1#ifndef __LINUX_RWLOCK_TYPES_H
2#define __LINUX_RWLOCK_TYPES_H
3
4#if !defined(__LINUX_SPINLOCK_TYPES_H)
5# error "Do not include directly, include spinlock_types.h"
6#endif
7
8#ifdef CONFIG_DEBUG_LOCK_ALLOC
9# define RW_DEP_MAP_INIT(lockname) \
10 .dep_map = { \
11 .name = #lockname, \
12 .wait_type_inner = LD_WAIT_CONFIG, \
13 }
14#else
15# define RW_DEP_MAP_INIT(lockname)
16#endif
17
18#ifndef CONFIG_PREEMPT_RT
19/*
20 * generic rwlock type definitions and initializers
21 *
22 * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
23 * Released under the General Public License (GPL).
24 */
25typedef struct {
26 arch_rwlock_t raw_lock;
27#ifdef CONFIG_DEBUG_SPINLOCK
28 unsigned int magic, owner_cpu;
29 void *owner;
30#endif
31#ifdef CONFIG_DEBUG_LOCK_ALLOC
32 struct lockdep_map dep_map;
33#endif
34} rwlock_t;
35
36#define RWLOCK_MAGIC 0xdeaf1eed
37
38#ifdef CONFIG_DEBUG_SPINLOCK
39#define __RW_LOCK_UNLOCKED(lockname) \
40 (rwlock_t) { .raw_lock = __ARCH_RW_LOCK_UNLOCKED, \
41 .magic = RWLOCK_MAGIC, \
42 .owner = SPINLOCK_OWNER_INIT, \
43 .owner_cpu = -1, \
44 RW_DEP_MAP_INIT(lockname) }
45#else
46#define __RW_LOCK_UNLOCKED(lockname) \
47 (rwlock_t) { .raw_lock = __ARCH_RW_LOCK_UNLOCKED, \
48 RW_DEP_MAP_INIT(lockname) }
49#endif
50
51#define DEFINE_RWLOCK(x) rwlock_t x = __RW_LOCK_UNLOCKED(x)
52
53#else /* !CONFIG_PREEMPT_RT */
54
55#include <linux/rwbase_rt.h>
56
57typedef struct {
58 struct rwbase_rt rwbase;
59 atomic_t readers;
60#ifdef CONFIG_DEBUG_LOCK_ALLOC
61 struct lockdep_map dep_map;
62#endif
63} rwlock_t;
64
65#define __RWLOCK_RT_INITIALIZER(name) \
66{ \
67 .rwbase = __RWBASE_INITIALIZER(name), \
68 RW_DEP_MAP_INIT(name) \
69}
70
71#define __RW_LOCK_UNLOCKED(name) __RWLOCK_RT_INITIALIZER(name)
72
73#define DEFINE_RWLOCK(name) \
74 rwlock_t name = __RW_LOCK_UNLOCKED(name)
75
76#endif /* CONFIG_PREEMPT_RT */
77
78#endif /* __LINUX_RWLOCK_TYPES_H */
79

source code of linux/include/linux/rwlock_types.h