File: /usr/src/linux/include/asm-sparc64/atomic.h

1     /* $Id: atomic.h,v 1.22 2001/07/11 23:56:07 davem Exp $
2      * atomic.h: Thankfully the V9 is at least reasonable for this
3      *           stuff.
4      *
5      * Copyright (C) 1996, 1997, 2000 David S. Miller (davem@redhat.com)
6      */
7     
8     #ifndef __ARCH_SPARC64_ATOMIC__
9     #define __ARCH_SPARC64_ATOMIC__
10     
11     typedef struct { volatile int counter; } atomic_t;
12     #define ATOMIC_INIT(i)	{ (i) }
13     
14     #define atomic_read(v)		((v)->counter)
15     #define atomic_set(v, i)	(((v)->counter) = i)
16     
17     extern int __atomic_add(int, atomic_t *);
18     extern int __atomic_sub(int, atomic_t *);
19     
20     #define atomic_add(i, v) ((void)__atomic_add(i, v))
21     #define atomic_sub(i, v) ((void)__atomic_sub(i, v))
22     
23     #define atomic_dec_return(v) __atomic_sub(1, v)
24     #define atomic_inc_return(v) __atomic_add(1, v)
25     
26     #define atomic_sub_and_test(i, v) (__atomic_sub(i, v) == 0)
27     #define atomic_dec_and_test(v) (__atomic_sub(1, v) == 0)
28     
29     #define atomic_inc(v) ((void)__atomic_add(1, v))
30     #define atomic_dec(v) ((void)__atomic_sub(1, v))
31     
32     /* Atomic operations are already serializing */
33     #define smp_mb__before_atomic_dec()	barrier()
34     #define smp_mb__after_atomic_dec()	barrier()
35     #define smp_mb__before_atomic_inc()	barrier()
36     #define smp_mb__after_atomic_inc()	barrier()
37     
38     #endif /* !(__ARCH_SPARC64_ATOMIC__) */
39