1 /*
2 * Copyright (c) 2016 Mellanox Technologies, Ltd.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice unmodified, this list of conditions, and the following
10 * disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #ifndef _ASM_ATOMIC_LONG_H_
28 #define _ASM_ATOMIC_LONG_H_
29
30 typedef struct {
31 volatile long counter;
32 } atomic_long_t;
33
34 static inline void
atomic_long_set(atomic_long_t * v,long i)35 atomic_long_set(atomic_long_t *v, long i)
36 {
37 WRITE_ONCE(v->counter, i);
38 }
39
40 static inline long
atomic_long_xchg(atomic_long_t * v,long val)41 atomic_long_xchg(atomic_long_t *v, long val)
42 {
43 return atomic_swap_long(&v->counter, val);
44 }
45
46 static inline long
atomic_long_cmpxchg(atomic_long_t * v,long old,long new)47 atomic_long_cmpxchg(atomic_long_t *v, long old, long new)
48 {
49 long ret = old;
50
51 for (;;) {
52 if (atomic_fcmpset_long(&v->counter, &ret, new))
53 break;
54 if (ret != old)
55 break;
56 }
57 return (ret);
58 }
59
60 static inline int
atomic_long_add_unless(atomic64_t * v,long a,long u)61 atomic_long_add_unless(atomic64_t *v, long a, long u)
62 {
63 long c = atomic64_read(v);
64
65 for (;;) {
66 if (unlikely(c == u))
67 break;
68 if (likely(atomic_fcmpset_long(&v->counter, &c, c + a)))
69 break;
70 }
71 return (c != u);
72 }
73
74 #define atomic_long_inc_not_zero(v) atomic_long_add_unless((v), 1, 0)
75
76 #endif /* _ASM_ATOMIC_LONG_H_ */
77