xref: /freebsd/sys/sys/rmlock.h (revision 9a14aa017b21c292740c00ee098195cd46642730)
1 /*-
2  * Copyright (c) 2007 Stephan Uphoff <ups@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  * 3. Neither the name of the author nor the names of any co-contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #ifndef _SYS_RMLOCK_H_
33 #define _SYS_RMLOCK_H_
34 
35 #include <sys/mutex.h>
36 #include <sys/sx.h>
37 #include <sys/_lock.h>
38 #include <sys/_rmlock.h>
39 
40 #ifdef _KERNEL
41 
42 /*
43  * Flags passed to rm_init(9).
44  */
45 #define	RM_NOWITNESS	0x00000001
46 #define	RM_RECURSE	0x00000002
47 #define	RM_SLEEPABLE	0x00000004
48 
49 void	rm_init(struct rmlock *rm, const char *name);
50 void	rm_init_flags(struct rmlock *rm, const char *name, int opts);
51 void	rm_destroy(struct rmlock *rm);
52 int	rm_wowned(const struct rmlock *rm);
53 void	rm_sysinit(void *arg);
54 void	rm_sysinit_flags(void *arg);
55 
56 void	_rm_wlock_debug(struct rmlock *rm, const char *file, int line);
57 void	_rm_wunlock_debug(struct rmlock *rm, const char *file, int line);
58 int	_rm_rlock_debug(struct rmlock *rm, struct rm_priotracker *tracker,
59 	    int trylock, const char *file, int line);
60 void	_rm_runlock_debug(struct rmlock *rm,  struct rm_priotracker *tracker,
61 	    const char *file, int line);
62 
63 void	_rm_wlock(struct rmlock *rm);
64 void	_rm_wunlock(struct rmlock *rm);
65 int	_rm_rlock(struct rmlock *rm, struct rm_priotracker *tracker,
66 	    int trylock);
67 void	_rm_runlock(struct rmlock *rm,  struct rm_priotracker *tracker);
68 
69 /*
70  * Public interface for lock operations.
71  */
72 #ifndef LOCK_DEBUG
73 #error LOCK_DEBUG not defined, include <sys/lock.h> before <sys/rmlock.h>
74 #endif
75 
76 #if LOCK_DEBUG > 0
77 #define	rm_wlock(rm)	_rm_wlock_debug((rm), LOCK_FILE, LOCK_LINE)
78 #define	rm_wunlock(rm)	_rm_wunlock_debug((rm), LOCK_FILE, LOCK_LINE)
79 #define	rm_rlock(rm,tracker)  \
80     ((void)_rm_rlock_debug((rm),(tracker), 0, LOCK_FILE, LOCK_LINE ))
81 #define	rm_try_rlock(rm,tracker)  \
82     _rm_rlock_debug((rm),(tracker), 1, LOCK_FILE, LOCK_LINE )
83 #define	rm_runlock(rm,tracker)	\
84     _rm_runlock_debug((rm), (tracker), LOCK_FILE, LOCK_LINE )
85 #else
86 #define	rm_wlock(rm)			_rm_wlock((rm))
87 #define	rm_wunlock(rm)			_rm_wunlock((rm))
88 #define	rm_rlock(rm,tracker)		((void)_rm_rlock((rm),(tracker), 0))
89 #define	rm_try_rlock(rm,tracker)	_rm_rlock((rm),(tracker), 1)
90 #define	rm_runlock(rm,tracker)		_rm_runlock((rm), (tracker))
91 #endif
92 
93 struct rm_args {
94 	struct rmlock	*ra_rm;
95 	const char 	*ra_desc;
96 };
97 
98 struct rm_args_flags {
99 	struct rmlock	*ra_rm;
100 	const char 	*ra_desc;
101 	int		ra_opts;
102 };
103 
104 #define	RM_SYSINIT(name, rm, desc)       				\
105 	static struct rm_args name##_args = {				\
106 		(rm),							\
107 		(desc),							\
108 	};								\
109 	SYSINIT(name##_rm_sysinit, SI_SUB_LOCK, SI_ORDER_MIDDLE,	\
110 	    rm_sysinit, &name##_args);					\
111 	SYSUNINIT(name##_rm_sysuninit, SI_SUB_LOCK, SI_ORDER_MIDDLE,	\
112 	    rm_destroy, (rm))
113 
114 
115 #define	RM_SYSINIT_FLAGS(name, rm, desc, opts)       			\
116 	static struct rm_args name##_args = {				\
117 		(rm),							\
118 		(desc),							\
119                 (opts),							\
120 	};								\
121 	SYSINIT(name##_rm_sysinit, SI_SUB_LOCK, SI_ORDER_MIDDLE,	\
122 	    rm_sysinit_flags, &name##_args);				\
123 	SYSUNINIT(name##_rm_sysuninit, SI_SUB_LOCK, SI_ORDER_MIDDLE,	\
124 	    rm_destroy, (rm))
125 
126 #endif /* _KERNEL */
127 #endif /* !_SYS_RMLOCK_H_ */
128