3934a125ba addr 0xffffffffa0024947 size 229
# bpf_prog_info 10: bpf_prog_2a142ef67aaad174 addr 0xffffffffa007c94d size 229
# bpf_prog_info 13: bpf_prog_47368425825d7384_task__task_newt addr 0xffffffffa0251137 size 369

Committer notes:

Fix the fallback definition when HAVE_LIBBPF_SUPPORT is not defined,
i.e. add the missing 'static inline' and add the __maybe_unused to the
args. Also add stdio.h since we now use FILE * in bpf-event.h.

Signed-off-by: Song Liu <songliubraving@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190319165454.1298742-3-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Extract logic to create program names from perf_event__synthesize_one_bpf_prog()

Extract logic to create program names to synthesize_bpf_prog_name(), so
that it can be reused in header.c:print_bpf_prog_info().

This commit doesn't change the behavior.

Signed-off-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190319165454.1298742-2-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Save bpf_prog_info and BTF of new BPF programs

To fully annotate BPF programs with source code mapping, 4 different
information are needed:

1) PERF_RECORD_KSYMBOL
2) PERF_RECORD_BPF_EVENT
3) bpf_prog_info
4) btf

This patch handles 3) and 4) for BPF programs loaded after 'perf
record|top'.

For timely process of these information, a dedicated event is added to
the side band evlist.

When PERF_RECORD_BPF_EVENT is received via the side band event, the
polling thread gathers 3) and 4) vis sys_bpf and store them in perf_env.

This information is saved to perf.data at the end of 'perf record'.

Committer testing:

The 'wakeup_watermark' member in 'struct perf_event_attr' is inside a
unnamed union, so can't be used in a struct designated initialization
with older gccs, get it out of that, isolating as 'attr.wakeup_watermark
= 1;' to work with all gcc versions.

We also need to add '--no-bpf-event' to the 'perf record'
perf_event_attr tests in 'perf test', as the way that that test goes is
to intercept the events being setup and looking if they match the fields
described in the control files, since now it finds first the side band
event used to catch the PERF_RECORD_BPF_EVENT, they all fail.

With these issues fixed:

Same scenario as for testing BPF programs loaded before 'perf record' or
'perf top' starts, only start the BPF programs after 'perf record|top',
so that its information get collected by the sideband threads, the rest
works as for the programs loaded before start monitoring.

Add missing 'inline' to the bpf_event__add_sb_event() when
HAVE_LIBBPF_SUPPORT is not defined, fixing the build in systems without
binutils devel files installed.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190312053051.2690567-16-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf annotate: Enable annotation of BPF programs

In symbol__disassemble(), DSO_BINARY_TYPE__BPF_PROG_INFO dso calls into
a new function symbol__disassemble_bpf(), where annotation line
information is filled based on the bpf_prog_info and btf data saved in
given perf_env.

symbol__disassemble_bpf() uses binutils's libopcodes to disassemble bpf
programs.

Committer testing:

After fixing this:

- u64 *addrs = (u64 *)(info_linear->info.jited_ksyms);
+ u64 *addrs = (u64 *)(uintptr_t)(info_linear->info.jited_ksyms);

Detected when crossbuilding to a 32-bit arch.

And making all this dependent on HAVE_LIBBFD_SUPPORT and
HAVE_LIBBPF_SUPPORT:

1) Have a BPF program running, one that has BTF info, etc, I used
the tools/perf/examples/bpf/augmented_raw_syscalls.c put in place
by 'perf trace'.

# grep -B1 augmented_raw ~/.perfconfig
[trace]
add_events = /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c
#
# perf trace -e *mmsg
dnf/6245 sendmmsg(20, 0x7f5485a88030, 2, MSG_NOSIGNAL) = 2
NetworkManager/10055 sendmmsg(22<socket:[1056822]>, 0x7f8126ad1bb0, 2, MSG_NOSIGNAL) = 2

2) Then do a 'perf record' system wide for a while:

# perf record -a
^C[ perf record: Woken up 68 times to write data ]
[ perf record: Captured and wrote 19.427 MB perf.data (366891 samples) ]
#

3) Check that we captured BPF and BTF info in the perf.data file:

# perf report --header-only | grep 'b[pt]f'
# event : name = cycles:ppp, , id = { 294789, 294790, 294791, 294792, 294793, 294794, 294795, 294796 }, size = 112, { sample_period, sample_freq } = 4000, sample_type = IP|TID|TIME|CPU|PERIOD, read_format = ID, disabled = 1, inherit = 1, mmap = 1, comm = 1, freq = 1, task = 1, precise_ip = 3, sample_id_all = 1, exclude_guest = 1, mmap2 = 1, comm_exec = 1, ksymbol = 1, bpf_event = 1
# bpf_prog_info of id 13
# bpf_prog_info of id 14
# bpf_prog_info of id 15
# bpf_prog_info of id 16
# bpf_prog_info of id 17
# bpf_prog_info of id 18
# bpf_prog_info of id 21
# bpf_prog_info of id 22
# bpf_prog_info of id 41
# bpf_prog_info of id 42
# btf info of id 2
#

4) Check which programs got recorded:

# perf report | grep bpf_prog | head
0.16% exe bpf_prog_819967866022f1e1_sys_enter [k] bpf_prog_819967866022f1e1_sys_enter
0.14% exe bpf_prog_c1bd85c092d6e4aa_sys_exit [k] bpf_prog_c1bd85c092d6e4aa_sys_exit
0.08% fuse-overlayfs bpf_prog_819967866022f1e1_sys_enter [k] bpf_prog_819967866022f1e1_sys_enter
0.07% fuse-overlayfs bpf_prog_c1bd85c092d6e4aa_sys_exit [k] bpf_prog_c1bd85c092d6e4aa_sys_exit
0.01% clang-4.0 bpf_prog_c1bd85c092d6e4aa_sys_exit [k] bpf_prog_c1bd85c092d6e4aa_sys_exit
0.01% clang-4.0 bpf_prog_819967866022f1e1_sys_enter [k] bpf_prog_819967866022f1e1_sys_enter
0.00% clang bpf_prog_c1bd85c092d6e4aa_sys_exit [k] bpf_prog_c1bd85c092d6e4aa_sys_exit
0.00% runc bpf_prog_819967866022f1e1_sys_enter [k] bpf_prog_819967866022f1e1_sys_enter
0.00% clang bpf_prog_819967866022f1e1_sys_enter [k] bpf_prog_819967866022f1e1_sys_enter
0.00% sh bpf_prog_c1bd85c092d6e4aa_sys_exit [k] bpf_prog_c1bd85c092d6e4aa_sys_exit
#

This was with the default --sort order for 'perf report', which is:

--sort comm,dso,symbol

If we just look for the symbol, for instance:

# perf report --sort symbol | grep bpf_prog | head
0.26% [k] bpf_prog_819967866022f1e1_sys_enter - -
0.24% [k] bpf_prog_c1bd85c092d6e4aa_sys_exit - -
#

or the DSO:

# perf report --sort dso | grep bpf_prog | head
0.26% bpf_prog_819967866022f1e1_sys_enter
0.24% bpf_prog_c1bd85c092d6e4aa_sys_exit
#

We'll see the two BPF programs that augmented_raw_syscalls.o puts in
place, one attached to the raw_syscalls:sys_enter and another to the
raw_syscalls:sys_exit tracepoints, as expected.

Now we can finally do, from the command line, annotation for one of
those two symbols, with the original BPF program source coude intermixed
with the disassembled JITed code:

# perf annotate --stdio2 bpf_prog_819967866022f1e1_sys_enter

Samples: 950 of event 'cycles:ppp', 4000 Hz, Event count (approx.): 553756947, [percent: local period]
bpf_prog_819967866022f1e1_sys_enter() bpf_prog_819967866022f1e1_sys_enter
Percent int sys_enter(struct syscall_enter_args *args)
53.41 push %rbp

0.63 mov %rsp,%rbp
0.31 sub $0x170,%rsp
1.93 sub $0x28,%rbp
7.02 mov %rbx,0x0(%rbp)
3.20 mov %r13,0x8(%rbp)
1.07 mov %r14,0x10(%rbp)
0.61 mov %r15,0x18(%rbp)
0.11 xor %eax,%eax
1.29 mov %rax,0x20(%rbp)
0.11 mov %rdi,%rbx
return bpf_get_current_pid_tgid();
2.02 → callq *ffffffffda6776d9
2.76 mov %eax,-0x148(%rbp)
mov %rbp,%rsi
int sys_enter(struct syscall_enter_args *args)
add $0xfffffffffffffeb8,%rsi
return bpf_map_lookup_elem(pids, &pid) != NULL;
movabs $0xffff975ac2607800,%rdi

1.26 → callq *ffffffffda6789e9
cmp $0x0,%rax
2.43 → je 0
add $0x38,%rax
0.21 xor %r13d,%r13d
if (pid_filter__has(&pids_filtered, getpid()))
0.81 cmp $0x0,%rax
→ jne 0
mov %rbp,%rdi
probe_read(&augmented_args.args, sizeof(augmented_args.args), args);
2.22 add $0xfffffffffffffeb8,%rdi
0.11 mov $0x40,%esi
0.32 mov %rbx,%rdx
2.74 → callq *ffffffffda658409
syscall = bpf_map_lookup_elem(&syscalls, &augmented_args.args.syscall_nr);
0.22 mov %rbp,%rsi
1.69 add $0xfffffffffffffec0,%rsi
syscall = bpf_map_lookup_elem(&syscalls, &augmented_args.args.syscall_nr);
movabs $0xffff975bfcd36000,%rdi

add $0xd0,%rdi
0.21 mov 0x0(%rsi),%eax
0.93 cmp $0x200,%rax
→ jae 0
0.10 shl $0x3,%rax

0.11 add %rdi,%rax
0.11 → jmp 0
xor %eax,%eax
if (syscall == NULL || !syscall->enabled)
1.07 cmp $0x0,%rax
→ je 0
if (syscall == NULL || !syscall->enabled)
6.57 movzbq 0x0(%rax),%rdi

if (syscall == NULL || !syscall->enabled)
cmp $0x0,%rdi
0.95 → je 0
mov $0x40,%r8d
switch (augmented_args.args.syscall_nr) {
mov -0x140(%rbp),%rdi
switch (augmented_args.args.syscall_nr) {
cmp $0x2,%rdi
→ je 0
cmp $0x101,%rdi
→ je 0
cmp $0x15,%rdi
→ jne 0
case SYS_OPEN: filename_arg = (const void *)args->args[0];
mov 0x10(%rbx),%rdx
→ jmp 0
case SYS_OPENAT: filename_arg = (const void *)args->args[1];
mov 0x18(%rbx),%rdx
if (filename_arg != NULL) {
cmp $0x0,%rdx
→ je 0
xor %edi,%edi
augmented_args.filename.reserved = 0;
mov %edi,-0x104(%rbp)
augmented_args.filename.size = probe_read_str(&augmented_args.filename.value,
mov %rbp,%rdi
add $0xffffffffffffff00,%rdi
augmented_args.filename.size = probe_read_str(&augmented_args.filename.value,
mov $0x100,%esi
→ callq *ffffffffda658499
mov $0x148,%r8d
augmented_args.filename.size = probe_read_str(&augmented_args.filename.value,
mov %eax,-0x108(%rbp)
augmented_args.filename.size = probe_read_str(&augmented_args.filename.value,
mov %rax,%rdi
shl $0x20,%rdi

shr $0x20,%rdi

if (augmented_args.filename.size < sizeof(augmented_args.filename.value)) {
cmp $0xff,%rdi
→ ja 0
len -= sizeof(augmented_args.filename.value) - augmented_args.filename.size;
add $0x48,%rax
len &= sizeof(augmented_args.filename.value) - 1;
and $0xff,%rax
mov %rax,%r8
mov %rbp,%rcx
return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, &augmented_args, len);
add $0xfffffffffffffeb8,%rcx
mov %rbx,%rdi
movabs $0xffff975fbd72d800,%rsi

mov $0xffffffff,%edx
→ callq *ffffffffda658ad9
mov %rax,%r13
}
mov %r13,%rax
0.72 mov 0x0(%rbp),%rbx
mov 0x8(%rbp),%r13
1.16 mov 0x10(%rbp),%r14
0.10 mov 0x18(%rbp),%r15
0.42 add $0x28,%rbp
0.54 leaveq
0.54 ← retq
#

Please see 'man perf-config' to see how to control what should be seen,
via ~/.perfconfig [annotate] section, for instance, one can suppress the
source code and see just the disassembly, etc.

Alternatively, use the TUI bu just using 'perf annotate', press
'/bpf_prog' to see the bpf symbols, press enter and do the interactive
annotation, which allows for dumping to a file after selecting the
the various output tunables, for instance, the above without source code
intermixed, plus showing all the instruction offsets:

# perf annotate bpf_prog_819967866022f1e1_sys_enter

Then press: 's' to hide the source code + 'O' twice to show all
instruction offsets, then 'P' to print to the
bpf_prog_819967866022f1e1_sys_enter.annotation file, which will have:

# cat bpf_prog_819967866022f1e1_sys_enter.annotation
bpf_prog_819967866022f1e1_sys_enter() bpf_prog_819967866022f1e1_sys_enter
Event: cycles:ppp

53.41 0: push %rbp

0.63 1: mov %rsp,%rbp
0.31 4: sub $0x170,%rsp
1.93 b: sub $0x28,%rbp
7.02 f: mov %rbx,0x0(%rbp)
3.20 13: mov %r13,0x8(%rbp)
1.07 17: mov %r14,0x10(%rbp)
0.61 1b: mov %r15,0x18(%rbp)
0.11 1f: xor %eax,%eax
1.29 21: mov %rax,0x20(%rbp)
0.11 25: mov %rdi,%rbx
2.02 28: → callq *ffffffffda6776d9
2.76 2d: mov %eax,-0x148(%rbp)
33: mov %rbp,%rsi
36: add $0xfffffffffffffeb8,%rsi
3d: movabs $0xffff975ac2607800,%rdi

1.26 47: → callq *ffffffffda6789e9
4c: cmp $0x0,%rax
2.43 50: → je 0
52: add $0x38,%rax
0.21 56: xor %r13d,%r13d
0.81 59: cmp $0x0,%rax
5d: → jne 0
63: mov %rbp,%rdi
2.22 66: add $0xfffffffffffffeb8,%rdi
0.11 6d: mov $0x40,%esi
0.32 72: mov %rbx,%rdx
2.74 75: → callq *ffffffffda658409
0.22 7a: mov %rbp,%rsi
1.69 7d: add $0xfffffffffffffec0,%rsi
84: movabs $0xffff975bfcd36000,%rdi

8e: add $0xd0,%rdi
0.21 95: mov 0x0(%rsi),%eax
0.93 98: cmp $0x200,%rax
9f: → jae 0
0.10 a1: shl $0x3,%rax

0.11 a5: add %rdi,%rax
0.11 a8: → jmp 0
aa: xor %eax,%eax
1.07 ac: cmp $0x0,%rax
b0: → je 0
6.57 b6: movzbq 0x0(%rax),%rdi

bb: cmp $0x0,%rdi
0.95 bf: → je 0
c5: mov $0x40,%r8d
cb: mov -0x140(%rbp),%rdi
d2: cmp $0x2,%rdi
d6: → je 0
d8: cmp $0x101,%rdi
df: → je 0
e1: cmp $0x15,%rdi
e5: → jne 0
e7: mov 0x10(%rbx),%rdx
eb: → jmp 0
ed: mov 0x18(%rbx),%rdx
f1: cmp $0x0,%rdx
f5: → je 0
f7: xor %edi,%edi
f9: mov %edi,-0x104(%rbp)
ff: mov %rbp,%rdi
102: add $0xffffffffffffff00,%rdi
109: mov $0x100,%esi
10e: → callq *ffffffffda658499
113: mov $0x148,%r8d
119: mov %eax,-0x108(%rbp)
11f: mov %rax,%rdi
122: shl $0x20,%rdi

126: shr $0x20,%rdi

12a: cmp $0xff,%rdi
131: → ja 0
133: add $0x48,%rax
137: and $0xff,%rax
13d: mov %rax,%r8
140: mov %rbp,%rcx
143: add $0xfffffffffffffeb8,%rcx
14a: mov %rbx,%rdi
14d: movabs $0xffff975fbd72d800,%rsi

157: mov $0xffffffff,%edx
15c: → callq *ffffffffda658ad9
161: mov %rax,%r13
164: mov %r13,%rax
0.72 167: mov 0x0(%rbp),%rbx
16b: mov 0x8(%rbp),%r13
1.16 16f: mov 0x10(%rbp),%r14
0.10 173: mov 0x18(%rbp),%r15
0.42 177: add $0x28,%rbp
0.54 17b: leaveq
0.54 17c: ← retq

Another cool way to test all this is to symple use 'perf top' look for
those symbols, go there and press enter, annotate it live :-)

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190312053051.2690567-13-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Process PERF_BPF_EVENT_PROG_LOAD for annotation

This patch adds processing of PERF_BPF_EVENT_PROG_LOAD, which sets
proper DSO type/id/etc of memory regions mapped to BPF programs to
DSO_BINARY_TYPE__BPF_PROG_INFO.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-14-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Save BTF in a rbtree in perf_env

BTF contains information necessary to annotate BPF programs. This patch
saves BTF for BPF programs loaded in the system.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-9-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Save bpf_prog_info in a rbtree in perf_env

bpf_prog_info contains information necessary to annotate bpf programs.

This patch saves bpf_prog_info for bpf programs loaded in the system.

Some big picture of the next few patches:

To fully annotate BPF programs with source code mapping, 4 different
informations are needed:

1) PERF_RECORD_KSYMBOL
2) PERF_RECORD_BPF_EVENT
3) bpf_prog_info
4) btf

Before this set, 1) and 2) in the list are already saved to perf.data
file. For BPF programs that are already loaded before perf run, 1) and 2)
are synthesized by perf_event__synthesize_bpf_events(). For short living
BPF programs, 1) and 2) are generated by kernel.

This set handles 3) and 4) from the list. Again, it is necessary to handle
existing BPF program and short living program separately.

This patch handles 3) for exising BPF programs while synthesizing 1) and
2) in perf_event__synthesize_bpf_events(). These data are stored in
perf_env. The next patch saves these data from perf_env to perf.data as
headers.

Similarly, the two patches after the next saves 4) of existing BPF
programs to perf_env and perf.data.

Another patch later will handle 3) and 4) for short living BPF programs
by monitoring 1) and 2) in a dedicate thread.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-7-songliubraving@fb.com
[ set env->bpf_progs.infos_cnt to zero in perf_env__purge_bpf() as noted by jolsa ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Make synthesize_bpf_events() receive perf_session pointer instead of perf_tool

This patch changes the arguments of perf_event__synthesize_bpf_events()
to include perf_session* instead of perf_tool*. perf_session will be
used in the next patch.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-6-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Synthesize bpf events with bpf_program__get_prog_info_linear()

With bpf_program__get_prog_info_linear, we can simplify the logic that
synthesizes bpf events.

This patch doesn't change the behavior of the code.

Commiter notes:

Needed this (for all four variables), suggested by Song, to overcome
build failure on debian experimental cross building to MIPS 32-bit:

- u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(info->prog_tags);
+ u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(uintptr_t)(info->prog_tags);

util/bpf-event.c: In function 'perf_event__synthesize_one_bpf_prog':
util/bpf-event.c:143:35: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(info->prog_tags);
^
util/bpf-event.c:144:22: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
__u32 *prog_lens = (__u32 *)(info->jited_func_lens);
^
util/bpf-event.c:145:23: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
__u64 *prog_addrs = (__u64 *)(info->jited_ksyms);
^
util/bpf-event.c:146:22: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
void *func_infos = (void *)(info->func_info);
^
cc1: all warnings being treated as errors

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: kernel-team@fb.com
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190312053051.2690567-5-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf record: Replace option --bpf-event with --no-bpf-event

Currently, monitoring of BPF programs through bpf_event is off by
default for 'perf record'.

To turn it on, the user need to use option "--bpf-event". As BPF gets
wider adoption in different subsystems, this option becomes
inconvenient.

This patch makes bpf_event on by default, and adds option "--no-bpf-event"
to turn it off. Since option --bpf-event is not released yet, it is safe
to remove it.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: kernel-team@fb.com
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190312053051.2690567-2-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf-event: Add missing new line into pr_debug call

Add a missing new line into pr_debug call in perf_event__synthesize_bpf_events(),
so that the error message does not screw the verbose output.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lkml.kernel.org/r/20190220122800.864-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf utils: Silence "Couldn't synthesize bpf events" warning for EPERM

Synthesizing BPF events is only supported for root. Silent warning msg
when non-root user runs perf-record.

Reported-by: David Carrillo-Cisneros <davidca@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Tested-by: David Carrillo-Cisneros <davidca@fb.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190204193140.719740-1-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Fix synthesized PERF_RECORD_KSYMBOL/BPF_EVENT

Added missing machine->id_hdr_size to event->header.size. Also fixed
size of PERF_RECORD_KSYMBOL by removing extra bytes for name.

Committer notes:

We need to malloc that extra machine->id_hdr_size at the start of
perf_event__synthesize_bpf_events() and also need to cast the event to
(void *) otherwise we segfault, fix it.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Suggested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Fixes: 7b612e291a5a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs")
Link: http://lkml.kernel.org/r/20190122210218.358664-1-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Synthesize PERF_RECORD_* for loaded BPF programs

This patch synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for
BPF programs loaded before perf-record. This is achieved by gathering
information about all BPF programs via sys_bpf.

Committer notes:

Fix the build on some older systems such as amazonlinux:1 where it was
breaking with:

util/bpf-event.c: In function 'perf_event__synthesize_one_bpf_prog':
util/bpf-event.c:52:9: error: missing initializer for field 'type' of 'struct bpf_prog_info' [-Werror=missing-field-initializers]
struct bpf_prog_info info = {};
^
In file included from /git/linux/tools/lib/bpf/bpf.h:26:0,
from util/bpf-event.c:3:
/git/linux/tools/include/uapi/linux/bpf.h:2699:8: note: 'type' declared here
__u32 type;
^
cc1: all warnings being treated as errors

Further fix on a centos:6 system:

cc1: warnings being treated as errors
util/bpf-event.c: In function 'perf_event__synthesize_one_bpf_prog':
util/bpf-event.c:50: error: 'func_info_rec_size' may be used uninitialized in this function

The compiler is wrong, but to silence it, initialize that variable to
zero.

One more fix, this time for debian:experimental-x-mips, x-mips64 and
x-mipsel:

util/bpf-event.c: In function 'perf_event__synthesize_one_bpf_prog':
util/bpf-event.c:93:16: error: implicit declaration of function 'calloc' [-Werror=implicit-function-declaration]
func_infos = calloc(sub_prog_cnt, func_info_rec_size);
^~~~~~
util/bpf-event.c:93:16: error: incompatible implicit declaration of built-in function 'calloc' [-Werror]
util/bpf-event.c:93:16: note: include '<stdlib.h>' or provide a declaration of 'calloc'

Add the missing header.

Committer testing:

# perf record --bpf-event sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.021 MB perf.data (7 samples) ]
# perf report -D | grep PERF_RECORD_BPF_EVENT | nl
1 0 0x4b10 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 13
2 0 0x4c60 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 14
3 0 0x4db0 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 15
4 0 0x4f00 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 16
5 0 0x5050 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 17
6 0 0x51a0 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 18
7 0 0x52f0 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 21
8 0 0x5440 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 22
# bpftool prog
13: cgroup_skb tag 7be49e3934a125ba gpl
loaded_at 2019-01-19T09:09:43-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 13,14
14: cgroup_skb tag 2a142ef67aaad174 gpl
loaded_at 2019-01-19T09:09:43-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 13,14
15: cgroup_skb tag 7be49e3934a125ba gpl
loaded_at 2019-01-19T09:09:43-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 15,16
16: cgroup_skb tag 2a142ef67aaad174 gpl
loaded_at 2019-01-19T09:09:43-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 15,16
17: cgroup_skb tag 7be49e3934a125ba gpl
loaded_at 2019-01-19T09:09:44-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 17,18
18: cgroup_skb tag 2a142ef67aaad174 gpl
loaded_at 2019-01-19T09:09:44-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 17,18
21: cgroup_skb tag 7be49e3934a125ba gpl
loaded_at 2019-01-19T09:09:45-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 21,22
22: cgroup_skb tag 2a142ef67aaad174 gpl
loaded_at 2019-01-19T09:09:45-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 21,22
#

# perf report -D | grep -B22 PERF_RECORD_KSYMBOL
. ... raw event: size 312 bytes
. 0000: 11 00 00 00 00 00 38 01 ff 44 06 c0 ff ff ff ff ......8..D......
. 0010: e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67 ........bpf_prog
. 0020: 5f 37 62 65 34 39 65 33 39 33 34 61 31 32 35 62 _7be49e3934a125b
. 0030: 61 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 a...............
<SNIP zeroes>
. 0110: 00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!.......
. 0120: 7b e4 9e 39 34 a1 25 ba 00 00 00 00 00 00 00 00 {..94.%.........
. 0130: 00 00 00 00 00 00 00 00 ........

0 0x49d8 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc00644ff len 229 type 1 flags 0x0 name bpf_prog_7be49e3934a125ba
--
. ... raw event: size 312 bytes
. 0000: 11 00 00 00 00 00 38 01 48 6d 06 c0 ff ff ff ff ......8.Hm......
. 0010: e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67 ........bpf_prog
. 0020: 5f 32 61 31 34 32 65 66 36 37 61 61 61 64 31 37 _2a142ef67aaad17
. 0030: 34 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 4...............
<SNIP zeroes>
. 0110: 00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!.......
. 0120: 2a 14 2e f6 7a aa d1 74 00 00 00 00 00 00 00 00 *...z..t........
. 0130: 00 00 00 00 00 00 00 00 ........

0 0x4b28 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0066d48 len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
--
. ... raw event: size 312 bytes
. 0000: 11 00 00 00 00 00 38 01 04 cf 03 c0 ff ff ff ff ......8.........
. 0010: e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67 ........bpf_prog
. 0020: 5f 37 62 65 34 39 65 33 39 33 34 61 31 32 35 62 _7be49e3934a125b
. 0030: 61 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 a...............
<SNIP zeroes>
. 0110: 00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!.......
. 0120: 7b e4 9e 39 34 a1 25 ba 00 00 00 00 00 00 00 00 {..94.%.........
. 0130: 00 00 00 00 00 00 00 00 ........

0 0x4c78 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc003cf04 len 229 type 1 flags 0x0 name bpf_prog_7be49e3934a125ba
--
. ... raw event: size 312 bytes
. 0000: 11 00 00 00 00 00 38 01 96 28 04 c0 ff ff ff ff ......8..(......
. 0010: e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67 ........bpf_prog
. 0020: 5f 32 61 31 34 32 65 66 36 37 61 61 61 64 31 37 _2a142ef67aaad17
. 0030: 34 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 4...............
<SNIP zeroes>
. 0110: 00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!.......
. 0120: 2a 14 2e f6 7a aa d1 74 00 00 00 00 00 00 00 00 *...z..t........
. 0130: 00 00 00 00 00 00 00 00 ........

0 0x4dc8 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0042896 len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
--
. ... raw event: size 312 bytes
. 0000: 11 00 00 00 00 00 38 01 05 13 17 c0 ff ff ff ff ......8.........
. 0010: e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67 ........bpf_prog
. 0020: 5f 37 62 65 34 39 65 33 39 33 34 61 31 32 35 62 _7be49e3934a125b
. 0030: 61 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 a...............
<SNIP zeroes>
. 0110: 00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!.......
. 0120: 7b e4 9e 39 34 a1 25 ba 00 00 00 00 00 00 00 00 {..94.%.........
. 0130: 00 00 00 00 00 00 00 00 ........

0 0x4f18 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0171305 len 229 type 1 flags 0x0 name bpf_prog_7be49e3934a125ba
--
. ... raw event: size 312 bytes
. 0000: 11 00 00 00 00 00 38 01 0a 8c 23 c0 ff ff ff ff ......8...#.....
. 0010: e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67 ........bpf_prog
. 0020: 5f 32 61 31 34 32 65 66 36 37 61 61 61 64 31 37 _2a142ef67aaad17
. 0030: 34 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 4...............
<SNIP zeroes>
. 0110: 00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!.......
. 0120: 2a 14 2e f6 7a aa d1 74 00 00 00 00 00 00 00 00 *...z..t........
. 0130: 00 00 00 00 00 00 00 00 ........

0 0x5068 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0238c0a len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
--
. ... raw event: size 312 bytes
. 0000: 11 00 00 00 00 00 38 01 2a a5 a4 c0 ff ff ff ff ......8.*.......
. 0010: e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67 ........bpf_prog
. 0020: 5f 37 62 65 34 39 65 33 39 33 34 61 31 32 35 62 _7be49e3934a125b
. 0030: 61 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 a...............
<SNIP zeroes>
. 0110: 00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!.......
. 0120: 7b e4 9e 39 34 a1 25 ba 00 00 00 00 00 00 00 00 {..94.%.........
. 0130: 00 00 00 00 00 00 00 00 ........

0 0x51b8 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0a4a52a len 229 type 1 flags 0x0 name bpf_prog_7be49e3934a125ba
--
. ... raw event: size 312 bytes
. 0000: 11 00 00 00 00 00 38 01 9b c9 a4 c0 ff ff ff ff ......8.........
. 0010: e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67 ........bpf_prog
. 0020: 5f 32 61 31 34 32 65 66 36 37 61 61 61 64 31 37 _2a142ef67aaad17
. 0030: 34 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 4...............
<SNIP zeroes>
. 0110: 00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!.......
. 0120: 2a 14 2e f6 7a aa d1 74 00 00 00 00 00 00 00 00 *...z..t........
. 0130: 00 00 00 00 00 00 00 00 ........

0 0x5308 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0a4c99b len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20190117161521.1341602-8-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Handle PERF_RECORD_BPF_EVENT

This patch adds basic handling of PERF_RECORD_BPF_EVENT. Tracking of
PERF_RECORD_BPF_EVENT is OFF by default. Option --bpf-event is added to
turn it on.

Committer notes:

Add dummy machine__process_bpf_event() variant that returns zero for
systems without HAVE_LIBBPF_SUPPORT, such as Alpine Linux, unbreaking
the build in such systems.

Remove the needless include <machine.h> from bpf->event.h, provide just
forward declarations for the structs and unions in the parameters, to
reduce compilation time and needless rebuilds when machine.h gets
changed.

Committer testing:

When running with:

# perf record --bpf-event

On an older kernel where PERF_RECORD_BPF_EVENT and PERF_RECORD_KSYMBOL
is not present, we fallback to removing those two bits from
perf_event_attr, making the tool to continue to work on older kernels:

perf_event_attr:
size 112
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|PERIOD
read_format ID
disabled 1
inherit 1
mmap 1
comm 1
freq 1
enable_on_exec 1
task 1
precise_ip 3
sample_id_all 1
exclude_guest 1
mmap2 1
comm_exec 1
ksymbol 1
bpf_event 1
------------------------------------------------------------
sys_perf_event_open: pid 5779 cpu 0 group_fd -1 flags 0x8
sys_perf_event_open failed, error -22
switching off bpf_event
------------------------------------------------------------
perf_event_attr:
size 112
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|PERIOD
read_format ID
disabled 1
inherit 1
mmap 1
comm 1
freq 1
enable_on_exec 1
task 1
precise_ip 3
sample_id_all 1
exclude_guest 1
mmap2 1
comm_exec 1
ksymbol 1
------------------------------------------------------------
sys_perf_event_open: pid 5779 cpu 0 group_fd -1 flags 0x8
sys_perf_event_open failed, error -22
switching off ksymbol
------------------------------------------------------------
perf_event_attr:
size 112
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|PERIOD
read_format ID
disabled 1
inherit 1
mmap 1
comm 1
freq 1
enable_on_exec 1
task 1
precise_ip 3
sample_id_all 1
exclude_guest 1
mmap2 1
comm_exec 1
------------------------------------------------------------

And then proceeds to work without those two features.

As passing --bpf-event is an explicit action performed by the user, perhaps we
should emit a warning telling that the kernel has no such feature, but this can
be done on top of this patch.

Now with a kernel that supports these events, start the 'record --bpf-event -a'
and then run 'perf trace sleep 10000' that will use the BPF
augmented_raw_syscalls.o prebuilt (for another kernel version even) and thus
should generate PERF_RECORD_BPF_EVENT events:

[root@quaco ~]# perf record -e dummy -a --bpf-event
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.713 MB perf.data ]

[root@quaco ~]# bpftool prog
13: cgroup_skb tag 7be49e3934a125ba gpl
loaded_at 2019-01-19T09:09:43-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 13,14
14: cgroup_skb tag 2a142ef67aaad174 gpl
loaded_at 2019-01-19T09:09:43-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 13,14
15: cgroup_skb tag 7be49e3934a125ba gpl
loaded_at 2019-01-19T09:09:43-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 15,16
16: cgroup_skb tag 2a142ef67aaad174 gpl
loaded_at 2019-01-19T09:09:43-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 15,16
17: cgroup_skb tag 7be49e3934a125ba gpl
loaded_at 2019-01-19T09:09:44-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 17,18
18: cgroup_skb tag 2a142ef67aaad174 gpl
loaded_at 2019-01-19T09:09:44-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 17,18
21: cgroup_skb tag 7be49e3934a125ba gpl
loaded_at 2019-01-19T09:09:45-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 21,22
22: cgroup_skb tag 2a142ef67aaad174 gpl
loaded_at 2019-01-19T09:09:45-0300 uid 0
xlated 296B jited 229B memlock 4096B map_ids 21,22
31: tracepoint name sys_enter tag 12504ba9402f952f gpl
loaded_at 2019-01-19T09:19:56-0300 uid 0
xlated 512B jited 374B memlock 4096B map_ids 30,29,28
32: tracepoint name sys_exit tag c1bd85c092d6e4aa gpl
loaded_at 2019-01-19T09:19:56-0300 uid 0
xlated 256B jited 191B memlock 4096B map_ids 30,29
# perf report -D | grep PERF_RECORD_BPF_EVENT | nl
1 0 55834574849 0x4fc8 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 13
2 0 60129542145 0x5118 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 14
3 0 64424509441 0x5268 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 15
4 0 68719476737 0x53b8 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 16
5 0 73014444033 0x5508 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 17
6 0 77309411329 0x5658 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 18
7 0 90194313217 0x57a8 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 21
8 0 94489280513 0x58f8 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 22
9 7 620922484360 0xb6390 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 29
10 7 620922486018 0xb6410 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 2, flags 0, id 29
11 7 620922579199 0xb6490 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 30
12 7 620922580240 0xb6510 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 2, flags 0, id 30
13 7 620922765207 0xb6598 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 31
14 7 620922874543 0xb6620 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 32
#

There, the 31 and 32 tracepoint BPF programs put in place by 'perf trace'.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20190117161521.1341602-7-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>