xref: /linux/include/linux/spinlock_rt.h (revision ae22a94997b8a03dcb3c922857c203246711f9d4)
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)					\
20 do {								\
21 	static struct lock_class_key __key;			\
22 								\
23 	rt_mutex_base_init(&(slock)->lock);			\
24 	__rt_spin_lock_init(slock, #slock, &__key, false);	\
25 } while (0)
26 
27 #define local_spin_lock_init(slock)				\
28 do {								\
29 	static struct lock_class_key __key;			\
30 								\
31 	rt_mutex_base_init(&(slock)->lock);			\
32 	__rt_spin_lock_init(slock, #slock, &__key, true);	\
33 } while (0)
34 
35 extern void rt_spin_lock(spinlock_t *lock);
36 extern void rt_spin_lock_nested(spinlock_t *lock, int subclass);
37 extern void rt_spin_lock_nest_lock(spinlock_t *lock, struct lockdep_map *nest_lock);
38 extern void rt_spin_unlock(spinlock_t *lock);
39 extern void rt_spin_lock_unlock(spinlock_t *lock);
40 extern int rt_spin_trylock_bh(spinlock_t *lock);
41 extern int rt_spin_trylock(spinlock_t *lock);
42 
43 static __always_inline void spin_lock(spinlock_t *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 {
87 	/* Investigate: Drop bh when blocking ? */
88 	local_bh_disable();
89 	rt_spin_lock(lock);
90 }
91 
92 static __always_inline void spin_lock_irq(spinlock_t *lock)
93 {
94 	rt_spin_lock(lock);
95 }
96 
97 #define spin_lock_irqsave(lock, flags)			 \
98 	do {						 \
99 		typecheck(unsigned long, flags);	 \
100 		flags = 0;				 \
101 		spin_lock(lock);			 \
102 	} while (0)
103 
104 static __always_inline void spin_unlock(spinlock_t *lock)
105 {
106 	rt_spin_unlock(lock);
107 }
108 
109 static __always_inline void spin_unlock_bh(spinlock_t *lock)
110 {
111 	rt_spin_unlock(lock);
112 	local_bh_enable();
113 }
114 
115 static __always_inline void spin_unlock_irq(spinlock_t *lock)
116 {
117 	rt_spin_unlock(lock);
118 }
119 
120 static __always_inline void spin_unlock_irqrestore(spinlock_t *lock,
121 						   unsigned long flags)
122 {
123 	rt_spin_unlock(lock);
124 }
125 
126 #define spin_trylock(lock)				\
127 	__cond_lock(lock, rt_spin_trylock(lock))
128 
129 #define spin_trylock_bh(lock)				\
130 	__cond_lock(lock, rt_spin_trylock_bh(lock))
131 
132 #define spin_trylock_irq(lock)				\
133 	__cond_lock(lock, rt_spin_trylock(lock))
134 
135 #define __spin_trylock_irqsave(lock, flags)		\
136 ({							\
137 	int __locked;					\
138 							\
139 	typecheck(unsigned long, flags);		\
140 	flags = 0;					\
141 	__locked = spin_trylock(lock);			\
142 	__locked;					\
143 })
144 
145 #define spin_trylock_irqsave(lock, flags)		\
146 	__cond_lock(lock, __spin_trylock_irqsave(lock, flags))
147 
148 #define spin_is_contended(lock)		(((void)(lock), 0))
149 
150 static inline int spin_is_locked(spinlock_t *lock)
151 {
152 	return rt_mutex_base_is_locked(&lock->lock);
153 }
154 
155 #define assert_spin_locked(lock) BUG_ON(!spin_is_locked(lock))
156 
157 #include <linux/rwlock_rt.h>
158 
159 #endif
160