tracing: Add documentation on set_ftrace_notrace_pid and set_event_notrace_pid (2ab2a092) · Commits · 戴 / test

Documentation/trace/ftrace.rst

+31 −0

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		@@ -263,6 +263,20 @@ of ftrace. Here is a list of some of the key files:
		traced by the function tracer as well. This option will also
		cause PIDs of tasks that exit to be removed from the file.

		set_ftrace_notrace_pid:

		Have the function tracer ignore threads whose PID are listed in
		this file.

		If the "function-fork" option is set, then when a task whose
		PID is listed in this file forks, the child's PID will
		automatically be added to this file, and the child will not be
		traced by the function tracer as well. This option will also
		cause PIDs of tasks that exit to be removed from the file.

		If a PID is in both this file and "set_ftrace_pid", then this
		file takes precedence, and the thread will not be traced.

		set_event_pid:

		Have the events only trace a task with a PID listed in this file.
		@@ -274,6 +288,19 @@ of ftrace. Here is a list of some of the key files:
		cause the PIDs of tasks to be removed from this file when the task
		exits.

		set_event_notrace_pid:

		Have the events not trace a task with a PID listed in this file.
		Note, sched_switch and sched_wakeup will trace threads not listed
		in this file, even if a thread's PID is in the file if the
		sched_switch or sched_wakeup events also trace a thread that should
		be traced.

		To have the PIDs of children of tasks with their PID in this file
		added on fork, enable the "event-fork" option. That option will also
		cause the PIDs of tasks to be removed from this file when the task
		exits.

		set_graph_function:

		Functions listed in this file will cause the function graph
		@@ -1183,6 +1210,8 @@ Here are the available options:
		tasks fork. Also, when tasks with PIDs in set_event_pid exit,
		their PIDs will be removed from the file.

		This affects PIDs listed in set_event_notrace_pid as well.

		function-trace
		The latency tracers will enable function tracing
		if this option is enabled (default it is). When
		@@ -1197,6 +1226,8 @@ Here are the available options:
		set_ftrace_pid exit, their PIDs will be removed from the
		file.

		This affects PIDs in set_ftrace_notrace_pid as well.

		display-graph
		When set, the latency tracers (irqsoff, wakeup, etc) will
		use function graph tracing instead of function tracing.

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