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

Steven Rostedt (Red Hat) committed 11 years ago

Commit 799fd441 parent fb662281 file · +7 −6Browse files

Unified · Split

kernel/trace/trace_events.c+7−6

 						 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.
-		 */
-		on_each_cpu(ignore_task_cpu, tr, 1);
 	}
+	/*
+	 * 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);
 	ret = read;