diff options
Diffstat (limited to 'arch/x86/include/asm/cmpxchg_32.h')
| -rw-r--r-- | arch/x86/include/asm/cmpxchg_32.h | 171 |
1 files changed, 2 insertions, 169 deletions
diff --git a/arch/x86/include/asm/cmpxchg_32.h b/arch/x86/include/asm/cmpxchg_32.h index 284a6e8f7ce..f8bf2eecab8 100644 --- a/arch/x86/include/asm/cmpxchg_32.h +++ b/arch/x86/include/asm/cmpxchg_32.h @@ -1,61 +1,11 @@ #ifndef _ASM_X86_CMPXCHG_32_H #define _ASM_X86_CMPXCHG_32_H -#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. */ -extern void __xchg_wrong_size(void); - -/* - * Note: no "lock" prefix even on SMP: xchg always implies lock anyway. - * Since this is generally used to protect other memory information, we - * use "asm volatile" and "memory" clobbers to prevent gcc from moving - * information around. - */ -#define __xchg(x, ptr, size) \ -({ \ - __typeof(*(ptr)) __x = (x); \ - switch (size) { \ - case 1: \ - { \ - volatile u8 *__ptr = (volatile u8 *)(ptr); \ - asm volatile("xchgb %0,%1" \ - : "=q" (__x), "+m" (*__ptr) \ - : "0" (__x) \ - : "memory"); \ - break; \ - } \ - case 2: \ - { \ - volatile u16 *__ptr = (volatile u16 *)(ptr); \ - asm volatile("xchgw %0,%1" \ - : "=r" (__x), "+m" (*__ptr) \ - : "0" (__x) \ - : "memory"); \ - break; \ - } \ - case 4: \ - { \ - volatile u32 *__ptr = (volatile u32 *)(ptr); \ - asm volatile("xchgl %0,%1" \ - : "=r" (__x), "+m" (*__ptr) \ - : "0" (__x) \ - : "memory"); \ - break; \ - } \ - default: \ - __xchg_wrong_size(); \ - } \ - __x; \ -}) - -#define xchg(ptr, v) \ - __xchg((v), (ptr), sizeof(*ptr)) - /* * CMPXCHG8B only writes to the target if we had the previous * value in registers, otherwise it acts as a read and gives us the @@ -84,74 +34,8 @@ static inline void set_64bit(volatile u64 *ptr, u64 value) : "memory"); } -extern void __cmpxchg_wrong_size(void); - -/* - * Atomic compare and exchange. Compare OLD with MEM, if identical, - * store NEW in MEM. Return the initial value in MEM. Success is - * indicated by comparing RETURN with OLD. - */ -#define __raw_cmpxchg(ptr, old, new, size, lock) \ -({ \ - __typeof__(*(ptr)) __ret; \ - __typeof__(*(ptr)) __old = (old); \ - __typeof__(*(ptr)) __new = (new); \ - switch (size) { \ - case 1: \ - { \ - volatile u8 *__ptr = (volatile u8 *)(ptr); \ - asm volatile(lock "cmpxchgb %2,%1" \ - : "=a" (__ret), "+m" (*__ptr) \ - : "q" (__new), "0" (__old) \ - : "memory"); \ - break; \ - } \ - case 2: \ - { \ - volatile u16 *__ptr = (volatile u16 *)(ptr); \ - asm volatile(lock "cmpxchgw %2,%1" \ - : "=a" (__ret), "+m" (*__ptr) \ - : "r" (__new), "0" (__old) \ - : "memory"); \ - break; \ - } \ - case 4: \ - { \ - volatile u32 *__ptr = (volatile u32 *)(ptr); \ - asm volatile(lock "cmpxchgl %2,%1" \ - : "=a" (__ret), "+m" (*__ptr) \ - : "r" (__new), "0" (__old) \ - : "memory"); \ - break; \ - } \ - default: \ - __cmpxchg_wrong_size(); \ - } \ - __ret; \ -}) - -#define __cmpxchg(ptr, old, new, size) \ - __raw_cmpxchg((ptr), (old), (new), (size), LOCK_PREFIX) - -#define __sync_cmpxchg(ptr, old, new, size) \ - __raw_cmpxchg((ptr), (old), (new), (size), "lock; ") - -#define __cmpxchg_local(ptr, old, new, size) \ - __raw_cmpxchg((ptr), (old), (new), (size), "") - -#ifdef CONFIG_X86_CMPXCHG #define __HAVE_ARCH_CMPXCHG 1 -#define cmpxchg(ptr, old, new) \ - __cmpxchg((ptr), (old), (new), sizeof(*ptr)) - -#define sync_cmpxchg(ptr, old, new) \ - __sync_cmpxchg((ptr), (old), (new), sizeof(*ptr)) - -#define cmpxchg_local(ptr, old, new) \ - __cmpxchg_local((ptr), (old), (new), sizeof(*ptr)) -#endif - #ifdef CONFIG_X86_CMPXCHG64 #define cmpxchg64(ptr, o, n) \ ((__typeof__(*(ptr)))__cmpxchg64((ptr), (unsigned long long)(o), \ @@ -187,59 +71,6 @@ static inline u64 __cmpxchg64_local(volatile u64 *ptr, u64 old, u64 new) return prev; } -#ifndef CONFIG_X86_CMPXCHG -/* - * Building a kernel capable running on 80386. It may be necessary to - * simulate the cmpxchg on the 80386 CPU. For that purpose we define - * a function for each of the sizes we support. - */ - -extern unsigned long cmpxchg_386_u8(volatile void *, u8, u8); -extern unsigned long cmpxchg_386_u16(volatile void *, u16, u16); -extern unsigned long cmpxchg_386_u32(volatile void *, u32, u32); - -static inline unsigned long cmpxchg_386(volatile void *ptr, unsigned long old, - unsigned long new, int size) -{ - switch (size) { - case 1: - return cmpxchg_386_u8(ptr, old, new); - case 2: - return cmpxchg_386_u16(ptr, old, new); - case 4: - return cmpxchg_386_u32(ptr, old, new); - } - return old; -} - -#define cmpxchg(ptr, o, n) \ -({ \ - __typeof__(*(ptr)) __ret; \ - if (likely(boot_cpu_data.x86 > 3)) \ - __ret = (__typeof__(*(ptr)))__cmpxchg((ptr), \ - (unsigned long)(o), (unsigned long)(n), \ - sizeof(*(ptr))); \ - else \ - __ret = (__typeof__(*(ptr)))cmpxchg_386((ptr), \ - (unsigned long)(o), (unsigned long)(n), \ - sizeof(*(ptr))); \ - __ret; \ -}) -#define cmpxchg_local(ptr, o, n) \ -({ \ - __typeof__(*(ptr)) __ret; \ - if (likely(boot_cpu_data.x86 > 3)) \ - __ret = (__typeof__(*(ptr)))__cmpxchg_local((ptr), \ - (unsigned long)(o), (unsigned long)(n), \ - sizeof(*(ptr))); \ - else \ - __ret = (__typeof__(*(ptr)))cmpxchg_386((ptr), \ - (unsigned long)(o), (unsigned long)(n), \ - sizeof(*(ptr))); \ - __ret; \ -}) -#endif - #ifndef CONFIG_X86_CMPXCHG64 /* * Building a kernel capable running on 80386 and 80486. It may be necessary @@ -280,4 +111,6 @@ static inline unsigned long cmpxchg_386(volatile void *ptr, unsigned long old, #endif +#define system_has_cmpxchg_double() cpu_has_cx8 + #endif /* _ASM_X86_CMPXCHG_32_H */ |