Commit-ID: 46af29e479cc0c1c63633007993af5292c2c3e75 Gitweb: http://git.kernel.org/tip/46af29e479cc0c1c63633007993af5292c2c3e75 Author: Jason Low <jason.low2@xxxxxx> AuthorDate: Tue, 28 Jan 2014 11:13:12 -0800 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Tue, 11 Mar 2014 12:14:52 +0100 locking/mutexes: Return false if task need_resched() in mutex_can_spin_on_owner() 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> Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Waiman.Long@xxxxxx Cc: torvalds@xxxxxxxxxxxxxxxxxxxx Cc: tglx@xxxxxxxxxxxxx Cc: riel@xxxxxxxxxx Cc: akpm@xxxxxxxxxxxxxxxxxxxx Cc: davidlohr@xxxxxx Cc: hpa@xxxxxxxxx Cc: andi@xxxxxxxxxxxxxx Cc: aswin@xxxxxx Cc: scott.norton@xxxxxx Cc: chegu_vinod@xxxxxx Cc: paulmck@xxxxxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/1390936396-3962-2-git-send-email-jason.low2@xxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- kernel/locking/mutex.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 4f408be..e6d646b 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -166,6 +166,9 @@ 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) -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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