linux-toradex.git/tools/perf/builtin-record.c, branch v6.3

perf record: Fix segfault with --overwrite and --max-size

2023-02-15T12:58:55+00:00

When --overwrite and --max-size options of perf record are used
together, a segmentation fault occurs. The following is an example:

  # perf record -e sched:sched* --overwrite --max-size 1K -a -- sleep 1
  [ perf record: Woken up 1 times to write data ]
  perf: Segmentation fault
  Obtained 12 stack frames.
  ./perf/perf(+0x197673) [0x55f99710b673]
  /lib/x86_64-linux-gnu/libc.so.6(+0x3ef0f) [0x7fa45f3cff0f]
  ./perf/perf(+0x8eb40) [0x55f997002b40]
  ./perf/perf(+0x1f6882) [0x55f99716a882]
  ./perf/perf(+0x794c2) [0x55f996fed4c2]
  ./perf/perf(+0x7b7c7) [0x55f996fef7c7]
  ./perf/perf(+0x9074b) [0x55f99700474b]
  ./perf/perf(+0x12e23c) [0x55f9970a223c]
  ./perf/perf(+0x12e54a) [0x55f9970a254a]
  ./perf/perf(+0x7db60) [0x55f996ff1b60]
  /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe6) [0x7fa45f3b2c86]
  ./perf/perf(+0x7dfe9) [0x55f996ff1fe9]
  Segmentation fault (core dumped)

backtrace of the core file is as follows:

  (gdb) bt
  #0  record__bytes_written (rec=0x55f99755a200 ) at builtin-record.c:234
  #1  record__output_max_size_exceeded (rec=0x55f99755a200 ) at builtin-record.c:242
  #2  record__write (map=0x0, size=12816, bf=0x55f9978da2e0, rec=0x55f99755a200 ) at builtin-record.c:263
  #3  process_synthesized_event (tool=tool@entry=0x55f99755a200 , event=event@entry=0x55f9978da2e0, sample=sample@entry=0x0, machine=machine@entry=0x55f997893658) at builtin-record.c:618
  #4  0x000055f99716a883 in __perf_event__synthesize_id_index (tool=tool@entry=0x55f99755a200 , process=process@entry=0x55f997002aa0 , evlist=0x55f9978928b0, machine=machine@entry=0x55f997893658,
      from=from@entry=0) at util/synthetic-events.c:1895
  #5  0x000055f99716a91f in perf_event__synthesize_id_index (tool=tool@entry=0x55f99755a200 , process=process@entry=0x55f997002aa0 , evlist=, machine=machine@entry=0x55f997893658)
      at util/synthetic-events.c:1905
  #6  0x000055f996fed4c3 in record__synthesize (tail=tail@entry=true, rec=0x55f99755a200 ) at builtin-record.c:1997
  #7  0x000055f996fef7c8 in __cmd_record (argc=argc@entry=2, argv=argv@entry=0x7ffc67551260, rec=0x55f99755a200 ) at builtin-record.c:2802
  #8  0x000055f99700474c in cmd_record (argc=, argv=0x7ffc67551260) at builtin-record.c:4258
  #9  0x000055f9970a223d in run_builtin (p=0x55f997564d88 , argc=10, argv=0x7ffc67551260) at perf.c:330
  #10 0x000055f9970a254b in handle_internal_command (argc=10, argv=0x7ffc67551260) at perf.c:384
  #11 0x000055f996ff1b61 in run_argv (argcp=, argv=) at perf.c:428
  #12 main (argc=, argv=0x7ffc67551260) at perf.c:562

The reason is that record__bytes_written accesses the freed memory rec->thread_data,
The process is as follows:
  __cmd_record
    -> record__free_thread_data
      -> zfree(&rec->thread_data)         // free rec->thread_data
    -> record__synthesize
      -> perf_event__synthesize_id_index
        -> process_synthesized_event
          -> record__write
            -> record__bytes_written      // access rec->thread_data

We add a member variable "thread_bytes_written" in the struct "record"
to save the data size written by the threads.

Fixes: 6d57581659f72299 ("perf record: Add support for limit perf output file size")
Signed-off-by: Yang Jihong 
Acked-by: Namhyung Kim 
Cc: Alexander Shishkin 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Jiwei Sun 
Cc: Mark Rutland 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/CAM9d7ci_TRrqBQVQNW8=GwakUr7SsZpYxaaty-S4bxF8zJWyqw@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix usage of the verbose variable

2022-12-20T18:16:33+00:00

The data type of the verbose variable is integer and can be negative,
replace improperly used cases in a unified manner:
 1. if (verbose)        => if (verbose > 0)
 2. if (!verbose)       => if (verbose <= 0)
 3. if (XX && verbose)  => if (XX && verbose > 0)
 4. if (XX && !verbose) => if (XX && verbose <= 0)

Reviewed-by: Adrian Hunter 
Signed-off-by: Yang Jihong 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Carsten Haitzler 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Martin KaFai Lau 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Link: https://lore.kernel.org/r/20221220035702.188413-3-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Remove group option.

2022-12-14T18:28:18+00:00

The group option predates grouping events using curly braces added in
commit 89efb029502d7f2d ("perf tools: Add support to parse event group
syntax").

The --group option was retained for legacy support (in August
2012) but keeping it adds complexity.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexey Bayduraev 
Cc: Andi Kleen 
Cc: Anshuman Khandual 
Cc: Athira Jajeev 
Cc: Eelco Chaudron 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Kim Phillips 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Sandipan Das 
Cc: Sean Christopherson 
Cc: Shaomin Deng 
Cc: Stephane Eranian 
Cc: Timothy Hayes 
Cc: Xing Zhengjun 
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221213232651.1269909-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Use libtraceevent from the system

2022-12-14T14:16:12+00:00

Remove the LIBTRACEEVENT_DYNAMIC and LIBTRACEFS_DYNAMIC make command
line variables.

If libtraceevent isn't installed or NO_LIBTRACEEVENT=1 is passed to the
build, don't compile in libtraceevent and libtracefs support.

This also disables CONFIG_TRACE that controls "perf trace".

CONFIG_LIBTRACEEVENT is used to control enablement in Build/Makefiles,
HAVE_LIBTRACEEVENT is used in C code.

Without HAVE_LIBTRACEEVENT tracepoints are disabled and as such the
commands kmem, kwork, lock, sched and timechart are removed.  The
majority of commands continue to work including "perf test".

Committer notes:

Fixed up a tools/perf/util/Build reject and added:

  #include 

to tools/perf/util/scripting-engines/trace-event-perl.c.

Committer testing:

  $ rpm -qi libtraceevent-devel
  Name        : libtraceevent-devel
  Version     : 1.5.3
  Release     : 2.fc36
  Architecture: x86_64
  Install Date: Mon 25 Jul 2022 03:20:19 PM -03
  Group       : Unspecified
  Size        : 27728
  License     : LGPLv2+ and GPLv2+
  Signature   : RSA/SHA256, Fri 15 Apr 2022 02:11:58 PM -03, Key ID 999f7cbf38ab71f4
  Source RPM  : libtraceevent-1.5.3-2.fc36.src.rpm
  Build Date  : Fri 15 Apr 2022 10:57:01 AM -03
  Build Host  : buildvm-x86-05.iad2.fedoraproject.org
  Packager    : Fedora Project
  Vendor      : Fedora Project
  URL         : https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/
  Bug URL     : https://bugz.fedoraproject.org/libtraceevent
  Summary     : Development headers of libtraceevent
  Description :
  Development headers of libtraceevent-libs
  $

Default build:

  $ ldd ~/bin/perf | grep tracee
  	libtraceevent.so.1 => /lib64/libtraceevent.so.1 (0x00007f1dcaf8f000)
  $

  # perf trace -e sched:* --max-events 10
       0.000 migration/0/17 sched:sched_migrate_task(comm: "", pid: 1603763 (perf), prio: 120, dest_cpu: 1)
       0.005 migration/0/17 sched:sched_wake_idle_without_ipi(cpu: 1)
       0.011 migration/0/17 sched:sched_switch(prev_comm: "", prev_pid: 17 (migration/0), prev_state: 1, next_comm: "", next_prio: 120)
       1.173 :0/0 sched:sched_wakeup(comm: "", pid: 3138 (gnome-terminal-), prio: 120)
       1.180 :0/0 sched:sched_switch(prev_comm: "", prev_prio: 120, next_comm: "", next_pid: 3138 (gnome-terminal-), next_prio: 120)
       0.156 migration/1/21 sched:sched_migrate_task(comm: "", pid: 1603763 (perf), prio: 120, orig_cpu: 1, dest_cpu: 2)
       0.160 migration/1/21 sched:sched_wake_idle_without_ipi(cpu: 2)
       0.166 migration/1/21 sched:sched_switch(prev_comm: "", prev_pid: 21 (migration/1), prev_state: 1, next_comm: "", next_prio: 120)
       1.183 :0/0 sched:sched_wakeup(comm: "", pid: 1602985 (kworker/u16:0-f), prio: 120, target_cpu: 1)
       1.186 :0/0 sched:sched_switch(prev_comm: "", prev_prio: 120, next_comm: "", next_pid: 1602985 (kworker/u16:0-f), next_prio: 120)
  #

Had to tweak tools/perf/util/setup.py to make sure the python binding
shared object links with libtraceevent if -DHAVE_LIBTRACEEVENT is
present in CFLAGS.

Building with NO_LIBTRACEEVENT=1 uncovered some more build failures:

- Make building of data-convert-bt.c to CONFIG_LIBTRACEEVENT=y

- perf-$(CONFIG_LIBTRACEEVENT) += scripts/

- bpf_kwork.o needs also to be dependent on CONFIG_LIBTRACEEVENT=y

- The python binding needed some fixups and util/trace-event.c can't be
  built and linked with the python binding shared object, so remove it
  in tools/perf/util/setup.py and exclude it from the list of
  dependencies in the python/perf.so Makefile.perf target.

Building without libtraceevent-devel installed uncovered more build
failures:

- The python binding tools/perf/util/python.c was assuming that
  traceevent/parse-events.h was always available, which was the case
  when we defaulted to using the in-kernel tools/lib/traceevent/ files,
  now we need to enclose it under ifdef HAVE_LIBTRACEEVENT, just like
  the other parts of it that deal with tracepoints.

- We have to ifdef the rules in the Build files with
  CONFIG_LIBTRACEEVENT=y to build builtin-trace.c and
  tools/perf/trace/beauty/ as we only ifdef setting CONFIG_TRACE=y when
  setting NO_LIBTRACEEVENT=1 in the make command line, not when we don't
  detect libtraceevent-devel installed in the system. Simplification here
  to avoid these two ways of disabling builtin-trace.c and not having
  CONFIG_TRACE=y when libtraceevent-devel isn't installed is the clean
  way.

From Athira:


tools/perf/arch/powerpc/util/Build
-perf-y += kvm-stat.o
+perf-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o


Then, ditto for arm64 and s390, detected by container cross build tests.

- s/390 uses test__checkevent_tracepoint() that is now only available if
  HAVE_LIBTRACEEVENT is defined, enclose the callsite with ifder HAVE_LIBTRACEEVENT.

Also from Athira:


With this change, I could successfully compile in these environment:
- Without libtraceevent-devel installed
- With libtraceevent-devel installed
- With “make NO_LIBTRACEEVENT=1”


Then, finally rename CONFIG_TRACEEVENT to CONFIG_LIBTRACEEVENT for
consistency with other libraries detected in tools/perf/.

Signed-off-by: Ian Rogers 
Tested-by: Arnaldo Carvalho de Melo 
Tested-by: Athira Rajeev 
Cc: Alexander Shishkin 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nick Desaulniers 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20221205225940.3079667-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Use dedicated non-atomic clear/set bit helpers

2022-12-05T12:29:06+00:00

Use the dedicated non-atomic helpers for {clear,set}_bit() and their
test variants, i.e. the double-underscore versions.  Depsite being
defined in atomic.h, and despite the kernel versions being atomic in the
kernel, tools' {clear,set}_bit() helpers aren't actually atomic.  Move
to the double-underscore versions so that the versions that are expected
to be atomic (for kernel developers) can be made atomic without
affecting users that don't want atomic operations.

No functional change intended.

Signed-off-by: Sean Christopherson 
Acked-by: Namhyung Kim 
Cc: Alexander Shishkin 
Cc: Andy Shevchenko 
Cc: James Morse 
Cc: Jiri Olsa 
Cc: Marc Zyngier 
Cc: Mark Rutland 
Cc: Oliver Upton 
Cc: Paolo Bonzini 
Cc: Peter Zijlstra 
Cc: Rasmus Villemoes 
Cc: Sean Christopherson 
Cc: Suzuki Poulouse 
Cc: Yury Norov 
Cc: alexandru elisei 
Cc: kvm@vger.kernel.org
Cc: kvmarm@lists.cs.columbia.edu
Cc: kvmarm@lists.linux.dev
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20221119013450.2643007-6-seanjc@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf record: Use sig_atomic_t for signal handlers

2022-11-03T12:34:40+00:00

This removes undefined behavior as described in:

  https://wiki.sei.cmu.edu/confluence/display/c/SIG31-C.+Do+not+access+shared+objects+in+signal+handlers

Suggested-by: Leo Yan 
Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexey Bayduraev 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20221024181913.630986-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Make quiet mode consistent between tools

2022-10-27T19:37:26+00:00

Use the global quiet variable everywhere so that all tools hide warnings
in quiet mode and update the documentation to reflect this.

'perf probe' claimed that errors are not printed in quiet mode but I
don't see this so remove it from the docs.

Signed-off-by: James Clark 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20221018094137.783081-3-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf record: Fix event fd races

2022-10-25T20:40:48+00:00

The write call may set errno which is problematic if occurring in a
function also setting errno. Save and restore errno around the write
call.

done_fd may be used after close, clear it as part of the close and check
its validity in the signal handler.

Suggested-by: 
Reviewed-by: Leo Yan 
Signed-off-by: Ian Rogers 
Cc: Alexander Shishkin 
Cc: Anand K Mistry 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20221024011024.462518-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add debug messages and comments for testing

2022-10-04T11:55:23+00:00

Add debug messages to enable scripts to track aspects of 'perf record'
behaviour. The messages will be consumed after 'perf record' has run,
with the exception of "perf record has started" which is consequently
flushed.

Put comments so developers know which messages are also being used by test
scripts.

Signed-off-by: Adrian Hunter 
Acked-by: Namhyung Kim 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Link: https://lore.kernel.org/r/20220912083412.7058-11-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf record: Fix a segfault in record__read_lost_samples()

2022-10-04T11:55:22+00:00

When it fails to open events record__open() returns without setting the
session->evlist.  Then it gets a segfault in the function trying to read
lost sample counts.  You can easily reproduce it as a normal user like:

  $ perf record -p 1 true
  ...
  perf: Segmentation fault
  ...

Skip the function if it has no evlist.  And add more protection for evsels
which are not properly initialized.

Fixes: a49aa8a54e861af1 ("perf record: Read and inject LOST_SAMPLES events")
Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Acked-by: Leo Yan 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20220909235024.278281-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo