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Diffstat (limited to 'arch/x86/include/asm/cmpxchg_64.h')
-rw-r--r--arch/x86/include/asm/cmpxchg_64.h174
1 files changed, 44 insertions, 130 deletions
diff --git a/arch/x86/include/asm/cmpxchg_64.h b/arch/x86/include/asm/cmpxchg_64.h
index 423ae58aa020..285da02c38fa 100644
--- a/arch/x86/include/asm/cmpxchg_64.h
+++ b/arch/x86/include/asm/cmpxchg_64.h
@@ -1,154 +1,68 @@
#ifndef _ASM_X86_CMPXCHG_64_H
#define _ASM_X86_CMPXCHG_64_H
-#include <asm/alternative.h> /* Provides LOCK_PREFIX */
-
static inline void set_64bit(volatile u64 *ptr, u64 val)
{
*ptr = val;
}
-extern void __xchg_wrong_size(void);
-extern void __cmpxchg_wrong_size(void);
+#define __HAVE_ARCH_CMPXCHG 1
-/*
- * 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) \
+#define cmpxchg64(ptr, o, n) \
({ \
- __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; \
- } \
- case 8: \
- { \
- volatile u64 *__ptr = (volatile u64 *)(ptr); \
- asm volatile("xchgq %0,%1" \
- : "=r" (__x), "+m" (*__ptr) \
- : "0" (__x) \
- : "memory"); \
- break; \
- } \
- default: \
- __xchg_wrong_size(); \
- } \
- __x; \
+ BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
+ cmpxchg((ptr), (o), (n)); \
})
-#define xchg(ptr, v) \
- __xchg((v), (ptr), sizeof(*ptr))
-
-#define __HAVE_ARCH_CMPXCHG 1
-
-/*
- * 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) \
+#define cmpxchg64_local(ptr, o, n) \
({ \
- __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; \
- } \
- case 8: \
- { \
- volatile u64 *__ptr = (volatile u64 *)(ptr); \
- asm volatile(lock "cmpxchgq %2,%1" \
- : "=a" (__ret), "+m" (*__ptr) \
- : "r" (__new), "0" (__old) \
- : "memory"); \
- break; \
- } \
- default: \
- __cmpxchg_wrong_size(); \
- } \
- __ret; \
+ BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
+ cmpxchg_local((ptr), (o), (n)); \
})
-#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), "")
-
-#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))
-
-#define cmpxchg64(ptr, o, n) \
+#define cmpxchg16b(ptr, o1, o2, n1, n2) \
+({ \
+ char __ret; \
+ __typeof__(o2) __junk; \
+ __typeof__(*(ptr)) __old1 = (o1); \
+ __typeof__(o2) __old2 = (o2); \
+ __typeof__(*(ptr)) __new1 = (n1); \
+ __typeof__(o2) __new2 = (n2); \
+ asm volatile(LOCK_PREFIX "cmpxchg16b %2;setz %1" \
+ : "=d"(__junk), "=a"(__ret), "+m" (*ptr) \
+ : "b"(__new1), "c"(__new2), \
+ "a"(__old1), "d"(__old2)); \
+ __ret; })
+
+
+#define cmpxchg16b_local(ptr, o1, o2, n1, n2) \
+({ \
+ char __ret; \
+ __typeof__(o2) __junk; \
+ __typeof__(*(ptr)) __old1 = (o1); \
+ __typeof__(o2) __old2 = (o2); \
+ __typeof__(*(ptr)) __new1 = (n1); \
+ __typeof__(o2) __new2 = (n2); \
+ asm volatile("cmpxchg16b %2;setz %1" \
+ : "=d"(__junk), "=a"(__ret), "+m" (*ptr) \
+ : "b"(__new1), "c"(__new2), \
+ "a"(__old1), "d"(__old2)); \
+ __ret; })
+
+#define cmpxchg_double(ptr, o1, o2, n1, n2) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
- cmpxchg((ptr), (o), (n)); \
+ VM_BUG_ON((unsigned long)(ptr) % 16); \
+ cmpxchg16b((ptr), (o1), (o2), (n1), (n2)); \
})
-#define cmpxchg64_local(ptr, o, n) \
+#define cmpxchg_double_local(ptr, o1, o2, n1, n2) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
- cmpxchg_local((ptr), (o), (n)); \
+ VM_BUG_ON((unsigned long)(ptr) % 16); \
+ cmpxchg16b_local((ptr), (o1), (o2), (n1), (n2)); \
})
+#define system_has_cmpxchg_double() cpu_has_cx16
+
#endif /* _ASM_X86_CMPXCHG_64_H */