1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
/**
* @file
*
* @ingroup rtems_bsd_rtems
*
* @brief TODO.
*/
/*
* Copyright (c) 2011 OPTI Medical. All rights reserved.
*
* OPTI Medical
* 235 Hembree Park Drive
* Roswell, GA 30076
* USA
* <kevin.kirspel@optimedical.com>
*
* Copyright (c) 2013-2015 embedded brains GmbH. All rights reserved.
*
* embedded brains GmbH
* Dornierstr. 4
* 82178 Puchheim
* Germany
* <rtems@embedded-brains.de>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <machine/rtems-bsd-kernel-space.h>
#include <machine/rtems-bsd-muteximpl.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#ifndef INVARIANTS
#define _rw_assert(rw, what, file, line)
#endif
static void assert_rw(const struct lock_object *lock, int what);
static void lock_rw(struct lock_object *lock, uintptr_t how);
static uintptr_t unlock_rw(struct lock_object *lock);
struct lock_class lock_class_rw = {
.lc_name = "rw",
.lc_flags = LC_SLEEPLOCK | LC_RECURSABLE | LC_UPGRADABLE,
.lc_assert = assert_rw,
.lc_lock = lock_rw,
.lc_unlock = unlock_rw,
};
#define rw_wowner(rw) rtems_bsd_mutex_owner(&(rw)->mutex)
#define rw_recursed(rw) rtems_bsd_mutex_recursed(&(rw)->mutex)
void
assert_rw(const struct lock_object *lock, int what)
{
rw_assert((const struct rwlock *)lock, what);
}
void
lock_rw(struct lock_object *lock, uintptr_t how)
{
rw_wlock((struct rwlock *)lock);
}
uintptr_t
unlock_rw(struct lock_object *lock)
{
rw_unlock((struct rwlock *)lock);
return (0);
}
void
rw_init_flags(struct rwlock *rw, const char *name, int opts)
{
int flags;
flags = LO_UPGRADABLE;
if (opts & RW_RECURSE)
flags |= LO_RECURSABLE;
rtems_bsd_mutex_init(&rw->lock_object, &rw->mutex, &lock_class_rw,
name, NULL, flags);
}
void
rw_destroy(struct rwlock *rw)
{
rtems_bsd_mutex_destroy(&rw->lock_object, &rw->mutex);
}
void
rw_sysinit(void *arg)
{
struct rw_args *args;
args = arg;
rw_init(args->ra_rw, args->ra_desc);
}
int
rw_wowned(struct rwlock *rw)
{
return (rtems_bsd_mutex_owned(&rw->mutex));
}
void
_rw_wlock(struct rwlock *rw, const char *file, int line)
{
rtems_bsd_mutex_lock(&rw->lock_object, &rw->mutex);
}
int
_rw_try_wlock(struct rwlock *rw, const char *file, int line)
{
return (rtems_bsd_mutex_trylock(&rw->lock_object, &rw->mutex));
}
void
_rw_wunlock(struct rwlock *rw, const char *file, int line)
{
rtems_bsd_mutex_unlock(&rw->mutex);
}
void
_rw_rlock(struct rwlock *rw, const char *file, int line)
{
rtems_bsd_mutex_lock(&rw->lock_object, &rw->mutex);
}
int
_rw_try_rlock(struct rwlock *rw, const char *file, int line)
{
return (rtems_bsd_mutex_trylock(&rw->lock_object, &rw->mutex));
}
void
_rw_runlock(struct rwlock *rw, const char *file, int line)
{
rtems_bsd_mutex_unlock(&rw->mutex);
}
int
_rw_try_upgrade(struct rwlock *rw, const char *file, int line)
{
return (1);
}
void
_rw_downgrade(struct rwlock *rw, const char *file, int line)
{
/* Nothing to do */
}
#ifdef INVARIANT_SUPPORT
/*
* In the non-WITNESS case, rw_assert() can only detect that at least
* *some* thread owns an rlock, but it cannot guarantee that *this*
* thread owns an rlock.
*/
void
_rw_assert(const struct rwlock *rw, int what, const char *file, int line)
{
const char *name = rtems_bsd_mutex_name(&rw->mutex);
switch (what) {
case RA_LOCKED:
case RA_LOCKED | RA_RECURSED:
case RA_LOCKED | RA_NOTRECURSED:
case RA_RLOCKED:
case RA_RLOCKED | RA_RECURSED:
case RA_RLOCKED | RA_NOTRECURSED:
case RA_WLOCKED:
case RA_WLOCKED | RA_RECURSED:
case RA_WLOCKED | RA_NOTRECURSED:
if (rw_wowner(rw) != _Thread_Get_executing())
panic("Lock %s not exclusively locked @ %s:%d\n",
name, file, line);
if (rw_recursed(rw)) {
if (what & RA_NOTRECURSED)
panic("Lock %s recursed @ %s:%d\n", name, file,
line);
} else if (what & RA_RECURSED)
panic("Lock %s not recursed @ %s:%d\n", name, file,
line);
break;
case RA_UNLOCKED:
#ifdef WITNESS
witness_assert(&rw->lock_object, what, file, line);
#else
/*
* If we hold a write lock fail. We can't reliably check
* to see if we hold a read lock or not.
*/
if (rw_wowner(rw) == _Thread_Get_executing())
panic("Lock %s exclusively locked @ %s:%d\n", name,
file, line);
#endif
break;
default:
panic("Unknown rw lock assertion: %d @ %s:%d", what, file,
line);
}
}
#endif /* INVARIANT_SUPPORT */
|
