xref: /illumos-gate/usr/src/head/synch.h (revision 6e270ca8)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
24  * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
25  */
26 
27 #ifndef	_SYNCH_H
28 #define	_SYNCH_H
29 
30 /*
31  * synch.h:
32  * definitions needed to use the thread synchronization interface
33  */
34 
35 #ifndef _ASM
36 #include <sys/machlock.h>
37 #include <sys/time_impl.h>
38 #include <sys/synch.h>
39 #endif /* _ASM */
40 
41 #ifdef __cplusplus
42 extern "C" {
43 #endif
44 
45 #ifndef _ASM
46 
47 /*
48  * Semaphores
49  */
50 typedef struct _sema {
51 	/* this structure must be the same as sem_t in <semaphore.h> */
52 	uint32_t	count;		/* semaphore count */
53 	uint16_t	type;
54 	uint16_t	magic;
55 	upad64_t	pad1[3];	/* reserved for a mutex_t */
56 	upad64_t	pad2[2];	/* reserved for a cond_t */
57 } sema_t;
58 
59 /*
60  * POSIX.1c Note:
61  * POSIX.1c requires that <pthread.h> define the structures pthread_mutex_t
62  * and pthread_cond_t.  These structures are identical to mutex_t (lwp_mutex_t)
63  * and cond_t (lwp_cond_t) which are defined in <synch.h>.  A nested included
64  * of <synch.h> (to allow a "#typedef mutex_t  pthread_mutex_t") would pull in
65  * non-posix symbols/constants violating the namespace restrictions.  Hence,
66  * pthread_mutex_t/pthread_cond_t have been redefined in <pthread.h> (actually
67  * in <sys/types.h>).  Any modifications done to mutex_t/lwp_mutex_t or
68  * cond_t/lwp_cond_t should also be done to pthread_mutex_t/pthread_cond_t.
69  */
70 typedef lwp_mutex_t mutex_t;
71 typedef lwp_cond_t cond_t;
72 
73 /*
74  * Readers/writer locks
75  *
76  * NOTE: The layout of this structure should be kept in sync with the layout
77  * of the correponding structure of pthread_rwlock_t in sys/types.h.
78  * Also, there is an identical structure for lwp_rwlock_t in <sys/synch.h>.
79  * Because we have to deal with C++, we cannot redefine this one as that one.
80  */
81 typedef struct _rwlock {
82 	int32_t		readers;	/* rwstate word */
83 	uint16_t	type;
84 	uint16_t	magic;
85 	mutex_t		mutex;		/* used with process-shared rwlocks */
86 	cond_t		readercv;	/* used only to indicate ownership */
87 	cond_t		writercv;	/* used only to indicate ownership */
88 } rwlock_t;
89 
90 int	_lwp_mutex_lock(lwp_mutex_t *);
91 int	_lwp_mutex_unlock(lwp_mutex_t *);
92 int	_lwp_mutex_trylock(lwp_mutex_t *);
93 int	_lwp_cond_wait(lwp_cond_t *, lwp_mutex_t *);
94 int	_lwp_cond_timedwait(lwp_cond_t *, lwp_mutex_t *, timespec_t *);
95 int	_lwp_cond_reltimedwait(lwp_cond_t *, lwp_mutex_t *, timespec_t *);
96 int	_lwp_cond_signal(lwp_cond_t *);
97 int	_lwp_cond_broadcast(lwp_cond_t *);
98 int	_lwp_sema_init(lwp_sema_t *, int);
99 int	_lwp_sema_wait(lwp_sema_t *);
100 int	_lwp_sema_trywait(lwp_sema_t *);
101 int	_lwp_sema_post(lwp_sema_t *);
102 int	cond_init(cond_t *, int, void *);
103 int	cond_destroy(cond_t *);
104 int	cond_wait(cond_t *, mutex_t *);
105 int	cond_timedwait(cond_t *, mutex_t *, const timespec_t *);
106 int	cond_reltimedwait(cond_t *, mutex_t *, const timespec_t *);
107 int	cond_signal(cond_t *);
108 int	cond_broadcast(cond_t *);
109 int	mutex_init(mutex_t *, int, void *);
110 int	mutex_destroy(mutex_t *);
111 int	mutex_consistent(mutex_t *);
112 int	mutex_lock(mutex_t *);
113 int	mutex_trylock(mutex_t *);
114 int	mutex_unlock(mutex_t *);
115 int	rwlock_init(rwlock_t *, int, void *);
116 int	rwlock_destroy(rwlock_t *);
117 int	rw_rdlock(rwlock_t *);
118 int	rw_wrlock(rwlock_t *);
119 int	rw_unlock(rwlock_t *);
120 int	rw_tryrdlock(rwlock_t *);
121 int	rw_trywrlock(rwlock_t *);
122 int	sema_init(sema_t *, unsigned int, int, void *);
123 int	sema_destroy(sema_t *);
124 int	sema_wait(sema_t *);
125 int	sema_timedwait(sema_t *, const timespec_t *);
126 int	sema_reltimedwait(sema_t *, const timespec_t *);
127 int	sema_post(sema_t *);
128 int	sema_trywait(sema_t *);
129 
130 #endif /* _ASM */
131 
132 /* "Magic numbers" tagging synchronization object types */
133 #define	MUTEX_MAGIC	_MUTEX_MAGIC
134 #define	SEMA_MAGIC	_SEMA_MAGIC
135 #define	COND_MAGIC	_COND_MAGIC
136 #define	RWL_MAGIC	_RWL_MAGIC
137 
138 /*
139  * POSIX.1c Note:
140  * DEFAULTMUTEX is defined same as PTHREAD_MUTEX_INITIALIZER in <pthread.h>.
141  * DEFAULTCV is defined same as PTHREAD_COND_INITIALIZER in <pthread.h>.
142  * DEFAULTRWLOCK is defined same as PTHREAD_RWLOCK_INITIALIZER in <pthread.h>.
143  * Any changes to these macros should be reflected in <pthread.h>
144  */
145 #define	DEFAULTMUTEX	\
146 	{{0, 0, 0, {USYNC_THREAD}, MUTEX_MAGIC}, \
147 	{{{0, 0, 0, 0, 0, 0, 0, 0}}}, 0}
148 #define	SHAREDMUTEX	\
149 	{{0, 0, 0, {USYNC_PROCESS}, MUTEX_MAGIC}, \
150 	{{{0, 0, 0, 0, 0, 0, 0, 0}}}, 0}
151 #define	RECURSIVEMUTEX	\
152 	{{0, 0, 0, {USYNC_THREAD|LOCK_RECURSIVE}, MUTEX_MAGIC}, \
153 	{{{0, 0, 0, 0, 0, 0, 0, 0}}}, 0}
154 #define	ERRORCHECKMUTEX	\
155 	{{0, 0, 0, {USYNC_THREAD|LOCK_ERRORCHECK}, MUTEX_MAGIC}, \
156 	{{{0, 0, 0, 0, 0, 0, 0, 0}}}, 0}
157 #define	RECURSIVE_ERRORCHECKMUTEX	\
158 	{{0, 0, 0, {USYNC_THREAD|LOCK_RECURSIVE|LOCK_ERRORCHECK}, \
159 	MUTEX_MAGIC}, {{{0, 0, 0, 0, 0, 0, 0, 0}}}, 0}
160 #define	DEFAULTCV	\
161 	{{{0, 0, 0, 0}, USYNC_THREAD, COND_MAGIC}, 0}
162 #define	SHAREDCV	\
163 	{{{0, 0, 0, 0}, USYNC_PROCESS, COND_MAGIC}, 0}
164 #define	DEFAULTSEMA	\
165 	{0, USYNC_THREAD, SEMA_MAGIC, {0, 0, 0}, {0, 0}}
166 #define	SHAREDSEMA	\
167 	{0, USYNC_PROCESS, SEMA_MAGIC, {0, 0, 0}, {0, 0}}
168 #define	DEFAULTRWLOCK	\
169 	{0, USYNC_THREAD, RWL_MAGIC, DEFAULTMUTEX, DEFAULTCV, DEFAULTCV}
170 #define	SHAREDRWLOCK	\
171 	{0, USYNC_PROCESS, RWL_MAGIC, SHAREDMUTEX, SHAREDCV, SHAREDCV}
172 
173 /*
174  * Tests on lock states.
175  */
176 #define	SEMA_HELD(x)		_sema_held(x)
177 #define	RW_READ_HELD(x)		_rw_read_held(x)
178 #define	RW_WRITE_HELD(x)	_rw_write_held(x)
179 #define	RW_LOCK_HELD(x)		(RW_READ_HELD(x) || RW_WRITE_HELD(x))
180 #define	MUTEX_HELD(x)		_mutex_held(x)
181 
182 /*
183  * The following definitions are for assertions which can be checked
184  * statically by tools like lock_lint.  You can also define your own
185  * run-time test for each.  If you don't, we define them to 1 so that
186  * such assertions simply pass.
187  */
188 #ifndef NO_LOCKS_HELD
189 #define	NO_LOCKS_HELD	1
190 #endif
191 #ifndef NO_COMPETING_THREADS
192 #define	NO_COMPETING_THREADS	1
193 #endif
194 
195 #ifndef _ASM
196 
197 /*
198  * The *_held() functions apply equally well to Solaris threads
199  * and to Posix threads synchronization objects, but the formal
200  * type declarations are different, so we just declare the argument
201  * to each *_held() function to be a void *, expecting that they will
202  * be called with the proper type of argument in each case.
203  */
204 int _sema_held(void *);			/* sema_t or sem_t */
205 int _rw_read_held(void *);		/* rwlock_t or pthread_rwlock_t */
206 int _rw_write_held(void *);		/* rwlock_t or pthread_rwlock_t */
207 int _mutex_held(void *);		/* mutex_t or pthread_mutex_t */
208 
209 /* Pause API */
210 void smt_pause(void);
211 
212 #endif /* _ASM */
213 
214 /*
215  * Panicking versions of our favorite friends.
216  */
217 void mutex_enter(mutex_t *);
218 void mutex_exit(mutex_t *);
219 
220 #ifdef	__cplusplus
221 }
222 #endif
223 
224 #endif	/* _SYNCH_H */
225