linux-stable.git/Documentation/tools/rtla/common_timerlat_options.rst, branch master

Documentation/rtla: rename common_xxx.rst files to common_xxx.txt

2025-10-17T20:25:12+00:00

Sphinx reports htmldocs errors:

Documentation/tools/rtla/common_options.rst:58: ERROR: Undefined substitution referenced: "threshold".
Documentation/tools/rtla/common_options.rst:88: ERROR: Undefined substitution referenced: "tool".
Documentation/tools/rtla/common_options.rst:88: ERROR: Undefined substitution referenced: "thresharg".
Documentation/tools/rtla/common_options.rst:88: ERROR: Undefined substitution referenced: "tracer".
Documentation/tools/rtla/common_options.rst:92: ERROR: Undefined substitution referenced: "tracer".
Documentation/tools/rtla/common_options.rst:98: ERROR: Undefined substitution referenced: "actionsperf".
Documentation/tools/rtla/common_options.rst:113: ERROR: Undefined substitution referenced: "tool".

common_*.rst files are snippets that are intended to be included by rtla
docs (rtla*.rst). common_options.rst in particular contains
substitutions which depend on other common_* includes, so building it
independently as reST source results in above errors.

Rename all common_*.rst files to common_*.txt to prevent Sphinx from
building these snippets as standalone reST source and update all include
references accordingly.

Link: https://www.sphinx-doc.org/en/master/usage/restructuredtext/basics.html#substitutions
Suggested-by: Tomas Glozar 
Suggested-by: Bagas Sanjaya 
Signed-off-by: Gopi Krishna Menon 
Reviewed-by: Tomas Glozar 
Fixes: 05b7e10687c6 ("tools/rtla: Add remaining support for osnoise actions")
Reviewed-by: Bagas Sanjaya 
Link: https://lore.kernel.org/r/20251008184522.13201-1-krishnagopi487@gmail.com
[Bagas: massage commit message and apply trailers]
Signed-off-by: Bagas Sanjaya 
Reviewed-by: Randy Dunlap 
Tested-by: Randy Dunlap 
Signed-off-by: Jonathan Corbet 
Message-ID: <20251013092719.30780-2-bagasdotme@gmail.com>

tools/rtla: Add remaining support for osnoise actions

2025-09-27T08:53:48+00:00

The basic functionality came with the consolidation; now hook up the
command line options, and add documentation and tests.

Cc: John Kacur 
Cc: Costa Shulyupin 
Link: https://lore.kernel.org/20250907022325.243930-8-crwood@redhat.com
Reviewed-by: Tomas Glozar  
Signed-off-by: Crystal Wood 
Signed-off-by: Steven Rostedt (Google)

Documentation/rtla: Add actions feature

2025-07-25T20:43:57+00:00

Document both --on-threshold and --on-end, with examples.

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/20250626123405.1496931-10-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google)

rtla: Documentation: Mention --deepest-idle-state

2024-10-17T21:13:16+00:00

Add --deepest-idle-state to manpage and mention libcpupower dependency
in README.txt.

Link: https://lore.kernel.org/20241017140914.3200454-7-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google)

rtla: Documentation: Fix -t, --trace

2024-05-16T14:52:16+00:00

Move -t, --trace from common_options.rst to
common_osnoise_options.rst and
common_timerlat_options.rst

so that it will appear in the man pages

rtla-timerlat-hist.1
rtla-timerlat-top.1
rtla-osnoise-hist.1
rtla-osnoise-top.1

Remove the equals ('=') sign and add a space.

Link: https://lkml.kernel.org/r/20240516143121.12614-1-jkacur@redhat.com

Cc: Daniel Bristot de Oliveria 
Signed-off-by: John Kacur 
Signed-off-by: Daniel Bristot de Oliveira

rtla/timerlat: Make user-space threads the default

2024-05-15T13:13:57+00:00

After ther -u addition, most of the known users are setting it. And
it makes sense, as it adds more information, and inherits the default
setup for the threads - e.g., cgroups configs.

Thus, if the user-space interface is available, enable -u. Otherwise,
use the in-kernel thread.

Add the -k option to allow the user to request kernel-threads.

Link: https://lkml.kernel.org/r/9241d3089de4091b124f780ed832a0e6646cadaa.1713968967.git.bristot@kernel.org

Cc: Jonathan Corbet 
Cc: Juri Lelli 
Signed-off-by: Daniel Bristot de Oliveira

tools/rtla: Add -U/--user-load option to timerlat

2024-03-20T04:39:06+00:00

The timerlat tracer provides an interface for any application to wait
for the timerlat's periodic wakeup. Currently, rtla timerlat uses it
to dispatch its user-space workload (-u option).

But as the tracer interface is generic, rtla timerlat can also be used
to monitor any workload that uses it. For example, a user might
place their own workload to wait on the tracer interface, and
monitor the results with rtla timerlat.

Add the -U option to rtla timerlat top and hist. With this option, rtla
timerlat will not dispatch its workload but only setting up the
system, waiting for a user to dispatch its workload.

The sample code in this patch is an example of python application
that loops in the timerlat tracer fd.

To use it, dispatch:

 # rtla timerlat -U

In a terminal, then run the python program on another terminal,
specifying the CPU to run it. For example, setting on CPU 1:

 #./timerlat_load.py 1

Then rtla timerlat will start printing the statistics of the
./timerlat_load.py app.

An interesting point is that the "Ret user Timer Latency" value
is the overall response time of the load. The sample load does
a memory copy to exemplify that.

The stop tracing options on rtla timerlat works in this setup
as well, including auto analysis.

Link: https://lkml.kernel.org/r/36e6bcf18fe15c7601048fd4c65aeb193c502cc8.1707229706.git.bristot@kernel.org

Cc: Jonathan Corbet 
Cc: Masami Hiramatsu 
Signed-off-by: Daniel Bristot de Oliveira

Documentation: Add tools/rtla timerlat -u option documentation

2023-06-13T20:43:37+00:00

Add the -u/--user-thread option documentation for timerlat top/hist.

Link: https://lkml.kernel.org/r/bf727c8ccb8f50792200ae620141e047edf4af7a.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)

rtla/timerlat: Add --dma-latency option

2022-03-15T18:36:50+00:00

Add the --dma-latency to set /dev/cpu_dma_latency to the
specified value, this aims to avoid having exit from idle
states latencies that could be influencing the analysis.

Link: https://lkml.kernel.org/r/72ddb0d913459f13217086dadafad88a7c46dd28.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira 
Cc: Clark Williams 
Cc: Juri Lelli 
Cc: Jonathan Corbet 
Signed-off-by: Daniel Bristot de Oliveira 
Signed-off-by: Steven Rostedt (Google)

rtla/timerlat: Add the automatic trace option

2022-03-15T18:36:49+00:00

Add the -a/--auto  option. This option sets some commonly
used options while debugging the system. It aims to help users produce
reports in the field, reducing the number of arguments passed to the
tool in the first approach to a problem.

It is equivalent to setting osnoise/stop_tracing_total_us and print_stack
with the argument, and saving the trace to timerlat_trace.txt file if the
trace is stopped automatically.

Link: https://lkml.kernel.org/r/92438f7ef132c731f538cebdf77850300afe04a5.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira 
Cc: Clark Williams 
Cc: Juri Lelli 
Cc: Jonathan Corbet 
Signed-off-by: Daniel Bristot de Oliveira 
Signed-off-by: Steven Rostedt (Google)