<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/tracing/rtla/src, branch linux-5.17.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>rtla: Fix __set_sched_attr error message</title>
<updated>2022-06-09T08:26:15+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2022-04-29T16:28:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e9b5510fd9e2d8e0123f66e40c565c472cdf5a78'/>
<id>e9b5510fd9e2d8e0123f66e40c565c472cdf5a78</id>
<content type='text'>
[ Upstream commit 941a53c39a151e9aceef153cdfaed0f166ba01b7 ]

rtla's function __set_sched_attr() was borrowed from stalld, but I
forgot to update the error message to something meaningful for rtla.

 Update the error message from:
        boost_with_deadline failed to boost pid PID: STRERROR
 to a proper one:
        Failed to set sched attributes to the pid PID: STRERROR

Link: https://lkml.kernel.org/r/a2d19b2c53f6512aefd1ee7f8c1bd19d4fc8b99d.1651247710.git.bristot@kernel.org
Link: https://lore.kernel.org/r/eeded730413e7feaa13f946924bcf2cbf7dd9561.1650617571.git.bristot@kernel.org/

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 941a53c39a151e9aceef153cdfaed0f166ba01b7 ]

rtla's function __set_sched_attr() was borrowed from stalld, but I
forgot to update the error message to something meaningful for rtla.

 Update the error message from:
        boost_with_deadline failed to boost pid PID: STRERROR
 to a proper one:
        Failed to set sched attributes to the pid PID: STRERROR

Link: https://lkml.kernel.org/r/a2d19b2c53f6512aefd1ee7f8c1bd19d4fc8b99d.1651247710.git.bristot@kernel.org
Link: https://lore.kernel.org/r/eeded730413e7feaa13f946924bcf2cbf7dd9561.1650617571.git.bristot@kernel.org/

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/osnoise: Fix osnoise hist stop tracing message</title>
<updated>2022-04-08T11:57:53+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2022-03-02T19:01:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=27a0a95b8add281d534c3ee41b8973b6affd8407'/>
<id>27a0a95b8add281d534c3ee41b8973b6affd8407</id>
<content type='text'>
[ Upstream commit 7d38c35167c58153e8b5bea839616d00e90564b9 ]

rtla osnoise hist is printing the following message when hitting stop
tracing:

  printf("rtla timelat hit stop tracing\n");

which is obviosly wrong.

s/timerlat/osnoise/ fixing the printf.

Link: https://lkml.kernel.org/r/2b8f090556fe37b81d183b74ce271421f131c77b.1646247211.git.bristot@kernel.org

Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode")
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: Clark Williams &lt;williams@redhat.com&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7d38c35167c58153e8b5bea839616d00e90564b9 ]

rtla osnoise hist is printing the following message when hitting stop
tracing:

  printf("rtla timelat hit stop tracing\n");

which is obviosly wrong.

s/timerlat/osnoise/ fixing the printf.

Link: https://lkml.kernel.org/r/2b8f090556fe37b81d183b74ce271421f131c77b.1646247211.git.bristot@kernel.org

Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode")
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: Clark Williams &lt;williams@redhat.com&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/osnoise: Fix error message when failing to enable trace instance</title>
<updated>2022-02-26T02:05:30+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2022-02-18T17:57:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=90f59ee41abf587ad4675a70434136c8707fdf4b'/>
<id>90f59ee41abf587ad4675a70434136c8707fdf4b</id>
<content type='text'>
When a trace instance creation fails, tools are printing:

	Could not enable -&gt; osnoiser &lt;- tracer for tracing

Print the actual (and correct) name of the tracer it fails to enable.

Link: https://lkml.kernel.org/r/53ef0582605af91eca14b19dba9fc9febb95d4f9.1645206561.git.bristot@kernel.org

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When a trace instance creation fails, tools are printing:

	Could not enable -&gt; osnoiser &lt;- tracer for tracing

Print the actual (and correct) name of the tracer it fails to enable.

Link: https://lkml.kernel.org/r/53ef0582605af91eca14b19dba9fc9febb95d4f9.1645206561.git.bristot@kernel.org

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/osnoise: Free params at the exit</title>
<updated>2022-02-26T02:05:30+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2022-02-18T17:57:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=316f710172461c501f9b73f3b2fc7ce8aa5b84a5'/>
<id>316f710172461c501f9b73f3b2fc7ce8aa5b84a5</id>
<content type='text'>
The variable that stores the parsed command line arguments are not
being free()d at the rtla osnoise top exit path.

Free params variable before exiting.

Link: https://lkml.kernel.org/r/0be31d8259c7c53b98a39769d60cfeecd8421785.1645206561.git.bristot@kernel.org

Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode")
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The variable that stores the parsed command line arguments are not
being free()d at the rtla osnoise top exit path.

Free params variable before exiting.

Link: https://lkml.kernel.org/r/0be31d8259c7c53b98a39769d60cfeecd8421785.1645206561.git.bristot@kernel.org

Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode")
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/hist: Make -E the short version of --entries</title>
<updated>2022-02-26T02:05:30+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2022-02-18T17:57:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dd48f316a1216fa10f9ba26852457794417d9bc6'/>
<id>dd48f316a1216fa10f9ba26852457794417d9bc6</id>
<content type='text'>
Currently, --entries uses -e as the short version in the hist mode of
timerlat and osnoise tools. But as -e is already used to enable events
on trace sessions by other tools, thus let's keep it available for the
same usage for all rtla tools.

Make -E the short version of --entries for hist mode on all tools.

Note: rtla was merged in this merge window, so rtla was not released yet.

Link: https://lkml.kernel.org/r/5dbf0cbe7364d3a05e708926b41a097c59a02b1e.1645206561.git.bristot@kernel.org

Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently, --entries uses -e as the short version in the hist mode of
timerlat and osnoise tools. But as -e is already used to enable events
on trace sessions by other tools, thus let's keep it available for the
same usage for all rtla tools.

Make -E the short version of --entries for hist mode on all tools.

Note: rtla was merged in this merge window, so rtla was not released yet.

Link: https://lkml.kernel.org/r/5dbf0cbe7364d3a05e708926b41a097c59a02b1e.1645206561.git.bristot@kernel.org

Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla: Fix segmentation fault when failing to enable -t</title>
<updated>2022-02-08T16:23:09+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2022-02-08T14:36:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4bbf59a9db44c78dd3e5c72057548f7c1eb8d2ba'/>
<id>4bbf59a9db44c78dd3e5c72057548f7c1eb8d2ba</id>
<content type='text'>
rtla osnoise and timerlat are causing a segmentation fault when running
with the --trace option on a kernel that does not support multiple
instances. For example:

    [root@f34 rtla]# rtla osnoise top -t
    failed to enable the tracer osnoise
    Could not enable osnoiser tracer for tracing
    Failed to enable the trace instance
    Segmentation fault (core dumped)

This error happens because the exit code of the tools is trying
to destroy the trace instance that failed to be created.

Make osnoise_destroy_tool() aware of possible NULL osnoise_tool *,
and do not attempt to destroy it. This also simplifies the exit code.

Link: https://lkml.kernel.org/r/5660a2b6bf66c2655842360f2d7f6b48db5dba23.1644327249.git.bristot@kernel.org

Suggested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode")
Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode")
Fixes: a828cd18bc4a ("rtla: Add timerlat tool and timelart top mode")
Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
rtla osnoise and timerlat are causing a segmentation fault when running
with the --trace option on a kernel that does not support multiple
instances. For example:

    [root@f34 rtla]# rtla osnoise top -t
    failed to enable the tracer osnoise
    Could not enable osnoiser tracer for tracing
    Failed to enable the trace instance
    Segmentation fault (core dumped)

This error happens because the exit code of the tools is trying
to destroy the trace instance that failed to be created.

Make osnoise_destroy_tool() aware of possible NULL osnoise_tool *,
and do not attempt to destroy it. This also simplifies the exit code.

Link: https://lkml.kernel.org/r/5660a2b6bf66c2655842360f2d7f6b48db5dba23.1644327249.git.bristot@kernel.org

Suggested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode")
Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode")
Fixes: a828cd18bc4a ("rtla: Add timerlat tool and timelart top mode")
Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/trace: Error message fixup</title>
<updated>2022-02-04T17:39:28+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2022-02-04T16:24:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1a6229096bb501495442ab47761d746c1ae791e1'/>
<id>1a6229096bb501495442ab47761d746c1ae791e1</id>
<content type='text'>
Use capital and change "tracer %s" to "%s tracer".

No functional change.

Link: https://lkml.kernel.org/r/361697d27431afefa64c67c323564205385c418d.1643990447.git.bristot@kernel.org

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use capital and change "tracer %s" to "%s tracer".

No functional change.

Link: https://lkml.kernel.org/r/361697d27431afefa64c67c323564205385c418d.1643990447.git.bristot@kernel.org

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/utils: Fix session duration parsing</title>
<updated>2022-02-04T17:39:28+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2022-02-04T16:24:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f35491b861290a2c8258b5f70f9bb5d5ed2a1c6f'/>
<id>f35491b861290a2c8258b5f70f9bb5d5ed2a1c6f</id>
<content type='text'>
Use gmtime to format the duration time. This avoids problems when the
system uses local time different of Pisa's Local Time.

Link: https://lkml.kernel.org/r/a2f0a37bc006c2561bb8ecd871cd70532b4a9f2d.1643990447.git.bristot@kernel.org

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use gmtime to format the duration time. This avoids problems when the
system uses local time different of Pisa's Local Time.

Link: https://lkml.kernel.org/r/a2f0a37bc006c2561bb8ecd871cd70532b4a9f2d.1643990447.git.bristot@kernel.org

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/timerlat: Add timerlat hist mode</title>
<updated>2022-01-13T22:02:43+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2021-12-10T18:11:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1eeb6328e8b3a917ba0be4965f272147dbd4cf55'/>
<id>1eeb6328e8b3a917ba0be4965f272147dbd4cf55</id>
<content type='text'>
The rtla hist hist mode displays a histogram of each tracer event
occurrence, both for IRQ and timer latencies. The tool also allows
many configurations of the timerlat tracer and the collection of
the tracer output.

Here is one example of the rtla timerlat hist mode output:
  ---------- %&lt; ----------
 [root@alien ~]# rtla timerlat hist -c 0-3 -d 1M
 # RTLA timerlat histogram
 # Time unit is microseconds (us)
 # Duration:   0 00:01:00
 Index   IRQ-000   Thr-000   IRQ-001   Thr-001   IRQ-002   Thr-002   IRQ-003   Thr-003
 0         58572         0     59373         0     58691         0     58895         0
 1          1422     57021       628     57241      1310     56160      1102     56805
 2             6      2931         0      2695         0      3567         4      3031
 3             1        40         0        53         0       260         0       142
 4             0         7         0         5         0         6         0        17
 5             0         2         0         5         0         7         0         4
 6             0         0         0         2         0         1         0         1
 8             0         0         0         0         0         0         0         1
 over:         0         0         0         0         0         0         0         0
 count:    60001     60001     60001     60001     60001     60001     60001     60001
 min:          0         1         0         1         0         1         0         1
 avg:          0         1         0         1         0         1         0         1
 max:          3         5         1         6         1         6         2         8
  ---------- &gt;% ----------

Running
 - rtla timerlat hist --help
provides information about the available options.

Link: https://lkml.kernel.org/r/7049ed3c46b7d6aceab18ffe7770003dfc4ddceb.1639158831.git.bristot@kernel.org

Cc: Tao Zhou &lt;tao.zhou@linux.dev&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Tom Zanussi &lt;zanussi@kernel.org&gt;
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: Clark Williams &lt;williams@redhat.com&gt;
Cc: John Kacur &lt;jkacur@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The rtla hist hist mode displays a histogram of each tracer event
occurrence, both for IRQ and timer latencies. The tool also allows
many configurations of the timerlat tracer and the collection of
the tracer output.

Here is one example of the rtla timerlat hist mode output:
  ---------- %&lt; ----------
 [root@alien ~]# rtla timerlat hist -c 0-3 -d 1M
 # RTLA timerlat histogram
 # Time unit is microseconds (us)
 # Duration:   0 00:01:00
 Index   IRQ-000   Thr-000   IRQ-001   Thr-001   IRQ-002   Thr-002   IRQ-003   Thr-003
 0         58572         0     59373         0     58691         0     58895         0
 1          1422     57021       628     57241      1310     56160      1102     56805
 2             6      2931         0      2695         0      3567         4      3031
 3             1        40         0        53         0       260         0       142
 4             0         7         0         5         0         6         0        17
 5             0         2         0         5         0         7         0         4
 6             0         0         0         2         0         1         0         1
 8             0         0         0         0         0         0         0         1
 over:         0         0         0         0         0         0         0         0
 count:    60001     60001     60001     60001     60001     60001     60001     60001
 min:          0         1         0         1         0         1         0         1
 avg:          0         1         0         1         0         1         0         1
 max:          3         5         1         6         1         6         2         8
  ---------- &gt;% ----------

Running
 - rtla timerlat hist --help
provides information about the available options.

Link: https://lkml.kernel.org/r/7049ed3c46b7d6aceab18ffe7770003dfc4ddceb.1639158831.git.bristot@kernel.org

Cc: Tao Zhou &lt;tao.zhou@linux.dev&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Tom Zanussi &lt;zanussi@kernel.org&gt;
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: Clark Williams &lt;williams@redhat.com&gt;
Cc: John Kacur &lt;jkacur@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla: Add timerlat tool and timelart top mode</title>
<updated>2022-01-13T22:02:43+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2021-12-10T18:11:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a828cd18bc4ad72ff6d64c0dd23dc814a6741fed'/>
<id>a828cd18bc4ad72ff6d64c0dd23dc814a6741fed</id>
<content type='text'>
The rtla timerlat tool is an interface for the timerlat tracer.
The timerlat tracer dispatches a kernel thread per-cpu. These threads set a
periodic timer to wake themselves up and go back to sleep. After the
wakeup, they collect and generate useful information for the debugging of
operating system timer latency.

The timerlat tracer outputs information in two ways. It periodically
prints the timer latency at the timer IRQ handler and the Thread handler.
It also provides information for each noise via the osnoise tracepoints.

The rtla timerlat top mode displays a summary of the periodic output from
the timerlat tracer.

Here is one example of the rtla timerlat tool output:
 ---------- %&lt; ----------
[root@alien ~]# rtla timerlat top -c 0-3 -d 1m
                                     Timer Latency
  0 00:01:00   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max
  0 #60001     |        0         0         0         3 |        1         1         1         6
  1 #60001     |        0         0         0         3 |        2         1         1         5
  2 #60001     |        0         0         1         6 |        1         1         2         7
  3 #60001     |        0         0         0         7 |        1         1         1        11
 ---------- &gt;% ----------

Running:
  # rtla timerlat --help
  # rtla timerlat top --help
provides information about the available options.

Link: https://lkml.kernel.org/r/e95032e20c2b88c962195bf7693bb53c9ebcced8.1639158831.git.bristot@kernel.org

Cc: Tao Zhou &lt;tao.zhou@linux.dev&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Tom Zanussi &lt;zanussi@kernel.org&gt;
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: Clark Williams &lt;williams@redhat.com&gt;
Cc: John Kacur &lt;jkacur@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The rtla timerlat tool is an interface for the timerlat tracer.
The timerlat tracer dispatches a kernel thread per-cpu. These threads set a
periodic timer to wake themselves up and go back to sleep. After the
wakeup, they collect and generate useful information for the debugging of
operating system timer latency.

The timerlat tracer outputs information in two ways. It periodically
prints the timer latency at the timer IRQ handler and the Thread handler.
It also provides information for each noise via the osnoise tracepoints.

The rtla timerlat top mode displays a summary of the periodic output from
the timerlat tracer.

Here is one example of the rtla timerlat tool output:
 ---------- %&lt; ----------
[root@alien ~]# rtla timerlat top -c 0-3 -d 1m
                                     Timer Latency
  0 00:01:00   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max
  0 #60001     |        0         0         0         3 |        1         1         1         6
  1 #60001     |        0         0         0         3 |        2         1         1         5
  2 #60001     |        0         0         1         6 |        1         1         2         7
  3 #60001     |        0         0         0         7 |        1         1         1        11
 ---------- &gt;% ----------

Running:
  # rtla timerlat --help
  # rtla timerlat top --help
provides information about the available options.

Link: https://lkml.kernel.org/r/e95032e20c2b88c962195bf7693bb53c9ebcced8.1639158831.git.bristot@kernel.org

Cc: Tao Zhou &lt;tao.zhou@linux.dev&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Tom Zanussi &lt;zanussi@kernel.org&gt;
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: Clark Williams &lt;williams@redhat.com&gt;
Cc: John Kacur &lt;jkacur@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
