diff options
Diffstat (limited to 'include/asm-ia64/spinlock.h')
| -rw-r--r-- | include/asm-ia64/spinlock.h | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/include/asm-ia64/spinlock.h b/include/asm-ia64/spinlock.h index 5b78611411c3..0c91a76c5ea3 100644 --- a/include/asm-ia64/spinlock.h +++ b/include/asm-ia64/spinlock.h @@ -201,6 +201,16 @@ static inline void __raw_write_unlock(raw_rwlock_t *x) #endif /* !ASM_SUPPORTED */ -#define __raw_read_trylock(lock) generic__raw_read_trylock(lock) +static inline int __raw_read_trylock(raw_rwlock_t *x) +{ + union { + raw_rwlock_t lock; + __u32 word; + } old, new; + old.lock = new.lock = *x; + old.lock.write_lock = new.lock.write_lock = 0; + ++new.lock.read_counter; + return (u32)ia64_cmpxchg4_acq((__u32 *)(x), new.word, old.word) == old.word; +} #endif /* _ASM_IA64_SPINLOCK_H */ |