diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2014-06-07 09:36:13 +0200 |
---|---|---|
committer | Anders Roxell <anders.roxell@linaro.org> | 2015-03-23 09:31:11 +0100 |
commit | 228593540fef501b4bdf9aba577f232fb3ec8b42 (patch) | |
tree | 42ea385f0dce3b26bf6eba147cfdec6c3e9fba0a | |
parent | 2f1384d24458ea1eddf300148b7a739ad2ab1a89 (diff) |
rtmutex: Simplify remove_waiter()
upstream commit: 1ca7b86062ec8473d03c5cdfd336abc8b1c8098c
Exit right away, when the removed waiter was not the top priority
waiter on the lock. Get rid of the extra indent level.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Conflicts:
kernel/locking/rtmutex.c
-rw-r--r-- | kernel/locking/rtmutex.c | 36 |
1 files changed, 19 insertions, 17 deletions
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 400026ec7f05..6c74a0525dcb 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -985,7 +985,7 @@ static void wakeup_next_waiter(struct rt_mutex *lock) 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; unsigned long flags; @@ -995,30 +995,32 @@ static void remove_waiter(struct rt_mutex *lock, 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 */ - if (rt_mutex_real_waiter(owner->pi_blocked_on)) - next_lock = task_blocked_on_lock(owner); + /* Store the lock on which owner is blocked or NULL */ + if (rt_mutex_real_waiter(owner->pi_blocked_on)) + 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; |