|
1 /* |
|
2 * RT Mutexes: blocking mutual exclusion locks with PI support |
|
3 * |
|
4 * started by Ingo Molnar and Thomas Gleixner: |
|
5 * |
|
6 * Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> |
|
7 * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com> |
|
8 * |
|
9 * This file contains the public data structure and API definitions. |
|
10 */ |
|
11 |
|
12 #ifndef __LINUX_RT_MUTEX_H |
|
13 #define __LINUX_RT_MUTEX_H |
|
14 |
|
15 #include <linux/linkage.h> |
|
16 #include <linux/plist.h> |
|
17 #include <linux/spinlock_types.h> |
|
18 |
|
19 /** |
|
20 * The rt_mutex structure |
|
21 * |
|
22 * @wait_lock: spinlock to protect the structure |
|
23 * @wait_list: pilist head to enqueue waiters in priority order |
|
24 * @owner: the mutex owner |
|
25 */ |
|
26 struct rt_mutex { |
|
27 spinlock_t wait_lock; |
|
28 struct plist_head wait_list; |
|
29 struct task_struct *owner; |
|
30 #ifdef CONFIG_DEBUG_RT_MUTEXES |
|
31 int save_state; |
|
32 const char *name, *file; |
|
33 int line; |
|
34 void *magic; |
|
35 #endif |
|
36 }; |
|
37 |
|
38 struct rt_mutex_waiter; |
|
39 struct hrtimer_sleeper; |
|
40 |
|
41 #ifdef CONFIG_DEBUG_RT_MUTEXES |
|
42 extern int rt_mutex_debug_check_no_locks_freed(const void *from, |
|
43 unsigned long len); |
|
44 extern void rt_mutex_debug_check_no_locks_held(struct task_struct *task); |
|
45 #else |
|
46 static inline int rt_mutex_debug_check_no_locks_freed(const void *from, |
|
47 unsigned long len) |
|
48 { |
|
49 return 0; |
|
50 } |
|
51 # define rt_mutex_debug_check_no_locks_held(task) do { } while (0) |
|
52 #endif |
|
53 |
|
54 #ifdef CONFIG_DEBUG_RT_MUTEXES |
|
55 # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \ |
|
56 , .name = #mutexname, .file = __FILE__, .line = __LINE__ |
|
57 # define rt_mutex_init(mutex) __rt_mutex_init(mutex, __func__) |
|
58 extern void rt_mutex_debug_task_free(struct task_struct *tsk); |
|
59 #else |
|
60 # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) |
|
61 # define rt_mutex_init(mutex) __rt_mutex_init(mutex, NULL) |
|
62 # define rt_mutex_debug_task_free(t) do { } while (0) |
|
63 #endif |
|
64 |
|
65 #define __RT_MUTEX_INITIALIZER(mutexname) \ |
|
66 { .wait_lock = __SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \ |
|
67 , .wait_list = PLIST_HEAD_INIT(mutexname.wait_list, mutexname.wait_lock) \ |
|
68 , .owner = NULL \ |
|
69 __DEBUG_RT_MUTEX_INITIALIZER(mutexname)} |
|
70 |
|
71 #define DEFINE_RT_MUTEX(mutexname) \ |
|
72 struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname) |
|
73 |
|
74 /** |
|
75 * rt_mutex_is_locked - is the mutex locked |
|
76 * @lock: the mutex to be queried |
|
77 * |
|
78 * Returns 1 if the mutex is locked, 0 if unlocked. |
|
79 */ |
|
80 static inline int rt_mutex_is_locked(struct rt_mutex *lock) |
|
81 { |
|
82 return lock->owner != NULL; |
|
83 } |
|
84 |
|
85 extern void __rt_mutex_init(struct rt_mutex *lock, const char *name); |
|
86 extern void rt_mutex_destroy(struct rt_mutex *lock); |
|
87 |
|
88 extern void rt_mutex_lock(struct rt_mutex *lock); |
|
89 extern int rt_mutex_lock_interruptible(struct rt_mutex *lock, |
|
90 int detect_deadlock); |
|
91 extern int rt_mutex_timed_lock(struct rt_mutex *lock, |
|
92 struct hrtimer_sleeper *timeout, |
|
93 int detect_deadlock); |
|
94 |
|
95 extern int rt_mutex_trylock(struct rt_mutex *lock); |
|
96 |
|
97 extern void rt_mutex_unlock(struct rt_mutex *lock); |
|
98 |
|
99 #ifdef CONFIG_RT_MUTEXES |
|
100 # define INIT_RT_MUTEXES(tsk) \ |
|
101 .pi_waiters = PLIST_HEAD_INIT(tsk.pi_waiters, tsk.pi_lock), \ |
|
102 INIT_RT_MUTEX_DEBUG(tsk) |
|
103 #else |
|
104 # define INIT_RT_MUTEXES(tsk) |
|
105 #endif |
|
106 |
|
107 #endif |