x86-32: Allow UP/SMP lock replacement in cmpxchg64

Use the functionality just introduced in the previous patch: mark the
lock prefixes in cmpxchg64 alternatives for UP removal.

Changes in v2:
- Naming change

Signed-off-by: Luca Barbieri <luca@luca-barbieri.com>
LKML-Reference: <1267005265-27958-3-git-send-email-luca@luca-barbieri.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/arch/x86/include/asm/cmpxchg_32.h b/arch/x86/include/asm/cmpxchg_32.h
index ffb9bb6b6c37..8859e12dd3cf 100644
--- a/arch/x86/include/asm/cmpxchg_32.h
+++ b/arch/x86/include/asm/cmpxchg_32.h
@@ -271,7 +271,8 @@ extern unsigned long long cmpxchg_486_u64(volatile void *, u64, u64);
         __typeof__(*(ptr)) __ret;                               \
         __typeof__(*(ptr)) __old = (o);                         \
         __typeof__(*(ptr)) __new = (n);                         \
-        alternative_io("call cmpxchg8b_emu",                    \
+        alternative_io(LOCK_PREFIX_HERE                         \
+                        "call cmpxchg8b_emu",                   \
                         "lock; cmpxchg8b (%%esi)" ,             \
                        X86_FEATURE_CX8,                         \
                        "=A" (__ret),                            \