linux-stable.git/tools/perf/tests/switch-tracking.c, branch linux-5.4.y

perf tests switch-tracking: Fix timestamp comparison

2025-06-27T10:02:48+00:00

[ Upstream commit 628e124404b3db5e10e17228e680a2999018ab33 ]

The test might fail on the Arm64 platform with the error:

  # perf test -vvv "Track with sched_switch"
  Missing sched_switch events
  #

The issue is caused by incorrect handling of timestamp comparisons. The
comparison result, a signed 64-bit value, was being directly cast to an
int, leading to incorrect sorting for sched events.

The case does not fail everytime, usually I can trigger the failure
after run 20 ~ 30 times:

  # while true; do perf test "Track with sched_switch"; done
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : FAILED!
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : FAILED!
  106: Track with sched_switch                                         : Ok
  106: Track with sched_switch                                         : Ok

I used cross compiler to build Perf tool on my host machine and tested on
Debian / Juno board.  Generally, I think this issue is not very specific
to GCC versions.  As both internal CI and my local env can reproduce the
issue.

My Host Build compiler:

  # aarch64-linux-gnu-gcc --version
  aarch64-linux-gnu-gcc (Ubuntu 13.3.0-6ubuntu2~24.04) 13.3.0

Juno Board:

  # lsb_release -a
  No LSB modules are available.
  Distributor ID: Debian
  Description:    Debian GNU/Linux 12 (bookworm)
  Release:        12
  Codename:       bookworm

Fix this by explicitly returning 0, 1, or -1 based on whether the result
is zero, positive, or negative.

Fixes: d44bc558297222d9 ("perf tests: Add a test for tracking with sched_switch")
Reviewed-by: Ian Rogers 
Signed-off-by: Leo Yan 
Cc: Adrian Hunter 
Cc: James Clark 
Cc: Kan Liang 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/r/20250331172759.115604-1-leo.yan@arm.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libperf: Add perf_evlist__first()/last() functions

2019-09-25T12:51:48+00:00

Add perf_evlist__first()/last() functions to libperf, as internal
functions and rename perf's origins to evlist__first/last.

Signed-off-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20190913132355.21634-29-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

libperf: Move 'nr_mmaps' from 'struct evlist' to 'struct perf_evlist'

2019-09-25T12:51:47+00:00

Moving 'nr_mmaps' from 'struct evlist' to 'struct perf_evlist', it will
be used in following patches.

Signed-off-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20190913132355.21634-21-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

libperf: Move 'system_wide' from 'struct evsel' to 'struct perf_evsel'

2019-09-25T12:51:46+00:00

Move the 'system_wide 'member from perf's evsel to libperf's perf_evsel.

Committer notes:

Added stdbool.h as we now use bool here.

Signed-off-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20190913132355.21634-20-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Adopt backwards ring buffer state enum

2019-09-25T12:51:45+00:00

As this isn't used at all in mmap.h but in evlist.h, so to cut down the
header dependency tree, move it to where it is used.

Also add mmap.h to the places using it but previously getting it
indirectly via evlist.h.

Add missing pthread.h to evlist.h, as it has a pthread_t struct member
and was getting the header via mmap.h.

Noticed while processing a Jiri's libperf batch touching mmap.h, where
almost everything gets rebuilt because evlist.h is so popular, so cut
down't this rebuild the world party.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Song Liu 
Link: https://lkml.kernel.org/n/tip-he0uljeftl0xfveh3d6vtode@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Rename perf_evlistmmap() to evlistmmap()

2019-09-25T12:51:44+00:00

Rename perf_evlist__mmap() to evlist__mmap(), so we don't have a name
clash when we add perf_evlist__mmap() in libperf.

Signed-off-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20190913132355.21634-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Rename 'struct perf_mmap' to 'struct mmap'

2019-09-25T12:51:44+00:00

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

Signed-off-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20190913132355.21634-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf env: Remove needless cpumap.h header

2019-09-20T12:19:21+00:00

Only a 'struct perf_cmp_map' forward allocation is necessary, fix the
places that need the header but were getting it indirectly, by luck,
from env.h.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lkml.kernel.org/n/tip-3sj3n534zghxhk7ygzeaqlx9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf auxtrace: Uninline functions that touch perf_session

2019-09-01T01:24:10+00:00

So that we don't carry the session.h include directive in auxtrace.h,
which in turn opens a can of worms of files that were getting all sorts
of things via that include, fix them all.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lkml.kernel.org/n/tip-d2d83aovpgri2z75wlitquni@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove debug.h from header files not needing it

2019-08-29T20:38:32+00:00

And fix the fallout, adding it to places that must have it since they
use its definitions.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lkml.kernel.org/n/tip-1s3jel4i26chq2g0lydoz7i3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo