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+**-a**, **--auto** *us*
+
+ Set the automatic trace mode. This mode sets some commonly used options
+ while debugging the system. It is equivalent to use **-T** *us* **-s** *us*
+ **-t**. By default, *timerlat* tracer uses FIFO:95 for *timerlat* threads,
+ thus equilavent to **-P** *f:95*.
+
+**-p**, **--period** *us*
+
+ Set the *timerlat* tracer period in microseconds.
+
+**-i**, **--irq** *us*
+
+ Stop trace if the *IRQ* latency is higher than the argument in us.
+
+**-T**, **--thread** *us*
+
+ Stop trace if the *Thread* latency is higher than the argument in us.
+
+**-s**, **--stack** *us*
+
+ Save the stack trace at the *IRQ* if a *Thread* latency is higher than the
+ argument in us.
+
+**-t**, **--trace** \[*file*]
+
+ Save the stopped trace to [*file|timerlat_trace.txt*].
+
+**--dma-latency** *us*
+ Set the /dev/cpu_dma_latency to *us*, aiming to bound exit from idle latencies.
+ *cyclictest* sets this value to *0* by default, use **--dma-latency** *0* to have
+ similar results.
+
+**--deepest-idle-state** *n*
+ Disable idle states higher than *n* for cpus that are running timerlat threads to
+ reduce exit from idle latencies. If *n* is -1, all idle states are disabled.
+ On exit from timerlat, the idle state setting is restored to its original state
+ before running timerlat.
+
+ Requires rtla to be built with libcpupower.
+
+**-k**, **--kernel-threads**
+
+ Use timerlat kernel-space threads, in contrast of **-u**.
+
+**-u**, **--user-threads**
+
+ Set timerlat to run without a workload, and then dispatches user-space workloads
+ to wait on the timerlat_fd. Once the workload is awakes, it goes to sleep again
+ adding so the measurement for the kernel-to-user and user-to-kernel to the tracer
+ output. **--user-threads** will be used unless the user specify **-k**.
+
+**-U**, **--user-load**
+
+ 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.