spinlock_rt.h

  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
 10extern void __rt_spin_lock_init(spinlock_t *lock, const char *name,
 11				struct lock_class_key *key, bool percpu);
 12#else
 13static 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)		\
 20do {								\
 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)				\
 26do {								\
 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
 34extern void rt_spin_lock(spinlock_t *lock) __acquires(lock);
 35extern void rt_spin_lock_nested(spinlock_t *lock, int subclass)	__acquires(lock);
 36extern void rt_spin_lock_nest_lock(spinlock_t *lock, struct lockdep_map *nest_lock) __acquires(lock);
 37extern void rt_spin_unlock(spinlock_t *lock)	__releases(lock);
 38extern void rt_spin_lock_unlock(spinlock_t *lock);
 39extern int rt_spin_trylock_bh(spinlock_t *lock);
 40extern int rt_spin_trylock(spinlock_t *lock);
 41
 42static __always_inline void spin_lock(spinlock_t *lock)
 43{
 44	rt_spin_lock(lock);
 45}
 46
 47#ifdef CONFIG_LOCKDEP
 48# define __spin_lock_nested(lock, subclass)				\
 49	rt_spin_lock_nested(lock, subclass)
 50
 51# define __spin_lock_nest_lock(lock, nest_lock)				\
 52	do {								\
 53		typecheck(struct lockdep_map *, &(nest_lock)->dep_map);	\
 54		rt_spin_lock_nest_lock(lock, &(nest_lock)->dep_map);	\
 55	} while (0)
 56# define __spin_lock_irqsave_nested(lock, flags, subclass)	\
 57	do {							\
 58		typecheck(unsigned long, flags);		\
 59		flags = 0;					\
 60		__spin_lock_nested(lock, subclass);		\
 61	} while (0)
 62
 63#else
 64 /*
 65  * Always evaluate the 'subclass' argument to avoid that the compiler
 66  * warns about set-but-not-used variables when building with
 67  * CONFIG_DEBUG_LOCK_ALLOC=n and with W=1.
 68  */
 69# define __spin_lock_nested(lock, subclass)	spin_lock(((void)(subclass), (lock)))
 70# define __spin_lock_nest_lock(lock, subclass)	spin_lock(((void)(subclass), (lock)))
 71# define __spin_lock_irqsave_nested(lock, flags, subclass)	\
 72	spin_lock_irqsave(((void)(subclass), (lock)), flags)
 73#endif
 74
 75#define spin_lock_nested(lock, subclass)		\
 76	__spin_lock_nested(lock, subclass)
 77
 78#define spin_lock_nest_lock(lock, nest_lock)		\
 79	__spin_lock_nest_lock(lock, nest_lock)
 80
 81#define spin_lock_irqsave_nested(lock, flags, subclass)	\
 82	__spin_lock_irqsave_nested(lock, flags, subclass)
 83
 84static __always_inline void spin_lock_bh(spinlock_t *lock)
 85{
 86	/* Investigate: Drop bh when blocking ? */
 87	local_bh_disable();
 88	rt_spin_lock(lock);
 89}
 90
 91static __always_inline void spin_lock_irq(spinlock_t *lock)
 92{
 93	rt_spin_lock(lock);
 94}
 95
 96#define spin_lock_irqsave(lock, flags)			 \
 97	do {						 \
 98		typecheck(unsigned long, flags);	 \
 99		flags = 0;				 \
100		spin_lock(lock);			 \
101	} while (0)
102
103static __always_inline void spin_unlock(spinlock_t *lock)
104{
105	rt_spin_unlock(lock);
106}
107
108static __always_inline void spin_unlock_bh(spinlock_t *lock)
109{
110	rt_spin_unlock(lock);
111	local_bh_enable();
112}
113
114static __always_inline void spin_unlock_irq(spinlock_t *lock)
115{
116	rt_spin_unlock(lock);
117}
118
119static __always_inline void spin_unlock_irqrestore(spinlock_t *lock,
120						   unsigned long flags)
121{
122	rt_spin_unlock(lock);
123}
124
125#define spin_trylock(lock)				\
126	__cond_lock(lock, rt_spin_trylock(lock))
127
128#define spin_trylock_bh(lock)				\
129	__cond_lock(lock, rt_spin_trylock_bh(lock))
130
131#define spin_trylock_irq(lock)				\
132	__cond_lock(lock, rt_spin_trylock(lock))
133
134#define spin_trylock_irqsave(lock, flags)		\
135({							\
136	int __locked;					\
137							\
138	typecheck(unsigned long, flags);		\
139	flags = 0;					\
140	__locked = spin_trylock(lock);			\
141	__locked;					\
142})
143
144#define spin_is_contended(lock)		(((void)(lock), 0))
145
146static inline int spin_is_locked(spinlock_t *lock)
147{
148	return rt_mutex_base_is_locked(&lock->lock);
149}
150
151#define assert_spin_locked(lock) BUG_ON(!spin_is_locked(lock))
152
153#include <linux/rwlock_rt.h>
154
155#endif