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1/* $Id: atomic.h,v 1.22 2001/07/11 23:56:07 davem Exp $
2 * atomic.h: Thankfully the V9 is at least reasonable for this
3 * stuff.
4 *
5 * Copyright (C) 1996, 1997, 2000 David S. Miller (davem@redhat.com)
6 */
7
8#ifndef __ARCH_SPARC64_ATOMIC__
9#define __ARCH_SPARC64_ATOMIC__
10
11#include <linux/types.h>
12
13typedef struct { volatile int counter; } atomic_t;
14typedef struct { volatile __s64 counter; } atomic64_t;
15
16#define ATOMIC_INIT(i) { (i) }
17#define ATOMIC64_INIT(i) { (i) }
18
19#define atomic_read(v) ((v)->counter)
20#define atomic64_read(v) ((v)->counter)
21
22#define atomic_set(v, i) (((v)->counter) = i)
23#define atomic64_set(v, i) (((v)->counter) = i)
24
25extern void atomic_add(int, atomic_t *);
26extern void atomic64_add(int, atomic64_t *);
27extern void atomic_sub(int, atomic_t *);
28extern void atomic64_sub(int, atomic64_t *);
29
30extern int atomic_add_ret(int, atomic_t *);
31extern int atomic64_add_ret(int, atomic64_t *);
32extern int atomic_sub_ret(int, atomic_t *);
33extern int atomic64_sub_ret(int, atomic64_t *);
34
35#define atomic_dec_return(v) atomic_sub_ret(1, v)
36#define atomic64_dec_return(v) atomic64_sub_ret(1, v)
37
38#define atomic_inc_return(v) atomic_add_ret(1, v)
39#define atomic64_inc_return(v) atomic64_add_ret(1, v)
40
41#define atomic_sub_return(i, v) atomic_sub_ret(i, v)
42#define atomic64_sub_return(i, v) atomic64_sub_ret(i, v)
43
44#define atomic_add_return(i, v) atomic_add_ret(i, v)
45#define atomic64_add_return(i, v) atomic64_add_ret(i, v)
46
47/*
48 * atomic_inc_and_test - increment and test
49 * @v: pointer of type atomic_t
50 *
51 * Atomically increments @v by 1
52 * and returns true if the result is zero, or false for all
53 * other cases.
54 */
55#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
56#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
57
58#define atomic_sub_and_test(i, v) (atomic_sub_ret(i, v) == 0)
59#define atomic64_sub_and_test(i, v) (atomic64_sub_ret(i, v) == 0)
60
61#define atomic_dec_and_test(v) (atomic_sub_ret(1, v) == 0)
62#define atomic64_dec_and_test(v) (atomic64_sub_ret(1, v) == 0)
63
64#define atomic_inc(v) atomic_add(1, v)
65#define atomic64_inc(v) atomic64_add(1, v)
66
67#define atomic_dec(v) atomic_sub(1, v)
68#define atomic64_dec(v) atomic64_sub(1, v)
69
70#define atomic_add_negative(i, v) (atomic_add_ret(i, v) < 0)
71#define atomic64_add_negative(i, v) (atomic64_add_ret(i, v) < 0)
72
73#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
74#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
75
76#define atomic_add_unless(v, a, u) \
77({ \
78 int c, old; \
79 c = atomic_read(v); \
80 for (;;) { \
81 if (unlikely(c == (u))) \
82 break; \
83 old = atomic_cmpxchg((v), c, c + (a)); \
84 if (likely(old == c)) \
85 break; \
86 c = old; \
87 } \
88 likely(c != (u)); \
89})
90#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
91
92/* Atomic operations are already serializing */
93#ifdef CONFIG_SMP
94#define smp_mb__before_atomic_dec() membar_storeload_loadload();
95#define smp_mb__after_atomic_dec() membar_storeload_storestore();
96#define smp_mb__before_atomic_inc() membar_storeload_loadload();
97#define smp_mb__after_atomic_inc() membar_storeload_storestore();
98#else
99#define smp_mb__before_atomic_dec() barrier()
100#define smp_mb__after_atomic_dec() barrier()
101#define smp_mb__before_atomic_inc() barrier()
102#define smp_mb__after_atomic_inc() barrier()
103#endif
104
105#include <asm-generic/atomic.h>
106#endif /* !(__ARCH_SPARC64_ATOMIC__) */