tracing: Robustify wait loop
The pending nested sleep debugging triggered on the potential stale
TASK_INTERRUPTIBLE in this code.
While there, fix the loop such that we won't revert to a while(1)
yield() 'spin' loop if we ever get a spurious wakeup.
And fix the actual issue by properly terminating the 'wait' loop by
setting TASK_RUNNING.
Link: http://lkml.kernel.org/p/20141008165110.GA14547@worktop.programming.kicks-ass.net
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index ef06ce7..0cc51ed 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2513,8 +2513,11 @@
kfree(test_malloc);
set_current_state(TASK_INTERRUPTIBLE);
- while (!kthread_should_stop())
+ while (!kthread_should_stop()) {
schedule();
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
+ __set_current_state(TASK_RUNNING);
return 0;
}