diff options
| -rw-r--r-- | include/asm-powerpc/atomic.h | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/include/asm-powerpc/atomic.h b/include/asm-powerpc/atomic.h index 53283e2540b..f038e33e6d4 100644 --- a/include/asm-powerpc/atomic.h +++ b/include/asm-powerpc/atomic.h @@ -207,7 +207,8 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u) /* * Atomically test *v and decrement if it is greater than 0. - * The function returns the old value of *v minus 1. + * The function returns the old value of *v minus 1, even if + * the atomic variable, v, was not decremented. */ static __inline__ int atomic_dec_if_positive(atomic_t *v) { @@ -216,14 +217,15 @@ static __inline__ int atomic_dec_if_positive(atomic_t *v) __asm__ __volatile__( LWSYNC_ON_SMP "1: lwarx %0,0,%1 # atomic_dec_if_positive\n\ - addic. %0,%0,-1\n\ + cmpwi %0,1\n\ + addi %0,%0,-1\n\ blt- 2f\n" PPC405_ERR77(0,%1) " stwcx. %0,0,%1\n\ bne- 1b" ISYNC_ON_SMP "\n\ -2:" : "=&r" (t) +2:" : "=&b" (t) : "r" (&v->counter) : "cc", "memory"); |