1#ifndef __LINUX_RWLOCK_H 2#define __LINUX_RWLOCK_H 3 4#ifndef __LINUX_SPINLOCK_H 5# error "please don't include this file directly" 6#endif 7 8/* 9 * rwlock related methods 10 * 11 * split out from spinlock.h 12 * 13 * portions Copyright 2005, Red Hat, Inc., Ingo Molnar 14 * Released under the General Public License (GPL). 15 */ 16 17#ifdef CONFIG_DEBUG_SPINLOCK 18 extern void __rwlock_init(rwlock_t *lock, const char *name, 19 struct lock_class_key *key); 20# define rwlock_init(lock) \ 21do { \ 22 static struct lock_class_key __key; \ 23 \ 24 __rwlock_init((lock), #lock, &__key); \ 25} while (0) 26#else 27# define rwlock_init(lock) \ 28 do { *(lock) = __RW_LOCK_UNLOCKED(lock); } while (0) 29#endif 30 31#ifdef CONFIG_DEBUG_SPINLOCK 32 extern void do_raw_read_lock(rwlock_t *lock) __acquires(lock); 33#define do_raw_read_lock_flags(lock, flags) do_raw_read_lock(lock) 34 extern int do_raw_read_trylock(rwlock_t *lock); 35 extern void do_raw_read_unlock(rwlock_t *lock) __releases(lock); 36 extern void do_raw_write_lock(rwlock_t *lock) __acquires(lock); 37#define do_raw_write_lock_flags(lock, flags) do_raw_write_lock(lock) 38 extern int do_raw_write_trylock(rwlock_t *lock); 39 extern void do_raw_write_unlock(rwlock_t *lock) __releases(lock); 40#else 41# define do_raw_read_lock(rwlock) do {__acquire(lock); arch_read_lock(&(rwlock)->raw_lock); } while (0) 42# define do_raw_read_lock_flags(lock, flags) \ 43 do {__acquire(lock); arch_read_lock_flags(&(lock)->raw_lock, *(flags)); } while (0) 44# define do_raw_read_trylock(rwlock) arch_read_trylock(&(rwlock)->raw_lock) 45# define do_raw_read_unlock(rwlock) do {arch_read_unlock(&(rwlock)->raw_lock); __release(lock); } while (0) 46# define do_raw_write_lock(rwlock) do {__acquire(lock); arch_write_lock(&(rwlock)->raw_lock); } while (0) 47# define do_raw_write_lock_flags(lock, flags) \ 48 do {__acquire(lock); arch_write_lock_flags(&(lock)->raw_lock, *(flags)); } while (0) 49# define do_raw_write_trylock(rwlock) arch_write_trylock(&(rwlock)->raw_lock) 50# define do_raw_write_unlock(rwlock) do {arch_write_unlock(&(rwlock)->raw_lock); __release(lock); } while (0) 51#endif 52 53#define read_can_lock(rwlock) arch_read_can_lock(&(rwlock)->raw_lock) 54#define write_can_lock(rwlock) arch_write_can_lock(&(rwlock)->raw_lock) 55 56/* 57 * Define the various rw_lock methods. Note we define these 58 * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various 59 * methods are defined as nops in the case they are not required. 60 */ 61#define read_trylock(lock) __cond_lock(lock, _raw_read_trylock(lock)) 62#define write_trylock(lock) __cond_lock(lock, _raw_write_trylock(lock)) 63 64#define write_lock(lock) _raw_write_lock(lock) 65#define read_lock(lock) _raw_read_lock(lock) 66 67#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) 68 69#define read_lock_irqsave(lock, flags) \ 70 do { \ 71 typecheck(unsigned long, flags); \ 72 flags = _raw_read_lock_irqsave(lock); \ 73 } while (0) 74#define write_lock_irqsave(lock, flags) \ 75 do { \ 76 typecheck(unsigned long, flags); \ 77 flags = _raw_write_lock_irqsave(lock); \ 78 } while (0) 79 80#else 81 82#define read_lock_irqsave(lock, flags) \ 83 do { \ 84 typecheck(unsigned long, flags); \ 85 _raw_read_lock_irqsave(lock, flags); \ 86 } while (0) 87#define write_lock_irqsave(lock, flags) \ 88 do { \ 89 typecheck(unsigned long, flags); \ 90 _raw_write_lock_irqsave(lock, flags); \ 91 } while (0) 92 93#endif 94 95#define read_lock_irq(lock) _raw_read_lock_irq(lock) 96#define read_lock_bh(lock) _raw_read_lock_bh(lock) 97#define write_lock_irq(lock) _raw_write_lock_irq(lock) 98#define write_lock_bh(lock) _raw_write_lock_bh(lock) 99#define read_unlock(lock) _raw_read_unlock(lock) 100#define write_unlock(lock) _raw_write_unlock(lock) 101#define read_unlock_irq(lock) _raw_read_unlock_irq(lock) 102#define write_unlock_irq(lock) _raw_write_unlock_irq(lock) 103 104#define read_unlock_irqrestore(lock, flags) \ 105 do { \ 106 typecheck(unsigned long, flags); \ 107 _raw_read_unlock_irqrestore(lock, flags); \ 108 } while (0) 109#define read_unlock_bh(lock) _raw_read_unlock_bh(lock) 110 111#define write_unlock_irqrestore(lock, flags) \ 112 do { \ 113 typecheck(unsigned long, flags); \ 114 _raw_write_unlock_irqrestore(lock, flags); \ 115 } while (0) 116#define write_unlock_bh(lock) _raw_write_unlock_bh(lock) 117 118#define write_trylock_irqsave(lock, flags) \ 119({ \ 120 local_irq_save(flags); \ 121 write_trylock(lock) ? \ 122 1 : ({ local_irq_restore(flags); 0; }); \ 123}) 124 125#endif /* __LINUX_RWLOCK_H */ 126