<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/tracing/rtla, branch v6.6.76</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>rtla/timerlat: Make timerlat_hist_cpu-&gt;*_count unsigned long long</title>
<updated>2024-12-19T17:11:26+00:00</updated>
<author>
<name>Tomas Glozar</name>
<email>tglozar@redhat.com</email>
</author>
<published>2024-10-11T12:10:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a574145ef474b5ab08f86e330d7823177ec5a07b'/>
<id>a574145ef474b5ab08f86e330d7823177ec5a07b</id>
<content type='text'>
commit 76b3102148135945b013797fac9b206273f0f777 upstream.

Do the same fix as in previous commit also for timerlat-hist.

Link: https://lore.kernel.org/20241011121015.2868751-2-tglozar@redhat.com
Reported-by: Attila Fazekas &lt;afazekas@redhat.com&gt;
Signed-off-by: Tomas Glozar &lt;tglozar@redhat.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
[ Drop hunk fixing printf in timerlat_print_stats_all since that is not in 6.6 ]
Signed-off-by: Tomas Glozar &lt;tglozar@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 76b3102148135945b013797fac9b206273f0f777 upstream.

Do the same fix as in previous commit also for timerlat-hist.

Link: https://lore.kernel.org/20241011121015.2868751-2-tglozar@redhat.com
Reported-by: Attila Fazekas &lt;afazekas@redhat.com&gt;
Signed-off-by: Tomas Glozar &lt;tglozar@redhat.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
[ Drop hunk fixing printf in timerlat_print_stats_all since that is not in 6.6 ]
Signed-off-by: Tomas Glozar &lt;tglozar@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/timerlat: Make timerlat_top_cpu-&gt;*_count unsigned long long</title>
<updated>2024-12-14T19:00:10+00:00</updated>
<author>
<name>Tomas Glozar</name>
<email>tglozar@redhat.com</email>
</author>
<published>2024-10-11T12:10:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=77c9ad0c425afc4a295d8fa48b4b723851d04048'/>
<id>77c9ad0c425afc4a295d8fa48b4b723851d04048</id>
<content type='text'>
[ Upstream commit 4eba4723c5254ba8251ecb7094a5078d5c300646 ]

Most fields of struct timerlat_top_cpu are unsigned long long, but the
fields {irq,thread,user}_count are int (32-bit signed).

This leads to overflow when tracing on a large number of CPUs for a long
enough time:
$ rtla timerlat top -a20 -c 1-127 -d 12h
...
  0 12:00:00   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max
 1 #43200096  |        0         0         1         2 |        3         2         6        12
...
127 #43200096  |        0         0         1         2 |        3         2         5        11
ALL #119144 e4 |                  0         5         4 |                  2        28        16

The average latency should be 0-1 for IRQ and 5-6 for thread, but is
reported as 5 and 28, about 4 to 5 times more, due to the count
overflowing when summed over all CPUs: 43200096 * 127 = 5486412192,
however, 1191444898 (= 5486412192 mod MAX_INT) is reported instead, as
seen on the last line of the output, and the averages are thus ~4.6
times higher than they should be (5486412192 / 1191444898 = ~4.6).

Fix the issue by changing {irq,thread,user}_count fields to unsigned
long long, similarly to other fields in struct timerlat_top_cpu and to
the count variable in timerlat_top_print_sum.

Link: https://lore.kernel.org/20241011121015.2868751-1-tglozar@redhat.com
Reported-by: Attila Fazekas &lt;afazekas@redhat.com&gt;
Signed-off-by: Tomas Glozar &lt;tglozar@redhat.com&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 4eba4723c5254ba8251ecb7094a5078d5c300646 ]

Most fields of struct timerlat_top_cpu are unsigned long long, but the
fields {irq,thread,user}_count are int (32-bit signed).

This leads to overflow when tracing on a large number of CPUs for a long
enough time:
$ rtla timerlat top -a20 -c 1-127 -d 12h
...
  0 12:00:00   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max
 1 #43200096  |        0         0         1         2 |        3         2         6        12
...
127 #43200096  |        0         0         1         2 |        3         2         5        11
ALL #119144 e4 |                  0         5         4 |                  2        28        16

The average latency should be 0-1 for IRQ and 5-6 for thread, but is
reported as 5 and 28, about 4 to 5 times more, due to the count
overflowing when summed over all CPUs: 43200096 * 127 = 5486412192,
however, 1191444898 (= 5486412192 mod MAX_INT) is reported instead, as
seen on the last line of the output, and the averages are thus ~4.6
times higher than they should be (5486412192 / 1191444898 = ~4.6).

Fix the issue by changing {irq,thread,user}_count fields to unsigned
long long, similarly to other fields in struct timerlat_top_cpu and to
the count variable in timerlat_top_print_sum.

Link: https://lore.kernel.org/20241011121015.2868751-1-tglozar@redhat.com
Reported-by: Attila Fazekas &lt;afazekas@redhat.com&gt;
Signed-off-by: Tomas Glozar &lt;tglozar@redhat.com&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>tools/rtla: fix collision with glibc sched_attr/sched_set_attr</title>
<updated>2024-12-14T19:00:10+00:00</updated>
<author>
<name>Jan Stancek</name>
<email>jstancek@redhat.com</email>
</author>
<published>2024-10-10T15:09:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=987abe82faa9de05271a59a48aa0f7de6f88cf1d'/>
<id>987abe82faa9de05271a59a48aa0f7de6f88cf1d</id>
<content type='text'>
[ Upstream commit 0eecee340672c4b512f6f4a8c6add26df05d130c ]

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 &lt;jstancek@redhat.com&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 0eecee340672c4b512f6f4a8c6add26df05d130c ]

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 &lt;jstancek@redhat.com&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: Fix the help text in osnoise and timerlat top tools</title>
<updated>2024-10-10T09:58:00+00:00</updated>
<author>
<name>Eder Zulian</name>
<email>ezulian@redhat.com</email>
</author>
<published>2024-08-13T15:58:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=310d953167914e0f1412e75fe5676f4e1915f319'/>
<id>310d953167914e0f1412e75fe5676f4e1915f319</id>
<content type='text'>
commit 3d7b8ea7a8a20a45d019382c4dc6ed79e8bb95cf upstream.

The help text in osnoise top and timerlat top had some minor errors
and omissions. The -d option was missing the 's' (second) abbreviation and
the error message for '-d' used '-D'.

Cc: stable@vger.kernel.org
Fixes: 1eceb2fc2ca54 ("rtla/osnoise: Add osnoise top mode")
Fixes: a828cd18bc4ad ("rtla: Add timerlat tool and timelart top mode")
Link: https://lore.kernel.org/20240813155831.384446-1-ezulian@redhat.com
Suggested-by: Tomas Glozar &lt;tglozar@redhat.com&gt;
Reviewed-by: Tomas Glozar &lt;tglozar@redhat.com&gt;
Signed-off-by: Eder Zulian &lt;ezulian@redhat.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 3d7b8ea7a8a20a45d019382c4dc6ed79e8bb95cf upstream.

The help text in osnoise top and timerlat top had some minor errors
and omissions. The -d option was missing the 's' (second) abbreviation and
the error message for '-d' used '-D'.

Cc: stable@vger.kernel.org
Fixes: 1eceb2fc2ca54 ("rtla/osnoise: Add osnoise top mode")
Fixes: a828cd18bc4ad ("rtla: Add timerlat tool and timelart top mode")
Link: https://lore.kernel.org/20240813155831.384446-1-ezulian@redhat.com
Suggested-by: Tomas Glozar &lt;tglozar@redhat.com&gt;
Reviewed-by: Tomas Glozar &lt;tglozar@redhat.com&gt;
Signed-off-by: Eder Zulian &lt;ezulian@redhat.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/osnoise: Prevent NULL dereference in error handling</title>
<updated>2024-08-29T15:33:14+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@linaro.org</email>
</author>
<published>2024-08-09T12:34:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=753f1745146e03abd17eec8eee95faffc96d743d'/>
<id>753f1745146e03abd17eec8eee95faffc96d743d</id>
<content type='text'>
commit 90574d2a675947858b47008df8d07f75ea50d0d0 upstream.

If the "tool-&gt;data" allocation fails then there is no need to call
osnoise_free_top() and, in fact, doing so will lead to a NULL dereference.

Cc: stable@vger.kernel.org
Cc: John Kacur &lt;jkacur@redhat.com&gt;
Cc: "Luis Claudio R. Goncalves" &lt;lgoncalv@redhat.com&gt;
Cc: Clark Williams &lt;williams@redhat.com&gt;
Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode")
Link: https://lore.kernel.org/f964ed1f-64d2-4fde-ad3e-708331f8f358@stanley.mountain
Signed-off-by: Dan Carpenter &lt;dan.carpenter@linaro.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 90574d2a675947858b47008df8d07f75ea50d0d0 upstream.

If the "tool-&gt;data" allocation fails then there is no need to call
osnoise_free_top() and, in fact, doing so will lead to a NULL dereference.

Cc: stable@vger.kernel.org
Cc: John Kacur &lt;jkacur@redhat.com&gt;
Cc: "Luis Claudio R. Goncalves" &lt;lgoncalv@redhat.com&gt;
Cc: Clark Williams &lt;williams@redhat.com&gt;
Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode")
Link: https://lore.kernel.org/f964ed1f-64d2-4fde-ad3e-708331f8f358@stanley.mountain
Signed-off-by: Dan Carpenter &lt;dan.carpenter@linaro.org&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/auto-analysis: Replace \t with spaces</title>
<updated>2024-06-21T12:38:42+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2024-04-24T14:36:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=42524cc5feef81d51fce1b1c277bb12afb02a093'/>
<id>42524cc5feef81d51fce1b1c277bb12afb02a093</id>
<content type='text'>
commit a40e5e4dd0207485dee75e2b8e860d5853bcc5f7 upstream.

When copying timerlat auto-analysis from a terminal to some web pages or
chats, the \t are being replaced with a single ' ' or '    ', breaking
the output.

For example:
  ## CPU 3 hit stop tracing, analyzing it ##
    IRQ handler delay:                        1.30 us (0.11 %)
    IRQ latency:           1.90 us
    Timerlat IRQ duration:         3.00 us (0.24 %)
    Blocking thread:       1223.16 us (99.00 %)
                     insync:4048         1223.16 us
    IRQ interference          4.93 us (0.40 %)
                local_timer:236        4.93 us
  ------------------------------------------------------------------------
     Thread latency:       1235.47 us (100%)

Replace \t with spaces to avoid this problem.

Link: https://lkml.kernel.org/r/ec7ed2b2809c22ab0dfc8eb7c805ab9cddc4254a.1713968967.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Fixes: 27e348b221f6 ("rtla/timerlat: Add auto-analysis core")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a40e5e4dd0207485dee75e2b8e860d5853bcc5f7 upstream.

When copying timerlat auto-analysis from a terminal to some web pages or
chats, the \t are being replaced with a single ' ' or '    ', breaking
the output.

For example:
  ## CPU 3 hit stop tracing, analyzing it ##
    IRQ handler delay:                        1.30 us (0.11 %)
    IRQ latency:           1.90 us
    Timerlat IRQ duration:         3.00 us (0.24 %)
    Blocking thread:       1223.16 us (99.00 %)
                     insync:4048         1223.16 us
    IRQ interference          4.93 us (0.40 %)
                local_timer:236        4.93 us
  ------------------------------------------------------------------------
     Thread latency:       1235.47 us (100%)

Replace \t with spaces to avoid this problem.

Link: https://lkml.kernel.org/r/ec7ed2b2809c22ab0dfc8eb7c805ab9cddc4254a.1713968967.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Fixes: 27e348b221f6 ("rtla/timerlat: Add auto-analysis core")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/timerlat: Simplify "no value" printing on top</title>
<updated>2024-06-21T12:38:42+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2024-04-24T14:36:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d32f12e157327c47967bb153c28508b1166db072'/>
<id>d32f12e157327c47967bb153c28508b1166db072</id>
<content type='text'>
commit 5f0769331a965675cdfec97c09f3f6e875d7c246 upstream.

Instead of printing three times the same output, print it only once,
reducing lines and being sure that all no values have the same length.

It also fixes an extra '\n' when running the with kernel threads, like
here:

     =============== %&lt; ==============
                                      Timer Latency

   0 00:00:01   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
 CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max
   2 #0         |        -         -         -         - |      161       161       161       161
   3 #0         |        -         -         -         - |      161       161       161       161
   8 #1         |       54        54        54        54 |        -         -         -         -'\n'

 ---------------|----------------------------------------|---------------------------------------
 ALL #1      e0 |                 54        54        54 |                161       161       161
     =============== %&lt; ==============

This '\n' should have been removed with the user-space support that
added another '\n' if not running with kernel threads.

Link: https://lkml.kernel.org/r/0a4d8085e7cd706733a5dc10a81ca38b82bd4992.1713968967.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Fixes: cdca4f4e5e8e ("rtla/timerlat_top: Add timerlat user-space support")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5f0769331a965675cdfec97c09f3f6e875d7c246 upstream.

Instead of printing three times the same output, print it only once,
reducing lines and being sure that all no values have the same length.

It also fixes an extra '\n' when running the with kernel threads, like
here:

     =============== %&lt; ==============
                                      Timer Latency

   0 00:00:01   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
 CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max
   2 #0         |        -         -         -         - |      161       161       161       161
   3 #0         |        -         -         -         - |      161       161       161       161
   8 #1         |       54        54        54        54 |        -         -         -         -'\n'

 ---------------|----------------------------------------|---------------------------------------
 ALL #1      e0 |                 54        54        54 |                161       161       161
     =============== %&lt; ==============

This '\n' should have been removed with the user-space support that
added another '\n' if not running with kernel threads.

Link: https://lkml.kernel.org/r/0a4d8085e7cd706733a5dc10a81ca38b82bd4992.1713968967.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Fixes: cdca4f4e5e8e ("rtla/timerlat_top: Add timerlat user-space support")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rtla/timerlat: Fix histogram report when a cpu count is 0</title>
<updated>2024-06-16T11:47:42+00:00</updated>
<author>
<name>John Kacur</name>
<email>jkacur@redhat.com</email>
</author>
<published>2024-05-10T19:03:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=35c8cf7b8a71e66b690d9534791c2f258f9e94c9'/>
<id>35c8cf7b8a71e66b690d9534791c2f258f9e94c9</id>
<content type='text'>
commit 01b05fc0e5f3aec443a9a8ffa0022cbca2fd3608 upstream.

On short runs it is possible to get no samples on a cpu, like this:

  # rtla timerlat hist -u -T50

  Index   IRQ-001   Thr-001   Usr-001   IRQ-002   Thr-002   Usr-002
  2             1         0         0         0         0         0
  33            0         1         0         0         0         0
  36            0         0         1         0         0         0
  49            0         0         0         1         0         0
  52            0         0         0         0         1         0
  over:         0         0         0         0         0         0
  count:        1         1         1         1         1         0
  min:          2        33        36        49        52 18446744073709551615
  avg:          2        33        36        49        52         -
  max:          2        33        36        49        52         0
  rtla timerlat hit stop tracing
    IRQ handler delay:		(exit from idle)	    48.21 us (91.09 %)
    IRQ latency:						    49.11 us
    Timerlat IRQ duration:				     2.17 us (4.09 %)
    Blocking thread:					     1.01 us (1.90 %)
  	               swapper/2:0        		     1.01 us
  ------------------------------------------------------------------------
    Thread latency:					    52.93 us (100%)

  Max timerlat IRQ latency from idle: 49.11 us in cpu 2

Note, the value 18446744073709551615 is the same as ~0.

Fix this by reporting no results for the min, avg and max if the count
is 0.

Link: https://lkml.kernel.org/r/20240510190318.44295-1-jkacur@redhat.com

Cc: stable@vger.kernel.org
Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode")
Suggested-by: Daniel Bristot de Oliveria &lt;bristot@kernel.org&gt;
Signed-off-by: John Kacur &lt;jkacur@redhat.com&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 01b05fc0e5f3aec443a9a8ffa0022cbca2fd3608 upstream.

On short runs it is possible to get no samples on a cpu, like this:

  # rtla timerlat hist -u -T50

  Index   IRQ-001   Thr-001   Usr-001   IRQ-002   Thr-002   Usr-002
  2             1         0         0         0         0         0
  33            0         1         0         0         0         0
  36            0         0         1         0         0         0
  49            0         0         0         1         0         0
  52            0         0         0         0         1         0
  over:         0         0         0         0         0         0
  count:        1         1         1         1         1         0
  min:          2        33        36        49        52 18446744073709551615
  avg:          2        33        36        49        52         -
  max:          2        33        36        49        52         0
  rtla timerlat hit stop tracing
    IRQ handler delay:		(exit from idle)	    48.21 us (91.09 %)
    IRQ latency:						    49.11 us
    Timerlat IRQ duration:				     2.17 us (4.09 %)
    Blocking thread:					     1.01 us (1.90 %)
  	               swapper/2:0        		     1.01 us
  ------------------------------------------------------------------------
    Thread latency:					    52.93 us (100%)

  Max timerlat IRQ latency from idle: 49.11 us in cpu 2

Note, the value 18446744073709551615 is the same as ~0.

Fix this by reporting no results for the min, avg and max if the count
is 0.

Link: https://lkml.kernel.org/r/20240510190318.44295-1-jkacur@redhat.com

Cc: stable@vger.kernel.org
Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode")
Suggested-by: Daniel Bristot de Oliveria &lt;bristot@kernel.org&gt;
Signed-off-by: John Kacur &lt;jkacur@redhat.com&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools/rtla: Fix Makefile compiler options for clang</title>
<updated>2024-02-23T08:25:15+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2024-02-06T11:05:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=02afaeb6c52b7948f2992735b10d2fa37d9fc064'/>
<id>02afaeb6c52b7948f2992735b10d2fa37d9fc064</id>
<content type='text'>
commit bc4cbc9d260ba8358ca63662919f4bb223cb603b upstream.

The following errors are showing up when compiling rtla with clang:

 $ make HOSTCC=clang CC=clang LLVM_IAS=1
 [...]

  clang -O -g -DVERSION=\"6.8.0-rc1\" -flto=auto -ffat-lto-objects
	-fexceptions -fstack-protector-strong
	-fasynchronous-unwind-tables -fstack-clash-protection  -Wall
	-Werror=format-security -Wp,-D_FORTIFY_SOURCE=2
	-Wp,-D_GLIBCXX_ASSERTIONS -Wno-maybe-uninitialized
	$(pkg-config --cflags libtracefs)    -c -o src/utils.o src/utils.c

  clang: warning: optimization flag '-ffat-lto-objects' is not supported [-Wignored-optimization-argument]
  warning: unknown warning option '-Wno-maybe-uninitialized'; did you mean '-Wno-uninitialized'? [-Wunknown-warning-option]
  1 warning generated.

  clang -o rtla -ggdb  src/osnoise.o src/osnoise_hist.o src/osnoise_top.o
  src/rtla.o src/timerlat_aa.o src/timerlat.o src/timerlat_hist.o
  src/timerlat_top.o src/timerlat_u.o src/trace.o src/utils.o $(pkg-config --libs libtracefs)

  src/osnoise.o: file not recognized: file format not recognized
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  make: *** [Makefile:110: rtla] Error 1

Solve these issues by:
  - removing -ffat-lto-objects and -Wno-maybe-uninitialized if using clang
  - informing the linker about -flto=auto

Link: https://lore.kernel.org/linux-trace-kernel/567ac1b94effc228ce9a0225b9df7232a9b35b55.1707217097.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Bill Wendling &lt;morbo@google.com&gt;
Cc: Justin Stitt &lt;justinstitt@google.com&gt;
Fixes: 1a7b22ab15eb ("tools/rtla: Build with EXTRA_{C,LD}FLAGS")
Suggested-by: Donald Zickus &lt;dzickus@redhat.com&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit bc4cbc9d260ba8358ca63662919f4bb223cb603b upstream.

The following errors are showing up when compiling rtla with clang:

 $ make HOSTCC=clang CC=clang LLVM_IAS=1
 [...]

  clang -O -g -DVERSION=\"6.8.0-rc1\" -flto=auto -ffat-lto-objects
	-fexceptions -fstack-protector-strong
	-fasynchronous-unwind-tables -fstack-clash-protection  -Wall
	-Werror=format-security -Wp,-D_FORTIFY_SOURCE=2
	-Wp,-D_GLIBCXX_ASSERTIONS -Wno-maybe-uninitialized
	$(pkg-config --cflags libtracefs)    -c -o src/utils.o src/utils.c

  clang: warning: optimization flag '-ffat-lto-objects' is not supported [-Wignored-optimization-argument]
  warning: unknown warning option '-Wno-maybe-uninitialized'; did you mean '-Wno-uninitialized'? [-Wunknown-warning-option]
  1 warning generated.

  clang -o rtla -ggdb  src/osnoise.o src/osnoise_hist.o src/osnoise_top.o
  src/rtla.o src/timerlat_aa.o src/timerlat.o src/timerlat_hist.o
  src/timerlat_top.o src/timerlat_u.o src/trace.o src/utils.o $(pkg-config --libs libtracefs)

  src/osnoise.o: file not recognized: file format not recognized
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  make: *** [Makefile:110: rtla] Error 1

Solve these issues by:
  - removing -ffat-lto-objects and -Wno-maybe-uninitialized if using clang
  - informing the linker about -flto=auto

Link: https://lore.kernel.org/linux-trace-kernel/567ac1b94effc228ce9a0225b9df7232a9b35b55.1707217097.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Bill Wendling &lt;morbo@google.com&gt;
Cc: Justin Stitt &lt;justinstitt@google.com&gt;
Fixes: 1a7b22ab15eb ("tools/rtla: Build with EXTRA_{C,LD}FLAGS")
Suggested-by: Donald Zickus &lt;dzickus@redhat.com&gt;
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools/rtla: Fix uninitialized bucket/data-&gt;bucket_size warning</title>
<updated>2024-02-23T08:25:15+00:00</updated>
<author>
<name>Daniel Bristot de Oliveira</name>
<email>bristot@kernel.org</email>
</author>
<published>2024-02-06T11:05:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f0542eb7122e34d6dae9c19684951d52de34d445'/>
<id>f0542eb7122e34d6dae9c19684951d52de34d445</id>
<content type='text'>
commit 64dc40f7523369912d7adb22c8cb655f71610505 upstream.

When compiling rtla with clang, I am getting the following warnings:

$ make HOSTCC=clang CC=clang LLVM_IAS=1

[..]
clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions
	-fstack-protector-strong -fasynchronous-unwind-tables
	-fstack-clash-protection  -Wall -Werror=format-security
	-Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS
	$(pkg-config --cflags libtracefs)
	-c -o src/osnoise_hist.o src/osnoise_hist.c
src/osnoise_hist.c:138:6: warning: variable 'bucket' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
  138 |         if (data-&gt;bucket_size)
      |             ^~~~~~~~~~~~~~~~~
src/osnoise_hist.c:149:6: note: uninitialized use occurs here
  149 |         if (bucket &lt; entries)
      |             ^~~~~~
src/osnoise_hist.c:138:2: note: remove the 'if' if its condition is always true
  138 |         if (data-&gt;bucket_size)
      |         ^~~~~~~~~~~~~~~~~~~~~~
  139 |                 bucket = duration / data-&gt;bucket_size;
src/osnoise_hist.c:132:12: note: initialize the variable 'bucket' to silence this warning
  132 |         int bucket;
      |                   ^
      |                    = 0
1 warning generated.

[...]

clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions
	-fstack-protector-strong -fasynchronous-unwind-tables
	-fstack-clash-protection  -Wall -Werror=format-security
	-Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS
	$(pkg-config --cflags libtracefs)
	-c -o src/timerlat_hist.o src/timerlat_hist.c
src/timerlat_hist.c:181:6: warning: variable 'bucket' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
  181 |         if (data-&gt;bucket_size)
      |             ^~~~~~~~~~~~~~~~~
src/timerlat_hist.c:204:6: note: uninitialized use occurs here
  204 |         if (bucket &lt; entries)
      |             ^~~~~~
src/timerlat_hist.c:181:2: note: remove the 'if' if its condition is always true
  181 |         if (data-&gt;bucket_size)
      |         ^~~~~~~~~~~~~~~~~~~~~~
  182 |                 bucket = latency / data-&gt;bucket_size;
src/timerlat_hist.c:175:12: note: initialize the variable 'bucket' to silence this warning
  175 |         int bucket;
      |                   ^
      |                    = 0
1 warning generated.

This is a legit warning, but data-&gt;bucket_size is always &gt; 0 (see
timerlat_hist_parse_args()), so the if is not necessary.

Remove the unneeded if (data-&gt;bucket_size) to avoid the warning.

Link: https://lkml.kernel.org/r/6e1b1665cd99042ae705b3e0fc410858c4c42346.1707217097.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Bill Wendling &lt;morbo@google.com&gt;
Cc: Justin Stitt &lt;justinstitt@google.com&gt;
Cc: Donald Zickus &lt;dzickus@redhat.com&gt;
Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode")
Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 64dc40f7523369912d7adb22c8cb655f71610505 upstream.

When compiling rtla with clang, I am getting the following warnings:

$ make HOSTCC=clang CC=clang LLVM_IAS=1

[..]
clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions
	-fstack-protector-strong -fasynchronous-unwind-tables
	-fstack-clash-protection  -Wall -Werror=format-security
	-Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS
	$(pkg-config --cflags libtracefs)
	-c -o src/osnoise_hist.o src/osnoise_hist.c
src/osnoise_hist.c:138:6: warning: variable 'bucket' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
  138 |         if (data-&gt;bucket_size)
      |             ^~~~~~~~~~~~~~~~~
src/osnoise_hist.c:149:6: note: uninitialized use occurs here
  149 |         if (bucket &lt; entries)
      |             ^~~~~~
src/osnoise_hist.c:138:2: note: remove the 'if' if its condition is always true
  138 |         if (data-&gt;bucket_size)
      |         ^~~~~~~~~~~~~~~~~~~~~~
  139 |                 bucket = duration / data-&gt;bucket_size;
src/osnoise_hist.c:132:12: note: initialize the variable 'bucket' to silence this warning
  132 |         int bucket;
      |                   ^
      |                    = 0
1 warning generated.

[...]

clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions
	-fstack-protector-strong -fasynchronous-unwind-tables
	-fstack-clash-protection  -Wall -Werror=format-security
	-Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS
	$(pkg-config --cflags libtracefs)
	-c -o src/timerlat_hist.o src/timerlat_hist.c
src/timerlat_hist.c:181:6: warning: variable 'bucket' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
  181 |         if (data-&gt;bucket_size)
      |             ^~~~~~~~~~~~~~~~~
src/timerlat_hist.c:204:6: note: uninitialized use occurs here
  204 |         if (bucket &lt; entries)
      |             ^~~~~~
src/timerlat_hist.c:181:2: note: remove the 'if' if its condition is always true
  181 |         if (data-&gt;bucket_size)
      |         ^~~~~~~~~~~~~~~~~~~~~~
  182 |                 bucket = latency / data-&gt;bucket_size;
src/timerlat_hist.c:175:12: note: initialize the variable 'bucket' to silence this warning
  175 |         int bucket;
      |                   ^
      |                    = 0
1 warning generated.

This is a legit warning, but data-&gt;bucket_size is always &gt; 0 (see
timerlat_hist_parse_args()), so the if is not necessary.

Remove the unneeded if (data-&gt;bucket_size) to avoid the warning.

Link: https://lkml.kernel.org/r/6e1b1665cd99042ae705b3e0fc410858c4c42346.1707217097.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Bill Wendling &lt;morbo@google.com&gt;
Cc: Justin Stitt &lt;justinstitt@google.com&gt;
Cc: Donald Zickus &lt;dzickus@redhat.com&gt;
Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode")
Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode")
Signed-off-by: Daniel Bristot de Oliveira &lt;bristot@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
