| #ifndef __LINUX_RWLOCK_H |
| #define __LINUX_RWLOCK_H |
| |
| #ifndef __LINUX_SPINLOCK_H |
| # error "please don't include this file directly" |
| #endif |
| |
| /* |
| * rwlock related methods |
| * |
| * split out from spinlock.h |
| * |
| * portions Copyright 2005, Red Hat, Inc., Ingo Molnar |
| * Released under the General Public License (GPL). |
| */ |
| |
| #ifdef CONFIG_DEBUG_SPINLOCK |
| extern void __rwlock_init(rwlock_t *lock, const char *name, |
| struct lock_class_key *key); |
| # define rwlock_init(lock) \ |
| do { \ |
| static struct lock_class_key __key; \ |
| \ |
| __rwlock_init((lock), #lock, &__key); \ |
| } while (0) |
| #else |
| # define rwlock_init(lock) \ |
| do { *(lock) = __RW_LOCK_UNLOCKED(lock); } while (0) |
| #endif |
| |
| #ifdef CONFIG_DEBUG_SPINLOCK |
| extern void do_raw_read_lock(rwlock_t *lock) __acquires(lock); |
| extern int do_raw_read_trylock(rwlock_t *lock); |
| extern void do_raw_read_unlock(rwlock_t *lock) __releases(lock); |
| extern void do_raw_write_lock(rwlock_t *lock) __acquires(lock); |
| extern int do_raw_write_trylock(rwlock_t *lock); |
| extern void do_raw_write_unlock(rwlock_t *lock) __releases(lock); |
| #else |
| # define do_raw_read_lock(rwlock) do {__acquire(lock); arch_read_lock(&(rwlock)->raw_lock); } while (0) |
| # define do_raw_read_trylock(rwlock) arch_read_trylock(&(rwlock)->raw_lock) |
| # define do_raw_read_unlock(rwlock) do {arch_read_unlock(&(rwlock)->raw_lock); __release(lock); } while (0) |
| # define do_raw_write_lock(rwlock) do {__acquire(lock); arch_write_lock(&(rwlock)->raw_lock); } while (0) |
| # define do_raw_write_trylock(rwlock) arch_write_trylock(&(rwlock)->raw_lock) |
| # define do_raw_write_unlock(rwlock) do {arch_write_unlock(&(rwlock)->raw_lock); __release(lock); } while (0) |
| #endif |
| |
| /* |
| * Define the various rw_lock methods. Note we define these |
| * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various |
| * methods are defined as nops in the case they are not required. |
| */ |
| #define read_trylock(lock) __cond_lock(lock, _raw_read_trylock(lock)) |
| #define write_trylock(lock) __cond_lock(lock, _raw_write_trylock(lock)) |
| |
| #define write_lock(lock) _raw_write_lock(lock) |
| #define read_lock(lock) _raw_read_lock(lock) |
| |
| #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) |
| |
| #define read_lock_irqsave(lock, flags) \ |
| do { \ |
| typecheck(unsigned long, flags); \ |
| flags = _raw_read_lock_irqsave(lock); \ |
| } while (0) |
| #define write_lock_irqsave(lock, flags) \ |
| do { \ |
| typecheck(unsigned long, flags); \ |
| flags = _raw_write_lock_irqsave(lock); \ |
| } while (0) |
| |
| #else |
| |
| #define read_lock_irqsave(lock, flags) \ |
| do { \ |
| typecheck(unsigned long, flags); \ |
| _raw_read_lock_irqsave(lock, flags); \ |
| } while (0) |
| #define write_lock_irqsave(lock, flags) \ |
| do { \ |
| typecheck(unsigned long, flags); \ |
| _raw_write_lock_irqsave(lock, flags); \ |
| } while (0) |
| |
| #endif |
| |
| #define read_lock_irq(lock) _raw_read_lock_irq(lock) |
| #define read_lock_bh(lock) _raw_read_lock_bh(lock) |
| #define write_lock_irq(lock) _raw_write_lock_irq(lock) |
| #define write_lock_bh(lock) _raw_write_lock_bh(lock) |
| #define read_unlock(lock) _raw_read_unlock(lock) |
| #define write_unlock(lock) _raw_write_unlock(lock) |
| #define read_unlock_irq(lock) _raw_read_unlock_irq(lock) |
| #define write_unlock_irq(lock) _raw_write_unlock_irq(lock) |
| |
| #define read_unlock_irqrestore(lock, flags) \ |
| do { \ |
| typecheck(unsigned long, flags); \ |
| _raw_read_unlock_irqrestore(lock, flags); \ |
| } while (0) |
| #define read_unlock_bh(lock) _raw_read_unlock_bh(lock) |
| |
| #define write_unlock_irqrestore(lock, flags) \ |
| do { \ |
| typecheck(unsigned long, flags); \ |
| _raw_write_unlock_irqrestore(lock, flags); \ |
| } while (0) |
| #define write_unlock_bh(lock) _raw_write_unlock_bh(lock) |
| |
| #define write_trylock_irqsave(lock, flags) \ |
| ({ \ |
| local_irq_save(flags); \ |
| write_trylock(lock) ? \ |
| 1 : ({ local_irq_restore(flags); 0; }); \ |
| }) |
| |
| #ifdef arch_rwlock_is_contended |
| #define rwlock_is_contended(lock) \ |
| arch_rwlock_is_contended(&(lock)->raw_lock) |
| #else |
| #define rwlock_is_contended(lock) ((void)(lock), 0) |
| #endif /* arch_rwlock_is_contended */ |
| |
| #endif /* __LINUX_RWLOCK_H */ |