1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright 2018 Nexenta Systems, Inc. All rights reserved.
14 * Copyright 2017 RackTop Systems.
15 */
16
17 /*
18 * mutex(9f)
19 */
20
21 /* This is the API we're emulating */
22 #include <sys/mutex.h>
23
24 #include <sys/errno.h>
25 #include <sys/debug.h>
26 #include <sys/thread.h>
27
28 int _lwp_mutex_lock(lwp_mutex_t *);
29 int _lwp_mutex_unlock(lwp_mutex_t *);
30 int _lwp_mutex_trylock(lwp_mutex_t *);
31
32 extern clock_t ddi_get_lbolt(void);
33
34 /* See: head/synch.h ERRORCHECKMUTEX */
35 static const lwp_mutex_t default_mutex =
36 {{0, 0, 0, {USYNC_THREAD|LOCK_ERRORCHECK}, _MUTEX_MAGIC},
37 {{{0, 0, 0, 0, 0, 0, 0, 0}}}, 0};
38
39 /* ARGSUSED */
40 void
kmutex_init(kmutex_t * mp,char * name,kmutex_type_t typ,void * arg)41 kmutex_init(kmutex_t *mp, char *name, kmutex_type_t typ, void *arg)
42 {
43 mp->m_lock = default_mutex;
44 mp->m_owner = _KTHREAD_INVALID;
45 }
46
47 /* ARGSUSED */
48 void
kmutex_destroy(kmutex_t * mp)49 kmutex_destroy(kmutex_t *mp)
50 {
51 mp->m_owner = _KTHREAD_INVALID;
52 }
53
54 void
kmutex_enter(kmutex_t * mp)55 kmutex_enter(kmutex_t *mp)
56 {
57 kthread_t *t = _curthread();
58
59 VERIFY(mp->m_owner != t);
60 VERIFY(0 == _lwp_mutex_lock(&mp->m_lock));
61 mp->m_owner = t;
62 }
63
64 int
mutex_tryenter(kmutex_t * mp)65 mutex_tryenter(kmutex_t *mp)
66 {
67 int rc;
68
69 rc = _lwp_mutex_trylock(&mp->m_lock);
70 if (rc == 0) {
71 mp->m_owner = _curthread();
72 return (1);
73 }
74 return (0);
75 }
76
77 void
kmutex_exit(kmutex_t * mp)78 kmutex_exit(kmutex_t *mp)
79 {
80 ASSERT(mp->m_owner == _curthread());
81 mp->m_owner = _KTHREAD_INVALID;
82 (void) _lwp_mutex_unlock(&mp->m_lock);
83 }
84
85 /*
86 * Returns the kthread_t * of the owner.
87 */
88 void *
mutex_owner(const kmutex_t * mp)89 mutex_owner(const kmutex_t *mp)
90 {
91 return (mp->m_owner);
92 }
93
94 int
mutex_owned(const kmutex_t * mp)95 mutex_owned(const kmutex_t *mp)
96 {
97 void *t = _curthread();
98 return (t == mp->m_owner);
99 }
100