forked from mirrors/linux
		
	The locking selftest for ww-mutex expects to operate directly on the base-mutex which becomes a rtmutex on PREEMPT_RT. Add a rtmutex based implementation of mutex_lock_nest_lock() and mutex_lock_killable() named rt_mutex_lock_nest_lock() abd rt_mutex_lock_killable(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20211129174654.668506-5-bigeasy@linutronix.de
		
			
				
	
	
		
			122 lines
		
	
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			122 lines
		
	
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0 */
 | 
						|
/*
 | 
						|
 * RT Mutexes: blocking mutual exclusion locks with PI support
 | 
						|
 *
 | 
						|
 * started by Ingo Molnar and Thomas Gleixner:
 | 
						|
 *
 | 
						|
 *  Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
 | 
						|
 *  Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
 | 
						|
 *
 | 
						|
 * This file contains the public data structure and API definitions.
 | 
						|
 */
 | 
						|
 | 
						|
#ifndef __LINUX_RT_MUTEX_H
 | 
						|
#define __LINUX_RT_MUTEX_H
 | 
						|
 | 
						|
#include <linux/compiler.h>
 | 
						|
#include <linux/linkage.h>
 | 
						|
#include <linux/rbtree_types.h>
 | 
						|
#include <linux/spinlock_types_raw.h>
 | 
						|
 | 
						|
extern int max_lock_depth; /* for sysctl */
 | 
						|
 | 
						|
struct rt_mutex_base {
 | 
						|
	raw_spinlock_t		wait_lock;
 | 
						|
	struct rb_root_cached   waiters;
 | 
						|
	struct task_struct	*owner;
 | 
						|
};
 | 
						|
 | 
						|
#define __RT_MUTEX_BASE_INITIALIZER(rtbasename)				\
 | 
						|
{									\
 | 
						|
	.wait_lock = __RAW_SPIN_LOCK_UNLOCKED(rtbasename.wait_lock),	\
 | 
						|
	.waiters = RB_ROOT_CACHED,					\
 | 
						|
	.owner = NULL							\
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * rt_mutex_base_is_locked - is the rtmutex locked
 | 
						|
 * @lock: the mutex to be queried
 | 
						|
 *
 | 
						|
 * Returns true if the mutex is locked, false if unlocked.
 | 
						|
 */
 | 
						|
static inline bool rt_mutex_base_is_locked(struct rt_mutex_base *lock)
 | 
						|
{
 | 
						|
	return READ_ONCE(lock->owner) != NULL;
 | 
						|
}
 | 
						|
 | 
						|
extern void rt_mutex_base_init(struct rt_mutex_base *rtb);
 | 
						|
 | 
						|
/**
 | 
						|
 * The rt_mutex structure
 | 
						|
 *
 | 
						|
 * @wait_lock:	spinlock to protect the structure
 | 
						|
 * @waiters:	rbtree root to enqueue waiters in priority order;
 | 
						|
 *              caches top-waiter (leftmost node).
 | 
						|
 * @owner:	the mutex owner
 | 
						|
 */
 | 
						|
struct rt_mutex {
 | 
						|
	struct rt_mutex_base	rtmutex;
 | 
						|
#ifdef CONFIG_DEBUG_LOCK_ALLOC
 | 
						|
	struct lockdep_map	dep_map;
 | 
						|
#endif
 | 
						|
};
 | 
						|
 | 
						|
struct rt_mutex_waiter;
 | 
						|
struct hrtimer_sleeper;
 | 
						|
 | 
						|
#ifdef CONFIG_DEBUG_RT_MUTEXES
 | 
						|
extern void rt_mutex_debug_task_free(struct task_struct *tsk);
 | 
						|
#else
 | 
						|
static inline void rt_mutex_debug_task_free(struct task_struct *tsk) { }
 | 
						|
#endif
 | 
						|
 | 
						|
#define rt_mutex_init(mutex) \
 | 
						|
do { \
 | 
						|
	static struct lock_class_key __key; \
 | 
						|
	__rt_mutex_init(mutex, __func__, &__key); \
 | 
						|
} while (0)
 | 
						|
 | 
						|
#ifdef CONFIG_DEBUG_LOCK_ALLOC
 | 
						|
#define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)	\
 | 
						|
	.dep_map = {					\
 | 
						|
		.name = #mutexname,			\
 | 
						|
		.wait_type_inner = LD_WAIT_SLEEP,	\
 | 
						|
	}
 | 
						|
#else
 | 
						|
#define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
 | 
						|
#endif
 | 
						|
 | 
						|
#define __RT_MUTEX_INITIALIZER(mutexname)				\
 | 
						|
{									\
 | 
						|
	.rtmutex = __RT_MUTEX_BASE_INITIALIZER(mutexname.rtmutex),	\
 | 
						|
	__DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)			\
 | 
						|
}
 | 
						|
 | 
						|
#define DEFINE_RT_MUTEX(mutexname) \
 | 
						|
	struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname)
 | 
						|
 | 
						|
extern void __rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key);
 | 
						|
 | 
						|
#ifdef CONFIG_DEBUG_LOCK_ALLOC
 | 
						|
extern void rt_mutex_lock_nested(struct rt_mutex *lock, unsigned int subclass);
 | 
						|
extern void _rt_mutex_lock_nest_lock(struct rt_mutex *lock, struct lockdep_map *nest_lock);
 | 
						|
#define rt_mutex_lock(lock) rt_mutex_lock_nested(lock, 0)
 | 
						|
#define rt_mutex_lock_nest_lock(lock, nest_lock)			\
 | 
						|
	do {								\
 | 
						|
		typecheck(struct lockdep_map *, &(nest_lock)->dep_map);	\
 | 
						|
		_rt_mutex_lock_nest_lock(lock, &(nest_lock)->dep_map);	\
 | 
						|
	} while (0)
 | 
						|
 | 
						|
#else
 | 
						|
extern void rt_mutex_lock(struct rt_mutex *lock);
 | 
						|
#define rt_mutex_lock_nested(lock, subclass) rt_mutex_lock(lock)
 | 
						|
#define rt_mutex_lock_nest_lock(lock, nest_lock) rt_mutex_lock(lock)
 | 
						|
#endif
 | 
						|
 | 
						|
extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
 | 
						|
extern int rt_mutex_lock_killable(struct rt_mutex *lock);
 | 
						|
extern int rt_mutex_trylock(struct rt_mutex *lock);
 | 
						|
 | 
						|
extern void rt_mutex_unlock(struct rt_mutex *lock);
 | 
						|
 | 
						|
#endif
 |