atomic-long.h revision 271127 
1/*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * Copyright (c) 2013, 2014 Mellanox Technologies, Ltd.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice unmodified, this list of conditions, and the following
13 *    disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#ifndef	_ATOMIC_LONG_H_
31#define	_ATOMIC_LONG_H_
32
33#include <sys/cdefs.h>
34#include <sys/types.h>
35#include <machine/atomic.h>
36
37typedef struct {
38	volatile u_long counter;
39} atomic_long_t;
40
41#define	atomic_long_add(i, v)		atomic_long_add_return((i), (v))
42#define	atomic_long_inc_return(v)	atomic_long_add_return(1, (v))
43
44static inline long
45atomic_long_add_return(long i, atomic_long_t *v)
46{
47	return i + atomic_fetchadd_long(&v->counter, i);
48}
49
50static inline void
51atomic_long_set(atomic_long_t *v, long i)
52{
53	atomic_store_rel_long(&v->counter, i);
54}
55
56static inline long
57atomic_long_read(atomic_long_t *v)
58{
59	return atomic_load_acq_long(&v->counter);
60}
61
62static inline long
63atomic_long_inc(atomic_long_t *v)
64{
65	return atomic_fetchadd_long(&v->counter, 1) + 1;
66}
67
68static inline long
69atomic_long_dec(atomic_long_t *v)
70{
71	return atomic_fetchadd_long(&v->counter, -1) - 1;
72}
73
74static inline long
75atomic_long_dec_and_test(atomic_long_t *v)
76{
77	long i = atomic_long_add(-1, v);
78	return i == 0 ;
79}
80
81#endif	/* _ATOMIC_LONG_H_ */
82