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:

   - A comprehensive rewrite of the robust/PI futex code's exit handling
     to fix various exit races. (Thomas Gleixner et al)

   - Rework the generic REFCOUNT_FULL implementation using
     atomic_fetch_* operations so that the performance impact of the
     cmpxchg() loops is mitigated for common refcount operations.

     With these performance improvements the generic implementation of
     refcount_t should be good enough for everybody - and this got
     confirmed by performance testing, so remove ARCH_HAS_REFCOUNT and
     REFCOUNT_FULL entirely, leaving the generic implementation enabled
     unconditionally. (Will Deacon)

   - Other misc changes, fixes, cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  lkdtm: Remove references to CONFIG_REFCOUNT_FULL
  locking/refcount: Remove unused 'refcount_error_report()' function
  locking/refcount: Consolidate implementations of refcount_t
  locking/refcount: Consolidate REFCOUNT_{MAX,SATURATED} definitions
  locking/refcount: Move saturation warnings out of line
  locking/refcount: Improve performance of generic REFCOUNT_FULL code
  locking/refcount: Move the bulk of the REFCOUNT_FULL implementation into the <linux/refcount.h> header
  locking/refcount: Remove unused refcount_*_checked() variants
  locking/refcount: Ensure integer operands are treated as signed
  locking/refcount: Define constants for saturation and max refcount values
  futex: Prevent exit livelock
  futex: Provide distinct return value when owner is exiting
  futex: Add mutex around futex exit
  futex: Provide state handling for exec() as well
  futex: Sanitize exit state handling
  futex: Mark the begin of futex exit explicitly
  futex: Set task::futex_state to DEAD right after handling futex exit
  futex: Split futex_mm_release() for exit/exec
  exit/exec: Seperate mm_release()
  futex: Replace PF_EXITPIDONE with a state
  ...

4 files changed, 16 insertions, 15 deletions

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 233459c03b5a..32282e7112d3 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -4208,11 +4208,9 @@ static int __lock_downgrade(struct lockdep_map *lock, unsigned long ip)
 }
 
 /*
- * Remove the lock to the list of currently held locks - this gets
+ * Remove the lock from the list of currently held locks - this gets
  * called on mutex_unlock()/spin_unlock*() (or on a failed
  * mutex_lock_interruptible()).
- *
- * @nested is an hysterical artifact, needs a tree wide cleanup.
  */
 static int
 __lock_release(struct lockdep_map *lock, unsigned long ip)
@@ -4491,8 +4489,7 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 }
 EXPORT_SYMBOL_GPL(lock_acquire);
 
-void lock_release(struct lockdep_map *lock, int nested,
-			  unsigned long ip)
+void lock_release(struct lockdep_map *lock, unsigned long ip)
 {
 	unsigned long flags;
 
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 468a9b8422e3..54cc5f9286e9 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -733,6 +733,9 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne
  */
 void __sched mutex_unlock(struct mutex *lock)
 {
+#ifdef CONFIG_DEBUG_MUTEXES
+	WARN_ON(in_interrupt());
+#endif
 #ifndef CONFIG_DEBUG_LOCK_ALLOC
 	if (__mutex_unlock_fast(lock))
 		return;
@@ -1091,7 +1094,7 @@ err:
 err_early_kill:
 	spin_unlock(&lock->wait_lock);
 	debug_mutex_free_waiter(&waiter);
-	mutex_release(&lock->dep_map, 1, ip);
+	mutex_release(&lock->dep_map, ip);
 	preempt_enable();
 	return ret;
 }
@@ -1225,7 +1228,7 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne
 	DEFINE_WAKE_Q(wake_q);
 	unsigned long owner;
 
-	mutex_release(&lock->dep_map, 1, ip);
+	mutex_release(&lock->dep_map, ip);
 
 	/*
 	 * Release the lock before (potentially) taking the spinlock such that
@@ -1413,6 +1416,7 @@ int __sched mutex_trylock(struct mutex *lock)
 
 #ifdef CONFIG_DEBUG_MUTEXES
 	DEBUG_LOCKS_WARN_ON(lock->magic != lock);
+	WARN_ON(in_interrupt());
 #endif
 
 	locked = __mutex_trylock(lock);
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 2874bf556162..851bbb10819d 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1517,7 +1517,7 @@ int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
 	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_);
+		mutex_release(&lock->dep_map, _RET_IP_);
 
 	return ret;
 }
@@ -1561,7 +1561,7 @@ rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout)
 				       RT_MUTEX_MIN_CHAINWALK,
 				       rt_mutex_slowlock);
 	if (ret)
-		mutex_release(&lock->dep_map, 1, _RET_IP_);
+		mutex_release(&lock->dep_map, _RET_IP_);
 
 	return ret;
 }
@@ -1600,7 +1600,7 @@ EXPORT_SYMBOL_GPL(rt_mutex_trylock);
  */
 void __sched rt_mutex_unlock(struct rt_mutex *lock)
 {
-	mutex_release(&lock->dep_map, 1, _RET_IP_);
+	mutex_release(&lock->dep_map, _RET_IP_);
 	rt_mutex_fastunlock(lock, rt_mutex_slowunlock);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_unlock);
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index eef04551eae7..44e68761f432 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -1504,7 +1504,7 @@ int __sched down_read_killable(struct rw_semaphore *sem)
 	rwsem_acquire_read(&sem->dep_map, 0, 0, _RET_IP_);
 
 	if (LOCK_CONTENDED_RETURN(sem, __down_read_trylock, __down_read_killable)) {
-		rwsem_release(&sem->dep_map, 1, _RET_IP_);
+		rwsem_release(&sem->dep_map, _RET_IP_);
 		return -EINTR;
 	}
 
@@ -1546,7 +1546,7 @@ int __sched down_write_killable(struct rw_semaphore *sem)
 
 	if (LOCK_CONTENDED_RETURN(sem, __down_write_trylock,
 				  __down_write_killable)) {
-		rwsem_release(&sem->dep_map, 1, _RET_IP_);
+		rwsem_release(&sem->dep_map, _RET_IP_);
 		return -EINTR;
 	}
 
@@ -1573,7 +1573,7 @@ EXPORT_SYMBOL(down_write_trylock);
  */
 void up_read(struct rw_semaphore *sem)
 {
-	rwsem_release(&sem->dep_map, 1, _RET_IP_);
+	rwsem_release(&sem->dep_map, _RET_IP_);
 	__up_read(sem);
 }
 EXPORT_SYMBOL(up_read);
@@ -1583,7 +1583,7 @@ EXPORT_SYMBOL(up_read);
  */
 void up_write(struct rw_semaphore *sem)
 {
-	rwsem_release(&sem->dep_map, 1, _RET_IP_);
+	rwsem_release(&sem->dep_map, _RET_IP_);
 	__up_write(sem);
 }
 EXPORT_SYMBOL(up_write);
@@ -1639,7 +1639,7 @@ int __sched down_write_killable_nested(struct rw_semaphore *sem, int subclass)
 
 	if (LOCK_CONTENDED_RETURN(sem, __down_write_trylock,
 				  __down_write_killable)) {
-		rwsem_release(&sem->dep_map, 1, _RET_IP_);
+		rwsem_release(&sem->dep_map, _RET_IP_);
 		return -EINTR;
 	}