Commit 799fd44c authored Nov 02, 2015 by Steven Rostedt (Red Hat) Committed by Steven Rostedt Nov 02, 2015

tracing: Call on_each_cpu() when adding or removing single pids from set_event_pid

For the case where pids are already in set_event_pid, and one is added or
removed then each CPU should be checked to make sure that the new or old pid
is on or not on a CPU.

 For example:

 # echo 123 >> set_event_pid

or

 # echo '!123' >> set_event_pid

Link: http://lkml.kernel.org/r/20151030061643.GA19480@cac



Suggested-by: Jiaxing Wang <hello.wjx@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

parent fb662288

kernel/trace/trace_events.c

+7 −6

Original line number	Diff line number	Diff line
		@@ -1729,13 +1729,14 @@ ftrace_event_pid_write(struct file filp, const char __user ubuf,
		tr, INT_MAX);
		register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_post,
		tr, 0);
		}

		/*
		* Ignoring of pids is done at task switch. But we have to
		* check for those tasks that are currently running.
		* Always do this in case a pid was appended or removed.
		*/
		on_each_cpu(ignore_task_cpu, tr, 1);
		}

		mutex_unlock(&event_mutex);