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 #include <linux/types.h>
8 #include <asm/system.h>
9 #include <arch/atomic.h>
10
11 /*
12 * Atomic operations that C can't guarantee us. Useful for
13 * resource counting etc..
14 */
15
16 #define ATOMIC_INIT(i) { (i) }
17
18 #define atomic_read(v) (*(volatile int *)&(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
atomic_add(int i,volatile atomic_t * v)23 static 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
atomic_sub(int i,volatile atomic_t * v)31 static 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
atomic_add_return(int i,volatile atomic_t * v)39 static 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
atomic_sub_return(int i,volatile atomic_t * v)51 static 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
atomic_sub_and_test(int i,volatile atomic_t * v)61 static 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
atomic_inc(volatile atomic_t * v)71 static 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
atomic_dec(volatile atomic_t * v)79 static 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
atomic_inc_return(volatile atomic_t * v)87 static 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
atomic_dec_return(volatile atomic_t * v)97 static 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 }
atomic_dec_and_test(volatile atomic_t * v)106 static 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
atomic_inc_and_test(volatile atomic_t * v)116 static 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
atomic_cmpxchg(atomic_t * v,int old,int new)126 static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
127 {
128 int ret;
129 unsigned long flags;
130
131 cris_atomic_save(v, flags);
132 ret = v->counter;
133 if (likely(ret == old))
134 v->counter = new;
135 cris_atomic_restore(v, flags);
136 return ret;
137 }
138
139 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
140
__atomic_add_unless(atomic_t * v,int a,int u)141 static inline int __atomic_add_unless(atomic_t *v, int a, int u)
142 {
143 int ret;
144 unsigned long flags;
145
146 cris_atomic_save(v, flags);
147 ret = v->counter;
148 if (ret != u)
149 v->counter += a;
150 cris_atomic_restore(v, flags);
151 return ret;
152 }
153
154 /* Atomic operations are already serializing */
155 #define smp_mb__before_atomic_dec() barrier()
156 #define smp_mb__after_atomic_dec() barrier()
157 #define smp_mb__before_atomic_inc() barrier()
158 #define smp_mb__after_atomic_inc() barrier()
159
160 #endif
161