diff options
| author | David S. Miller <davem@sunset.davemloft.net> | 2006-01-23 21:03:56 -0800 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-01-23 21:03:56 -0800 |
| commit | d3ed309a718bc6f79dc485a6d18731990daeee5e (patch) | |
| tree | de908eec9cff81303038b0523169027748f38fa0 /include | |
| parent | 4415863773eb0eeceba7318238ec0f63b0b5847a (diff) | |
[SPARC64]: Implement __raw_read_trylock()
generic__raw_read_trylock() just does a raw_read_lock() so that
isn't very useful.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-sparc64/spinlock.h | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/include/asm-sparc64/spinlock.h b/include/asm-sparc64/spinlock.h index ec85d12d73b..508c416e9d6 100644 --- a/include/asm-sparc64/spinlock.h +++ b/include/asm-sparc64/spinlock.h @@ -131,6 +131,28 @@ static void inline __read_lock(raw_rwlock_t *lock) : "memory"); } +static int inline __read_trylock(raw_rwlock_t *lock) +{ + int tmp1, tmp2; + + __asm__ __volatile__ ( +"1: ldsw [%2], %0\n" +" brlz,a,pn %0, 2f\n" +" mov 0, %0\n" +" add %0, 1, %1\n" +" cas [%2], %0, %1\n" +" cmp %0, %1\n" +" membar #StoreLoad | #StoreStore\n" +" bne,pn %%icc, 1b\n" +" mov 1, %0\n" +"2:" + : "=&r" (tmp1), "=&r" (tmp2) + : "r" (lock) + : "memory"); + + return tmp1; +} + static void inline __read_unlock(raw_rwlock_t *lock) { unsigned long tmp1, tmp2; @@ -211,12 +233,12 @@ static int inline __write_trylock(raw_rwlock_t *lock) } #define __raw_read_lock(p) __read_lock(p) +#define __raw_read_trylock(p) __read_trylock(p) #define __raw_read_unlock(p) __read_unlock(p) #define __raw_write_lock(p) __write_lock(p) #define __raw_write_unlock(p) __write_unlock(p) #define __raw_write_trylock(p) __write_trylock(p) -#define __raw_read_trylock(lock) generic__raw_read_trylock(lock) #define __raw_read_can_lock(rw) (!((rw)->lock & 0x80000000UL)) #define __raw_write_can_lock(rw) (!(rw)->lock) |