X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-powerpc%2Fatomic.h;h=f038e33e6d48677d0da1d5150dfc0b5f1f8a6931;hb=refs%2Fheads%2Fvserver;hp=53283e2540b381ff086508d69052dd1b188bc6d1;hpb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;p=linux-2.6.git

diff --git a/include/asm-powerpc/atomic.h b/include/asm-powerpc/atomic.h
index 53283e254..f038e33e6 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");