xref: /openbmc/linux/arch/sparc/include/asm/atomic_64.h (revision 2eb5f31b)
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)
34 ATOMIC_OPS(sub)
35 
36 ATOMIC_OP(and)
37 ATOMIC_OP(or)
38 ATOMIC_OP(xor)
39 
40 #undef ATOMIC_OPS
41 #undef ATOMIC_OP_RETURN
42 #undef ATOMIC_OP
43 
44 #define atomic_dec_return(v)   atomic_sub_return(1, v)
45 #define atomic64_dec_return(v) atomic64_sub_return(1, v)
46 
47 #define atomic_inc_return(v)   atomic_add_return(1, v)
48 #define atomic64_inc_return(v) atomic64_add_return(1, v)
49 
50 /*
51  * atomic_inc_and_test - increment and test
52  * @v: pointer of type atomic_t
53  *
54  * Atomically increments @v by 1
55  * and returns true if the result is zero, or false for all
56  * other cases.
57  */
58 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
59 #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
60 
61 #define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
62 #define atomic64_sub_and_test(i, v) (atomic64_sub_return(i, v) == 0)
63 
64 #define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)
65 #define atomic64_dec_and_test(v) (atomic64_sub_return(1, v) == 0)
66 
67 #define atomic_inc(v) atomic_add(1, v)
68 #define atomic64_inc(v) atomic64_add(1, v)
69 
70 #define atomic_dec(v) atomic_sub(1, v)
71 #define atomic64_dec(v) atomic64_sub(1, v)
72 
73 #define atomic_add_negative(i, v) (atomic_add_return(i, v) < 0)
74 #define atomic64_add_negative(i, v) (atomic64_add_return(i, v) < 0)
75 
76 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
77 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
78 
79 static inline int __atomic_add_unless(atomic_t *v, int a, int u)
80 {
81 	int c, old;
82 	c = atomic_read(v);
83 	for (;;) {
84 		if (unlikely(c == (u)))
85 			break;
86 		old = atomic_cmpxchg((v), c, c + (a));
87 		if (likely(old == c))
88 			break;
89 		c = old;
90 	}
91 	return c;
92 }
93 
94 #define atomic64_cmpxchg(v, o, n) \
95 	((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
96 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
97 
98 static inline long atomic64_add_unless(atomic64_t *v, long a, long u)
99 {
100 	long c, old;
101 	c = atomic64_read(v);
102 	for (;;) {
103 		if (unlikely(c == (u)))
104 			break;
105 		old = atomic64_cmpxchg((v), c, c + (a));
106 		if (likely(old == c))
107 			break;
108 		c = old;
109 	}
110 	return c != (u);
111 }
112 
113 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
114 
115 long atomic64_dec_if_positive(atomic64_t *v);
116 
117 #endif /* !(__ARCH_SPARC64_ATOMIC__) */
118