[patch] lock validator: rtmutex unlock order annotation

[Ingo Molnar <mingo@elte.hu>]

Subject: lock validator: rtmutex unlock order annotation
From: Ingo Molnar <mingo@elte.hu>

rtmutex.c does a tricky piece of 'lock chain' logic spiced with trylock,
which has one particular codepath where we intentionally release the
locks in a different order as acquired. Annotate this for the lock
validator to not complain if CONFIG_DEBUG_NON_NESTED_UNLOCKS=y.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/rtmutex.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Index: linux/kernel/rtmutex.c
===================================================================
--- linux.orig/kernel/rtmutex.c
+++ linux/kernel/rtmutex.c
@@ -243,7 +243,8 @@ static int rt_mutex_adjust_prio_chain(ta
 	plist_add(&waiter->list_entry, &lock->wait_list);
 
 	/* Release the task */
-	spin_unlock_irqrestore(&task->pi_lock, flags);
+	spin_unlock_non_nested(&task->pi_lock);
+	local_irq_restore(flags);
 	put_task_struct(task);
 
 	/* Grab the next task */