fix missing barrier instructions in powerpc atomic asm

diff --git a/arch/powerpc/atomic.h b/arch/powerpc/atomic.h
index a1049bdb391af733b591417af39173283dc9a60f..c4ad40cd5d5e098b6242aaa362911f5414e8af32 100644 (file)
--- a/arch/powerpc/atomic.h
+++ b/arch/powerpc/atomic.h
@@ -25,11 +25,14 @@ static inline int a_ctz_64(uint64_t x)
 
 static inline int a_cas(volatile int *p, int t, int s)
 {
-       __asm__("1:     lwarx %0, 0, %4\n"
+       __asm__("\n"
+               "       sync\n"
+               "1:     lwarx %0, 0, %4\n"
                "       cmpw %0, %2\n"
                "       bne 1f\n"
                "       stwcx. %3, 0, %4\n"
                "       bne- 1b\n"
+               "       isync\n"
                "1:     \n"
                : "=&r"(t), "+m"(*p) : "r"(t), "r"(s), "r"(p) : "cc", "memory" );
         return t;