kernel.git/tools/tracing/rtla/src/osnoise.c, branch master

rtla: Set stop threshold after all instances are enabled

2026-01-07T14:57:15Z

This avoids startup races where one of the instances hit a threshold before all instances were enabled, and thus tracing stops without the relevant event. In particular, this is not uncommon with the tests that set a very tight threshold and then complain if there's no analysis. This also ensures that we don't stop tracing during a warmup. The downside is a small chance of having an event over the threshold early in the output, without stopping on it, which could cause user confusion. This should be less likely if the warmup feature is used, but that doesn't eliminate the race window, just the odds of an unusual spike right at that moment. Signed-off-by: Crystal Wood Link: https://lore.kernel.org/r/20251112152529.956778-6-crwood@redhat.com Signed-off-by: Tomas Glozar

tools/rtla: Consolidate code between osnoise/timerlat and hist/top

2025-09-27T08:52:57Z

Currently a lot of code is duplicated between the different rtla tools, making maintenance more difficult, and encouraging divergence such as features that are only implemented for certain tools even though they could be more broadly applicable. Merge the various main() functions into a common run_tool() with an ops struct for tool-specific details. Implement enough support for actions on osnoise to not need to keep the old params->trace_output path. Cc: John Kacur Cc: Costa Shulyupin Link: https://lore.kernel.org/20250907022325.243930-5-crwood@redhat.com Reviewed-by: Tomas Glozar Signed-off-by: Crystal Wood Signed-off-by: Steven Rostedt (Google)

tools/rtla: Create common_apply_config()

2025-09-27T08:52:46Z

Merge the common bits of osnoise_apply_config() and timerlat_apply_config(). Put the result in a new common.c, and move enough things to common.h so that common.c does not need to include osnoise.h. Cc: John Kacur Cc: Costa Shulyupin Link: https://lore.kernel.org/20250907022325.243930-4-crwood@redhat.com Reviewed-by: Tomas Glozar Signed-off-by: Crystal Wood Signed-off-by: Steven Rostedt (Google)

tools/rtla: Consolidate common parameters into shared structure

2025-09-27T08:51:18Z

timerlat_params and osnoise_params structures contain 15 identical fields. Introduce a new header common.h and define a common_params structure to consolidate shared fields, reduce code duplication, and enhance maintainability. Cc: John Kacur Link: https://lore.kernel.org/20250907022325.243930-2-crwood@redhat.com Reviewed-by: Tomas Glozar Signed-off-by: Costa Shulyupin Signed-off-by: Crystal Wood Signed-off-by: Steven Rostedt (Google)

rtla: Always set all tracer options

2025-03-26T14:36:39Z

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 Link: https://lore.kernel.org/20250320092500.101385-5-tglozar@redhat.com Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode") Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode") Fixes: a828cd18bc4a ("rtla: Add timerlat tool and timelart top mode") Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode") Signed-off-by: Tomas Glozar Reviewed-by: John Kacur Signed-off-by: Steven Rostedt (Google)

rtla/osnoise: Set OSNOISE_WORKLOAD to true

2025-03-26T14:36:39Z

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 217f0b1e990e ("rtla/timerlat_top: Set OSNOISE_WORKLOAD for kernel threads") and commit d8d866171a41 ("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 Link: https://lore.kernel.org/20250320092500.101385-4-tglozar@redhat.com Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode") Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode") Signed-off-by: Tomas Glozar Reviewed-by: John Kacur Signed-off-by: Steven Rostedt (Google)

rtla: Unify apply_config between top and hist

2025-03-26T14:36:39Z

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 Link: https://lore.kernel.org/20250320092500.101385-3-tglozar@redhat.com Signed-off-by: Tomas Glozar Reviewed-by: John Kacur Signed-off-by: Steven Rostedt (Google)

rtla/osnoise: Unify params struct

2025-03-26T14:36:39Z

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 Link: https://lore.kernel.org/20250320092500.101385-2-tglozar@redhat.com Signed-off-by: Tomas Glozar Reviewed-by: John Kacur Signed-off-by: Steven Rostedt (Google)

rtla: Add function to report missed events

2025-01-24T18:46:43Z

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 Cc: Luis Goncalves Cc: Gabriele Monaco Link: https://lore.kernel.org/20250123142339.990300-4-tglozar@redhat.com Signed-off-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)

tools/rtla: Add osnoise_trace_is_off()

2025-01-24T18:46:11Z

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 Cc: "Luis Claudio R. Goncalves" Cc: Eder Zulian Cc: Dan Carpenter Cc: Tomas Glozar Cc: Gabriele Monaco Link: https://lore.kernel.org/20250115180055.2136815-1-costa.shul@redhat.com Signed-off-by: Costa Shulyupin Signed-off-by: Steven Rostedt (Google)