linux.git/tools/tracing, branch v7.2-rc6

rtla/timerlat_top: Fix on-threshold actions firing on signal

2026-07-21T13:42:08+00:00

A bug was reported when rtla-timerlat-top tool performs on-threshold
actions, even though no threshold was hit. This is reproduced even if no
threshold is set at all:

$ rtla timerlat top -q -c 0 --on-threshold shell,command='echo BAD'
BAD
                                     Timer Latency
...

The bug is due to incorrect logic in timerlat_top_bpf_main_loop().
The loop uses timerlat_bpf_wait(), the return values of which are:

- > 0 (number of ringbuffer entries): at least 1 CPU hit threshold
- = 0: time out
- < 0: wait was interrupted by a signal

Commit 3138df6f0cd0 ("rtla/timerlat: Exit top main loop on any non-zero
wait_retval") changed the condition for "threshold hit" from
"wait_reval == 1" (exactly 1 CPU hit threshold) to "wait_retval != 0",
to fix a race where multiple CPUs hit the threshold at the same time.

That also made it incorrectly include a signal (< 0), coming from either
duration expired (SIGALRM) or user interrupt (SIGINT).

Check for wait_retval greater than zero in the if condition to cover all
return values correctly.

Fixes: 3138df6f0cd0 ("rtla/timerlat: Exit top main loop on any non-zero wait_retval")
Reported-by: Attila Fazekas 
Reviewed-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260713141047.687877-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar

rtla: Also link in ctype.c

2026-07-08T08:38:18+00:00

rtla started to only link parts of the tools library. It now misses the
ctype information used by all the related string operations. Just add
another single file to make it build again.

Signed-off-by: Bastian Blank 
Fixes: 48209d763c22 ("rtla: Add libsubcmd dependency")
Link: https://lore.kernel.org/r/ako2S4mzIqWwYuas@steamhammer.waldi.eu.org
[ remove duplicated spaces in commit message ]
Signed-off-by: Tomas Glozar

rtla: Fix missing unistd include

2026-07-07T13:58:36+00:00

Compiling RTLA 7.1.x with GCC 16 and uClibc as standard library fails
with these errors:

src/common.c: In function ‘set_signals’:
src/common.c:40:17: error: implicit declaration of function ‘alarm’ [-Wimplicit-function-declaration]
   40 |                 alarm(params->duration);
      |                 ^~~~~
src/common.c: In function ‘common_apply_config’:
src/common.c:187:44: error: implicit declaration of function ‘getpid’; did you mean ‘getpt’? [-Wimplicit-function-declaration]
  187 |                 retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set),
      |                                            ^~~~~~
      |                                            getpt
In file included from src/common.c:9:
src/common.c: In function ‘run_tool’:
src/common.c:262:19: error: implicit declaration of function ‘sysconf’; did you mean ‘sscanf’? [-Wimplicit-function-declaration]
  262 |         nr_cpus = get_nprocs_conf();
      |                   ^~~~~~~~~~~~~~~
src/common.c:262:19: error: ‘_SC_NPROCESSORS_CONF’ undeclared (first use in this function)
  262 |         nr_cpus = get_nprocs_conf();
      |                   ^~~~~~~~~~~~~~~
src/common.c:262:19: note: each undeclared identifier is reported only once for each function it appears in
src/common.c:370:17: error: implicit declaration of function ‘sleep’ [-Wimplicit-function-declaration]
  370 |                 sleep(1);
      |                 ^~~~~

Restore the missing unistd.h include.

Fixes: 115b06a00875 ("tools/rtla: Consolidate nr_cpus usage across all tools")
Signed-off-by: Andreas Ziegler 
Link: https://lore.kernel.org/r/20260624033342.129970-1-br025@umbiko.net
[ capital letter in patch subject, remove EOL after Fixes ]
Signed-off-by: Tomas Glozar

rtla/tests: Fix pgrep filter in get_workload_pids.sh

2026-06-17T14:26:44+00:00

Multiple runtime tests in RTLA rely on the get_workload_pids() shell
helper function to get the PIDs of both kernel and user workloads.

On some systems (e.g. Fedora 43), pgrep matches kernel thread names
including square brackets: "[osnoise/0]"; on other systems (e.g.
RHEL 9.8), brackets are not included: "osnoise/0".

Accept both as valid workload PIDs rather that just the non-bracket form
to make the tests work on all systems.

Fixes: a98dad63cda3 ("rtla/tests: Add runtime test for -k and -u options")
Reported-by: Crystal Wood 
Link: https://lore.kernel.org/r/20260604140547.3616495-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar

rtla: Fix and clean up .gitignore

2026-06-17T14:26:44+00:00

.gitignore includes several entries prone to unwanted matches in
subdirectories. One of them, the recently added "lib/", matches the
recently added directory "tests/scripts/lib/" in addition to the
intended top-level "lib/", which contains object files built from
sources in tools/lib.

Add "/" to all .gitignore entries that are intended to only match
top-level files or directories: rtla, rtla_static, unit_tests,
libsubcmd/.

Remove .gitignore entries that are not needed at all:

- lib/ (contains only object files, ignored by top-level .gitignore
  already).
- .txt rtla output files added to .gitignore in commit 02689ae385c5
  ("rtla: Add generated output files to gitignore"). Since commit
  ad5b50a0959f ("rtla/tests: Run runtime tests in temporary directory"),
  those are created in a temporary directory, not in tools/tracing/rtla.

Keeping libsubcmd/ as that contains other generated files (headers,
archives, etc.).

Fixes: 48209d763c22 ("rtla: Add libsubcmd dependency")
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202605291919.eszupseg-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202605300436.PqQ0Bc8q-lkp@intel.com/
Link: https://lore.kernel.org/r/20260601091835.3118094-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar

rtla: Document tests in README

2026-05-29T07:40:54+00:00

RTLA tests are not documented anywhere. Mention both runtime and unit
tests in the README, with instructions on how to run them and a list of
dependencies and required system configuration.

Link: https://lore.kernel.org/r/20260514073038.204428-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar

rtla/tests: Add unit tests for -A/--aligned option

2026-05-28T11:02:48+00:00

Add both parse_args() and opt_* tests for the newly added -A/--aligned
option.

Assisted-by: Claude:claude-4.5-opus-high-thinking
Link: https://lore.kernel.org/r/20260527144928.2944472-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar

rtla/timerlat: Add -A/--aligned CLI option

2026-05-28T11:02:48+00:00

Add a new option, -A/--aligned, that enables timerlat thread alignment
implemented on the kernel-side in commit 4245bf4dc58f ("tracing/osnoise:
Add option to align tlat threads"). The option takes an argument,
representing alignment between timerlat threads in microseconds.

The feature is modeled after the option of the same name in the
cyclictest tool.

Link: https://lore.kernel.org/r/20260527144928.2944472-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar

rtla/tests: Add unit tests for CLI option callbacks

2026-05-28T11:02:48+00:00

In addition to testing all tool_parse_args() functions, test also all
callbacks used for parsing custom option formats.

The callbacks represent a middle layer between the parsing functions
and utility functions dedicated to checking specific argument formats,
for example, scheduling class and duration. Callback tests are run
before parsing functions to make sure any issue in the former is
reported before it is encountered through the latter.

Tests verify both successful parsing and proper rejection of invalid
inputs (via exit tests). To enable testing static callbacks, a pragma
once guard is added to timerlat.h for safe inclusion by cli_p.h.

Add dependency of UNIT_TESTS_IN on LIBSUBCMD_INCLUDES, as the new test
file tests/unit/cli_opt_callback.c includes cli_p.h which includes
subcmd/parse-options.h.

Link: https://lore.kernel.org/r/20260528103254.2990068-7-tglozar@redhat.com
Signed-off-by: Tomas Glozar

rtla/tests: Add unit tests for _parse_args() functions

2026-05-28T11:02:48+00:00

Add a test suite for the _parse_args() function of each tool that checks
the params structures (struct common_params, struct osnoise_params,
struct timerlat_params) returned by them for correctness.

One test case is added per option, as well as a few special cases for
tricky combinations of options. Test cases are ordered the same as the
option arrays and help message to allow easy checking of whether all
options are covered.

This should help clarify what the proper command line behavior of RTLA
is in case there are holes in the documentation and verify that the
intended behavior is implemented correctly.

A few necessary changes to the unit tests were done as part of this
commit:

- Unit tests now also link to libsubcmd and its dependencies.
- A new global variable in_unit_test is added to RTLA's CLI interface,
  causing it to skip check for root if running in unit tests. This
  allows the CLI unit tests to run as non-root, like existing unit
  tests.

There is quite a lot of duplication, some of it is mitigated with macros,
but partially it is intentional so that future changes in behavior are
tracked across tools.

Link: https://lore.kernel.org/r/20260528103254.2990068-6-tglozar@redhat.com
Signed-off-by: Tomas Glozar