diff options
| author | Jason Low <jason.low2@hp.com> | 2014-01-28 20:13:12 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2014-03-11 12:14:52 +0100 |
| commit | 46af29e479cc0c1c63633007993af5292c2c3e75 (patch) | |
| tree | 2d229487a929757e062cd9765263023ef762f1f9 | |
| parent | locking: Move mcs_spinlock.h into kernel/locking/ (diff) | |
| download | linux-46af29e479cc0c1c63633007993af5292c2c3e75.tar.xz linux-46af29e479cc0c1c63633007993af5292c2c3e75.zip | |
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@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Waiman.Long@hp.com
Cc: torvalds@linux-foundation.org
Cc: tglx@linutronix.de
Cc: riel@redhat.com
Cc: akpm@linux-foundation.org
Cc: davidlohr@hp.com
Cc: hpa@zytor.com
Cc: andi@firstfloor.org
Cc: aswin@hp.com
Cc: scott.norton@hp.com
Cc: chegu_vinod@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1390936396-3962-2-git-send-email-jason.low2@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | 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 4f408be39a07..e6d646b18d6c 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) |