1 files changed, 57 insertions, 17 deletions

diff --git a/kernel/locking/rtmutex_api.c b/kernel/locking/rtmutex_api.c
index 191e4720e546..514fce7a4e0a 100644
--- a/kernel/locking/rtmutex_api.c
+++ b/kernel/locking/rtmutex_api.c
@@ -13,6 +13,24 @@
  */
 int max_lock_depth = 1024;
 
+static const struct ctl_table rtmutex_sysctl_table[] = {
+	{
+		.procname	= "max_lock_depth",
+		.data		= &max_lock_depth,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+};
+
+static int __init init_rtmutex_sysctl(void)
+{
+	register_sysctl_init("kernel", rtmutex_sysctl_table);
+	return 0;
+}
+
+subsys_initcall(init_rtmutex_sysctl);
+
 /*
  * Debug aware fast / slowpath lock,trylock,unlock
  *
@@ -347,7 +365,7 @@ int __sched rt_mutex_start_proxy_lock(struct rt_mutex_base *lock,
 
 	raw_spin_lock_irq(&lock->wait_lock);
 	ret = __rt_mutex_start_proxy_lock(lock, waiter, task, &wake_q);
-	if (unlikely(ret))
+	if (unlikely(ret < 0))
 		remove_waiter(lock, waiter);
 	preempt_disable();
 	raw_spin_unlock_irq(&lock->wait_lock);
@@ -497,19 +515,18 @@ void rt_mutex_debug_task_free(struct task_struct *task)
 
 #ifdef CONFIG_PREEMPT_RT
 /* Mutexes */
-void __mutex_rt_init(struct mutex *mutex, const char *name,
-		     struct lock_class_key *key)
+static void __mutex_rt_init_generic(struct mutex *mutex)
 {
+	rt_mutex_base_init(&mutex->rtmutex);
 	debug_check_no_locks_freed((void *)mutex, sizeof(*mutex));
-	lockdep_init_map_wait(&mutex->dep_map, name, key, 0, LD_WAIT_SLEEP);
 }
-EXPORT_SYMBOL(__mutex_rt_init);
 
 static __always_inline int __mutex_lock_common(struct mutex *lock,
 					       unsigned int state,
 					       unsigned int subclass,
 					       struct lockdep_map *nest_lock,
 					       unsigned long ip)
+	__acquires(lock) __no_context_analysis
 {
 	int ret;
 
@@ -524,6 +541,13 @@ static __always_inline int __mutex_lock_common(struct mutex *lock,
 }
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
+void mutex_rt_init_lockdep(struct mutex *mutex, const char *name, struct lock_class_key *key)
+{
+	__mutex_rt_init_generic(mutex);
+	lockdep_init_map_wait(&mutex->dep_map, name, key, 0, LD_WAIT_SLEEP);
+}
+EXPORT_SYMBOL(mutex_rt_init_lockdep);
+
 void __sched mutex_lock_nested(struct mutex *lock, unsigned int subclass)
 {
 	__mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, subclass, NULL, _RET_IP_);
@@ -544,12 +568,12 @@ int __sched mutex_lock_interruptible_nested(struct mutex *lock,
 }
 EXPORT_SYMBOL_GPL(mutex_lock_interruptible_nested);
 
-int __sched mutex_lock_killable_nested(struct mutex *lock,
-					    unsigned int subclass)
+int __sched _mutex_lock_killable(struct mutex *lock, unsigned int subclass,
+				 struct lockdep_map *nest_lock)
 {
-	return __mutex_lock_common(lock, TASK_KILLABLE, subclass, NULL, _RET_IP_);
+	return __mutex_lock_common(lock, TASK_KILLABLE, subclass, nest_lock, _RET_IP_);
 }
-EXPORT_SYMBOL_GPL(mutex_lock_killable_nested);
+EXPORT_SYMBOL_GPL(_mutex_lock_killable);
 
 void __sched mutex_lock_io_nested(struct mutex *lock, unsigned int subclass)
 {
@@ -563,8 +587,29 @@ void __sched mutex_lock_io_nested(struct mutex *lock, unsigned int subclass)
 }
 EXPORT_SYMBOL_GPL(mutex_lock_io_nested);
 
+int __sched _mutex_trylock_nest_lock(struct mutex *lock,
+				     struct lockdep_map *nest_lock)
+{
+	int ret;
+
+	if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task()))
+		return 0;
+
+	ret = __rt_mutex_trylock(&lock->rtmutex);
+	if (ret)
+		mutex_acquire_nest(&lock->dep_map, 0, 1, nest_lock, _RET_IP_);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(_mutex_trylock_nest_lock);
 #else /* CONFIG_DEBUG_LOCK_ALLOC */
 
+void mutex_rt_init_generic(struct mutex *mutex)
+{
+	__mutex_rt_init_generic(mutex);
+}
+EXPORT_SYMBOL(mutex_rt_init_generic);
+
 void __sched mutex_lock(struct mutex *lock)
 {
 	__mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, 0, NULL, _RET_IP_);
@@ -591,24 +636,19 @@ void __sched mutex_lock_io(struct mutex *lock)
 	io_schedule_finish(token);
 }
 EXPORT_SYMBOL(mutex_lock_io);
-#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
 
 int __sched mutex_trylock(struct mutex *lock)
 {
-	int ret;
-
 	if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task()))
 		return 0;
 
-	ret = __rt_mutex_trylock(&lock->rtmutex);
-	if (ret)
-		mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
-
-	return ret;
+	return __rt_mutex_trylock(&lock->rtmutex);
 }
 EXPORT_SYMBOL(mutex_trylock);
+#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
 
 void __sched mutex_unlock(struct mutex *lock)
+	__releases(lock) __no_context_analysis
 {
 	mutex_release(&lock->dep_map, _RET_IP_);
 	__rt_mutex_unlock(&lock->rtmutex);