diff options
Diffstat (limited to 'Documentation/tools/rtla')
| -rw-r--r-- | Documentation/tools/rtla/common_appendix.rst | 11 | ||||
| -rw-r--r-- | Documentation/tools/rtla/common_timerlat_options.rst | 64 | ||||
| -rw-r--r-- | Documentation/tools/rtla/rtla-timerlat-hist.rst | 2 |
3 files changed, 77 insertions, 0 deletions
diff --git a/Documentation/tools/rtla/common_appendix.rst b/Documentation/tools/rtla/common_appendix.rst index b5cf2dc223df..53cae7537537 100644 --- a/Documentation/tools/rtla/common_appendix.rst +++ b/Documentation/tools/rtla/common_appendix.rst @@ -1,3 +1,14 @@ +.. SPDX-License-Identifier: GPL-2.0 + +EXIT STATUS +=========== + +:: + + 0 Passed: the test did not hit the stop tracing condition + 1 Error: invalid argument + 2 Failed: the test hit the stop tracing condition + REPORTING BUGS ============== Report bugs to <linux-kernel@vger.kernel.org> diff --git a/Documentation/tools/rtla/common_timerlat_options.rst b/Documentation/tools/rtla/common_timerlat_options.rst index 10dc802f8d65..7854368f1827 100644 --- a/Documentation/tools/rtla/common_timerlat_options.rst +++ b/Documentation/tools/rtla/common_timerlat_options.rst @@ -55,3 +55,67 @@ 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. diff --git a/Documentation/tools/rtla/rtla-timerlat-hist.rst b/Documentation/tools/rtla/rtla-timerlat-hist.rst index 03b7f3deb069..b2d8726271b3 100644 --- a/Documentation/tools/rtla/rtla-timerlat-hist.rst +++ b/Documentation/tools/rtla/rtla-timerlat-hist.rst @@ -107,3 +107,5 @@ SEE ALSO AUTHOR ====== Written by Daniel Bristot de Oliveira <bristot@kernel.org> + +.. include:: common_appendix.rst |