diff options
Diffstat (limited to 'arch/x86/include/asm/cmpxchg_32.h')
| -rw-r--r-- | arch/x86/include/asm/cmpxchg_32.h | 203 |
1 files changed, 124 insertions, 79 deletions
diff --git a/arch/x86/include/asm/cmpxchg_32.h b/arch/x86/include/asm/cmpxchg_32.h index b5731c51f0..62cef2113c 100644 --- a/arch/x86/include/asm/cmpxchg_32.h +++ b/arch/x86/include/asm/cmpxchg_32.h @@ -3,103 +3,148 @@ #define _ASM_X86_CMPXCHG_32_H /* - * Note: if you use set64_bit(), __cmpxchg64(), or their variants, + * Note: if you use __cmpxchg64(), or their variants, * you need to test for the feature in boot_cpu_data. */ -#ifdef CONFIG_X86_CMPXCHG64 -#define arch_cmpxchg64(ptr, o, n) \ - ((__typeof__(*(ptr)))__cmpxchg64((ptr), (unsigned long long)(o), \ - (unsigned long long)(n))) -#define arch_cmpxchg64_local(ptr, o, n) \ - ((__typeof__(*(ptr)))__cmpxchg64_local((ptr), (unsigned long long)(o), \ - (unsigned long long)(n))) -#define arch_try_cmpxchg64(ptr, po, n) \ - __try_cmpxchg64((ptr), (unsigned long long *)(po), \ - (unsigned long long)(n)) -#endif +union __u64_halves { + u64 full; + struct { + u32 low, high; + }; +}; + +#define __arch_cmpxchg64(_ptr, _old, _new, _lock) \ +({ \ + union __u64_halves o = { .full = (_old), }, \ + n = { .full = (_new), }; \ + \ + asm volatile(_lock "cmpxchg8b %[ptr]" \ + : [ptr] "+m" (*(_ptr)), \ + "+a" (o.low), "+d" (o.high) \ + : "b" (n.low), "c" (n.high) \ + : "memory"); \ + \ + o.full; \ +}) + + +static __always_inline u64 __cmpxchg64(volatile u64 *ptr, u64 old, u64 new) +{ + return __arch_cmpxchg64(ptr, old, new, LOCK_PREFIX); +} -static inline u64 __cmpxchg64(volatile u64 *ptr, u64 old, u64 new) +static __always_inline u64 __cmpxchg64_local(volatile u64 *ptr, u64 old, u64 new) { - u64 prev; - asm volatile(LOCK_PREFIX "cmpxchg8b %1" - : "=A" (prev), - "+m" (*ptr) - : "b" ((u32)new), - "c" ((u32)(new >> 32)), - "0" (old) - : "memory"); - return prev; + return __arch_cmpxchg64(ptr, old, new,); } -static inline u64 __cmpxchg64_local(volatile u64 *ptr, u64 old, u64 new) +#define __arch_try_cmpxchg64(_ptr, _oldp, _new, _lock) \ +({ \ + union __u64_halves o = { .full = *(_oldp), }, \ + n = { .full = (_new), }; \ + bool ret; \ + \ + asm volatile(_lock "cmpxchg8b %[ptr]" \ + CC_SET(e) \ + : CC_OUT(e) (ret), \ + [ptr] "+m" (*(_ptr)), \ + "+a" (o.low), "+d" (o.high) \ + : "b" (n.low), "c" (n.high) \ + : "memory"); \ + \ + if (unlikely(!ret)) \ + *(_oldp) = o.full; \ + \ + likely(ret); \ +}) + +static __always_inline bool __try_cmpxchg64(volatile u64 *ptr, u64 *oldp, u64 new) { - u64 prev; - asm volatile("cmpxchg8b %1" - : "=A" (prev), - "+m" (*ptr) - : "b" ((u32)new), - "c" ((u32)(new >> 32)), - "0" (old) - : "memory"); - return prev; + return __arch_try_cmpxchg64(ptr, oldp, new, LOCK_PREFIX); } -static inline bool __try_cmpxchg64(volatile u64 *ptr, u64 *pold, u64 new) +static __always_inline bool __try_cmpxchg64_local(volatile u64 *ptr, u64 *oldp, u64 new) { - bool success; - u64 old = *pold; - asm volatile(LOCK_PREFIX "cmpxchg8b %[ptr]" - CC_SET(z) - : CC_OUT(z) (success), - [ptr] "+m" (*ptr), - "+A" (old) - : "b" ((u32)new), - "c" ((u32)(new >> 32)) - : "memory"); - - if (unlikely(!success)) - *pold = old; - return success; + return __arch_try_cmpxchg64(ptr, oldp, new,); } -#ifndef CONFIG_X86_CMPXCHG64 +#ifdef CONFIG_X86_CMPXCHG64 + +#define arch_cmpxchg64 __cmpxchg64 + +#define arch_cmpxchg64_local __cmpxchg64_local + +#define arch_try_cmpxchg64 __try_cmpxchg64 + +#define arch_try_cmpxchg64_local __try_cmpxchg64_local + +#else + /* * Building a kernel capable running on 80386 and 80486. It may be necessary * to simulate the cmpxchg8b on the 80386 and 80486 CPU. */ -#define arch_cmpxchg64(ptr, o, n) \ -({ \ - __typeof__(*(ptr)) __ret; \ - __typeof__(*(ptr)) __old = (o); \ - __typeof__(*(ptr)) __new = (n); \ - alternative_io(LOCK_PREFIX_HERE \ - "call cmpxchg8b_emu", \ - "lock; cmpxchg8b (%%esi)" , \ - X86_FEATURE_CX8, \ - "=A" (__ret), \ - "S" ((ptr)), "0" (__old), \ - "b" ((unsigned int)__new), \ - "c" ((unsigned int)(__new>>32)) \ - : "memory"); \ - __ret; }) - - -#define arch_cmpxchg64_local(ptr, o, n) \ -({ \ - __typeof__(*(ptr)) __ret; \ - __typeof__(*(ptr)) __old = (o); \ - __typeof__(*(ptr)) __new = (n); \ - alternative_io("call cmpxchg8b_emu", \ - "cmpxchg8b (%%esi)" , \ - X86_FEATURE_CX8, \ - "=A" (__ret), \ - "S" ((ptr)), "0" (__old), \ - "b" ((unsigned int)__new), \ - "c" ((unsigned int)(__new>>32)) \ - : "memory"); \ - __ret; }) +#define __arch_cmpxchg64_emu(_ptr, _old, _new, _lock_loc, _lock) \ +({ \ + union __u64_halves o = { .full = (_old), }, \ + n = { .full = (_new), }; \ + \ + asm volatile(ALTERNATIVE(_lock_loc \ + "call cmpxchg8b_emu", \ + _lock "cmpxchg8b %a[ptr]", X86_FEATURE_CX8) \ + : "+a" (o.low), "+d" (o.high) \ + : "b" (n.low), "c" (n.high), [ptr] "S" (_ptr) \ + : "memory"); \ + \ + o.full; \ +}) + +static __always_inline u64 arch_cmpxchg64(volatile u64 *ptr, u64 old, u64 new) +{ + return __arch_cmpxchg64_emu(ptr, old, new, LOCK_PREFIX_HERE, "lock; "); +} +#define arch_cmpxchg64 arch_cmpxchg64 + +static __always_inline u64 arch_cmpxchg64_local(volatile u64 *ptr, u64 old, u64 new) +{ + return __arch_cmpxchg64_emu(ptr, old, new, ,); +} +#define arch_cmpxchg64_local arch_cmpxchg64_local + +#define __arch_try_cmpxchg64_emu(_ptr, _oldp, _new, _lock_loc, _lock) \ +({ \ + union __u64_halves o = { .full = *(_oldp), }, \ + n = { .full = (_new), }; \ + bool ret; \ + \ + asm volatile(ALTERNATIVE(_lock_loc \ + "call cmpxchg8b_emu", \ + _lock "cmpxchg8b %a[ptr]", X86_FEATURE_CX8) \ + CC_SET(e) \ + : CC_OUT(e) (ret), \ + "+a" (o.low), "+d" (o.high) \ + : "b" (n.low), "c" (n.high), [ptr] "S" (_ptr) \ + : "memory"); \ + \ + if (unlikely(!ret)) \ + *(_oldp) = o.full; \ + \ + likely(ret); \ +}) + +static __always_inline bool arch_try_cmpxchg64(volatile u64 *ptr, u64 *oldp, u64 new) +{ + return __arch_try_cmpxchg64_emu(ptr, oldp, new, LOCK_PREFIX_HERE, "lock; "); +} +#define arch_try_cmpxchg64 arch_try_cmpxchg64 + +static __always_inline bool arch_try_cmpxchg64_local(volatile u64 *ptr, u64 *oldp, u64 new) +{ + return __arch_try_cmpxchg64_emu(ptr, oldp, new, ,); +} +#define arch_try_cmpxchg64_local arch_try_cmpxchg64_local #endif |