diff options
Diffstat (limited to 'include/linux/spinlock.h')
| -rw-r--r-- | include/linux/spinlock.h | 28 |
1 files changed, 20 insertions, 8 deletions
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h index 47dd0cebd204..d9510e8522d4 100644 --- a/include/linux/spinlock.h +++ b/include/linux/spinlock.h @@ -180,8 +180,6 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock) #ifdef CONFIG_DEBUG_LOCK_ALLOC # define raw_spin_lock_nested(lock, subclass) \ _raw_spin_lock_nested(lock, subclass) -# define raw_spin_lock_bh_nested(lock, subclass) \ - _raw_spin_lock_bh_nested(lock, subclass) # define raw_spin_lock_nest_lock(lock, nest_lock) \ do { \ @@ -197,7 +195,6 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock) # define raw_spin_lock_nested(lock, subclass) \ _raw_spin_lock(((void)(subclass), (lock))) # define raw_spin_lock_nest_lock(lock, nest_lock) _raw_spin_lock(lock) -# define raw_spin_lock_bh_nested(lock, subclass) _raw_spin_lock_bh(lock) #endif #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) @@ -317,11 +314,6 @@ do { \ raw_spin_lock_nested(spinlock_check(lock), subclass); \ } while (0) -#define spin_lock_bh_nested(lock, subclass) \ -do { \ - raw_spin_lock_bh_nested(spinlock_check(lock), subclass);\ -} while (0) - #define spin_lock_nest_lock(lock, nest_lock) \ do { \ raw_spin_lock_nest_lock(spinlock_check(lock), nest_lock); \ @@ -377,6 +369,26 @@ static __always_inline int spin_trylock_irq(spinlock_t *lock) raw_spin_trylock_irqsave(spinlock_check(lock), flags); \ }) +/** + * spin_unlock_wait - Interpose between successive critical sections + * @lock: the spinlock whose critical sections are to be interposed. + * + * Semantically this is equivalent to a spin_lock() immediately + * followed by a spin_unlock(). However, most architectures have + * more efficient implementations in which the spin_unlock_wait() + * cannot block concurrent lock acquisition, and in some cases + * where spin_unlock_wait() does not write to the lock variable. + * Nevertheless, spin_unlock_wait() can have high overhead, so if + * you feel the need to use it, please check to see if there is + * a better way to get your job done. + * + * The ordering guarantees provided by spin_unlock_wait() are: + * + * 1. All accesses preceding the spin_unlock_wait() happen before + * any accesses in later critical sections for this same lock. + * 2. All accesses following the spin_unlock_wait() happen after + * any accesses in earlier critical sections for this same lock. + */ static __always_inline void spin_unlock_wait(spinlock_t *lock) { raw_spin_unlock_wait(&lock->rlock); |