xref: /linux/include/linux/spinlock_rt.h (revision c36a4991e231242c04141536718d47255ec80887)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #ifndef __LINUX_SPINLOCK_RT_H
3 #define __LINUX_SPINLOCK_RT_H
4 
5 #ifndef __LINUX_INSIDE_SPINLOCK_H
6 #error Do not include directly. Use spinlock.h
7 #endif
8 
9 #ifdef CONFIG_DEBUG_LOCK_ALLOC
10 extern void __rt_spin_lock_init(spinlock_t *lock, const char *name,
11 				struct lock_class_key *key, bool percpu);
12 #else
13 static inline void __rt_spin_lock_init(spinlock_t *lock, const char *name,
14 				struct lock_class_key *key, bool percpu)
15 {
16 }
17 #endif
18 
19 #define __spin_lock_init(slock, name, key, percpu)		\
20 do {								\
21 	rt_mutex_base_init(&(slock)->lock);			\
22 	__rt_spin_lock_init(slock, name, key, percpu);		\
23 } while (0)
24 
25 #define _spin_lock_init(slock, percpu)				\
26 do {								\
27 	static struct lock_class_key __key;			\
28 	__spin_lock_init(slock, #slock, &__key, percpu);	\
29 } while (0)
30 
31 #define spin_lock_init(slock)		_spin_lock_init(slock, false)
32 #define local_spin_lock_init(slock)	_spin_lock_init(slock, true)
33 
34 extern void rt_spin_lock(spinlock_t *lock) __acquires(lock);
35 extern void rt_spin_lock_nested(spinlock_t *lock, int subclass)	__acquires(lock);
36 extern void rt_spin_lock_nest_lock(spinlock_t *lock, struct lockdep_map *nest_lock) __acquires(lock);
37 extern void rt_spin_unlock(spinlock_t *lock)	__releases(lock);
38 extern void rt_spin_lock_unlock(spinlock_t *lock);
39 extern int rt_spin_trylock_bh(spinlock_t *lock) __cond_acquires(true, lock);
40 extern int rt_spin_trylock(spinlock_t *lock) __cond_acquires(true, lock);
41 
42 static __always_inline void spin_lock(spinlock_t *lock)
43 	__acquires(lock)
44 {
45 	rt_spin_lock(lock);
46 }
47 
48 #ifdef CONFIG_LOCKDEP
49 # define __spin_lock_nested(lock, subclass)				\
50 	rt_spin_lock_nested(lock, subclass)
51 
52 # define __spin_lock_nest_lock(lock, nest_lock)				\
53 	do {								\
54 		typecheck(struct lockdep_map *, &(nest_lock)->dep_map);	\
55 		rt_spin_lock_nest_lock(lock, &(nest_lock)->dep_map);	\
56 	} while (0)
57 # define __spin_lock_irqsave_nested(lock, flags, subclass)	\
58 	do {							\
59 		typecheck(unsigned long, flags);		\
60 		flags = 0;					\
61 		__spin_lock_nested(lock, subclass);		\
62 	} while (0)
63 
64 #else
65  /*
66   * Always evaluate the 'subclass' argument to avoid that the compiler
67   * warns about set-but-not-used variables when building with
68   * CONFIG_DEBUG_LOCK_ALLOC=n and with W=1.
69   */
70 # define __spin_lock_nested(lock, subclass)	spin_lock(((void)(subclass), (lock)))
71 # define __spin_lock_nest_lock(lock, subclass)	spin_lock(((void)(subclass), (lock)))
72 # define __spin_lock_irqsave_nested(lock, flags, subclass)	\
73 	spin_lock_irqsave(((void)(subclass), (lock)), flags)
74 #endif
75 
76 #define spin_lock_nested(lock, subclass)		\
77 	__spin_lock_nested(lock, subclass)
78 
79 #define spin_lock_nest_lock(lock, nest_lock)		\
80 	__spin_lock_nest_lock(lock, nest_lock)
81 
82 #define spin_lock_irqsave_nested(lock, flags, subclass)	\
83 	__spin_lock_irqsave_nested(lock, flags, subclass)
84 
85 static __always_inline void spin_lock_bh(spinlock_t *lock)
86 	__acquires(lock)
87 {
88 	/* Investigate: Drop bh when blocking ? */
89 	local_bh_disable();
90 	rt_spin_lock(lock);
91 }
92 
93 static __always_inline void spin_lock_irq(spinlock_t *lock)
94 	__acquires(lock)
95 {
96 	rt_spin_lock(lock);
97 }
98 
99 static __always_inline void spin_lock_irq_disable(spinlock_t *lock)
100 	__acquires(lock)
101 {
102 	rt_spin_lock(lock);
103 }
104 
105 #define spin_lock_irqsave(lock, flags)			 \
106 	do {						 \
107 		typecheck(unsigned long, flags);	 \
108 		flags = 0;				 \
109 		spin_lock(lock);			 \
110 	} while (0)
111 
112 static __always_inline void spin_unlock(spinlock_t *lock)
113 	__releases(lock)
114 {
115 	rt_spin_unlock(lock);
116 }
117 
118 static __always_inline void spin_unlock_bh(spinlock_t *lock)
119 	__releases(lock)
120 {
121 	rt_spin_unlock(lock);
122 	local_bh_enable();
123 }
124 
125 static __always_inline void spin_unlock_irq(spinlock_t *lock)
126 	__releases(lock)
127 {
128 	rt_spin_unlock(lock);
129 }
130 
131 static __always_inline void spin_unlock_irq_enable(spinlock_t *lock)
132 	__releases(lock)
133 {
134 	rt_spin_unlock(lock);
135 }
136 
137 static __always_inline void spin_unlock_irqrestore(spinlock_t *lock,
138 						   unsigned long flags)
139 	__releases(lock)
140 {
141 	rt_spin_unlock(lock);
142 }
143 
144 #define spin_trylock(lock)	rt_spin_trylock(lock)
145 
146 static __always_inline int spin_trylock_irq_disable(spinlock_t *lock)
147 	__cond_acquires(true, lock)
148 {
149 	return rt_spin_trylock(lock);
150 }
151 
152 #define spin_trylock_bh(lock)	rt_spin_trylock_bh(lock)
153 
154 #define spin_trylock_irq(lock)	rt_spin_trylock(lock)
155 
156 static __always_inline bool _spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags)
157 	__cond_acquires(true, lock)
158 {
159 	*flags = 0;
160 	return rt_spin_trylock(lock);
161 }
162 #define spin_trylock_irqsave(lock, flags) _spin_trylock_irqsave(lock, &(flags))
163 
164 #define spin_is_contended(lock)		(((void)(lock), 0))
165 
166 static inline int spin_is_locked(spinlock_t *lock)
167 {
168 	return rt_mutex_base_is_locked(&lock->lock);
169 }
170 
171 #define assert_spin_locked(lock) BUG_ON(!spin_is_locked(lock))
172 
173 #include <linux/rwlock_rt.h>
174 
175 #endif
176