xref: /freebsd/lib/libthr/thread/thr_umtx.h (revision 87569f75a91f298c52a71823c04d41cf53c88889)
1 /*-
2  * Copyright (c) 2005 David Xu <davidxu@freebsd.org>
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, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef _THR_FBSD_UMTX_H_
30 #define _THR_FBSD_UMTX_H_
31 
32 #include <sys/umtx.h>
33 
34 typedef long umtx_t;
35 
36 int __thr_umtx_lock(volatile umtx_t *mtx, long id) __hidden;
37 int __thr_umtx_timedlock(volatile umtx_t *mtx, long id,
38 	const struct timespec *timeout) __hidden;
39 int __thr_umtx_unlock(volatile umtx_t *mtx, long id) __hidden;
40 
41 static inline void
42 _thr_umtx_init(volatile umtx_t *mtx)
43 {
44     *mtx = 0;
45 }
46 
47 static inline int
48 _thr_umtx_trylock(volatile umtx_t *mtx, long id)
49 {
50     if (atomic_cmpset_acq_ptr((volatile uintptr_t *)mtx,
51 	(uintptr_t)UMTX_UNOWNED, (uintptr_t)id))
52 	return (0);
53     return (EBUSY);
54 }
55 
56 static inline int
57 _thr_umtx_lock(volatile umtx_t *mtx, long id)
58 {
59     if (atomic_cmpset_acq_ptr((volatile uintptr_t *)mtx,
60 	(uintptr_t)UMTX_UNOWNED, (uintptr_t)id))
61 	return (0);
62     return (__thr_umtx_lock(mtx, id));
63 }
64 
65 static inline int
66 _thr_umtx_timedlock(volatile umtx_t *mtx, long id,
67 	const struct timespec *timeout)
68 {
69     if (atomic_cmpset_acq_ptr((volatile uintptr_t *)mtx,
70 	(uintptr_t)UMTX_UNOWNED, (uintptr_t)id))
71 	return (0);
72     return (__thr_umtx_timedlock(mtx, id, timeout));
73 }
74 
75 static inline int
76 _thr_umtx_unlock(volatile umtx_t *mtx, long id)
77 {
78     if (atomic_cmpset_rel_ptr((volatile uintptr_t *)mtx,
79 	(uintptr_t)id, (uintptr_t)UMTX_UNOWNED))
80 	return (0);
81     return __thr_umtx_unlock(mtx, id);
82 }
83 
84 int _thr_umtx_wait(volatile umtx_t *mtx, umtx_t exp,
85 	const struct timespec *timeout) __hidden;
86 int _thr_umtx_wake(volatile umtx_t *mtx, int count) __hidden;
87 #endif
88