xref: /freebsd/lib/libthr/thread/thr_umtx.c (revision 963e8efffe4ab97233102e0e25f95061b6fefbe3)
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 void
34 _thr_umutex_init(struct umutex *mtx)
35 {
36 	static struct umutex default_mtx = DEFAULT_UMUTEX;
37 
38 	*mtx = default_mtx;
39 	mtx->m_spincount = _thr_adaptive_spin;
40 }
41 
42 int
43 __thr_umutex_lock(struct umutex *mtx)
44 {
45 	if (_umtx_op(mtx, UMTX_OP_MUTEX_LOCK, 0, 0, 0) != -1)
46 		return 0;
47 	return (errno);
48 }
49 
50 int
51 __thr_umutex_timedlock(struct umutex *mtx,
52 	const struct timespec *timeout)
53 {
54 	if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
55 		timeout->tv_nsec <= 0)))
56 		return (ETIMEDOUT);
57 	if (_umtx_op(mtx, UMTX_OP_MUTEX_LOCK, 0, 0,
58 		__DECONST(void *, timeout)) != -1)
59 		return (0);
60 	return (errno);
61 }
62 
63 int
64 __thr_umutex_unlock(struct umutex *mtx)
65 {
66 	if (_umtx_op(mtx, UMTX_OP_MUTEX_UNLOCK, 0, 0, 0) != -1)
67 		return (0);
68 	return (errno);
69 }
70 
71 int
72 __thr_umutex_trylock(struct umutex *mtx)
73 {
74 	if (_umtx_op(mtx, UMTX_OP_MUTEX_TRYLOCK, 0, 0, 0) != -1)
75 		return (0);
76 	return (errno);
77 }
78 
79 int
80 __thr_umutex_set_ceiling(struct umutex *mtx, uint32_t ceiling,
81 	uint32_t *oldceiling)
82 {
83 	if (_umtx_op(mtx, UMTX_OP_SET_CEILING, ceiling, oldceiling, 0) != -1)
84 		return (0);
85 	return (errno);
86 }
87 
88 int
89 _thr_umtx_wait(volatile umtx_t *mtx, long id, const struct timespec *timeout)
90 {
91 	if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
92 		timeout->tv_nsec <= 0)))
93 		return (ETIMEDOUT);
94 	if (_umtx_op(__DEVOLATILE(void *, mtx), UMTX_OP_WAIT, id, 0,
95 		__DECONST(void*, timeout)) != -1)
96 		return (0);
97 	return (errno);
98 }
99 
100 int
101 _thr_umtx_wake(volatile umtx_t *mtx, int nr_wakeup)
102 {
103 	if (_umtx_op(__DEVOLATILE(void *, mtx), UMTX_OP_WAKE,
104 		nr_wakeup, 0, 0) != -1)
105 		return (0);
106 	return (errno);
107 }
108 
109 void
110 _thr_ucond_init(struct ucond *cv)
111 {
112 	bzero(cv, sizeof(struct ucond));
113 }
114 
115 int
116 _thr_ucond_wait(struct ucond *cv, struct umutex *m,
117 	const struct timespec *timeout, int check_unparking)
118 {
119 	if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
120 	    timeout->tv_nsec <= 0))) {
121 		__thr_umutex_unlock(m);
122                 return (ETIMEDOUT);
123 	}
124 	if (_umtx_op(cv, UMTX_OP_CV_WAIT,
125 		     check_unparking ? UMTX_CHECK_UNPARKING : 0,
126 		     m, __DECONST(void*, timeout)) != -1) {
127 		return (0);
128 	}
129 	return (errno);
130 }
131 
132 int
133 _thr_ucond_signal(struct ucond *cv)
134 {
135 	if (!cv->c_has_waiters)
136 		return (0);
137 	if (_umtx_op(cv, UMTX_OP_CV_SIGNAL, 0, NULL, NULL) != -1)
138 		return (0);
139 	return (errno);
140 }
141 
142 int
143 _thr_ucond_broadcast(struct ucond *cv)
144 {
145 	if (!cv->c_has_waiters)
146 		return (0);
147 	if (_umtx_op(cv, UMTX_OP_CV_BROADCAST, 0, NULL, NULL) != -1)
148 		return (0);
149 	return (errno);
150 }
151