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) \ 21 do { \ 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 42 #ifndef arch_read_lock_flags 43 # define arch_read_lock_flags(lock, flags) arch_read_lock(lock) 44 #endif 45 46 #ifndef arch_write_lock_flags 47 # define arch_write_lock_flags(lock, flags) arch_write_lock(lock) 48 #endif 49 50 # define do_raw_read_lock(rwlock) do {__acquire(lock); arch_read_lock(&(rwlock)->raw_lock); } while (0) 51 # define do_raw_read_lock_flags(lock, flags) \ 52 do {__acquire(lock); arch_read_lock_flags(&(lock)->raw_lock, *(flags)); } while (0) 53 # define do_raw_read_trylock(rwlock) arch_read_trylock(&(rwlock)->raw_lock) 54 # define do_raw_read_unlock(rwlock) do {arch_read_unlock(&(rwlock)->raw_lock); __release(lock); } while (0) 55 # define do_raw_write_lock(rwlock) do {__acquire(lock); arch_write_lock(&(rwlock)->raw_lock); } while (0) 56 # define do_raw_write_lock_flags(lock, flags) \ 57 do {__acquire(lock); arch_write_lock_flags(&(lock)->raw_lock, *(flags)); } while (0) 58 # define do_raw_write_trylock(rwlock) arch_write_trylock(&(rwlock)->raw_lock) 59 # define do_raw_write_unlock(rwlock) do {arch_write_unlock(&(rwlock)->raw_lock); __release(lock); } while (0) 60 #endif 61 62 /* 63 * Define the various rw_lock methods. Note we define these 64 * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various 65 * methods are defined as nops in the case they are not required. 66 */ 67 #define read_trylock(lock) __cond_lock(lock, _raw_read_trylock(lock)) 68 #define write_trylock(lock) __cond_lock(lock, _raw_write_trylock(lock)) 69 70 #define write_lock(lock) _raw_write_lock(lock) 71 #define read_lock(lock) _raw_read_lock(lock) 72 73 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) 74 75 #define read_lock_irqsave(lock, flags) \ 76 do { \ 77 typecheck(unsigned long, flags); \ 78 flags = _raw_read_lock_irqsave(lock); \ 79 } while (0) 80 #define write_lock_irqsave(lock, flags) \ 81 do { \ 82 typecheck(unsigned long, flags); \ 83 flags = _raw_write_lock_irqsave(lock); \ 84 } while (0) 85 86 #else 87 88 #define read_lock_irqsave(lock, flags) \ 89 do { \ 90 typecheck(unsigned long, flags); \ 91 _raw_read_lock_irqsave(lock, flags); \ 92 } while (0) 93 #define write_lock_irqsave(lock, flags) \ 94 do { \ 95 typecheck(unsigned long, flags); \ 96 _raw_write_lock_irqsave(lock, flags); \ 97 } while (0) 98 99 #endif 100 101 #define read_lock_irq(lock) _raw_read_lock_irq(lock) 102 #define read_lock_bh(lock) _raw_read_lock_bh(lock) 103 #define write_lock_irq(lock) _raw_write_lock_irq(lock) 104 #define write_lock_bh(lock) _raw_write_lock_bh(lock) 105 #define read_unlock(lock) _raw_read_unlock(lock) 106 #define write_unlock(lock) _raw_write_unlock(lock) 107 #define read_unlock_irq(lock) _raw_read_unlock_irq(lock) 108 #define write_unlock_irq(lock) _raw_write_unlock_irq(lock) 109 110 #define read_unlock_irqrestore(lock, flags) \ 111 do { \ 112 typecheck(unsigned long, flags); \ 113 _raw_read_unlock_irqrestore(lock, flags); \ 114 } while (0) 115 #define read_unlock_bh(lock) _raw_read_unlock_bh(lock) 116 117 #define write_unlock_irqrestore(lock, flags) \ 118 do { \ 119 typecheck(unsigned long, flags); \ 120 _raw_write_unlock_irqrestore(lock, flags); \ 121 } while (0) 122 #define write_unlock_bh(lock) _raw_write_unlock_bh(lock) 123 124 #define write_trylock_irqsave(lock, flags) \ 125 ({ \ 126 local_irq_save(flags); \ 127 write_trylock(lock) ? \ 128 1 : ({ local_irq_restore(flags); 0; }); \ 129 }) 130 131 #endif /* __LINUX_RWLOCK_H */ 132