1 /* atomic.h: Thankfully the V9 is at least reasonable for this
2 * stuff.
3 *
4 * Copyright (C) 1996, 1997, 2000, 2012 David S. Miller (davem@redhat.com)
5 */
6
7 #ifndef __ARCH_SPARC64_ATOMIC__
8 #define __ARCH_SPARC64_ATOMIC__
9
10 #include <linux/types.h>
11 #include <asm/cmpxchg.h>
12 #include <asm/barrier.h>
13
14 #define ATOMIC_INIT(i) { (i) }
15 #define ATOMIC64_INIT(i) { (i) }
16
17 #define atomic_read(v) ACCESS_ONCE((v)->counter)
18 #define atomic64_read(v) ACCESS_ONCE((v)->counter)
19
20 #define atomic_set(v, i) (((v)->counter) = i)
21 #define atomic64_set(v, i) (((v)->counter) = i)
22
23 #define ATOMIC_OP(op) \
24 void atomic_##op(int, atomic_t *); \
25 void atomic64_##op(long, atomic64_t *);
26
27 #define ATOMIC_OP_RETURN(op) \
28 int atomic_##op##_return(int, atomic_t *); \
29 long atomic64_##op##_return(long, atomic64_t *);
30
31 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
32
33 ATOMIC_OPS(add)
ATOMIC_OPS(sub)34 ATOMIC_OPS(sub)
35
36 #undef ATOMIC_OPS
37 #undef ATOMIC_OP_RETURN
38 #undef ATOMIC_OP
39
40 #define atomic_dec_return(v) atomic_sub_return(1, v)
41 #define atomic64_dec_return(v) atomic64_sub_return(1, v)
42
43 #define atomic_inc_return(v) atomic_add_return(1, v)
44 #define atomic64_inc_return(v) atomic64_add_return(1, v)
45
46 /*
47 * atomic_inc_and_test - increment and test
48 * @v: pointer of type atomic_t
49 *
50 * Atomically increments @v by 1
51 * and returns true if the result is zero, or false for all
52 * other cases.
53 */
54 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
55 #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
56
57 #define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
58 #define atomic64_sub_and_test(i, v) (atomic64_sub_return(i, v) == 0)
59
60 #define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)
61 #define atomic64_dec_and_test(v) (atomic64_sub_return(1, v) == 0)
62
63 #define atomic_inc(v) atomic_add(1, v)
64 #define atomic64_inc(v) atomic64_add(1, v)
65
66 #define atomic_dec(v) atomic_sub(1, v)
67 #define atomic64_dec(v) atomic64_sub(1, v)
68
69 #define atomic_add_negative(i, v) (atomic_add_return(i, v) < 0)
70 #define atomic64_add_negative(i, v) (atomic64_add_return(i, v) < 0)
71
72 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
73 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
74
75 static inline int __atomic_add_unless(atomic_t *v, int a, int u)
76 {
77 int c, old;
78 c = atomic_read(v);
79 for (;;) {
80 if (unlikely(c == (u)))
81 break;
82 old = atomic_cmpxchg((v), c, c + (a));
83 if (likely(old == c))
84 break;
85 c = old;
86 }
87 return c;
88 }
89
90 #define atomic64_cmpxchg(v, o, n) \
91 ((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
92 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
93
atomic64_add_unless(atomic64_t * v,long a,long u)94 static inline long atomic64_add_unless(atomic64_t *v, long a, long u)
95 {
96 long c, old;
97 c = atomic64_read(v);
98 for (;;) {
99 if (unlikely(c == (u)))
100 break;
101 old = atomic64_cmpxchg((v), c, c + (a));
102 if (likely(old == c))
103 break;
104 c = old;
105 }
106 return c != (u);
107 }
108
109 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
110
111 long atomic64_dec_if_positive(atomic64_t *v);
112
113 #endif /* !(__ARCH_SPARC64_ATOMIC__) */
114