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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 <asm/system.h>
7#include <asm/arch/atomic.h>
8
9/*
10 * Atomic operations that C can't guarantee us. Useful for
11 * resource counting etc..
12 */
13
14typedef struct { volatile int counter; } atomic_t;
15
16#define ATOMIC_INIT(i) { (i) }
17
18#define atomic_read(v) ((v)->counter)
19#define atomic_set(v,i) (((v)->counter) = (i))
20
21/* These should be written in asm but we do it in C for now. */
22
23static inline void atomic_add(int i, volatile atomic_t *v)
24{
25 unsigned long flags;
26 cris_atomic_save(v, flags);
27 v->counter += i;
28 cris_atomic_restore(v, flags);
29}
30
31static inline void atomic_sub(int i, volatile atomic_t *v)
32{
33 unsigned long flags;
34 cris_atomic_save(v, flags);
35 v->counter -= i;
36 cris_atomic_restore(v, flags);
37}
38
39static inline int atomic_add_return(int i, volatile atomic_t *v)
40{
41 unsigned long flags;
42 int retval;
43 cris_atomic_save(v, flags);
44 retval = (v->counter += i);
45 cris_atomic_restore(v, flags);
46 return retval;
47}
48
49#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
50
51static inline int atomic_sub_return(int i, volatile atomic_t *v)
52{
53 unsigned long flags;
54 int retval;
55 cris_atomic_save(v, flags);
56 retval = (v->counter -= i);
57 cris_atomic_restore(v, flags);
58 return retval;
59}
60
61static inline int atomic_sub_and_test(int i, volatile atomic_t *v)
62{
63 int retval;
64 unsigned long flags;
65 cris_atomic_save(v, flags);
66 retval = (v->counter -= i) == 0;
67 cris_atomic_restore(v, flags);
68 return retval;
69}
70
71static inline void atomic_inc(volatile atomic_t *v)
72{
73 unsigned long flags;
74 cris_atomic_save(v, flags);
75 (v->counter)++;
76 cris_atomic_restore(v, flags);
77}
78
79static inline void atomic_dec(volatile atomic_t *v)
80{
81 unsigned long flags;
82 cris_atomic_save(v, flags);
83 (v->counter)--;
84 cris_atomic_restore(v, flags);
85}
86
87static inline int atomic_inc_return(volatile atomic_t *v)
88{
89 unsigned long flags;
90 int retval;
91 cris_atomic_save(v, flags);
92 retval = (v->counter)++;
93 cris_atomic_restore(v, flags);
94 return retval;
95}
96
97static inline int atomic_dec_return(volatile atomic_t *v)
98{
99 unsigned long flags;
100 int retval;
101 cris_atomic_save(v, flags);
102 retval = (v->counter)--;
103 cris_atomic_restore(v, flags);
104 return retval;
105}
106static inline int atomic_dec_and_test(volatile atomic_t *v)
107{
108 int retval;
109 unsigned long flags;
110 cris_atomic_save(v, flags);
111 retval = --(v->counter) == 0;
112 cris_atomic_restore(v, flags);
113 return retval;
114}
115
116static inline int atomic_inc_and_test(volatile atomic_t *v)
117{
118 int retval;
119 unsigned long flags;
120 cris_atomic_save(v, flags);
121 retval = ++(v->counter) == 0;
122 cris_atomic_restore(v, flags);
123 return retval;
124}
125
126/* Atomic operations are already serializing */
127#define smp_mb__before_atomic_dec() barrier()
128#define smp_mb__after_atomic_dec() barrier()
129#define smp_mb__before_atomic_inc() barrier()
130#define smp_mb__after_atomic_inc() barrier()
131
132#endif