diff options
Diffstat (limited to 'arch/sh/include/asm/cmpxchg.h')
-rw-r--r-- | arch/sh/include/asm/cmpxchg.h | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/sh/include/asm/cmpxchg.h b/arch/sh/include/asm/cmpxchg.h new file mode 100644 index 000000000..f6bd1406b --- /dev/null +++ b/arch/sh/include/asm/cmpxchg.h @@ -0,0 +1,70 @@ +#ifndef __ASM_SH_CMPXCHG_H +#define __ASM_SH_CMPXCHG_H + +/* + * Atomic operations that C can't guarantee us. Useful for + * resource counting etc.. + */ + +#include <linux/compiler.h> +#include <linux/types.h> + +#if defined(CONFIG_GUSA_RB) +#include <asm/cmpxchg-grb.h> +#elif defined(CONFIG_CPU_SH4A) +#include <asm/cmpxchg-llsc.h> +#else +#include <asm/cmpxchg-irq.h> +#endif + +extern void __xchg_called_with_bad_pointer(void); + +#define __xchg(ptr, x, size) \ +({ \ + unsigned long __xchg__res; \ + volatile void *__xchg_ptr = (ptr); \ + switch (size) { \ + case 4: \ + __xchg__res = xchg_u32(__xchg_ptr, x); \ + break; \ + case 1: \ + __xchg__res = xchg_u8(__xchg_ptr, x); \ + break; \ + default: \ + __xchg_called_with_bad_pointer(); \ + __xchg__res = x; \ + break; \ + } \ + \ + __xchg__res; \ +}) + +#define xchg(ptr,x) \ + ((__typeof__(*(ptr)))__xchg((ptr),(unsigned long)(x), sizeof(*(ptr)))) + +/* This function doesn't exist, so you'll get a linker error + * if something tries to do an invalid cmpxchg(). */ +extern void __cmpxchg_called_with_bad_pointer(void); + +#define __HAVE_ARCH_CMPXCHG 1 + +static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old, + unsigned long new, int size) +{ + switch (size) { + case 4: + return __cmpxchg_u32(ptr, old, new); + } + __cmpxchg_called_with_bad_pointer(); + return old; +} + +#define cmpxchg(ptr,o,n) \ + ({ \ + __typeof__(*(ptr)) _o_ = (o); \ + __typeof__(*(ptr)) _n_ = (n); \ + (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \ + (unsigned long)_n_, sizeof(*(ptr))); \ + }) + +#endif /* __ASM_SH_CMPXCHG_H */ |