[PATCH v2 1/5] mutex: In mutex_can_spin_on_owner(), return false if task need_resched()

[Jason Low]

The mutex_can_spin_on_owner() function should also return false if the
task needs to be rescheduled to avoid entering the MCS queue when it
needs to reschedule.

Signed-off-by: Jason Low <jason.low2@xxxxxx>
---
 kernel/locking/mutex.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 4dd6e4c..85c6be1 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -212,6 +212,9 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock)
 	struct task_struct *owner;
 	int retval = 1;
 
+	if (need_resched())
+		return 0;
+
 	rcu_read_lock();
 	owner = ACCESS_ONCE(lock->owner);
 	if (owner)
-- 
1.7.1

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