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15#ifndef __ASM_GENERIC_ATOMIC_H
16#define __ASM_GENERIC_ATOMIC_H
17
18#include <asm/cmpxchg.h>
19#include <asm/barrier.h>
20
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37
38#ifdef CONFIG_SMP
39
40
41
42#define ATOMIC_OP(op, c_op) \
43static inline void atomic_##op(int i, atomic_t *v) \
44{ \
45 int c, old; \
46 \
47 c = v->counter; \
48 while ((old = cmpxchg(&v->counter, c, c c_op i)) != c) \
49 c = old; \
50}
51
52#define ATOMIC_OP_RETURN(op, c_op) \
53static inline int atomic_##op##_return(int i, atomic_t *v) \
54{ \
55 int c, old; \
56 \
57 c = v->counter; \
58 while ((old = cmpxchg(&v->counter, c, c c_op i)) != c) \
59 c = old; \
60 \
61 return c c_op i; \
62}
63
64#else
65
66#include <linux/irqflags.h>
67
68#define ATOMIC_OP(op, c_op) \
69static inline void atomic_##op(int i, atomic_t *v) \
70{ \
71 unsigned long flags; \
72 \
73 raw_local_irq_save(flags); \
74 v->counter = v->counter c_op i; \
75 raw_local_irq_restore(flags); \
76}
77
78#define ATOMIC_OP_RETURN(op, c_op) \
79static inline int atomic_##op##_return(int i, atomic_t *v) \
80{ \
81 unsigned long flags; \
82 int ret; \
83 \
84 raw_local_irq_save(flags); \
85 ret = (v->counter = v->counter c_op i); \
86 raw_local_irq_restore(flags); \
87 \
88 return ret; \
89}
90
91#endif
92
93#ifndef atomic_add_return
94ATOMIC_OP_RETURN(add, +)
95#endif
96
97#ifndef atomic_sub_return
98ATOMIC_OP_RETURN(sub, -)
99#endif
100
101#ifndef atomic_clear_mask
102ATOMIC_OP(and, &)
103#define atomic_clear_mask(i, v) atomic_and(~(i), (v))
104#endif
105
106#ifndef atomic_set_mask
107#define CONFIG_ARCH_HAS_ATOMIC_OR
108ATOMIC_OP(or, |)
109#define atomic_set_mask(i, v) atomic_or((i), (v))
110#endif
111
112#undef ATOMIC_OP_RETURN
113#undef ATOMIC_OP
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118
119
120#define ATOMIC_INIT(i) { (i) }
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127
128#ifndef atomic_read
129#define atomic_read(v) ACCESS_ONCE((v)->counter)
130#endif
131
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138
139#define atomic_set(v, i) (((v)->counter) = (i))
140
141#include <linux/irqflags.h>
142
143static inline int atomic_add_negative(int i, atomic_t *v)
144{
145 return atomic_add_return(i, v) < 0;
146}
147
148static inline void atomic_add(int i, atomic_t *v)
149{
150 atomic_add_return(i, v);
151}
152
153static inline void atomic_sub(int i, atomic_t *v)
154{
155 atomic_sub_return(i, v);
156}
157
158static inline void atomic_inc(atomic_t *v)
159{
160 atomic_add_return(1, v);
161}
162
163static inline void atomic_dec(atomic_t *v)
164{
165 atomic_sub_return(1, v);
166}
167
168#define atomic_dec_return(v) atomic_sub_return(1, (v))
169#define atomic_inc_return(v) atomic_add_return(1, (v))
170
171#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
172#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)
173#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
174
175#define atomic_xchg(ptr, v) (xchg(&(ptr)->counter, (v)))
176#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new)))
177
178static inline int __atomic_add_unless(atomic_t *v, int a, int u)
179{
180 int c, old;
181 c = atomic_read(v);
182 while (c != u && (old = atomic_cmpxchg(v, c, c + a)) != c)
183 c = old;
184 return c;
185}
186
187#endif
188