xref: /freebsd/lib/libthr/thread/thr_umtx.c (revision c0b9f4fe659b6839541970eb5675e57f4d814969)
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 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  * $FreeBSD$
27  *
28  */
29 
30 #include "thr_private.h"
31 #include "thr_umtx.h"
32 
33 int
34 __thr_umtx_lock(volatile umtx_t *mtx, long id)
35 {
36 	while (_umtx_op((struct umtx *)mtx, UMTX_OP_LOCK, id, 0, 0))
37 		;
38 	return (0);
39 }
40 
41 int
42 __thr_umtx_timedlock(volatile umtx_t *mtx, long id,
43 	const struct timespec *timeout)
44 {
45 	if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
46 		timeout->tv_nsec <= 0)))
47 		return (ETIMEDOUT);
48 	if (_umtx_op((struct umtx *)mtx, UMTX_OP_LOCK, id, 0,
49 		(void *)timeout) == 0)
50 		return (0);
51 	return (errno);
52 }
53 
54 int
55 __thr_umtx_unlock(volatile umtx_t *mtx, long id)
56 {
57 	if (_umtx_op((struct umtx *)mtx, UMTX_OP_UNLOCK, id, 0, 0) == 0)
58 		return (0);
59 	return (errno);
60 }
61 
62 int
63 _thr_umtx_wait(volatile umtx_t *mtx, long id, const struct timespec *timeout)
64 {
65 	if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
66 		timeout->tv_nsec <= 0)))
67 		return (ETIMEDOUT);
68 	if (_umtx_op((struct umtx *)mtx, UMTX_OP_WAIT, id, 0,
69 		(void*) timeout) == 0)
70 		return (0);
71 	return (errno);
72 }
73 
74 int
75 _thr_umtx_wake(volatile umtx_t *mtx, int nr_wakeup)
76 {
77 	if (_umtx_op((struct umtx *)mtx, UMTX_OP_WAKE, nr_wakeup, 0, 0) == 0)
78 		return (0);
79 	return (errno);
80 }
81