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1/* $Id: atomic.h,v 1.3 2001/07/25 16:15:19 bjornw Exp $ */
2
3#ifndef __ASM_CRIS_ATOMIC__
4#define __ASM_CRIS_ATOMIC__
5
6#include <linux/compiler.h>
7
8#include <asm/system.h>
9#include <asm/arch/atomic.h>
10
11/*
12 * Atomic operations that C can't guarantee us. Useful for
13 * resource counting etc..
14 */
15
16typedef struct { volatile int counter; } atomic_t;
17
18#define ATOMIC_INIT(i) { (i) }
19
20#define atomic_read(v) ((v)->counter)
21#define atomic_set(v,i) (((v)->counter) = (i))
22
23/* These should be written in asm but we do it in C for now. */
24
25static inline void atomic_add(int i, volatile atomic_t *v)
26{
27 unsigned long flags;
28 cris_atomic_save(v, flags);
29 v->counter += i;
30 cris_atomic_restore(v, flags);
31}
32
33static inline void atomic_sub(int i, volatile atomic_t *v)
34{
35 unsigned long flags;
36 cris_atomic_save(v, flags);
37 v->counter -= i;
38 cris_atomic_restore(v, flags);
39}
40
41static inline int atomic_add_return(int i, volatile atomic_t *v)
42{
43 unsigned long flags;
44 int retval;
45 cris_atomic_save(v, flags);
46 retval = (v->counter += i);
47 cris_atomic_restore(v, flags);
48 return retval;
49}
50
51#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
52
53static inline int atomic_sub_return(int i, volatile atomic_t *v)
54{
55 unsigned long flags;
56 int retval;
57 cris_atomic_save(v, flags);
58 retval = (v->counter -= i);
59 cris_atomic_restore(v, flags);
60 return retval;
61}
62
63static inline int atomic_sub_and_test(int i, volatile atomic_t *v)
64{
65 int retval;
66 unsigned long flags;
67 cris_atomic_save(v, flags);
68 retval = (v->counter -= i) == 0;
69 cris_atomic_restore(v, flags);
70 return retval;
71}
72
73static inline void atomic_inc(volatile atomic_t *v)
74{
75 unsigned long flags;
76 cris_atomic_save(v, flags);
77 (v->counter)++;
78 cris_atomic_restore(v, flags);
79}
80
81static inline void atomic_dec(volatile atomic_t *v)
82{
83 unsigned long flags;
84 cris_atomic_save(v, flags);
85 (v->counter)--;
86 cris_atomic_restore(v, flags);
87}
88
89static inline int atomic_inc_return(volatile atomic_t *v)
90{
91 unsigned long flags;
92 int retval;
93 cris_atomic_save(v, flags);
94 retval = ++(v->counter);
95 cris_atomic_restore(v, flags);
96 return retval;
97}
98
99static inline int atomic_dec_return(volatile atomic_t *v)
100{
101 unsigned long flags;
102 int retval;
103 cris_atomic_save(v, flags);
104 retval = --(v->counter);
105 cris_atomic_restore(v, flags);
106 return retval;
107}
108static inline int atomic_dec_and_test(volatile atomic_t *v)
109{
110 int retval;
111 unsigned long flags;
112 cris_atomic_save(v, flags);
113 retval = --(v->counter) == 0;
114 cris_atomic_restore(v, flags);
115 return retval;
116}
117
118static inline int atomic_inc_and_test(volatile atomic_t *v)
119{
120 int retval;
121 unsigned long flags;
122 cris_atomic_save(v, flags);
123 retval = ++(v->counter) == 0;
124 cris_atomic_restore(v, flags);
125 return retval;
126}
127
128static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
129{
130 int ret;
131 unsigned long flags;
132
133 cris_atomic_save(v, flags);
134 ret = v->counter;
135 if (likely(ret == old))
136 v->counter = new;
137 cris_atomic_restore(v, flags);
138 return ret;
139}
140
141#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
142
143static inline int atomic_add_unless(atomic_t *v, int a, int u)
144{
145 int ret;
146 unsigned long flags;
147
148 cris_atomic_save(v, flags);
149 ret = v->counter;
150 if (ret != u)
151 v->counter += a;
152 cris_atomic_restore(v, flags);
153 return ret != u;
154}
155#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
156
157/* Atomic operations are already serializing */
158#define smp_mb__before_atomic_dec() barrier()
159#define smp_mb__after_atomic_dec() barrier()
160#define smp_mb__before_atomic_inc() barrier()
161#define smp_mb__after_atomic_inc() barrier()
162
163#include <asm-generic/atomic.h>
164#endif