#ifndef __LINUX_RWLOCK_H #define __LINUX_RWLOCK_H #ifndef __LINUX_INSIDE_SPINLOCK_H # error "Please do not 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) #ifdef CONFIG_DEBUG_LOCK_ALLOC #define write_lock_nested(lock, subclass) _raw_write_lock_nested(lock, subclass) #else #define write_lock_nested(lock, subclass) _raw_write_lock(lock) #endif #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 */