Commit-ID: 94247f76e7361afd85ba03a3f923bf3d07ba3017
Gitweb: http://git.kernel.org/tip/94247f76e7361afd85ba03a3f923bf3d07ba3017
Author: Mike Galbraith <[email protected]>
AuthorDate: Wed, 5 Apr 2017 10:08:27 +0200
Committer: Thomas Gleixner <[email protected]>
CommitDate: Wed, 5 Apr 2017 16:52:10 +0200
Retiplockingcore_rtmutex_Deboost_before_waking_up_the_top_waiter
mark_wakeup_next_waiter() already disables preemption, doing so again
leaves us with an unpaired preempt_disable().
Fixes: 2a1c60299406 ("rtmutex: Deboost before waking up the top waiter")
Signed-off-by: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
---
kernel/locking/rtmutex.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 0e641eb..b955094 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1581,13 +1581,13 @@ bool __sched __rt_mutex_futex_unlock(struct rt_mutex
*lock,
return false; /* done */
}
- mark_wakeup_next_waiter(wake_q, lock);
/*
- * We've already deboosted, retain preempt_disabled when dropping
- * the wait_lock to avoid inversion until the wakeup. Matched
- * by rt_mutex_postunlock();
+ * We've already deboosted, mark_wakeup_next_waiter() will
+ * retain preempt_disabled when we drop the wait_lock, to
+ * avoid inversion prior to the wakeup. preempt_disable()
+ * therein pairs with rt_mutex_postunlock().
*/
- preempt_disable();
+ mark_wakeup_next_waiter(wake_q, lock);
return true; /* call postunlock() */
}
