kernel/linux.git/tools/tracing/rtla/src/utils.h, branch v7.0-rc7

rtla: Use standard exit codes for result enum

2026-01-07T14:57:55+00:00

The result enum defines custom values for PASSED, ERROR, and FAILED. These values correspond to standard exit codes EXIT_SUCCESS and EXIT_FAILURE. Update the enum to use the standard macros EXIT_SUCCESS and EXIT_FAILURE to improve readability and adherence to standard C practices. The FAILED value is implicitly assigned EXIT_FAILURE + 1, so there is no need to assign an explicit value. Signed-off-by: Wander Lairson Costa Link: https://lore.kernel.org/r/20260106133655.249887-9-wander@redhat.com Signed-off-by: Tomas Glozar

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

2026-01-07T14:57:55+00:00

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

tools/rtla: Remove unused function declarations

2026-01-06T09:11:59+00:00

Historically four function declarations remain orphaned or duplicated. Remove them to keep the source clean. Signed-off-by: Costa Shulyupin Link: https://lore.kernel.org/r/20251012071133.290225-1-costa.shul@redhat.com Signed-off-by: Tomas Glozar

rtla: Fix -C/--cgroup interface

2025-11-21T09:30:27+00:00

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

tools/rtla: Add fatal() and replace error handling pattern

2025-11-21T09:30:27+00:00

The code contains some technical debt in error handling, which complicates the consolidation of duplicated code. Introduce an fatal() function to replace the common pattern of err_msg() followed by exit(EXIT_FAILURE), reducing the length of an already long function. Further patches using fatal() follow. Signed-off-by: Costa Shulyupin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/20251011082738.173670-2-costa.shul@redhat.com Signed-off-by: Tomas Glozar

rtla: Set distinctive exit value for failed tests

2025-05-07T19:36:19+00:00

A test is considered failed when a sample trace exceeds the threshold. Failed tests return the same exit code as passed tests, requiring test frameworks to determine the result by searching for "hit stop tracing" in the output. Assign a distinct exit code for failed tests to enable the use of shell expressions and seamless integration with testing frameworks without the need to parse output. Add enum type for return value. Update `make check`. Cc: Daniel Bristot de Oliveira Cc: John Kacur Cc: "Luis Claudio R. Goncalves" Cc: Eder Zulian Cc: Dan Carpenter Cc: Jan Stancek Link: https://lore.kernel.org/20250417185757.2194541-1-costa.shul@redhat.com Signed-off-by: Costa Shulyupin Reviewed-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)

rtla/utils: Add idle state disabling via libcpupower

2024-10-17T21:13:15+00:00

Add functions to utils.c to disable idle states through functions of libcpupower. This will serve as the basis for disabling idle states per cpu when running timerlat. Link: https://lore.kernel.org/20241017140914.3200454-4-tglozar@redhat.com Signed-off-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)

tools/rtla: fix collision with glibc sched_attr/sched_set_attr

2024-10-11T00:31:48+00:00

glibc commit 21571ca0d703 ("Linux: Add the sched_setattr and sched_getattr functions") now also provides 'struct sched_attr' and sched_setattr() which collide with the ones from rtla. In file included from src/trace.c:11: src/utils.h:49:8: error: redefinition of ‘struct sched_attr’ 49 | struct sched_attr { | ^~~~~~~~~~ In file included from /usr/include/bits/sched.h:60, from /usr/include/sched.h:43, from /usr/include/tracefs/tracefs.h:10, from src/trace.c:4: /usr/include/linux/sched/types.h:98:8: note: originally defined here 98 | struct sched_attr { | ^~~~~~~~~~ Define 'struct sched_attr' conditionally, similar to what strace did: https://lore.kernel.org/all/20240930222913.3981407-1-raj.khem@gmail.com/ and rename rtla's version of sched_setattr() to avoid collision. Link: https://lore.kernel.org/8088f66a7a57c1b209cd8ae0ae7c336a7f8c930d.1728572865.git.jstancek@redhat.com Signed-off-by: Jan Stancek Signed-off-by: Steven Rostedt (Google)

tools/rtla: Replace setting prio with nice for SCHED_OTHER

2024-02-12T09:56:36+00:00

Since the sched_priority for SCHED_OTHER is always 0, it makes no sence to set it. Setting nice for SCHED_OTHER seems more meaningful. Link: https://lkml.kernel.org/r/20240207065142.1753909-1-limingming3@lixiang.com Cc: stable@vger.kernel.org Fixes: b1696371d865 ("rtla: Helper functions for rtla") Signed-off-by: limingming3 Signed-off-by: Daniel Bristot de Oliveira

rtla/timerlat_top: Add timerlat user-space support

2023-06-13T20:38:51+00:00

Add the support for running timerlat threads in user-space. In this mode, enabled with -u/--user-threads, timerlat dispatches user-space processes that will loop in the timerlat_fd, measuring the overhead for going to user-space and then returning to the kernel - in addition to the existing measurements. Here is one example of the tool's output with -u enabled: $ sudo timerlat top -u -d 600 -q Timer Latency 0 00:10:01 | IRQ Timer Latency (us) | Thread Timer Latency (us) | Ret user Timer Latency (us) CPU COUNT | cur min avg max | cur min avg max | cur min avg max 0 #600001 | 0 0 0 3 | 2 1 2 9 | 3 2 3 15 1 #600001 | 0 0 0 2 | 2 1 2 13 | 2 2 3 18 2 #600001 | 0 0 0 10 | 2 1 2 16 | 3 2 3 20 3 #600001 | 0 0 0 7 | 2 1 2 10 | 3 2 3 11 4 #600000 | 0 0 0 16 | 2 1 2 41 | 3 2 3 58 5 #600000 | 0 0 0 3 | 2 1 2 10 | 3 2 3 13 6 #600000 | 0 0 0 5 | 2 1 2 7 | 3 2 3 10 7 #600000 | 0 0 0 1 | 2 1 2 7 | 3 2 3 10 The tuning setup like -p or -C work for the user-space threads as well. Link: https://lkml.kernel.org/r/758ad2292a0a1d884138d08219e1a0f572d257a2.1686066600.git.bristot@kernel.org Cc: William White Cc: Jonathan Corbet Tested-by: Juri Lelli Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google)