Exit right away, when the removed waiter was not the top prioriy waiter on the lock. Get rid of the extra indent level. Signed-off-by: Thomas Gleixner --- kernel/locking/rtmutex.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) Index: tip/kernel/locking/rtmutex.c =================================================================== --- tip.orig/kernel/locking/rtmutex.c +++ tip/kernel/locking/rtmutex.c @@ -920,9 +920,9 @@ static void wakeup_next_waiter(struct rt static void remove_waiter(struct rt_mutex *lock, struct rt_mutex_waiter *waiter) { - int first = (waiter == rt_mutex_top_waiter(lock)); + bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock)); struct task_struct *owner = rt_mutex_owner(lock); - struct rt_mutex *next_lock = NULL; + struct rt_mutex *next_lock; unsigned long flags; raw_spin_lock_irqsave(¤t->pi_lock, flags); @@ -930,29 +930,31 @@ static void remove_waiter(struct rt_mute current->pi_blocked_on = NULL; raw_spin_unlock_irqrestore(¤t->pi_lock, flags); - if (!owner) + /* + * Only update priority if the waiter was the highest priority + * waiter of the lock and there is an owner to update. + */ + if (!owner || !is_top_waiter) return; - if (first) { + raw_spin_lock_irqsave(&owner->pi_lock, flags); - raw_spin_lock_irqsave(&owner->pi_lock, flags); + rt_mutex_dequeue_pi(owner, waiter); - rt_mutex_dequeue_pi(owner, waiter); + if (rt_mutex_has_waiters(lock)) + rt_mutex_enqueue_pi(owner, rt_mutex_top_waiter(lock)); - if (rt_mutex_has_waiters(lock)) { - struct rt_mutex_waiter *next; + __rt_mutex_adjust_prio(owner); - next = rt_mutex_top_waiter(lock); - rt_mutex_enqueue_pi(owner, next); - } - __rt_mutex_adjust_prio(owner); + /* Store the lock on which owner is blocked or NULL */ + next_lock = task_blocked_on_lock(owner); - /* Store the lock on which owner is blocked or NULL */ - next_lock = task_blocked_on_lock(owner); - - raw_spin_unlock_irqrestore(&owner->pi_lock, flags); - } + raw_spin_unlock_irqrestore(&owner->pi_lock, flags); + /* + * Don't walk the chain, if the owner task is not blocked + * itself. + */ if (!next_lock) return; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/