---

yaml
---
r: 30819
b: refs/heads/master
c: 95e02ca
h: refs/heads/master
i:
  30817: 956573a
  30815: b1a3e37
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 0bafd214e4ba55dc1fb81a3031d0249292f1bc05
+refs/heads/master: 95e02ca9bb5324360e7dea1ea1c563036d84a5e6

trunk/include/linux/sched.h

@@ -1044,11 +1044,13 @@ extern void sched_idle_next(void);
 #ifdef CONFIG_RT_MUTEXES
 extern int rt_mutex_getprio(task_t *p);
 extern void rt_mutex_setprio(task_t *p, int prio);
+extern void rt_mutex_adjust_pi(task_t *p);
 #else
 static inline int rt_mutex_getprio(task_t *p)
 {
 	return p->normal_prio;
 }
+# define rt_mutex_adjust_pi(p)		do { } while (0)
 #endif
 
 extern void set_user_nice(task_t *p, long nice);

trunk/kernel/rtmutex.c

@@ -160,7 +160,8 @@ int max_lock_depth = 1024;
 static int rt_mutex_adjust_prio_chain(task_t *task,
 				      int deadlock_detect,
 				      struct rt_mutex *orig_lock,
-				      struct rt_mutex_waiter *orig_waiter
+				      struct rt_mutex_waiter *orig_waiter,
+				      struct task_struct *top_task
 				      __IP_DECL__)
 {
 	struct rt_mutex *lock;
@@ -189,7 +190,7 @@ static int rt_mutex_adjust_prio_chain(task_t *task,
 			prev_max = max_lock_depth;
 			printk(KERN_WARNING "Maximum lock depth %d reached "
 			       "task: %s (%d)\n", max_lock_depth,
-			       current->comm, current->pid);
+			       top_task->comm, top_task->pid);
 		}
 		put_task_struct(task);
 
@@ -229,7 +230,7 @@ static int rt_mutex_adjust_prio_chain(task_t *task,
 	}
 
 	/* Deadlock detection */
-	if (lock == orig_lock || rt_mutex_owner(lock) == current) {
+	if (lock == orig_lock || rt_mutex_owner(lock) == top_task) {
 		debug_rt_mutex_deadlock(deadlock_detect, orig_waiter, lock);
 		spin_unlock(&lock->wait_lock);
 		ret = deadlock_detect ? -EDEADLK : 0;
@@ -433,6 +434,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
 		__rt_mutex_adjust_prio(owner);
 		if (owner->pi_blocked_on) {
 			boost = 1;
+			/* gets dropped in rt_mutex_adjust_prio_chain()! */
 			get_task_struct(owner);
 		}
 		spin_unlock_irqrestore(&owner->pi_lock, flags);
@@ -441,6 +443,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
 		spin_lock_irqsave(&owner->pi_lock, flags);
 		if (owner->pi_blocked_on) {
 			boost = 1;
+			/* gets dropped in rt_mutex_adjust_prio_chain()! */
 			get_task_struct(owner);
 		}
 		spin_unlock_irqrestore(&owner->pi_lock, flags);
@@ -450,8 +453,8 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
 
 	spin_unlock(&lock->wait_lock);
 
-	res = rt_mutex_adjust_prio_chain(owner, detect_deadlock, lock,
-					 waiter __IP__);
+	res = rt_mutex_adjust_prio_chain(owner, detect_deadlock, lock, waiter,
+					 current __IP__);
 
 	spin_lock(&lock->wait_lock);
 
@@ -552,6 +555,7 @@ static void remove_waiter(struct rt_mutex *lock,
 
 		if (owner->pi_blocked_on) {
 			boost = 1;
+			/* gets dropped in rt_mutex_adjust_prio_chain()! */
 			get_task_struct(owner);
 		}
 		spin_unlock_irqrestore(&owner->pi_lock, flags);
@@ -564,11 +568,36 @@ static void remove_waiter(struct rt_mutex *lock,
 
 	spin_unlock(&lock->wait_lock);
 
-	rt_mutex_adjust_prio_chain(owner, 0, lock, NULL __IP__);
+	rt_mutex_adjust_prio_chain(owner, 0, lock, NULL, current __IP__);
 
 	spin_lock(&lock->wait_lock);
 }
 
+/*
+ * Recheck the pi chain, in case we got a priority setting
+ *
+ * Called from sched_setscheduler
+ */
+void rt_mutex_adjust_pi(struct task_struct *task)
+{
+	struct rt_mutex_waiter *waiter;
+	unsigned long flags;
+
+	spin_lock_irqsave(&task->pi_lock, flags);
+
+	waiter = task->pi_blocked_on;
+	if (!waiter || waiter->list_entry.prio == task->prio) {
+		spin_unlock_irqrestore(&task->pi_lock, flags);
+		return;
+	}
+
+	/* gets dropped in rt_mutex_adjust_prio_chain()! */
+	get_task_struct(task);
+	spin_unlock_irqrestore(&task->pi_lock, flags);
+
+	rt_mutex_adjust_prio_chain(task, 0, NULL, NULL, task __RET_IP__);
+}
+
 /*
  * Slow path lock function:
  */
@@ -636,6 +665,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
 			if (unlikely(ret))
 				break;
 		}
+
 		spin_unlock(&lock->wait_lock);
 
 		debug_rt_mutex_print_deadlock(&waiter);

trunk/kernel/sched.c

@@ -4070,6 +4070,8 @@ int sched_setscheduler(struct task_struct *p, int policy,
 	__task_rq_unlock(rq);
 	spin_unlock_irqrestore(&p->pi_lock, flags);
 
+	rt_mutex_adjust_pi(p);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(sched_setscheduler);