Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Add CONFIG_REFCOUNT_FULL=y to allow the disabling of the 'full'
     (robustness checked) refcount_t implementation with slightly lower
     runtime overhead. (Kees Cook)

     The lighter weight variant is the default. The two variants use the
     same API. Having this variant was a precondition by some
     maintainers to merge refcount_t cleanups.

   - Add lockdep support for rtmutexes (Peter Zijlstra)

   - liblockdep fixes and improvements (Sasha Levin, Ben Hutchings)

   - ... misc fixes and improvements"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  locking/refcount: Remove the half-implemented refcount_sub() API
  locking/refcount: Create unchecked atomic_t implementation
  locking/rtmutex: Don't initialize lockdep when not required
  locking/selftest: Add RT-mutex support
  locking/selftest: Remove the bad unlock ordering test
  rt_mutex: Add lockdep annotations
  MAINTAINERS: Claim atomic*_t maintainership
  locking/x86: Remove the unused atomic_inc_short() methd
  tools/lib/lockdep: Remove private kernel headers
  tools/lib/lockdep: Hide liblockdep output from test results
  tools/lib/lockdep: Add dummy current_gfp_context()
  tools/include: Add IS_ERR_OR_NULL to err.h
  tools/lib/lockdep: Add empty __is_[module,kernel]_percpu_address
  tools/lib/lockdep: Include err.h
  tools/include: Add (mostly) empty include/linux/sched/mm.h
  tools/lib/lockdep: Use LDFLAGS
  tools/lib/lockdep: Remove double-quotes from soname
  tools/lib/lockdep: Fix object file paths used in an out-of-tree build
  tools/lib/lockdep: Fix compilation for 4.11
  tools/lib/lockdep: Don't mix fd-based and stream IO
  ...

kernel/locking/rtmutex-debug.c

@@ -166,12 +166,16 @@ void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter)
 	memset(waiter, 0x22, sizeof(*waiter));
 }
 
-void debug_rt_mutex_init(struct rt_mutex *lock, const char *name)
+void debug_rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key)
 {
 	/*
 	 * Make sure we are not reinitializing a held lock:
 	 */
 	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
 	lock->name = name;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
 }
 

kernel/locking/rtmutex-debug.h

@@ -11,7 +11,7 @@
 
 extern void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
 extern void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter);
-extern void debug_rt_mutex_init(struct rt_mutex *lock, const char *name);
+extern void debug_rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key);
 extern void debug_rt_mutex_lock(struct rt_mutex *lock);
 extern void debug_rt_mutex_unlock(struct rt_mutex *lock);
 extern void debug_rt_mutex_proxy_lock(struct rt_mutex *lock,

kernel/locking/rtmutex.c

@@ -1481,6 +1481,7 @@ void __sched rt_mutex_lock(struct rt_mutex *lock)
 {
 	might_sleep();
 
+	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
 	rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_lock);
@@ -1496,9 +1497,16 @@ EXPORT_SYMBOL_GPL(rt_mutex_lock);
  */
 int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
 {
+	int ret;
+
 	might_sleep();
 
-	return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock);
+	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+	ret = rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock);
+	if (ret)
+		mutex_release(&lock->dep_map, 1, _RET_IP_);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
 
@@ -1526,11 +1534,18 @@ int __sched rt_mutex_futex_trylock(struct rt_mutex *lock)
 int
 rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout)
 {
+	int ret;
+
 	might_sleep();
 
-	return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
+	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+	ret = rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
 				       RT_MUTEX_MIN_CHAINWALK,
 				       rt_mutex_slowlock);
+	if (ret)
+		mutex_release(&lock->dep_map, 1, _RET_IP_);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
 
@@ -1547,10 +1562,16 @@ EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
  */
 int __sched rt_mutex_trylock(struct rt_mutex *lock)
 {
+	int ret;
+
 	if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
 		return 0;
 
-	return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
+	ret = rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
+	if (ret)
+		mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(rt_mutex_trylock);
 
@@ -1561,6 +1582,7 @@ EXPORT_SYMBOL_GPL(rt_mutex_trylock);
  */
 void __sched rt_mutex_unlock(struct rt_mutex *lock)
 {
+	mutex_release(&lock->dep_map, 1, _RET_IP_);
 	rt_mutex_fastunlock(lock, rt_mutex_slowunlock);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_unlock);
@@ -1620,7 +1642,6 @@ void rt_mutex_destroy(struct rt_mutex *lock)
 	lock->magic = NULL;
 #endif
 }
-
 EXPORT_SYMBOL_GPL(rt_mutex_destroy);
 
 /**
@@ -1632,14 +1653,16 @@ EXPORT_SYMBOL_GPL(rt_mutex_destroy);
  *
  * Initializing of a locked rt lock is not allowed
  */
-void __rt_mutex_init(struct rt_mutex *lock, const char *name)
+void __rt_mutex_init(struct rt_mutex *lock, const char *name,
+		     struct lock_class_key *key)
 {
 	lock->owner = NULL;
 	raw_spin_lock_init(&lock->wait_lock);
 	lock->waiters = RB_ROOT;
 	lock->waiters_leftmost = NULL;
 
-	debug_rt_mutex_init(lock, name);
+	if (name && key)
+		debug_rt_mutex_init(lock, name, key);
 }
 EXPORT_SYMBOL_GPL(__rt_mutex_init);
 
@@ -1660,7 +1683,7 @@ EXPORT_SYMBOL_GPL(__rt_mutex_init);
 void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
 				struct task_struct *proxy_owner)
 {
-	__rt_mutex_init(lock, NULL);
+	__rt_mutex_init(lock, NULL, NULL);
 	debug_rt_mutex_proxy_lock(lock, proxy_owner);
 	rt_mutex_set_owner(lock, proxy_owner);
 }

kernel/locking/rtmutex.h

@@ -17,7 +17,7 @@
 #define debug_rt_mutex_proxy_lock(l,p)			do { } while (0)
 #define debug_rt_mutex_proxy_unlock(l)			do { } while (0)
 #define debug_rt_mutex_unlock(l)			do { } while (0)
-#define debug_rt_mutex_init(m, n)			do { } while (0)
+#define debug_rt_mutex_init(m, n, k)			do { } while (0)
 #define debug_rt_mutex_deadlock(d, a ,l)		do { } while (0)
 #define debug_rt_mutex_print_deadlock(w)		do { } while (0)
 #define debug_rt_mutex_reset_waiter(w)			do { } while (0)