diff options
Diffstat (limited to 'include/asm-arm/spinlock.h')
| -rw-r--r-- | include/asm-arm/spinlock.h | 35 |
1 files changed, 19 insertions, 16 deletions
diff --git a/include/asm-arm/spinlock.h b/include/asm-arm/spinlock.h index 182323619ca..9705d5eec94 100644 --- a/include/asm-arm/spinlock.h +++ b/include/asm-arm/spinlock.h @@ -79,7 +79,8 @@ typedef struct { } rwlock_t; #define RW_LOCK_UNLOCKED (rwlock_t) { 0 } -#define rwlock_init(x) do { *(x) + RW_LOCK_UNLOCKED; } while (0) +#define rwlock_init(x) do { *(x) = RW_LOCK_UNLOCKED; } while (0) +#define rwlock_is_locked(x) (*((volatile unsigned int *)(x)) != 0) /* * Write locks are easy - we just set bit 31. When unlocking, we can @@ -100,6 +101,21 @@ static inline void _raw_write_lock(rwlock_t *rw) : "cc", "memory"); } +static inline int _raw_write_trylock(rwlock_t *rw) +{ + unsigned long tmp; + + __asm__ __volatile__( +"1: ldrex %0, [%1]\n" +" teq %0, #0\n" +" strexeq %0, %2, [%1]" + : "=&r" (tmp) + : "r" (&rw->lock), "r" (0x80000000) + : "cc", "memory"); + + return tmp == 0; +} + static inline void _raw_write_unlock(rwlock_t *rw) { __asm__ __volatile__( @@ -138,6 +154,8 @@ static inline void _raw_read_lock(rwlock_t *rw) static inline void _raw_read_unlock(rwlock_t *rw) { + unsigned long tmp, tmp2; + __asm__ __volatile__( "1: ldrex %0, [%2]\n" " sub %0, %0, #1\n" @@ -151,19 +169,4 @@ static inline void _raw_read_unlock(rwlock_t *rw) #define _raw_read_trylock(lock) generic_raw_read_trylock(lock) -static inline int _raw_write_trylock(rwlock_t *rw) -{ - unsigned long tmp; - - __asm__ __volatile__( -"1: ldrex %0, [%1]\n" -" teq %0, #0\n" -" strexeq %0, %2, [%1]" - : "=&r" (tmp) - : "r" (&rw->lock), "r" (0x80000000) - : "cc", "memory"); - - return tmp == 0; -} - #endif /* __ASM_SPINLOCK_H */ |