linux.git/tools/tracing/rtla/src, branch v6.12.80

rtla/timerlat_top: Abort event processing on second signal

2025-02-21T13:01:25+00:00

[ Upstream commit 80967b354a76b360943af384c10d807d98bea5c4 ]

If either SIGINT is received twice, or after a SIGALRM (that is, after
timerlat was supposed to stop), abort processing events currently left
in the tracefs buffer and exit immediately.

This allows the user to exit rtla without waiting for processing all
events, should that take longer than wanted, at the cost of not
processing all samples.

Cc: John Kacur 
Cc: Luis Goncalves 
Cc: Gabriele Monaco 
Link: https://lore.kernel.org/20250116144931.649593-6-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Sasha Levin

rtla/timerlat_hist: Abort event processing on second signal

2025-02-21T13:01:25+00:00

[ Upstream commit d6899e560366e10141189697502bc5521940c588 ]

If either SIGINT is received twice, or after a SIGALRM (that is, after
timerlat was supposed to stop), abort processing events currently left
in the tracefs buffer and exit immediately.

This allows the user to exit rtla without waiting for processing all
events, should that take longer than wanted, at the cost of not
processing all samples.

Cc: John Kacur 
Cc: Luis Goncalves 
Cc: Gabriele Monaco 
Link: https://lore.kernel.org/20250116144931.649593-5-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Sasha Levin

rtla/timerlat_top: Stop timerlat tracer on signal

2025-02-17T09:05:43+00:00

commit a4dfce7559d75430c464294ddee554be2a413c4a upstream.

Currently, when either SIGINT from the user or SIGALRM from the duration
timer is caught by rtla-timerlat, stop_tracing is set to break out of
the main loop. This is not sufficient for cases where the timerlat
tracer is producing more data than rtla can consume, since in that case,
rtla is looping indefinitely inside tracefs_iterate_raw_events, never
reaches the check of stop_tracing and hangs.

In addition to setting stop_tracing, also stop the timerlat tracer on
received signal (SIGINT or SIGALRM). This will stop new samples so that
the existing samples may be processed and tracefs_iterate_raw_events
eventually exits.

Cc: stable@vger.kernel.org
Cc: John Kacur 
Cc: Luis Goncalves 
Cc: Gabriele Monaco 
Link: https://lore.kernel.org/20250116144931.649593-4-tglozar@redhat.com
Fixes: a828cd18bc4a ("rtla: Add timerlat tool and timelart top mode")
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

rtla/timerlat_hist: Stop timerlat tracer on signal

2025-02-17T09:05:43+00:00

commit c73cab9dbed04d8f65ca69177b4b21ed3e09dfa7 upstream.

Currently, when either SIGINT from the user or SIGALRM from the duration
timer is caught by rtla-timerlat, stop_tracing is set to break out of
the main loop. This is not sufficient for cases where the timerlat
tracer is producing more data than rtla can consume, since in that case,
rtla is looping indefinitely inside tracefs_iterate_raw_events, never
reaches the check of stop_tracing and hangs.

In addition to setting stop_tracing, also stop the timerlat tracer on
received signal (SIGINT or SIGALRM). This will stop new samples so that
the existing samples may be processed and tracefs_iterate_raw_events
eventually exits.

Cc: stable@vger.kernel.org
Cc: John Kacur 
Cc: Luis Goncalves 
Cc: Gabriele Monaco 
Link: https://lore.kernel.org/20250116144931.649593-3-tglozar@redhat.com
Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode")
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

rtla: Add trace_instance_stop

2025-02-17T09:05:43+00:00

commit e879b5dcf8d044f3865a32d95cc5b213f314c54f upstream.

Support not only turning trace on for the timerlat tracer, but also
turning it off.

This will be used in subsequent patches to stop the timerlat tracer
without also wiping the trace buffer.

Cc: stable@vger.kernel.org
Cc: John Kacur 
Cc: Luis Goncalves 
Cc: Gabriele Monaco 
Link: https://lore.kernel.org/20250116144931.649593-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

rtla/timerlat_top: Set OSNOISE_WORKLOAD for kernel threads

2025-02-17T09:05:43+00:00

commit 217f0b1e990e30a1f06f6d531fdb4530f4788d48 upstream.

When using rtla timerlat with userspace threads (-u or -U), rtla
disables the OSNOISE_WORKLOAD option in
/sys/kernel/tracing/osnoise/options. This option is not re-enabled in a
subsequent run with kernel-space threads, leading to rtla collecting no
results if the previous run exited abnormally:

$ rtla timerlat top -u
^\Quit (core dumped)
$ rtla timerlat top -k -d 1s
                                     Timer Latency
  0 00:00:01   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max

The issue persists until OSNOISE_WORKLOAD is set manually by running:
$ echo OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options

Set OSNOISE_WORKLOAD when running rtla with kernel-space threads if
available to fix the issue.

Cc: stable@vger.kernel.org
Cc: John Kacur 
Cc: Luis Goncalves 
Link: https://lore.kernel.org/20250107144823.239782-4-tglozar@redhat.com
Fixes: cdca4f4e5e8e ("rtla/timerlat_top: Add timerlat user-space support")
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

rtla/timerlat_hist: Set OSNOISE_WORKLOAD for kernel threads

2025-02-17T09:05:42+00:00

commit d8d866171a414ed88bd0d720864095fd75461134 upstream.

When using rtla timerlat with userspace threads (-u or -U), rtla
disables the OSNOISE_WORKLOAD option in
/sys/kernel/tracing/osnoise/options. This option is not re-enabled in a
subsequent run with kernel-space threads, leading to rtla collecting no
results if the previous run exited abnormally:

$ rtla timerlat hist -u
^\Quit (core dumped)
$ rtla timerlat hist -k -d 1s
Index
over:
count:
min:
avg:
max:
ALL:        IRQ       Thr       Usr
count:        0         0         0
min:          -         -         -
avg:          -         -         -
max:          -         -         -

The issue persists until OSNOISE_WORKLOAD is set manually by running:
$ echo OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options

Set OSNOISE_WORKLOAD when running rtla with kernel-space threads if
available to fix the issue.

Cc: stable@vger.kernel.org
Cc: John Kacur 
Cc: Luis Goncalves 
Link: https://lore.kernel.org/20250107144823.239782-3-tglozar@redhat.com
Fixes: ed774f7481fa ("rtla/timerlat_hist: Add timerlat user-space support")
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

rtla/osnoise: Distinguish missing workload option

2025-02-17T09:05:42+00:00

commit 80d3ba1cf51bfbbb3b098434f2b2c95cd7c0ae5c upstream.

osnoise_set_workload returns -1 for both missing OSNOISE_WORKLOAD option
and failure in setting the option.

Return -1 for missing and -2 for failure to distinguish them.

Cc: stable@vger.kernel.org
Cc: John Kacur 
Cc: Luis Goncalves 
Link: https://lore.kernel.org/20250107144823.239782-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

rtla/timerlat: Fix histogram ALL for zero samples

2025-01-02T09:34:22+00:00

commit 6cc45f8c1f898570916044f606be9890d295e129 upstream.

rtla timerlat hist currently computers the minimum, maximum and average
latency even in cases when there are zero samples. This leads to
nonsensical values being calculated for maximum and minimum, and to
divide by zero for average.

A similar bug is fixed by 01b05fc0e5f3 ("rtla/timerlat: Fix histogram
report when a cpu count is 0") but the bug still remains for printing
the sum over all CPUs in timerlat_print_stats_all.

The issue can be reproduced with this command:

$ rtla timerlat hist -U -d 1s
Index
over:
count:
min:
avg:
max:
Floating point exception (core dumped)

(There are always no samples with -U unless the user workload is
created.)

Fix the bug by omitting max/min/avg when sample count is zero,
displaying a dash instead, just like we already do for the individual
CPUs. The logic is moved into a new function called
format_summary_value, which is used for both the individual CPUs
and for the overall summary.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20241127134130.51171-1-tglozar@redhat.com
Fixes: 1462501c7a8 ("rtla/timerlat: Add a summary for hist mode")
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

rtla/timerlat: Make timerlat_hist_cpu->*_count unsigned long long

2024-12-14T19:03:59+00:00

[ Upstream commit 76b3102148135945b013797fac9b206273f0f777 ]

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 
Signed-off-by: Tomas Glozar 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Sasha Levin