diff options
Diffstat (limited to 'kernel/locking/rtmutex.c')
| -rw-r--r-- | kernel/locking/rtmutex.c | 29 |
1 files changed, 21 insertions, 8 deletions
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 71ecf0624410..bc05b104eaed 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -323,6 +323,19 @@ rt_mutex_dequeue_pi(struct task_struct *task, struct rt_mutex_waiter *waiter) } /* + * Must hold both p->pi_lock and task_rq(p)->lock. + */ +void rt_mutex_update_top_task(struct task_struct *p) +{ + if (!task_has_pi_waiters(p)) { + p->pi_top_task = NULL; + return; + } + + p->pi_top_task = task_top_pi_waiter(p)->task; +} + +/* * Calculate task priority from the waiter tree priority * * Return task->normal_prio when the waiter tree is empty or when @@ -337,12 +350,12 @@ int rt_mutex_getprio(struct task_struct *task) task->normal_prio); } +/* + * Must hold either p->pi_lock or task_rq(p)->lock. + */ struct task_struct *rt_mutex_get_top_task(struct task_struct *task) { - if (likely(!task_has_pi_waiters(task))) - return NULL; - - return task_top_pi_waiter(task)->task; + return task->pi_top_task; } /* @@ -351,12 +364,12 @@ struct task_struct *rt_mutex_get_top_task(struct task_struct *task) */ int rt_mutex_get_effective_prio(struct task_struct *task, int newprio) { - if (!task_has_pi_waiters(task)) + struct task_struct *top_task = rt_mutex_get_top_task(task); + + if (!top_task) return newprio; - if (task_top_pi_waiter(task)->task->prio <= newprio) - return task_top_pi_waiter(task)->task->prio; - return newprio; + return min(top_task->prio, newprio); } /* |