1 /* SPDX-License-Identifier: GPL-2.0 */ 1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* 2 /*
3 * RT Mutexes: blocking mutual exclusion locks 3 * RT Mutexes: blocking mutual exclusion locks with PI support
4 * 4 *
5 * started by Ingo Molnar and Thomas Gleixner: 5 * started by Ingo Molnar and Thomas Gleixner:
6 * 6 *
7 * Copyright (C) 2004-2006 Red Hat, Inc., Ing 7 * Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
8 * Copyright (C) 2006, Timesys Corp., Thomas 8 * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
9 * 9 *
10 * This file contains the public data structur 10 * This file contains the public data structure and API definitions.
11 */ 11 */
12 12
13 #ifndef __LINUX_RT_MUTEX_H 13 #ifndef __LINUX_RT_MUTEX_H
14 #define __LINUX_RT_MUTEX_H 14 #define __LINUX_RT_MUTEX_H
15 15
16 #include <linux/compiler.h> 16 #include <linux/compiler.h>
17 #include <linux/linkage.h> 17 #include <linux/linkage.h>
18 #include <linux/rbtree_types.h> 18 #include <linux/rbtree_types.h>
19 #include <linux/spinlock_types_raw.h> 19 #include <linux/spinlock_types_raw.h>
20 20
21 extern int max_lock_depth; /* for sysctl */ 21 extern int max_lock_depth; /* for sysctl */
22 22
23 struct rt_mutex_base { 23 struct rt_mutex_base {
24 raw_spinlock_t wait_lock; 24 raw_spinlock_t wait_lock;
25 struct rb_root_cached waiters; 25 struct rb_root_cached waiters;
26 struct task_struct *owner; 26 struct task_struct *owner;
27 }; 27 };
28 28
29 #define __RT_MUTEX_BASE_INITIALIZER(rtbasename 29 #define __RT_MUTEX_BASE_INITIALIZER(rtbasename) \
30 { 30 { \
31 .wait_lock = __RAW_SPIN_LOCK_UNLOCKED( 31 .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(rtbasename.wait_lock), \
32 .waiters = RB_ROOT_CACHED, 32 .waiters = RB_ROOT_CACHED, \
33 .owner = NULL 33 .owner = NULL \
34 } 34 }
35 35
36 /** 36 /**
37 * rt_mutex_base_is_locked - is the rtmutex lo 37 * rt_mutex_base_is_locked - is the rtmutex locked
38 * @lock: the mutex to be queried 38 * @lock: the mutex to be queried
39 * 39 *
40 * Returns true if the mutex is locked, false 40 * Returns true if the mutex is locked, false if unlocked.
41 */ 41 */
42 static inline bool rt_mutex_base_is_locked(str 42 static inline bool rt_mutex_base_is_locked(struct rt_mutex_base *lock)
43 { 43 {
44 return READ_ONCE(lock->owner) != NULL; 44 return READ_ONCE(lock->owner) != NULL;
45 } 45 }
46 46
47 extern void rt_mutex_base_init(struct rt_mutex 47 extern void rt_mutex_base_init(struct rt_mutex_base *rtb);
48 48
49 /** 49 /**
50 * The rt_mutex structure 50 * The rt_mutex structure
51 * 51 *
52 * @wait_lock: spinlock to protect the struct 52 * @wait_lock: spinlock to protect the structure
53 * @waiters: rbtree root to enqueue waiters 53 * @waiters: rbtree root to enqueue waiters in priority order;
54 * caches top-waiter (leftmost no 54 * caches top-waiter (leftmost node).
55 * @owner: the mutex owner 55 * @owner: the mutex owner
56 */ 56 */
57 struct rt_mutex { 57 struct rt_mutex {
58 struct rt_mutex_base rtmutex; 58 struct rt_mutex_base rtmutex;
59 #ifdef CONFIG_DEBUG_LOCK_ALLOC 59 #ifdef CONFIG_DEBUG_LOCK_ALLOC
60 struct lockdep_map dep_map; 60 struct lockdep_map dep_map;
61 #endif 61 #endif
62 }; 62 };
63 63
64 struct rt_mutex_waiter; 64 struct rt_mutex_waiter;
65 struct hrtimer_sleeper; 65 struct hrtimer_sleeper;
66 66
67 #ifdef CONFIG_DEBUG_RT_MUTEXES 67 #ifdef CONFIG_DEBUG_RT_MUTEXES
68 extern void rt_mutex_debug_task_free(struct ta 68 extern void rt_mutex_debug_task_free(struct task_struct *tsk);
69 #else 69 #else
70 static inline void rt_mutex_debug_task_free(st 70 static inline void rt_mutex_debug_task_free(struct task_struct *tsk) { }
71 #endif 71 #endif
72 72
73 #define rt_mutex_init(mutex) \ 73 #define rt_mutex_init(mutex) \
74 do { \ 74 do { \
75 static struct lock_class_key __key; \ 75 static struct lock_class_key __key; \
76 __rt_mutex_init(mutex, __func__, &__ke 76 __rt_mutex_init(mutex, __func__, &__key); \
77 } while (0) 77 } while (0)
78 78
79 #ifdef CONFIG_DEBUG_LOCK_ALLOC 79 #ifdef CONFIG_DEBUG_LOCK_ALLOC
80 #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexna 80 #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) \
81 .dep_map = { 81 .dep_map = { \
82 .name = #mutexname, 82 .name = #mutexname, \
83 .wait_type_inner = LD_WAIT_SLE 83 .wait_type_inner = LD_WAIT_SLEEP, \
84 } 84 }
85 #else 85 #else
86 #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexna 86 #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
87 #endif 87 #endif
88 88
89 #define __RT_MUTEX_INITIALIZER(mutexname) 89 #define __RT_MUTEX_INITIALIZER(mutexname) \
90 { 90 { \
91 .rtmutex = __RT_MUTEX_BASE_INITIALIZER 91 .rtmutex = __RT_MUTEX_BASE_INITIALIZER(mutexname.rtmutex), \
92 __DEP_MAP_RT_MUTEX_INITIALIZER(mutexna 92 __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) \
93 } 93 }
94 94
95 #define DEFINE_RT_MUTEX(mutexname) \ 95 #define DEFINE_RT_MUTEX(mutexname) \
96 struct rt_mutex mutexname = __RT_MUTEX 96 struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname)
97 97
98 extern void __rt_mutex_init(struct rt_mutex *l 98 extern void __rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key);
99 99
100 #ifdef CONFIG_DEBUG_LOCK_ALLOC 100 #ifdef CONFIG_DEBUG_LOCK_ALLOC
101 extern void rt_mutex_lock_nested(struct rt_mut 101 extern void rt_mutex_lock_nested(struct rt_mutex *lock, unsigned int subclass);
102 extern void _rt_mutex_lock_nest_lock(struct rt 102 extern void _rt_mutex_lock_nest_lock(struct rt_mutex *lock, struct lockdep_map *nest_lock);
103 #define rt_mutex_lock(lock) rt_mutex_lock_nest 103 #define rt_mutex_lock(lock) rt_mutex_lock_nested(lock, 0)
104 #define rt_mutex_lock_nest_lock(lock, nest_loc 104 #define rt_mutex_lock_nest_lock(lock, nest_lock) \
105 do { 105 do { \
106 typecheck(struct lockdep_map * 106 typecheck(struct lockdep_map *, &(nest_lock)->dep_map); \
107 _rt_mutex_lock_nest_lock(lock, 107 _rt_mutex_lock_nest_lock(lock, &(nest_lock)->dep_map); \
108 } while (0) 108 } while (0)
109 109
110 #else 110 #else
111 extern void rt_mutex_lock(struct rt_mutex *loc 111 extern void rt_mutex_lock(struct rt_mutex *lock);
112 #define rt_mutex_lock_nested(lock, subclass) r 112 #define rt_mutex_lock_nested(lock, subclass) rt_mutex_lock(lock)
113 #define rt_mutex_lock_nest_lock(lock, nest_loc 113 #define rt_mutex_lock_nest_lock(lock, nest_lock) rt_mutex_lock(lock)
114 #endif 114 #endif
115 115
116 extern int rt_mutex_lock_interruptible(struct 116 extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
117 extern int rt_mutex_lock_killable(struct rt_mu 117 extern int rt_mutex_lock_killable(struct rt_mutex *lock);
118 extern int rt_mutex_trylock(struct rt_mutex *l 118 extern int rt_mutex_trylock(struct rt_mutex *lock);
119 119
120 extern void rt_mutex_unlock(struct rt_mutex *l 120 extern void rt_mutex_unlock(struct rt_mutex *lock);
121 121
122 #endif 122 #endif
123 123
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