diff options
Diffstat (limited to 'include/asm-i386/cmpxchg.h')
| -rw-r--r-- | include/asm-i386/cmpxchg.h | 16 |
1 files changed, 6 insertions, 10 deletions
diff --git a/include/asm-i386/cmpxchg.h b/include/asm-i386/cmpxchg.h index 7adcef0cd53b..f86ede28f6dc 100644 --- a/include/asm-i386/cmpxchg.h +++ b/include/asm-i386/cmpxchg.h @@ -3,14 +3,16 @@ #include <linux/bitops.h> /* for LOCK_PREFIX */ +/* + * Note: if you use set64_bit(), __cmpxchg64(), or their variants, you + * you need to test for the feature in boot_cpu_data. + */ + #define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr)))) struct __xchg_dummy { unsigned long a[100]; }; #define __xg(x) ((struct __xchg_dummy *)(x)) - -#ifdef CONFIG_X86_CMPXCHG64 - /* * The semantics of XCHGCMP8B are a bit strange, this is why * there is a loop and the loading of %%eax and %%edx has to @@ -32,7 +34,7 @@ static inline void __set_64bit (unsigned long long * ptr, "\n1:\t" "movl (%0), %%eax\n\t" "movl 4(%0), %%edx\n\t" - "lock cmpxchg8b (%0)\n\t" + LOCK_PREFIX "cmpxchg8b (%0)\n\t" "jnz 1b" : /* no outputs */ : "D"(ptr), @@ -65,8 +67,6 @@ static inline void __set_64bit_var (unsigned long long *ptr, __set_64bit(ptr, (unsigned int)(value), (unsigned int)((value)>>32ULL) ) : \ __set_64bit(ptr, ll_low(value), ll_high(value)) ) -#endif - /* * Note: no "lock" prefix even on SMP: xchg always implies lock anyway * Note 2: xchg has side effect, so that attribute volatile is necessary, @@ -252,8 +252,6 @@ static inline unsigned long cmpxchg_386(volatile void *ptr, unsigned long old, }) #endif -#ifdef CONFIG_X86_CMPXCHG64 - static inline unsigned long long __cmpxchg64(volatile void *ptr, unsigned long long old, unsigned long long new) { @@ -289,5 +287,3 @@ static inline unsigned long long __cmpxchg64_local(volatile void *ptr, ((__typeof__(*(ptr)))__cmpxchg64_local((ptr),(unsigned long long)(o),\ (unsigned long long)(n))) #endif - -#endif |