Implement actions on end next to actions on threshold. A new option,
--on-end is added, parallel to --on-threshold. Instead of being
executed whenever a latency threshold is reached, it is executed at the
end of the measurement.
For example:
$ rtla timerlat hist -d 5s --on-end trace
will save the trace output at the end.
All actions supported by --on-threshold are also supported by --on-end,
except for continue, which does nothing with --on-end.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Chang Yin <cyin@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Cc: Crystal Wood <crwood@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250626123405.1496931-6-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Introduce option to resume tracing after a latency threshold overflow.
The option is implemented as an action named "continue".
Example:
$ rtla timerlat top -q -T 200 -d 1s --on-threshold \
exec,command="echo Threshold" --on-threshold continue
Threshold
Threshold
Threshold
Timer Latency
...
The feature is supported for both hist and top. After the continue
action is executed, processing of the list of actions is stopped and
tracing is resumed.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Chang Yin <cyin@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Cc: Crystal Wood <crwood@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250626123405.1496931-5-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently, rtla-timerlat BPF program uses a global variable stored in a
.bss section to store whether tracing has been stopped.
Move the information to a separate map, so that it is easily writable
from userspace, and add a function that clears the value, resuming
tracing after it has been stopped.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Chang Yin <cyin@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Cc: Crystal Wood <crwood@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250626123405.1496931-4-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Extend the functionality provided by the -t/--trace option, which
triggers saving the contents of a tracefs buffer after tracing is
stopped, to support implementing arbitrary actions.
A new option, --on-threshold, is added, taking an argument
that further specifies the action. Actions added in this patch are:
- trace[,file=<filename>]: Saves tracefs buffer, optionally taking a
filename.
- signal,num=<sig>,pid=<pid>: Sends signal to process. "parent" might
be specified instead of number to send signal to parent process.
- shell,command=<command>: Execute shell command.
Multiple actions may be specified and will be executed in order,
including multiple actions of the same type. Trace output requested via
-t and -a now adds a trace action to the end of the list.
If an action fails, the following actions are not executed. For
example, this command:
$ rtla timerlat -T 20 --on-threshold trace \
--on-threshold shell,command="grep ipi_send timerlat_trace.txt" \
--on-threshold signal,num=2,pid=parent
will send signal 2 (SIGINT) to parent process, but only if saved trace
contains the text "ipi_send".
This way, the feature can be used for flexible reactions on latency
spikes, and allows combining rtla with other tooling like perf.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Chang Yin <cyin@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Cc: Crystal Wood <crwood@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250626123405.1496931-3-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
After the introduction of BPF-based sample collection, rtla-timerlat
effectively runs in one of three modes:
- Pure BPF mode, with tracefs only being used to set up the timerlat
tracer. Sample processing and stop on threshold are handled by BPF.
- tracefs mode. BPF is unsupported or kernel is lacking the necessary
trace event (osnoise:timerlat_sample). Stop on theshold is handled by
timerlat tracer stopping tracing in all instances.
- BPF/tracefs mixed mode - BPF is used for sample collection for top or
histogram, tracefs is used for trace output and/or auto-analysis. Stop
on threshold is handled both through BPF program, which stops sample
collection for top/histogram and wakes up rtla, and by timerlat
tracer, which stops tracing for trace output/auto-analysis instances.
Add enum timerlat_tracing_mode, with three values:
- TRACING_MODE_BPF
- TRACING_MODE_TRACEFS
- TRACING_MODE_MIXED
Those represent the modes described above. A field of this type is added
to struct timerlat_params, named "mode", replacing the no_bpf variable.
params->mode is set in timerlat_{top,hist}_parse_args to
TRACING_MODE_BPF or TRACING_MODE_MIXED based on whether trace output
and/or auto-analysis is requested. timerlat_{top,hist}_main then checks
if BPF is not unavailable or disabled, in that case, it sets
params->mode to TRACING_MODE_TRACEFS.
A condition is added to timerlat_apply_config that skips setting
timerlat tracer thresholds if params->mode is TRACING_MODE_BPF (those
are unnecessary, since they only turn off tracing, which is already
turned off in that case, since BPF is used to collect samples).
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Chang Yin <cyin@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Cc: Crystal Wood <crwood@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250626123405.1496931-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Newer versions of glibc include a definition of struct sched_attr in
bits/sched.h (included through sched.h which is included by rtla).
Commit 0eecee3406 ("tools/rtla: fix collision with glibc
sched_attr/sched_set_attr") has modified the definition of struct
sched_attr in utils.h, so that it is only applied with older versions of
glibc that do not define it, in order to prevent build failure.
The definition in bits/sched.h depends on _GNU_SOURCE.
timerlat_bpf.c does not define _GNU_SOURCE, making it fall back to the
definition in utils.h. The latter has two fields less, leading to
shifted offsets of struct timerlat_params in timerlat_bpf_init.
Because of the shift, timerlat_bpf_init incorrectly reads
params->entries as 0 for timerlat-hist and disables the creation of
histogram maps, causing breakage in BPF sample collection mode:
$ rtla timerlat hist -d 1s
Error pulling BPF data
Fix the issue by also defining _GNU_SOURCE in timerlat_bpf.c.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250430144651.621766-1-tglozar@redhat.com
Fixes: e34293ddce ("rtla/timerlat: Add BPF skeleton to collect samples")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When executing "make -C tools/tracing/rtla" on LoongArch, there exists
the following error:
src/utils.c:237:24: error: '__NR_sched_setattr' undeclared
Just define __NR_sched_setattr for LoongArch if not exist.
Link: https://lore.kernel.org/20250422074917.25771-1-yangtiezhu@loongson.cn
Reported-by: Haiyong Sun <sunhaiyong@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
A test is considered failed when a sample trace exceeds the threshold.
Failed tests return the same exit code as passed tests, requiring test
frameworks to determine the result by searching for "hit stop tracing"
in the output.
Assign a distinct exit code for failed tests to enable the use of shell
expressions and seamless integration with testing frameworks without the
need to parse output.
Add enum type for return value.
Update `make check`.
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Eder Zulian <ezulian@redhat.com>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Jan Stancek <jstancek@redhat.com>
Link: https://lore.kernel.org/20250417185757.2194541-1-costa.shul@redhat.com
Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
Reviewed-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
rtla currently only sets tracer options that are explicitly set by the
user, with the exception of OSNOISE_WORKLOAD.
This leads to improper behavior in case rtla is run with those options
not set to the default value. rtla does reset them to the original
value upon exiting, but that does not protect it from starting with
non-default values set either by an improperly exited rtla or by another
user of the tracers.
For example, after running this command:
$ echo 1 > /sys/kernel/tracing/osnoise/stop_tracing_us
all runs of rtla will stop at the 1us threshold, even if not requested
by the user:
$ rtla osnoise hist
Index CPU-000 CPU-001
1 8 5
2 5 9
3 1 2
4 6 1
5 2 1
6 0 1
8 1 1
12 0 1
14 1 0
15 1 0
over: 0 0
count: 25 21
min: 1 1
avg: 3.68 3.05
max: 15 12
rtla osnoise hit stop tracing
Fix the problem by setting the default value for all tracer options if
the user has not provided their own value.
For most of the options, it's enough to just drop the if clause checking
for the value being set. For cpus, "all" is used as the default value,
and for osnoise default period and runtime, default values of
the osnoise_data variable in trace_osnoise.c are used.
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250320092500.101385-5-tglozar@redhat.com
Fixes: 1eceb2fc2c ("rtla/osnoise: Add osnoise top mode")
Fixes: 829a6c0b56 ("rtla/osnoise: Add the hist mode")
Fixes: a828cd18bc ("rtla: Add timerlat tool and timelart top mode")
Fixes: 1eeb6328e8 ("rtla/timerlat: Add timerlat hist mode")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Reviewed-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If running rtla osnoise with NO_OSNOISE_WORKLOAD, it reports no samples:
$ echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options
$ rtla osnoise hist -d 10s
Index
over: 0
count: 0
min: 0
avg: 0
max: 0
This situation can also happen when running rtla-osnoise after an
improperly exited rtla-timerlat run.
Set OSNOISE_WORKLOAD in rtla-osnoise, too, similarly to what we
already did for timerlat in commit 217f0b1e99 ("rtla/timerlat_top: Set
OSNOISE_WORKLOAD for kernel threads") and commit d8d866171a
("rtla/timerlat_hist: Set OSNOISE_WORKLOAD for kernel threads").
Note that there is no user workload mode for rtla-osnoise yet, so
OSNOISE_WORKLOAD is always set to true.
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250320092500.101385-4-tglozar@redhat.com
Fixes: 1eceb2fc2c ("rtla/osnoise: Add osnoise top mode")
Fixes: 829a6c0b56 ("rtla/osnoise: Add the hist mode")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Reviewed-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The functions osnoise_top_apply_config and osnoise_hist_apply_config, as
well as timerlat_top_apply_config and timerlat_hist_apply_config, are
mostly the same.
Move common part from them into separate functions osnoise_apply_config
and timerlat_apply_config.
For rtla-timerlat, also unify params->user_hist and params->user_top
into one field called params->user_data, and move several fields used
only by timerlat-top into the top-only section of struct
timerlat_params.
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250320092500.101385-3-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Reviewed-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Instead of having separate structs osnoise_top_params and
osnoise_hist_params, use one struct osnoise_params for both.
This allows code using the structs to be shared between osnoise-top and
osnoise-hist.
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250320092500.101385-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Reviewed-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Running rtla with exit on threshold, but without saving trace leads to a
segmenetation fault:
$ rtla timerlat hist -T 10
...
Max timerlat IRQ latency from idle: 4.29 us in cpu 0
Segmentation fault
This is caused by null pointer deference in the call of
save_trace_to_file, which attempts to dereference an uninitialized
osnoise_tool variable:
save_trace_to_file(record->trace.inst, params->trace_output);
^ this is uninitialized if params->trace_output is
not set
Fix this by not attempting to dereference "record" if it is NULL and
passing NULL instead. As a safety measure, the first field is also
checked for NULL inside save_trace_to_file.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Link: https://lore.kernel.org/20250313141034.299117-1-tglozar@redhat.com
Fixes: dc4d4e7c72 ("rtla: Refactor save_trace_to_file")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The functions osnoise_hist_main(), osnoise_top_main(),
timerlat_hist_main(), and timerlat_top_main() are lengthy and contain
duplicated code.
Refactor by consolidating the duplicate lines into the
save_trace_to_file() function.
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Eder Zulian <ezulian@redhat.com>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250219115138.406075-1-costa.shul@redhat.com
Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
Reviewed-by: Tomas Glozar <tglozar@redhat.com>
Tested-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Collect samples using BPF program instead of pulling them from tracefs.
If the osnoise:timerlat_sample tracepoint is unavailable or the BPF
program fails to load for whatever reason, rtla falls back to the old
implementation.
The collection of samples using the BPF program is fully self-contained
and requires no activity of the userspace part of rtla during the
measurement. Thus, rtla only pulls the summary from the BPF map and
displays it every second, improving the performance.
In --aa-only mode, the BPF program does not collect any data and only
signalizes the end of tracing to userspace. An optimization that re-used
the main trace instance for auto-analysis in aa-only mode was dropped, as
rtla no longer turns tracing on in the main trace instance, making it
useless for auto-analysis.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250218145859.27762-8-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Unlike timerlat-hist, timerlat-top applies the output divisor used to
set ns/us mode when printing results instead of applying it when
collecting the samples.
Move the application of the divisor from timerlat_top_print into
timerlat_top_update to make it consistent with timerlat-hist.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250218145859.27762-7-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Collect samples using BPF program instead of pulling them from tracefs.
If the osnoise:timerlat_sample tracepoint is unavailable or the BPF
program fails to load for whatever reason, rtla falls back to the old
implementation.
The collection of samples using the BPF program is fully self-contained
and requires no activity of the userspace part of rtla during the
measurement. Thus, instead of waking up every second to collect samples,
rtla simply sleeps until woken up by a signal or threshold overflow.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250218145859.27762-6-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add BPF program that attaches to the osnoise:timerlat_sample tracepoint
and collects both the summary and the histogram (if requested) into BPF
maps (one map of each kind per context).
The program is designed to be used for both timerlat-top and
timerlat-hist. If using with timerlat-top, the "entries" parameter is
set to zero, which prevents the BPF program from recording histogram
entries. In that case, the maps for histograms do not have to be
created, as the BPF verifier will identify the code using them as
unreachable.
An IRQ or thread latency threshold might be supplied to stop recording
if hit, similar to the timerlat tracer threshold, which stops ftrace
tracing if hit. A BPF ringbuffer is used to signal threshold overflow to
userspace. In aa-only mode, this is the only function of the BPF
program.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250218145859.27762-5-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Instead of having separate structs timerlat_top_params and
timerlat_hist_params, use one struct timerlat_params for both.
This allows code using the structs to be shared between timerlat-top and
timerlat-hist.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250218145859.27762-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Add a test suite to test the tool
Add a small test suite that can be used to test rtla's basic features to
at least have something to test when applying changes.
- Automate manual steps in monitor creation
While creating a new monitor in RV, besides generating code from dot2k,
there are a few manual steps which can be tedious and error prone, like
adding the tracepoints, makefile lines and kconfig, or selecting events
that start the monitor in the initial state.
Updates were made to try and automate as much as possible among those steps to
make creating a new RV monitor much quicker. It is still requires to
select proper tracepoints, this step is harder to automate in a general
way and, in several cases, would still need user intervention.
- Have rtla timerlat hist and top set OSNOISE_WORKLOAD flag
Have both rtla-timerlat-hist and rtla-timerlat-top set OSNOISE_WORKLOAD to
the proper value ("on" when running with -k, "off" when running with -u)
every time the option is available instead of setting it only when running
with -u.
This prevents rtla timerlat -k from giving no results when
NO_OSNOISE_WORKLOAD is set, either manually or by an abnormally exited earlier
run of rtla timerlat -u.
- Stop rtla timerlat on signal properly when overloaded
There is an issue where if rtla is run on machines with a high number of
CPUs (100+), timerlat can generate more samples than rtla is able to process
via tracefs_iterate_raw_events. This is especially common when the interval
is set to 100us (rteval and cyclictest default) as opposed to the rtla
default of 1000us, but also happens with the rtla default.
Currently, this leads to rtla hanging and having to be terminated with
SIGTERM. SIGINT setting stop_tracing is not enough, since more and more
events are coming and tracefs_iterate_raw_events never exits.
To fix this: Stop the timerlat tracer on SIGINT/SIGALRM to ensure no more
events are generated when rtla is supposed to exit.
Also on receiving SIGINT/SIGALRM twice, abort iteration immediately with
tracefs_iterate_stop, making rtla exit right away instead of waiting for all
events to be processed.
- Account for missed events
Due to tracefs buffer overflow, it can happen that rtla misses events,
making the tracing results inaccurate.
Count both the number of missed events and the total number of processed
events, and display missed events as well as their percentage. The numbers
are displayed for both osnoise and timerlat, even though for the earlier,
missed events are generally not expected.
For hist, the number is displayed at the end of the run; for top, it is
displayed on each printing of the top table.
- Changes to make osnoise more robust
There was a dependency in the code that the first field of the
osnoise_tool structure was the trace field. If that that ever changed,
then the code work break. Change the code to encapsulate this dependency
where the code that uses the structure does not have this dependency.
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Merge tag 'trace-tools-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull rv and tools/rtla updates from Steven Rostedt:
- Add a test suite to test the tool
Add a small test suite that can be used to test rtla's basic features
to at least have something to test when applying changes.
- Automate manual steps in monitor creation
While creating a new monitor in RV, besides generating code from
dot2k, there are a few manual steps which can be tedious and error
prone, like adding the tracepoints, makefile lines and kconfig, or
selecting events that start the monitor in the initial state.
Updates were made to try and automate as much as possible among those
steps to make creating a new RV monitor much quicker. It is still
requires to select proper tracepoints, this step is harder to
automate in a general way and, in several cases, would still need
user intervention.
- Have rtla timerlat hist and top set OSNOISE_WORKLOAD flag
Have both rtla-timerlat-hist and rtla-timerlat-top set
OSNOISE_WORKLOAD to the proper value ("on" when running with -k,
"off" when running with -u) every time the option is available
instead of setting it only when running with -u.
This prevents rtla timerlat -k from giving no results when
NO_OSNOISE_WORKLOAD is set, either manually or by an abnormally
exited earlier run of rtla timerlat -u.
- Stop rtla timerlat on signal properly when overloaded
There is an issue where if rtla is run on machines with a high number
of CPUs (100+), timerlat can generate more samples than rtla is able
to process via tracefs_iterate_raw_events. This is especially common
when the interval is set to 100us (rteval and cyclictest default) as
opposed to the rtla default of 1000us, but also happens with the rtla
default.
Currently, this leads to rtla hanging and having to be terminated
with SIGTERM. SIGINT setting stop_tracing is not enough, since more
and more events are coming and tracefs_iterate_raw_events never
exits.
To fix this: Stop the timerlat tracer on SIGINT/SIGALRM to ensure no
more events are generated when rtla is supposed to exit.
Also on receiving SIGINT/SIGALRM twice, abort iteration immediately
with tracefs_iterate_stop, making rtla exit right away instead of
waiting for all events to be processed.
- Account for missed events
Due to tracefs buffer overflow, it can happen that rtla misses
events, making the tracing results inaccurate.
Count both the number of missed events and the total number of
processed events, and display missed events as well as their
percentage. The numbers are displayed for both osnoise and timerlat,
even though for the earlier, missed events are generally not
expected.
For hist, the number is displayed at the end of the run; for top, it
is displayed on each printing of the top table.
- Changes to make osnoise more robust
There was a dependency in the code that the first field of the
osnoise_tool structure was the trace field. If that that ever
changed, then the code work break. Change the code to encapsulate
this dependency where the code that uses the structure does not have
this dependency.
* tag 'trace-tools-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (22 commits)
rtla: Report missed event count
rtla: Add function to report missed events
rtla: Count all processed events
rtla: Count missed trace events
tools/rtla: Add osnoise_trace_is_off()
rtla/timerlat_top: Set OSNOISE_WORKLOAD for kernel threads
rtla/timerlat_hist: Set OSNOISE_WORKLOAD for kernel threads
rtla/osnoise: Distinguish missing workload option
rtla/timerlat_top: Abort event processing on second signal
rtla/timerlat_hist: Abort event processing on second signal
rtla/timerlat_top: Stop timerlat tracer on signal
rtla/timerlat_hist: Stop timerlat tracer on signal
rtla: Add trace_instance_stop
tools/rtla: Add basic test suite
verification/dot2k: Implement event type detection
verification/dot2k: Auto patch current kernel source
verification/dot2k: Simplify manual steps in monitor creation
rv: Simplify manual steps in monitor creation
verification/dot2k: Add support for name and description options
verification/dot2k: More robust template variables
...
Print how many events were missed by trace buffer overflow in the main
instance at the end of the run (for hist) or during the run (for top).
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250123142339.990300-5-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Tested-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add osnoise_report_missed_events to be used to report the number
of missed events either during or after an osnoise or timerlat run.
Also, display the percentage of missed events compared to the total
number of received events.
If an unknown number of missed events was reported during the run, the
entire number of missed events is reported as unknown.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250123142339.990300-4-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a field processed_events to struct trace_instance and increment it
in collect_registered_events, regardless of whether a handler is
registered for the event.
The purpose is to calculate the percentage of events that were missed
due to tracefs buffer overflow.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250123142339.990300-3-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add function collect_missed_events to trace.c to act as a callback for
tracefs_follow_missed_events, summing the number of total missed events
into a new field missing_events of struct trace_instance.
In case record->missed_events is negative, trace->missed_events is set
to UINT64_MAX to signify an unknown number of events was missed.
The callback is activated on initialization of the trace instance.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250123142339.990300-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
All of the users of trace_is_off() passes in &record->trace as the second
parameter, where record is a pointer to a struct osnoise_tool. This record
could be NULL and there is a hidden dependency that the trace field is the
first field to allow &record->trace to work with a NULL record pointer.
In order to make this code a bit more robust, as record shouldn't be
dereferenced if it is NULL, even if the code does work, create a new
function called osnoise_trace_is_off() that takes the pointer to a
struct osnoise_tool as its second parameter. This way it can properly test
if it is NULL before it dereferences it.
The old function trace_is_off() is removed and the function
osnoise_trace_is_off() is added into osnoise.c which is what the
struct osnoise_tool is associated with.
Cc: John Kacur <jkacur@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Eder Zulian <ezulian@redhat.com>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250115180055.2136815-1-costa.shul@redhat.com
Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250107144823.239782-4-tglozar@redhat.com
Fixes: cdca4f4e5e ("rtla/timerlat_top: Add timerlat user-space support")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250107144823.239782-3-tglozar@redhat.com
Fixes: ed774f7481 ("rtla/timerlat_hist: Add timerlat user-space support")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250107144823.239782-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250116144931.649593-6-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250116144931.649593-5-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250116144931.649593-4-tglozar@redhat.com
Fixes: a828cd18bc ("rtla: Add timerlat tool and timelart top mode")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250116144931.649593-3-tglozar@redhat.com
Fixes: 1eeb6328e8 ("rtla/timerlat: Add timerlat hist mode")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250116144931.649593-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 01b05fc0e5 ("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: 1462501c7a ("rtla/timerlat: Add a summary for hist mode")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Add ':' to getopt option 'trace-buffer-size' in timerlat_hist for
consistency
- Remove unused sched_getattr define
- Rename sched_setattr() helper to syscall_sched_setattr() to avoid
conflicts
- Update counters to long from int to avoid overflow
- Add libcpupower dependency detection
- Add --deepest-idle-state to timerlat to limit deep idle sleeps
- Other minor clean ups and documentation changes
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Merge tag 'trace-tools-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing tools updates from Steven Rostedt:
- Add ':' to getopt option 'trace-buffer-size' in timerlat_hist for
consistency
- Remove unused sched_getattr define
- Rename sched_setattr() helper to syscall_sched_setattr() to avoid
conflicts
- Update counters to long from int to avoid overflow
- Add libcpupower dependency detection
- Add --deepest-idle-state to timerlat to limit deep idle sleeps
- Other minor clean ups and documentation changes
* tag 'trace-tools-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
verification/dot2: Improve dot parser robustness
tools/rtla: Improve exception handling in timerlat_load.py
tools/rtla: Enhance argument parsing in timerlat_load.py
tools/rtla: Improve code readability in timerlat_load.py
rtla/timerlat: Do not set params->user_workload with -U
rtla: Documentation: Mention --deepest-idle-state
rtla/timerlat: Add --deepest-idle-state for hist
rtla/timerlat: Add --deepest-idle-state for top
rtla/utils: Add idle state disabling via libcpupower
rtla: Add optional dependency on libcpupower
tools/build: Add libcpupower dependency detection
rtla/timerlat: Make timerlat_hist_cpu->*_count unsigned long long
rtla/timerlat: Make timerlat_top_cpu->*_count unsigned long long
tools/rtla: fix collision with glibc sched_attr/sched_set_attr
tools/rtla: drop __NR_sched_getattr
rtla: Fix consistency in getopt_long for timerlat_hist
rv: Fix a typo
tools/rv: Correct the grammatical errors in the comments
tools/rv: Correct the grammatical errors in the comments
rtla: use the definition for stdout fd when calling isatty()
Since commit fb9e90a67e ("rtla/timerlat: Make user-space threads
the default"), rtla-timerlat has been defaulting to
params->user_workload if neither that or params->kernel_workload is set.
This has unintentionally made -U, which sets only params->user_hist/top
but not params->user_workload, to behave like -u unless -k is set,
preventing the user from running a custom workload.
Example:
$ rtla timerlat hist -U -c 0 &
[1] 7413
$ python sample/timerlat_load.py 0
Error opening timerlat fd, did you run timerlat -U?
$ ps | grep timerlatu
7415 pts/4 00:00:00 timerlatu/0
Fix the issue by checking for params->user_top/hist instead of
params->user_workload when setting default thread mode.
Link: https://lore.kernel.org/20241021123140.14652-1-tglozar@redhat.com
Fixes: fb9e90a67e ("rtla/timerlat: Make user-space threads the default")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add option to limit deepest idle state on CPUs where timerlat is running
for the duration of the workload.
Link: https://lore.kernel.org/20241017140914.3200454-5-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add functions to utils.c to disable idle states through functions of
libcpupower. This will serve as the basis for disabling idle states
per cpu when running timerlat.
Link: https://lore.kernel.org/20241017140914.3200454-4-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <afazekas@redhat.com>
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <afazekas@redhat.com>
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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 <jstancek@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Commit e9a4062e15 ("rtla: Add --trace-buffer-size option") adds a new
long option to rtla utilities, but among all affected files,
timerlat_hist misses a trailing `:` in the corresponding short option
inside the getopt string (e.g. `\3:`). This patch propagates the `:`.
Although this change is not functionally required, it improves
consistency and slightly reduces the likelihood a future change would
introduce a problem.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Link: https://lore.kernel.org/20240926143417.54039-1-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Use the STDOUT_FILENO definition when testing whether the standard
output file descriptor refers to a terminal (for better redability).
Link: https://lore.kernel.org/20240813142338.376039-1-ezulian@redhat.com
Signed-off-by: Eder Zulian <ezulian@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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: 1eceb2fc2c ("rtla/osnoise: Add osnoise top mode")
Fixes: a828cd18bc ("rtla: Add timerlat tool and timelart top mode")
Link: https://lore.kernel.org/20240813155831.384446-1-ezulian@redhat.com
Suggested-by: Tomas Glozar <tglozar@redhat.com>
Reviewed-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Eder Zulian <ezulian@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If the "tool->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 <jkacur@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Fixes: 1eceb2fc2c ("rtla/osnoise: Add osnoise top mode")
Link: https://lore.kernel.org/f964ed1f-64d2-4fde-ad3e-708331f8f358@stanley.mountain
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When osnoise hist does not observe any samples above the threshold,
no entries are recorded and the final report shows empty entries
for the usual statistics (count, min, max, avg):
[~]# osnoise hist -d 5s -T 500
# RTLA osnoise histogram
# Time unit is microseconds (us)
# Duration: 0 00:00:05
Index
over:
count:
min:
avg:
max:
That could lead users to confusing interpretations of the results.
A simple solution is to report 0 for count and the statistics, making it
clear that no noise (above the defined threshold) was observed:
[~]# osnoise hist -d 5s -T 500
# RTLA osnoise histogram
# Time unit is microseconds (us)
# Duration: 0 00:00:05
Index
over: 0
count: 0
min: 0
avg: 0
max: 0
Link: https://lkml.kernel.org/r/Zml6JmH5cbS7-HfZ@uudg.org
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Reviewed-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
osnoise top performs background/font color formatting that could make
the text output confusing if not on a terminal. Use the changes from
commit f5c0cdad66 ("rtla/timerlat: Use pretty formatting only on
interactive tty") as an inspiration to fix this problem.
Apply the formatting only if running on a tty, and not in quiet mode.
Link: https://lkml.kernel.org/r/Zmb-yP_3EDHliI8Z@uudg.org
Suggested-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Reviewed-by: John Kacur <jkacur@redhat.com>
Reviewed-by: Clark Williams <williams@redhat.com>
Signed-off-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
The -t option has an optional argument.
The usual case is for a short option to be specified without an '='
and for the long version to be specified with an '='
Various forms of this do not work as expected.
For example:
rtla timerlat hist -T50 -tfile.txt
will result in a truncated file name of "ile.txt"
Another example is that the long form without the '=' will result in the
default file name instead of the requested file name.
This patch properly parses the optional argument with and without '='
and with and without spaces for the short form.
This patch was also tested using -t and --trace without providing a file
name both as the last requested option and with a following long and
short option.
For example:
rtla timerlat hist -T50 -t -u
rtla timerlat hist -T50 --trace -u
This fix is applied to both timerlat top and hist
and to osnoise top and hist.
Here is the full testing for rtla timerlat hist.
Before applying the patch
rtla timerlat hist -T50 -t=file.txt
Works as expected, "file.txt"
rtla timerlat hist -T50 -tfile.txt
Truncated file name "ile.txt"
rtla timerlat hist -T50 -t file.txt
Default file name instead of file.txt
rtla timerlat hist -T50 --trace=file.txt
Truncated file name "ile.txt"
rtla timerlat hist -T50 --trace file.txt
Default file name "timerlat_trace.txt" instead of "file.txt"
After applying the patch:
rtla timerlat hist -T50 -t=file.txt
Works as expected, "file.txt"
rtla timerlat hist -T50 -tfile.txt
Works as expected, "file.txt"
rtla timerlat hist -T50 -t file.txt
Works as expected, "file.txt"
rtla timerlat hist -T50 --trace=file.txt
Works as expected, "file.txt"
rtla timerlat hist -T50 --trace file.txt
Works as expected, "file.txt"
In addition the following tests were performed to make sure that
the default file name worked as expected including with trailing
options.
rtla timerlat hist -T50 -t
Works as expected "timerlat_trace.txt"
rtla timerlat hist -T50 --trace
Works as expected "timerlat_trace.txt"
rtla timerlat hist -T50 -t -u
Works as expected "timerlat_trace.txt"
rtla timerlat hist -T50 --trace -u
Works as expected "timerlat_trace.txt"
Link: https://lkml.kernel.org/r/20240515183024.59985-1-jkacur@redhat.com
Cc: Daniel Bristot de Oliveria <bristot@kernel.org>
Signed-off-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Tomas Glozar