lock.h revision 1.1 1 1.1 matt /* $NetBSD: lock.h,v 1.1 2014/08/10 05:47:38 matt Exp $ */
2 1.1 matt
3 1.1 matt /*-
4 1.1 matt * Copyright (c) 2014 The NetBSD Foundation, Inc.
5 1.1 matt * All rights reserved.
6 1.1 matt *
7 1.1 matt * This code is derived from software contributed to The NetBSD Foundation
8 1.1 matt * by Matt Thomas of 3am Software Foundry.
9 1.1 matt *
10 1.1 matt * Redistribution and use in source and binary forms, with or without
11 1.1 matt * modification, are permitted provided that the following conditions
12 1.1 matt * are met:
13 1.1 matt * 1. Redistributions of source code must retain the above copyright
14 1.1 matt * notice, this list of conditions and the following disclaimer.
15 1.1 matt * 2. Redistributions in binary form must reproduce the above copyright
16 1.1 matt * notice, this list of conditions and the following disclaimer in the
17 1.1 matt * documentation and/or other materials provided with the distribution.
18 1.1 matt *
19 1.1 matt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 1.1 matt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 1.1 matt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 1.1 matt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 1.1 matt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 1.1 matt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 1.1 matt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 1.1 matt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 1.1 matt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 1.1 matt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 1.1 matt * POSSIBILITY OF SUCH DAMAGE.
30 1.1 matt */
31 1.1 matt /*
32 1.1 matt * Machine-dependent spin lock operations.
33 1.1 matt */
34 1.1 matt
35 1.1 matt #ifndef _AARCH64_LOCK_H_
36 1.1 matt #define _AARCH64_LOCK_H_
37 1.1 matt
38 1.1 matt #ifdef __aarch64__
39 1.1 matt
40 1.1 matt static __inline int
41 1.1 matt __SIMPLELOCK_LOCKED_P(__cpu_simple_lock_t *__ptr)
42 1.1 matt {
43 1.1 matt return *__ptr != __SIMPLELOCK_UNLOCKED;
44 1.1 matt }
45 1.1 matt
46 1.1 matt static __inline int
47 1.1 matt __SIMPLELOCK_UNLOCKED_P(__cpu_simple_lock_t *__ptr)
48 1.1 matt {
49 1.1 matt return *__ptr == __SIMPLELOCK_UNLOCKED;
50 1.1 matt }
51 1.1 matt
52 1.1 matt static __inline void
53 1.1 matt __cpu_simple_lock_clear(__cpu_simple_lock_t *__ptr)
54 1.1 matt {
55 1.1 matt __atomic_clear(__ptr, __ATOMIC_RELAXED);
56 1.1 matt }
57 1.1 matt
58 1.1 matt static __inline void
59 1.1 matt __cpu_simple_lock_set(__cpu_simple_lock_t *__ptr)
60 1.1 matt {
61 1.1 matt (void)__atomic_test_and_set(__ptr, __ATOMIC_RELAXED);
62 1.1 matt }
63 1.1 matt
64 1.1 matt static __inline void __unused
65 1.1 matt __cpu_simple_lock_init(__cpu_simple_lock_t *alp)
66 1.1 matt {
67 1.1 matt __atomic_clear(alp, __ATOMIC_ACQUIRE);
68 1.1 matt }
69 1.1 matt
70 1.1 matt static __inline void __unused
71 1.1 matt __cpu_simple_lock(__cpu_simple_lock_t *alp)
72 1.1 matt {
73 1.1 matt while (__atomic_test_and_set(alp, __ATOMIC_ACQUIRE)) {
74 1.1 matt /* do nothing */
75 1.1 matt }
76 1.1 matt }
77 1.1 matt
78 1.1 matt static __inline int __unused
79 1.1 matt __cpu_simple_lock_try(__cpu_simple_lock_t *alp)
80 1.1 matt {
81 1.1 matt return !__atomic_test_and_set(alp, __ATOMIC_ACQUIRE);
82 1.1 matt }
83 1.1 matt
84 1.1 matt static __inline void __unused
85 1.1 matt __cpu_simple_unlock(__cpu_simple_lock_t *alp)
86 1.1 matt {
87 1.1 matt __atomic_clear(alp, __ATOMIC_RELEASE);
88 1.1 matt }
89 1.1 matt
90 1.1 matt #elif defined(__arm__)
91 1.1 matt
92 1.1 matt #include <arm/lock.h>
93 1.1 matt
94 1.1 matt #endif
95 1.1 matt
96 1.1 matt #endif /* _AARCH64_LOCK_H_ */
97