1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
/*
* Mutexes: blocking mutual exclusion locks
*
* started by Ingo Molnar:
*
* Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
*
* This file contains the main data structure and API definitions.
*/
#ifndef __LINUX_MUTEX_H
#define __LINUX_MUTEX_H
#include <linux/list.h>
#include <linux/spinlock_types.h>
#include <linux/linkage.h>
#include <linux/lockdep.h>
#include <linux/atomic.h>
struct mutex {
atomic_t count;
spinlock_t wait_lock;
struct list_head wait_list;
#if defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_SMP)
struct task_struct *owner;
#endif
#ifdef CONFIG_DEBUG_MUTEXES
const char *name;
void *magic;
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
#endif
};
struct mutex_waiter {
struct list_head list;
struct task_struct *task;
#ifdef CONFIG_DEBUG_MUTEXES
void *magic;
#endif
};
#ifdef CONFIG_DEBUG_MUTEXES
# include <linux/mutex-debug.h>
#else
# define __DEBUG_MUTEX_INITIALIZER(lockname)
# define mutex_init(mutex) \
do { \
static struct lock_class_key __key; \
\
__mutex_init((mutex), #mutex, &__key); \
} while (0)
static inline void mutex_destroy(struct mutex *lock) {}
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
, .dep_map = { .name = #lockname }
#else
# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
#endif
#define __MUTEX_INITIALIZER(lockname) \
{ .count = ATOMIC_INIT(1) \
, .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
, .wait_list = LIST_HEAD_INIT(lockname.wait_list) \
__DEBUG_MUTEX_INITIALIZER(lockname) \
__DEP_MAP_MUTEX_INITIALIZER(lockname) }
#define DEFINE_MUTEX(mutexname) \
struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
extern void __mutex_init(struct mutex *lock, const char *name,
struct lock_class_key *key);
static inline int mutex_is_locked(struct mutex *lock)
{
return atomic_read(&lock->count) != 1;
}
#ifdef CONFIG_DEBUG_LOCK_ALLOC
extern void mutex_lock_nested(struct mutex *lock, unsigned int subclass);
extern void _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock);
extern int __must_check mutex_lock_interruptible_nested(struct mutex *lock,
unsigned int subclass);
extern int __must_check mutex_lock_killable_nested(struct mutex *lock,
unsigned int subclass);
#define mutex_lock(lock) mutex_lock_nested(lock, 0)
#define mutex_lock_interruptible(lock) mutex_lock_interruptible_nested(lock, 0)
#define mutex_lock_killable(lock) mutex_lock_killable_nested(lock, 0)
#define mutex_lock_nest_lock(lock, nest_lock) \
do { \
typecheck(struct lockdep_map *, &(nest_lock)->dep_map); \
_mutex_lock_nest_lock(lock, &(nest_lock)->dep_map); \
} while (0)
#else
extern void mutex_lock(struct mutex *lock);
extern int __must_check mutex_lock_interruptible(struct mutex *lock);
extern int __must_check mutex_lock_killable(struct mutex *lock);
# define mutex_lock_nested(lock, subclass) mutex_lock(lock)
# define mutex_lock_interruptible_nested(lock, subclass) mutex_lock_interruptible(lock)
# define mutex_lock_killable_nested(lock, subclass) mutex_lock_killable(lock)
# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock)
#endif
extern int mutex_trylock(struct mutex *lock);
extern void mutex_unlock(struct mutex *lock);
extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
#ifndef CONFIG_HAVE_ARCH_MUTEX_CPU_RELAX
#define arch_mutex_cpu_relax() cpu_relax()
#endif
#endif
|
