diff options
Diffstat (limited to 'arch/arm/include')
-rw-r--r-- | arch/arm/include/asm/cmpxchg.h | 73 |
1 files changed, 13 insertions, 60 deletions
diff --git a/arch/arm/include/asm/cmpxchg.h b/arch/arm/include/asm/cmpxchg.h index d41d7cb..7eb18c1 100644 --- a/arch/arm/include/asm/cmpxchg.h +++ b/arch/arm/include/asm/cmpxchg.h @@ -229,66 +229,19 @@ static inline unsigned long __cmpxchg_local(volatile void *ptr, (unsigned long)(n), \ sizeof(*(ptr)))) -#ifndef CONFIG_CPU_V6 /* min ARCH >= ARMv6K */ - -/* - * Note : ARMv7-M (currently unsupported by Linux) does not support - * ldrexd/strexd. If ARMv7-M is ever supported by the Linux kernel, it should - * not be allowed to use __cmpxchg64. - */ -static inline unsigned long long __cmpxchg64(volatile void *ptr, - unsigned long long old, - unsigned long long new) -{ - register unsigned long long oldval asm("r0"); - register unsigned long long __old asm("r2") = old; - register unsigned long long __new asm("r4") = new; - unsigned long res; - - do { - asm volatile( - " @ __cmpxchg8\n" - " ldrexd %1, %H1, [%2]\n" - " mov %0, #0\n" - " teq %1, %3\n" - " teqeq %H1, %H3\n" - " strexdeq %0, %4, %H4, [%2]\n" - : "=&r" (res), "=&r" (oldval) - : "r" (ptr), "Ir" (__old), "r" (__new) - : "memory", "cc"); - } while (res); - - return oldval; -} - -static inline unsigned long long __cmpxchg64_mb(volatile void *ptr, - unsigned long long old, - unsigned long long new) -{ - unsigned long long ret; - - smp_mb(); - ret = __cmpxchg64(ptr, old, new); - smp_mb(); - - return ret; -} - -#define cmpxchg64(ptr,o,n) \ - ((__typeof__(*(ptr)))__cmpxchg64_mb((ptr), \ - (unsigned long long)(o), \ - (unsigned long long)(n))) - -#define cmpxchg64_local(ptr,o,n) \ - ((__typeof__(*(ptr)))__cmpxchg64((ptr), \ - (unsigned long long)(o), \ - (unsigned long long)(n))) - -#else /* min ARCH = ARMv6 */ - -#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) - -#endif +#define cmpxchg64(ptr, o, n) \ + ((__typeof__(*(ptr)))atomic64_cmpxchg(container_of((ptr), \ + atomic64_t, \ + counter), \ + (unsigned long)(o), \ + (unsigned long)(n))) + +#define cmpxchg64_local(ptr, o, n) \ + ((__typeof__(*(ptr)))local64_cmpxchg(container_of((ptr), \ + local64_t, \ + a), \ + (unsigned long)(o), \ + (unsigned long)(n))) #endif /* __LINUX_ARM_ARCH__ >= 6 */ |