diff options
| author | Zoltan Menyhart <Zoltan.Menyhart@bull.net> | 2006-01-13 17:25:23 +0100 |
|---|---|---|
| committer | Tony Luck <tony.luck@intel.com> | 2006-01-17 23:04:00 +0100 |
| commit | 4b16bfbf8f8013fefb49592d030ff87651ab48cb (patch) | |
| tree | ce9150f8ceac6150261f5bc69afdf9d2e95def19 /include/asm-ia64/semaphore.h | |
| parent | [IA64] Zonelists for nodes without cpus (diff) | |
| download | linux-4b16bfbf8f8013fefb49592d030ff87651ab48cb.tar.xz linux-4b16bfbf8f8013fefb49592d030ff87651ab48cb.zip | |
[IA64] Fix bug in ia64 specific down() function
Chen, Kenneth W wrote:
> The memory order semantics for include/asm-ia64/semaphore.h:down()
> doesn't look right. It is using atomic_dec_return, which eventually
> translate into ia64_fetch_and_add() that uses release semantics.
> Shouldn't it use acquire semantics?
Use ia64_fetchadd() instead of atomic_dec_return()
Acked-by: Ken Chen <kenneth.w.chen@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'include/asm-ia64/semaphore.h')
| -rw-r--r-- | include/asm-ia64/semaphore.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/include/asm-ia64/semaphore.h b/include/asm-ia64/semaphore.h index bb8906285fab..f483eeb95dd1 100644 --- a/include/asm-ia64/semaphore.h +++ b/include/asm-ia64/semaphore.h @@ -61,7 +61,7 @@ static inline void down (struct semaphore *sem) { might_sleep(); - if (atomic_dec_return(&sem->count) < 0) + if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) __down(sem); } @@ -75,7 +75,7 @@ down_interruptible (struct semaphore * sem) int ret = 0; might_sleep(); - if (atomic_dec_return(&sem->count) < 0) + if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) ret = __down_interruptible(sem); return ret; } @@ -85,7 +85,7 @@ down_trylock (struct semaphore *sem) { int ret = 0; - if (atomic_dec_return(&sem->count) < 0) + if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) ret = __down_trylock(sem); return ret; } @@ -93,7 +93,7 @@ down_trylock (struct semaphore *sem) static inline void up (struct semaphore * sem) { - if (atomic_inc_return(&sem->count) <= 0) + if (ia64_fetchadd(1, &sem->count.counter, rel) <= -1) __up(sem); } |