rt-patches/0120-rtmutex-Add-rtmutex_lock_killable.patch

From fbbe78885fc3a4fa1a0dab152eaea7ff1c8a60cb Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 9 Jun 2011 11:43:52 +0200
Subject: [PATCH 120/366] rtmutex: Add rtmutex_lock_killable()

Add "killable" type to rtmutex. We need this since rtmutex are used as
"normal" mutexes which do use this type.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 include/linux/rtmutex.h  |  1 +
 kernel/locking/rtmutex.c | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
index 1abba5c..51dc12e 100644
--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -91,6 +91,7 @@ extern void rt_mutex_destroy(struct rt_mutex *lock);
 
 extern void rt_mutex_lock(struct rt_mutex *lock);
 extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
+extern int rt_mutex_lock_killable(struct rt_mutex *lock);
 extern int rt_mutex_timed_lock(struct rt_mutex *lock,
 			       struct hrtimer_sleeper *timeout);
 
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index f032647..d75967b 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1458,6 +1458,25 @@ int rt_mutex_timed_futex_lock(struct rt_mutex *lock,
 }
 
 /**
+ * rt_mutex_lock_killable - lock a rt_mutex killable
+ *
+ * @lock:              the rt_mutex to be locked
+ * @detect_deadlock:   deadlock detection on/off
+ *
+ * Returns:
+ *  0          on success
+ * -EINTR      when interrupted by a signal
+ * -EDEADLK    when the lock would deadlock (when deadlock detection is on)
+ */
+int __sched rt_mutex_lock_killable(struct rt_mutex *lock)
+{
+	might_sleep();
+
+	return rt_mutex_fastlock(lock, TASK_KILLABLE, rt_mutex_slowlock);
+}
+EXPORT_SYMBOL_GPL(rt_mutex_lock_killable);
+
+/**
  * rt_mutex_timed_lock - lock a rt_mutex interruptible
  *			the timeout structure is provided
  *			by the caller
-- 
1.9.1