123 lines
3.4 KiB
C
123 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
|