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Diffstat (limited to 'Documentation/tools/rtla/common_timerlat_options.rst')
| -rw-r--r-- | Documentation/tools/rtla/common_timerlat_options.rst | 74 |
1 files changed, 10 insertions, 64 deletions
diff --git a/Documentation/tools/rtla/common_timerlat_options.rst b/Documentation/tools/rtla/common_timerlat_options.rst index 7854368f1827..1f5d024b53aa 100644 --- a/Documentation/tools/rtla/common_timerlat_options.rst +++ b/Documentation/tools/rtla/common_timerlat_options.rst @@ -1,3 +1,13 @@ +.. |threshold| replace:: **-a/--auto**, **-i/--irq**, or **-T/--thread** +.. |thresharg| replace:: -T +.. |tracer| replace:: timerlat + +.. |actionsperf| replace:: + For time-sensitive actions, it is recommended to run **rtla timerlat** with BPF + support and RT priority. Note that due to implementational limitations, actions + might be delayed up to one second after tracing is stopped if BPF mode is not + available or disabled. + **-a**, **--auto** *us* Set the automatic trace mode. This mode sets some commonly used options @@ -55,67 +65,3 @@ Set timerlat to run without workload, waiting for the user to dispatch a per-cpu task that waits for a new period on the tracing/osnoise/per_cpu/cpu$ID/timerlat_fd. See linux/tools/rtla/sample/timerlat_load.py for an example of user-load code. - -**--on-threshold** *action* - - Defines an action to be executed when tracing is stopped on a latency threshold - specified by **-i/--irq** or **-T/--thread**. - - Multiple --on-threshold actions may be specified, and they will be executed in - the order they are provided. If any action fails, subsequent actions in the list - will not be executed. - - Supported actions are: - - - *trace[,file=<filename>]* - - Saves trace output, optionally taking a filename. Alternative to -t/--trace. - Note that nlike -t/--trace, specifying this multiple times will result in - the trace being saved multiple times. - - - *signal,num=<sig>,pid=<pid>* - - Sends signal to process. "parent" might be specified in place of pid to target - the parent process of rtla. - - - *shell,command=<command>* - - Execute shell command. - - - *continue* - - Continue tracing after actions are executed instead of stopping. - - Example: - - $ rtla timerlat -T 20 --on-threshold trace - --on-threshold shell,command="grep ipi_send timerlat_trace.txt" - --on-threshold signal,num=2,pid=parent - - This will save a trace with the default filename "timerlat_trace.txt", print its - lines that contain the text "ipi_send" on standard output, and send signal 2 - (SIGINT) to the parent process. - - Performance Considerations: - - For time-sensitive actions, it is recommended to run **rtla timerlat** with BPF - support and RT priority. Note that due to implementational limitations, actions - might be delayed up to one second after tracing is stopped if BPF mode is not - available or disabled. - -**--on-end** *action* - - Defines an action to be executed at the end of **rtla timerlat** tracing. - - Multiple --on-end actions can be specified, and they will be executed in the order - they are provided. If any action fails, subsequent actions in the list will not be - executed. - - See the documentation for **--on-threshold** for the list of supported actions, with - the exception that *continue* has no effect. - - Example: - - $ rtla timerlat -d 5s --on-end trace - - This runs rtla timerlat with default options and save trace output at the end. |