1 /* 64-bit atomic xchg() and cmpxchg() definitions.
3 * Copyright (C) 1996, 1997, 2000 David S. Miller (davem@redhat.com)
6 #ifndef __ARCH_SPARC64_CMPXCHG__
7 #define __ARCH_SPARC64_CMPXCHG__
9 static inline unsigned long xchg32(__volatile__
unsigned int *m
, unsigned int val
)
11 unsigned long tmp1
, tmp2
;
18 " bne,a,pn %%icc, 1b\n"
20 : "=&r" (val
), "=&r" (tmp1
), "=&r" (tmp2
)
26 static inline unsigned long xchg64(__volatile__
unsigned long *m
, unsigned long val
)
28 unsigned long tmp1
, tmp2
;
33 " casx [%4], %2, %0\n"
35 " bne,a,pn %%xcc, 1b\n"
37 : "=&r" (val
), "=&r" (tmp1
), "=&r" (tmp2
)
43 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
45 extern void __xchg_called_with_bad_pointer(void);
47 static inline unsigned long __xchg(unsigned long x
, __volatile__
void * ptr
,
52 return xchg32(ptr
, x
);
54 return xchg64(ptr
, x
);
56 __xchg_called_with_bad_pointer();
61 * Atomic compare and exchange. Compare OLD with MEM, if identical,
62 * store NEW in MEM. Return the initial value in MEM. Success is
63 * indicated by comparing RETURN with OLD.
66 #include <asm-generic/cmpxchg-local.h>
68 #define __HAVE_ARCH_CMPXCHG 1
70 static inline unsigned long
71 __cmpxchg_u32(volatile int *m
, int old
, int new)
73 __asm__
__volatile__("cas [%2], %3, %0"
75 : "0" (new), "r" (m
), "r" (old
)
81 static inline unsigned long
82 __cmpxchg_u64(volatile long *m
, unsigned long old
, unsigned long new)
84 __asm__
__volatile__("casx [%2], %3, %0"
86 : "0" (new), "r" (m
), "r" (old
)
92 /* This function doesn't exist, so you'll get a linker error
93 if something tries to do an invalid cmpxchg(). */
94 extern void __cmpxchg_called_with_bad_pointer(void);
96 static inline unsigned long
97 __cmpxchg(volatile void *ptr
, unsigned long old
, unsigned long new, int size
)
101 return __cmpxchg_u32(ptr
, old
, new);
103 return __cmpxchg_u64(ptr
, old
, new);
105 __cmpxchg_called_with_bad_pointer();
109 #define cmpxchg(ptr,o,n) \
111 __typeof__(*(ptr)) _o_ = (o); \
112 __typeof__(*(ptr)) _n_ = (n); \
113 (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
114 (unsigned long)_n_, sizeof(*(ptr))); \
118 * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
122 static inline unsigned long __cmpxchg_local(volatile void *ptr
,
124 unsigned long new, int size
)
128 case 8: return __cmpxchg(ptr
, old
, new, size
);
130 return __cmpxchg_local_generic(ptr
, old
, new, size
);
136 #define cmpxchg_local(ptr, o, n) \
137 ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
138 (unsigned long)(n), sizeof(*(ptr))))
139 #define cmpxchg64_local(ptr, o, n) \
141 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
142 cmpxchg_local((ptr), (o), (n)); \
144 #define cmpxchg64(ptr, o, n) cmpxchg64_local((ptr), (o), (n))
146 #endif /* __ARCH_SPARC64_CMPXCHG__ */