1 /* SPDX-License-Identifier: GPL-2.0 */ 1
2 /* 32-bit atomic xchg() and cmpxchg() definiti
3 *
4 * Copyright (C) 1996 David S. Miller (davem@d
5 * Copyright (C) 2000 Anton Blanchard (anton@l
6 * Copyright (C) 2007 Kyle McMartin (kyle@pari
7 *
8 * Additions by Keith M Wesolowski (wesolows@f
9 * on asm-parisc/atomic.h Copyright (C) 2000 P
10 */
11
12 #ifndef __ARCH_SPARC_CMPXCHG__
13 #define __ARCH_SPARC_CMPXCHG__
14
15 unsigned long __xchg_u32(volatile u32 *m, u32
16 void __xchg_called_with_bad_pointer(void);
17
18 static __always_inline unsigned long __arch_xc
19 {
20 switch (size) {
21 case 4:
22 return __xchg_u32(ptr, x);
23 }
24 __xchg_called_with_bad_pointer();
25 return x;
26 }
27
28 #define arch_xchg(ptr,x) ({(__typeof__(*(ptr))
29
30 /* Emulate cmpxchg() the same way we emulate a
31 * by hashing the object address and indexing
32 * of spinlocks to get a bit of performance...
33 *
34 * See arch/sparc/lib/atomic32.c for implement
35 *
36 * Cribbed from <asm-parisc/atomic.h>
37 */
38
39 /* bug catcher for when unsupported size is us
40 void __cmpxchg_called_with_bad_pointer(void);
41 u8 __cmpxchg_u8(volatile u8 *m, u8 old, u8 new
42 u16 __cmpxchg_u16(volatile u16 *m, u16 old, u1
43 u32 __cmpxchg_u32(volatile u32 *m, u32 old, u3
44
45 /* don't worry...optimizer will get rid of mos
46 static inline unsigned long
47 __cmpxchg(volatile void *ptr, unsigned long ol
48 {
49 return
50 size == 1 ? __cmpxchg_u8(ptr,
51 size == 2 ? __cmpxchg_u16(ptr,
52 size == 4 ? __cmpxchg_u32(ptr,
53 (__cmpxchg_called_with
54 }
55
56 #define arch_cmpxchg(ptr, o, n)
57 ({
58 __typeof__(*(ptr)) _o_ = (o);
59 __typeof__(*(ptr)) _n_ = (n);
60 (__typeof__(*(ptr))) __cmpxchg((ptr),
61 (unsigned long)_n_, si
62 })
63
64 u64 __cmpxchg_u64(volatile u64 *ptr, u64 old,
65 #define arch_cmpxchg64(ptr, old, new) __cmpx
66
67 #include <asm-generic/cmpxchg-local.h>
68
69 /*
70 * cmpxchg_local and cmpxchg64_local are atomi
71 * them available.
72 */
73 #define arch_cmpxchg_local(ptr, o, n)
74 ((__typeof__(*(ptr)))__generic_cmpxchg
75 (unsigned long)(n), si
76 #define arch_cmpxchg64_local(ptr, o, n) __gene
77
78 #endif /* __ARCH_SPARC_CMPXCHG__ */
79
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