[PATCH 1/1] sched: fix the PREEMPT_ACTIVE check in __trace_sched_switch_state()

[Oleg Nesterov]

task_preempt_count() has nothing to do with the actual preempt counter,
thread_info->saved_preempt_count is only valid right after switch_to().

__trace_sched_switch_state() can use preempt_count(), prev is still the
current task when trace_sched_switch() is called.

Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
---
 include/trace/events/sched.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index 0a68d5a..a7d67bc 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -100,7 +100,7 @@ static inline long __trace_sched_switch_state(struct task_struct *p)
 	/*
 	 * For all intents and purposes a preempted task is a running task.
 	 */
-	if (task_preempt_count(p) & PREEMPT_ACTIVE)
+	if (preempt_count() & PREEMPT_ACTIVE)
 		state = TASK_RUNNING | TASK_STATE_MAX;
 #endif
 
-- 
1.5.5.1


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