1 /* $Id: atomic.h,v 1.3 2001/07/25 16:15:19 bjornw Exp $ */
3 #ifndef __ASM_CRIS_ATOMIC__
4 #define __ASM_CRIS_ATOMIC__
6 #include <asm/system.h>
7 #include <asm/arch/atomic.h>
8 #include <linux/compiler.h>
11 * Atomic operations that C can't guarantee us. Useful for
12 * resource counting etc..
15 typedef struct { volatile int counter; } atomic_t;
17 #define ATOMIC_INIT(i) { (i) }
19 #define atomic_read(v) ((v)->counter)
20 #define atomic_set(v,i) (((v)->counter) = (i))
22 /* These should be written in asm but we do it in C for now. */
24 static inline void atomic_add(int i, volatile atomic_t *v)
27 cris_atomic_save(v, flags);
29 cris_atomic_restore(v, flags);
32 static inline void atomic_sub(int i, volatile atomic_t *v)
35 cris_atomic_save(v, flags);
37 cris_atomic_restore(v, flags);
40 static inline int atomic_add_return(int i, volatile atomic_t *v)
44 cris_atomic_save(v, flags);
45 retval = (v->counter += i);
46 cris_atomic_restore(v, flags);
50 #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
52 static inline int atomic_sub_return(int i, volatile atomic_t *v)
56 cris_atomic_save(v, flags);
57 retval = (v->counter -= i);
58 cris_atomic_restore(v, flags);
62 static inline int atomic_sub_and_test(int i, volatile atomic_t *v)
66 cris_atomic_save(v, flags);
67 retval = (v->counter -= i) == 0;
68 cris_atomic_restore(v, flags);
72 static inline void atomic_inc(volatile atomic_t *v)
75 cris_atomic_save(v, flags);
77 cris_atomic_restore(v, flags);
80 static inline void atomic_dec(volatile atomic_t *v)
83 cris_atomic_save(v, flags);
85 cris_atomic_restore(v, flags);
88 static inline int atomic_inc_return(volatile atomic_t *v)
92 cris_atomic_save(v, flags);
93 retval = (v->counter)++;
94 cris_atomic_restore(v, flags);
98 static inline int atomic_dec_return(volatile atomic_t *v)
102 cris_atomic_save(v, flags);
103 retval = (v->counter)--;
104 cris_atomic_restore(v, flags);
107 static inline int atomic_dec_and_test(volatile atomic_t *v)
111 cris_atomic_save(v, flags);
112 retval = --(v->counter) == 0;
113 cris_atomic_restore(v, flags);
117 static inline int atomic_inc_and_test(volatile atomic_t *v)
121 cris_atomic_save(v, flags);
122 retval = ++(v->counter) == 0;
123 cris_atomic_restore(v, flags);
127 static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
132 cris_atomic_save(v, flags);
134 if (likely(ret == old))
136 cris_atomic_restore(v, flags);
140 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
142 static inline int atomic_add_unless(atomic_t *v, int a, int u)
147 cris_atomic_save(v, flags);
151 cris_atomic_restore(v, flags);
154 #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
156 /* Atomic operations are already serializing */
157 #define smp_mb__before_atomic_dec() barrier()
158 #define smp_mb__after_atomic_dec() barrier()
159 #define smp_mb__before_atomic_inc() barrier()
160 #define smp_mb__after_atomic_inc() barrier()
162 #include <asm-generic/atomic.h>