1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2007 Stephan Uphoff <[email protected]>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the author nor the names of any co-contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * $FreeBSD$
32 */
33
34 #ifndef _SYS_RMLOCK_H_
35 #define _SYS_RMLOCK_H_
36
37 #include <sys/mutex.h>
38 #include <sys/sx.h>
39 #include <sys/_lock.h>
40 #include <sys/_rmlock.h>
41
42 #ifdef _KERNEL
43
44 /*
45 * Flags passed to rm_init_flags(9).
46 */
47 #define RM_NOWITNESS 0x00000001
48 #define RM_RECURSE 0x00000002
49 #define RM_SLEEPABLE 0x00000004
50 #define RM_NEW 0x00000008
51
52 void rm_init(struct rmlock *rm, const char *name);
53 void rm_init_flags(struct rmlock *rm, const char *name, int opts);
54 void rm_destroy(struct rmlock *rm);
55 int rm_wowned(const struct rmlock *rm);
56 void rm_sysinit(void *arg);
57
58 void _rm_wlock_debug(struct rmlock *rm, const char *file, int line);
59 void _rm_wunlock_debug(struct rmlock *rm, const char *file, int line);
60 int _rm_rlock_debug(struct rmlock *rm, struct rm_priotracker *tracker,
61 int trylock, const char *file, int line);
62 void _rm_runlock_debug(struct rmlock *rm, struct rm_priotracker *tracker,
63 const char *file, int line);
64
65 void _rm_wlock(struct rmlock *rm);
66 void _rm_wunlock(struct rmlock *rm);
67 int _rm_rlock(struct rmlock *rm, struct rm_priotracker *tracker,
68 int trylock);
69 void _rm_runlock(struct rmlock *rm, struct rm_priotracker *tracker);
70 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
71 void _rm_assert(const struct rmlock *rm, int what, const char *file,
72 int line);
73 #endif
74
75 /*
76 * Public interface for lock operations.
77 */
78 #ifndef LOCK_DEBUG
79 #error LOCK_DEBUG not defined, include <sys/lock.h> before <sys/rmlock.h>
80 #endif
81
82 #if LOCK_DEBUG > 0
83 #define rm_wlock(rm) _rm_wlock_debug((rm), LOCK_FILE, LOCK_LINE)
84 #define rm_wunlock(rm) _rm_wunlock_debug((rm), LOCK_FILE, LOCK_LINE)
85 #define rm_rlock(rm,tracker) \
86 ((void)_rm_rlock_debug((rm),(tracker), 0, LOCK_FILE, LOCK_LINE ))
87 #define rm_try_rlock(rm,tracker) \
88 _rm_rlock_debug((rm),(tracker), 1, LOCK_FILE, LOCK_LINE )
89 #define rm_runlock(rm,tracker) \
90 _rm_runlock_debug((rm), (tracker), LOCK_FILE, LOCK_LINE )
91 #else
92 #define rm_wlock(rm) _rm_wlock((rm))
93 #define rm_wunlock(rm) _rm_wunlock((rm))
94 #define rm_rlock(rm,tracker) ((void)_rm_rlock((rm),(tracker), 0))
95 #define rm_try_rlock(rm,tracker) _rm_rlock((rm),(tracker), 1)
96 #define rm_runlock(rm,tracker) _rm_runlock((rm), (tracker))
97 #endif
98 #define rm_sleep(chan, rm, pri, wmesg, timo) \
99 _sleep((chan), &(rm)->lock_object, (pri), (wmesg), \
100 tick_sbt * (timo), 0, C_HARDCLOCK)
101
102 struct rm_args {
103 struct rmlock *ra_rm;
104 const char *ra_desc;
105 int ra_flags;
106 };
107
108 #define RM_SYSINIT_FLAGS(name, rm, desc, flags) \
109 static struct rm_args name##_args = { \
110 (rm), \
111 (desc), \
112 (flags), \
113 }; \
114 SYSINIT(name##_rm_sysinit, SI_SUB_LOCK, SI_ORDER_MIDDLE, \
115 rm_sysinit, &name##_args); \
116 SYSUNINIT(name##_rm_sysuninit, SI_SUB_LOCK, SI_ORDER_MIDDLE, \
117 rm_destroy, (rm))
118
119 #define RM_SYSINIT(name, rm, desc) RM_SYSINIT_FLAGS(name, rm, desc, 0)
120
121 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
122 #define RA_LOCKED LA_LOCKED
123 #define RA_RLOCKED LA_SLOCKED
124 #define RA_WLOCKED LA_XLOCKED
125 #define RA_UNLOCKED LA_UNLOCKED
126 #define RA_RECURSED LA_RECURSED
127 #define RA_NOTRECURSED LA_NOTRECURSED
128 #endif
129
130 #ifdef INVARIANTS
131 #define rm_assert(rm, what) _rm_assert((rm), (what), LOCK_FILE, LOCK_LINE)
132 #else
133 #define rm_assert(rm, what)
134 #endif
135
136 void rms_init(struct rmslock *rms, const char *name);
137 void rms_destroy(struct rmslock *rms);
138 void rms_rlock(struct rmslock *rms);
139 int rms_try_rlock(struct rmslock *rms);
140 void rms_runlock(struct rmslock *rms);
141 void rms_wlock(struct rmslock *rms);
142 void rms_wunlock(struct rmslock *rms);
143 void rms_unlock(struct rmslock *rms);
144
145 static inline int
rms_wowned(struct rmslock * rms)146 rms_wowned(struct rmslock *rms)
147 {
148
149 return (rms->owner == curthread);
150 }
151
152 #ifdef INVARIANTS
153 /*
154 * For assertion purposes.
155 *
156 * Main limitation is that we at best can tell there are readers, but not
157 * whether curthread is one of them.
158 */
159 static inline int
rms_rowned(struct rmslock * rms)160 rms_rowned(struct rmslock *rms)
161 {
162
163 return (rms->debug_readers > 0);
164 }
165
166 static inline int
rms_owned_any(struct rmslock * rms)167 rms_owned_any(struct rmslock *rms)
168 {
169
170 if (rms_wowned(rms))
171 return (1);
172
173 return (rms_rowned(rms));
174 }
175 #endif
176
177 #endif /* _KERNEL */
178 #endif /* !_SYS_RMLOCK_H_ */
179