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 | * $FreeBSD$ |
---|
30 | */ |
---|
31 | #ifndef _ASM_ATOMIC_H_ |
---|
32 | #define _ASM_ATOMIC_H_ |
---|
33 | |
---|
34 | #include <sys/cdefs.h> |
---|
35 | #include <sys/types.h> |
---|
36 | #include <machine/atomic.h> |
---|
37 | |
---|
38 | typedef struct { |
---|
39 | volatile u_int counter; |
---|
40 | } atomic_t; |
---|
41 | |
---|
42 | #define ATOMIC_INIT(v) { (v) } |
---|
43 | |
---|
44 | #define atomic_add(i, v) atomic_add_return((i), (v)) |
---|
45 | #define atomic_sub(i, v) atomic_sub_return((i), (v)) |
---|
46 | #define atomic_inc_return(v) atomic_add_return(1, (v)) |
---|
47 | #define atomic_add_negative(i, v) (atomic_add_return((i), (v)) < 0) |
---|
48 | #define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0) |
---|
49 | #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) |
---|
50 | #define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0) |
---|
51 | #define atomic_dec_return(v) atomic_sub_return(1, (v)) |
---|
52 | |
---|
53 | static inline int |
---|
54 | atomic_add_return(int i, atomic_t *v) |
---|
55 | { |
---|
56 | return i + atomic_fetchadd_int(&v->counter, i); |
---|
57 | } |
---|
58 | |
---|
59 | static inline int |
---|
60 | atomic_sub_return(int i, atomic_t *v) |
---|
61 | { |
---|
62 | return atomic_fetchadd_int(&v->counter, -i) - i; |
---|
63 | } |
---|
64 | |
---|
65 | static inline void |
---|
66 | atomic_set(atomic_t *v, int i) |
---|
67 | { |
---|
68 | atomic_store_rel_int(&v->counter, i); |
---|
69 | } |
---|
70 | |
---|
71 | static inline int |
---|
72 | atomic_read(atomic_t *v) |
---|
73 | { |
---|
74 | return atomic_load_acq_int(&v->counter); |
---|
75 | } |
---|
76 | |
---|
77 | static inline int |
---|
78 | atomic_inc(atomic_t *v) |
---|
79 | { |
---|
80 | return atomic_fetchadd_int(&v->counter, 1) + 1; |
---|
81 | } |
---|
82 | |
---|
83 | static inline int |
---|
84 | atomic_dec(atomic_t *v) |
---|
85 | { |
---|
86 | return atomic_fetchadd_int(&v->counter, -1) - 1; |
---|
87 | } |
---|
88 | |
---|
89 | static inline int atomic_add_unless(atomic_t *v, int a, int u) |
---|
90 | { |
---|
91 | int c, old; |
---|
92 | c = atomic_read(v); |
---|
93 | for (;;) { |
---|
94 | if (unlikely(c == (u))) |
---|
95 | break; |
---|
96 | old = atomic_cmpset_int(&v->counter, c, c + (a)); |
---|
97 | if (likely(old == c)) |
---|
98 | break; |
---|
99 | c = old; |
---|
100 | } |
---|
101 | return c != (u); |
---|
102 | } |
---|
103 | |
---|
104 | #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) |
---|
105 | |
---|
106 | |
---|
107 | |
---|
108 | |
---|
109 | #endif /* _ASM_ATOMIC_H_ */ |
---|