rtmutex: No need to keep task ref for lock owner check

There is no point to keep the task ref across the check for lock
owner. Drop the ref before that, so the protection context is clear.

Found while documenting the chain walk.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
This commit is contained in:
Thomas Gleixner 2014-06-07 12:10:36 +02:00
parent 358c331f39
commit 2ffa5a5cd2

View File

@ -463,6 +463,8 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
/* Release the task */
raw_spin_unlock_irqrestore(&task->pi_lock, flags);
put_task_struct(task);
if (!rt_mutex_owner(lock)) {
/*
* If the requeue above changed the top waiter, then we need
@ -472,9 +474,8 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
if (top_waiter != rt_mutex_top_waiter(lock))
wake_up_process(rt_mutex_top_waiter(lock)->task);
raw_spin_unlock(&lock->wait_lock);
goto out_put_task;
return 0;
}
put_task_struct(task);
/* Grab the next task */
task = rt_mutex_owner(lock);