linux.git/tools/tracing, branch v6.18.21

rtla: Fix NULL pointer dereference in actions_parse

2026-03-04T12:20:13+00:00

[ Upstream commit a0890f9dbd24b302d327fe7dad9b9c5be0e278aa ]

The actions_parse() function uses strtok() to tokenize the trigger
string, but does not check if the returned token is NULL before
passing it to strcmp(). If the trigger parameter is an empty string
or contains only delimiter characters, strtok() returns NULL, causing
strcmp() to dereference a NULL pointer and crash the program.

This issue can be triggered by malformed user input or edge cases in
trigger string parsing. Add a NULL check immediately after the strtok()
call to validate that a token was successfully extracted before using
it. If no token is found, the function now returns -1 to indicate a
parsing error.

Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260106133655.249887-13-wander@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

rtla/timerlat_bpf: Stop tracing on user latency

2026-01-02T11:57:29+00:00

commit e4240db9336c25826a2d6634adcca86d5ee01bde upstream.

rtla-timerlat allows a *thread* latency threshold to be set via the
-T/--thread option. However, the timerlat tracer calls this *total*
latency (stop_tracing_total_us), and stops tracing also when the
return-to-user latency is over the threshold.

Change the behavior of the timerlat BPF program to reflect what the
timerlat tracer is doing, to avoid discrepancy between stopping
collecting data in the BPF program and stopping tracing in the timerlat
tracer.

Cc: stable@vger.kernel.org
Fixes: e34293ddcebd ("rtla/timerlat: Add BPF skeleton to collect samples")
Reviewed-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20251006143100.137255-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Greg Kroah-Hartman

rtla: Fix -a overriding -t argument

2025-12-18T13:03:10+00:00

[ Upstream commit ddb6e42494e5c48c17e64f29b7674b9add486a19 ]

When running rtla as

    `rtla   -t custom_file.txt -a 100`

-a options override trace output filename specified by -t option.
Running the command above will create _trace.txt file
instead of custom_file.txt. Fix this by making sure that -a option does
not override trace output filename even if it's passed after trace
output filename is specified.

Fixes: 173a3b014827 ("rtla/timerlat: Add the automatic trace option")
Signed-off-by: Ivan Pravdin 
Reviewed-by: Tomas Glozar 
Link: https://lore.kernel.org/r/b6ae60424050b2c1c8709e18759adead6012b971.1762186418.git.ipravdin.official@gmail.com
[ use capital letter in subject, as required by tracing subsystem ]
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

rtla/tests: Fix osnoise test calling timerlat

2025-12-18T13:03:10+00:00

[ Upstream commit 34c170ae5c3036ef879567a37409a2859e327342 ]

osnoise test "top stop at failed action" is calling timerlat instead of
osnoise by mistake.

Fix it so that it calls the correct RTLA subcommand.

Fixes: 05b7e10687c6 ("tools/rtla: Add remaining support for osnoise actions")
Reviewed-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20251007095341.186923-3-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

rtla/tests: Extend action tests to 5s

2025-12-18T13:03:10+00:00

[ Upstream commit d649e9f04cb0224817dac8190461ef1674e32b37 ]

In non-BPF mode, it takes up to 1 second for RTLA to notice that tracing
has been stopped. That means that action tests cannot have a 1 second
duration, as the SIGALRM will be racing with the threshold overflow.

Previously, non-BPF mode actions were buggy and always executed
the action, even when stopping on duration or SIGINT, preventing
this issue from manifesting. Now that this has been fixed, the tests
have become flaky, and this has to be adjusted.

Fixes: 4e26f84abfbb ("rtla/tests: Add tests for actions")
Fixes: 05b7e10687c6 ("tools/rtla: Add remaining support for osnoise actions")
Reviewed-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20251007095341.186923-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

tools/rtla: Fix --on-threshold always triggering

2025-12-18T13:03:07+00:00

[ Upstream commit 417bd0d502f90a2e785e7299dae4f248b5ac0292 ]

Commit 8d933d5c89e8 ("rtla/timerlat: Add continue action") moved the
code performing on-threshold actions (enabled through --on-threshold
option) to inside the RTLA main loop.

The condition in the loop does not check whether the threshold was
actually exceeded or if stop tracing was requested by the user through
SIGINT or duration. This leads to a bug where on-threshold actions are
always performed, even when the threshold was not hit.

(BPF mode is not affected, since it uses a different condition in the
while loop.)

Add a condition that checks for !stop_tracing before executing the
actions. Also, fix incorrect brackets in hist_main_loop to match the
semantics of top_main_loop.

Fixes: 8d933d5c89e8 ("rtla/timerlat: Add continue action")
Fixes: 2f3172f9dd58 ("tools/rtla: Consolidate code between osnoise/timerlat and hist/top")
Reviewed-by: Crystal Wood 
Reviewed-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20251007095341.186923-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

tools/rtla: Fix unassigned nr_cpus

2025-12-18T13:03:07+00:00

[ Upstream commit b4275b23010df719ec6508ddbc84951dcd24adce ]

In recently introduced timerlat_free(),
the variable 'nr_cpus' is not assigned.

Assign it with sysconf(_SC_NPROCESSORS_CONF) as done elsewhere.
Remove the culprit: -Wno-maybe-uninitialized. The rest of the
code is clean.

Signed-off-by: Costa Shulyupin 
Reviewed-by: Tomas Glozar 
Fixes: 2f3172f9dd58 ("tools/rtla: Consolidate code between osnoise/timerlat and hist/top")
Link: https://lore.kernel.org/r/20251002170846.437888-1-costa.shul@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

tracing/tools: Fix incorrcet short option in usage text for --threads

2025-11-07T12:59:37+00:00

The help message incorrectly listed '-t' as the short option for
--threads, but the actual getopt_long configuration uses '-e'.
This mismatch can confuse users and lead to incorrect command-line
usage. This patch updates the usage string to correctly show:
	"-e, --threads NRTHR"
to match the implementation.

Note: checkpatch.pl reports a false-positive spelling warning on
'Run', which is intentional.

Link: https://patch.msgid.link/20251106031040.1869-1-zhangchujun@cmss.chinamobile.com
Signed-off-by: Zhang Chujun 
Signed-off-by: Steven Rostedt (Google)

Merge tag 'trace-tools-v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2025-10-05T16:38:26+00:00

Pull tracing tools updates from Steven Rostedt

 - This is mostly just consolidating code between osnoise/timerlat and
   top/hist for easier maintenance and less future divergence

* tag 'trace-tools-v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tools/rtla: Add remaining support for osnoise actions
  tools/rtla: Add test engine support for unexpected output
  tools/rtla: Fix -A option name in test comment
  tools/rtla: Consolidate code between osnoise/timerlat and hist/top
  tools/rtla: Create common_apply_config()
  tools/rtla: Move top/hist params into common struct
  tools/rtla: Consolidate common parameters into shared structure

rtla/actions: Fix condition for buffer reallocation

2025-09-27T10:01:20+00:00

The condition to check if the actions buffer needs to be resized was
incorrect. The check `self->size >= self->len` would evaluate to
true on almost every call to `actions_new()`, causing the buffer to
be reallocated unnecessarily each time an action was added.

Fix the condition to `self->len >= self.size`, ensuring
that the buffer is only resized when it is actually full.

Cc: John Kacur 
Cc: Luis Goncalves 
Cc: Arnaldo Carvalho de Melo 
Cc: Chang Yin 
Cc: Costa Shulyupin 
Cc: Crystal Wood 
Cc: Gabriele Monaco 
Link: https://lore.kernel.org/20250915181101.52513-1-wander@redhat.com
Fixes: 6ea082b171e00 ("rtla/timerlat: Add action on threshold feature")
Signed-off-by: Wander Lairson Costa 
Reviewed-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google)