Commit 1ce25e9f authored Nov 05, 2018 by Masami Hiramatsu Committed by Steven Rostedt (VMware) Dec 10, 2018

tracing: Add generic event-name based remove event method

Add a generic method to remove event from dynamic event
list. This is same as other system under ftrace. You
just need to pass the event name with '!', e.g.

  # echo p:new_grp/new_event _do_fork > dynamic_events

This creates an event, and

  # echo '!p:new_grp/new_event _do_fork' > dynamic_events

Or,

  # echo '!p:new_grp/new_event' > dynamic_events

will remove new_grp/new_event event.

Note that this doesn't check the event prefix (e.g. "p:")
strictly, because the "group/event" name must be unique.

Link: http://lkml.kernel.org/r/154140869774.17322.8887303560398645347.stgit@devbox



Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

parent 7e1413ed

kernel/trace/trace_dynevent.c

+11 −4

Original line number	Diff line number	Diff line
		@@ -37,10 +37,17 @@ int dyn_event_release(int argc, char *argv, struct dyn_event_operations type)
		char system = NULL, event, *p;
		int ret = -ENOENT;

		if (argv[0][0] == '-') {
		if (argv[0][1] != ':')
		return -EINVAL;

		event = &argv[0][2];
		} else {
		event = strchr(argv[0], ':');
		if (!event)
		return -EINVAL;
		event++;
		}

		p = strchr(event, '/');
		if (p) {
		system = event;
		@@ -69,7 +76,7 @@ static int create_dyn_event(int argc, char **argv)
		struct dyn_event_operations *ops;
		int ret;

		if (argv[0][0] == '-')
		if (argv[0][0] == '-' \|\| argv[0][0] == '!')
		return dyn_event_release(argc, argv, NULL);

		mutex_lock(&dyn_event_ops_mutex);

Admin message