linux-stable.git/tools/tracing, branch v6.18.41

rtla/actions: Restore continue flag in actions_perform()

2026-07-24T14:15:54+00:00

[ Upstream commit dd520daffbc901f10d49a51a58313547d417b506 ]

Currently, actions_perform() only ever sets the continue flag (when
performing the continue action), but never resets it. That leads to
RTLA continuing tracing even if the continue action was not performed in
the current iteration.

For example, the following command:

$ rtla timerlat hist -T 100 --on-threshold shell,command='
    echo Spike!
    if [ -f /tmp/a ]
    then
      exit 1
    else
      touch /tmp/a
    fi' --on-threshold continue

should print Spike! at most once, because after hitting the threshold
for the first time, /tmp/a exists, the shell action will fail, and the
continue action is not performed. However, unless /tmp/a exists before
the measurement, it will print Spike! until stopped, as the continue
flag stays set.

Set the continue flag to false in the beginning of actions_perform() to
make RTLA continue only if the action was actually performed.

Fixes: 8d933d5c89e8 ("rtla/timerlat: Add continue action")
Link: https://lore.kernel.org/r/20260526102523.2662391-1-tglozar@redhat.com
[ correct Fixes tag to include 12 characters of hash ]
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

rtla: Introduce for_each_action() helper

2026-07-24T14:15:54+00:00

[ Upstream commit 648634d17c813b35da775982662e56ea8ce750de ]

The for loop to iterate over the list of actions is used in
more than one place. To avoid code duplication and improve
readability, introduce a for_each_action() helper macro.

Replace the open-coded for loops with the new helper.

Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260106133655.249887-4-wander@redhat.com
Signed-off-by: Tomas Glozar 
Stable-dep-of: dd520daffbc9 ("rtla/actions: Restore continue flag in actions_perform()")
Signed-off-by: Sasha Levin

rtla: Fix parse_cpu_set() bug introduced by strtoi()

2026-05-23T11:07:14+00:00

[ Upstream commit 6ea8a206108fe8b5940c2797afc54ae9f5a7bbdd ]

The patch 'Replace atoi() with a robust strtoi()' introduced a bug
in parse_cpu_set(), which relies on partial parsing of the input string.

The function parses CPU specifications like '0-3,5' by incrementing
a pointer through the string. strtoi() rejects strings with trailing
characters, causing parse_cpu_set() to fail on any CPU list with
multiple entries.

Restore the original use of atoi() in parse_cpu_set().

Fixes: 7e9dfccf8f11 ("rtla: Replace atoi() with a robust strtoi()")
Signed-off-by: Costa Shulyupin 
Reviewed-by: Masami Hiramatsu (Google) 
Link: https://lore.kernel.org/r/20260112192642.212848-2-costa.shul@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

rtla/utils: Fix resource leak in set_comm_sched_attr()

2026-05-23T11:06:43+00:00

[ Upstream commit 5b6dc659ad792c72b3ff1be8039ae2945e030928 ]

The set_comm_sched_attr() function opens the /proc directory via
opendir() but fails to call closedir() on its successful exit path.
If the function iterates through all processes without error, it
returns 0 directly, leaking the DIR stream pointer.

Fix this by refactoring the function to use a single exit path. A
retval variable is introduced to track the success or failure status.
All exit points now jump to a unified out label that calls closedir()
before the function returns, ensuring the resource is always freed.

Fixes: dada03db9bb19 ("rtla: Remove procps-ng dependency")
Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260309195040.1019085-18-wander@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

rtla: Replace atoi() with a robust strtoi()

2026-05-23T11:06:43+00:00

[ Upstream commit 7e9dfccf8f11c26208211457c4597a466135b56a ]

The atoi() function does not perform error checking, which can lead to
undefined behavior when parsing invalid or out-of-range strings. This
can cause issues when parsing user-provided numerical inputs, such as
signal numbers, PIDs, or CPU lists.

To address this, introduce a new strtoi() helper function that safely
converts a string to an integer. This function validates the input and
checks for overflows, returning a negative value on  failure.

Replace all calls to atoi() with the new strtoi() function and add
proper error handling to make the parsing more robust and prevent
potential issues.

Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260106133655.249887-5-wander@redhat.com
Signed-off-by: Tomas Glozar 
Stable-dep-of: 5b6dc659ad79 ("rtla/utils: Fix resource leak in set_comm_sched_attr()")
Signed-off-by: Sasha Levin

rtla: Fix -C/--cgroup interface

2026-05-23T11:06:43+00:00

[ Upstream commit 7b71f3a6986c93defbb72bb6c143e04122720cb1 ]

Currently, user can only specify cgroup to the tracer's thread the
following ways:

    `-C[cgroup]`
    `-C[=cgroup]`
    `--cgroup[=cgroup]`

If user tries to specify cgroup as `-C [cgroup]` or `--cgroup [cgroup]`,
the parser silently fails and rtla's cgroup is used for the tracer
threads.

To make interface more user-friendly, allow user to specify cgroup in
the aforementioned way, i.e. `-C [cgroup]` and `--cgroup [cgroup]`.

Refactor identical logic between -t/--trace and -C/--cgroup into a
common function.

Change documentation to reflect this user interface change.

Fixes: a957cbc02531 ("rtla: Add -C cgroup support")
Signed-off-by: Ivan Pravdin 
Reviewed-by: Tomas Glozar 
Link: https://lore.kernel.org/r/16132f1565cf5142b5fbd179975be370b529ced7.1762186418.git.ipravdin.official@gmail.com
[ use capital letter in subject, as required by tracing subsystem ]
Signed-off-by: Tomas Glozar 
Stable-dep-of: 5b6dc659ad79 ("rtla/utils: Fix resource leak in set_comm_sched_attr()")
Signed-off-by: Sasha Levin

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