1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2005 David Xu <davidxu@freebsd.org>
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 unmodified, this list of conditions, and the following
12 * disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include "thr_private.h"
30 #include "thr_umtx.h"
31
32 #ifndef HAS__UMTX_OP_ERR
_umtx_op_err(void * obj,int op,u_long val,void * uaddr,void * uaddr2)33 int _umtx_op_err(void *obj, int op, u_long val, void *uaddr, void *uaddr2)
34 {
35
36 if (_umtx_op(obj, op, val, uaddr, uaddr2) == -1)
37 return (errno);
38 return (0);
39 }
40 #endif
41
42 void
_thr_umutex_init(struct umutex * mtx)43 _thr_umutex_init(struct umutex *mtx)
44 {
45 static const struct umutex default_mtx = DEFAULT_UMUTEX;
46
47 *mtx = default_mtx;
48 }
49
50 void
_thr_urwlock_init(struct urwlock * rwl)51 _thr_urwlock_init(struct urwlock *rwl)
52 {
53 static const struct urwlock default_rwl = DEFAULT_URWLOCK;
54
55 *rwl = default_rwl;
56 }
57
58 int
__thr_umutex_lock(struct umutex * mtx,uint32_t id)59 __thr_umutex_lock(struct umutex *mtx, uint32_t id)
60 {
61 uint32_t owner;
62
63 if ((mtx->m_flags & (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT)) != 0)
64 return (_umtx_op_err(mtx, UMTX_OP_MUTEX_LOCK, 0, 0, 0));
65
66 for (;;) {
67 owner = mtx->m_owner;
68 if ((owner & ~UMUTEX_CONTESTED) == 0 &&
69 atomic_cmpset_acq_32(&mtx->m_owner, owner, id | owner))
70 return (0);
71 if (owner == UMUTEX_RB_OWNERDEAD &&
72 atomic_cmpset_acq_32(&mtx->m_owner, owner,
73 id | UMUTEX_CONTESTED))
74 return (EOWNERDEAD);
75 if (owner == UMUTEX_RB_NOTRECOV)
76 return (ENOTRECOVERABLE);
77
78 /* wait in kernel */
79 _umtx_op_err(mtx, UMTX_OP_MUTEX_WAIT, 0, 0, 0);
80 }
81 }
82
83 #define SPINLOOPS 1000
84
85 int
__thr_umutex_lock_spin(struct umutex * mtx,uint32_t id)86 __thr_umutex_lock_spin(struct umutex *mtx, uint32_t id)
87 {
88 uint32_t owner;
89 int count;
90
91 if (!_thr_is_smp)
92 return (__thr_umutex_lock(mtx, id));
93 if ((mtx->m_flags & (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT)) != 0)
94 return (_umtx_op_err(mtx, UMTX_OP_MUTEX_LOCK, 0, 0, 0));
95
96 for (;;) {
97 count = SPINLOOPS;
98 while (count--) {
99 owner = mtx->m_owner;
100 if ((owner & ~UMUTEX_CONTESTED) == 0 &&
101 atomic_cmpset_acq_32(&mtx->m_owner, owner,
102 id | owner))
103 return (0);
104 if (__predict_false(owner == UMUTEX_RB_OWNERDEAD) &&
105 atomic_cmpset_acq_32(&mtx->m_owner, owner,
106 id | UMUTEX_CONTESTED))
107 return (EOWNERDEAD);
108 if (__predict_false(owner == UMUTEX_RB_NOTRECOV))
109 return (ENOTRECOVERABLE);
110 CPU_SPINWAIT;
111 }
112
113 /* wait in kernel */
114 _umtx_op_err(mtx, UMTX_OP_MUTEX_WAIT, 0, 0, 0);
115 }
116 }
117
118 int
__thr_umutex_timedlock(struct umutex * mtx,uint32_t id,const struct timespec * abstime)119 __thr_umutex_timedlock(struct umutex *mtx, uint32_t id,
120 const struct timespec *abstime)
121 {
122 struct _umtx_time *tm_p, timeout;
123 size_t tm_size;
124 uint32_t owner;
125 int ret;
126
127 if (abstime == NULL) {
128 tm_p = NULL;
129 tm_size = 0;
130 } else {
131 timeout._clockid = CLOCK_REALTIME;
132 timeout._flags = UMTX_ABSTIME;
133 timeout._timeout = *abstime;
134 tm_p = &timeout;
135 tm_size = sizeof(timeout);
136 }
137
138 for (;;) {
139 if ((mtx->m_flags & (UMUTEX_PRIO_PROTECT |
140 UMUTEX_PRIO_INHERIT)) == 0) {
141 /* try to lock it */
142 owner = mtx->m_owner;
143 if ((owner & ~UMUTEX_CONTESTED) == 0 &&
144 atomic_cmpset_acq_32(&mtx->m_owner, owner,
145 id | owner))
146 return (0);
147 if (__predict_false(owner == UMUTEX_RB_OWNERDEAD) &&
148 atomic_cmpset_acq_32(&mtx->m_owner, owner,
149 id | UMUTEX_CONTESTED))
150 return (EOWNERDEAD);
151 if (__predict_false(owner == UMUTEX_RB_NOTRECOV))
152 return (ENOTRECOVERABLE);
153 /* wait in kernel */
154 ret = _umtx_op_err(mtx, UMTX_OP_MUTEX_WAIT, 0,
155 (void *)tm_size, __DECONST(void *, tm_p));
156 } else {
157 ret = _umtx_op_err(mtx, UMTX_OP_MUTEX_LOCK, 0,
158 (void *)tm_size, __DECONST(void *, tm_p));
159 if (ret == 0 || ret == EOWNERDEAD ||
160 ret == ENOTRECOVERABLE)
161 break;
162 }
163 if (ret == ETIMEDOUT)
164 break;
165 }
166 return (ret);
167 }
168
169 int
__thr_umutex_unlock(struct umutex * mtx)170 __thr_umutex_unlock(struct umutex *mtx)
171 {
172
173 return (_umtx_op_err(mtx, UMTX_OP_MUTEX_UNLOCK, 0, 0, 0));
174 }
175
176 int
__thr_umutex_trylock(struct umutex * mtx)177 __thr_umutex_trylock(struct umutex *mtx)
178 {
179
180 return (_umtx_op_err(mtx, UMTX_OP_MUTEX_TRYLOCK, 0, 0, 0));
181 }
182
183 int
__thr_umutex_set_ceiling(struct umutex * mtx,uint32_t ceiling,uint32_t * oldceiling)184 __thr_umutex_set_ceiling(struct umutex *mtx, uint32_t ceiling,
185 uint32_t *oldceiling)
186 {
187
188 return (_umtx_op_err(mtx, UMTX_OP_SET_CEILING, ceiling, oldceiling, 0));
189 }
190
191 int
_thr_umtx_wait(volatile long * mtx,long id,const struct timespec * timeout)192 _thr_umtx_wait(volatile long *mtx, long id, const struct timespec *timeout)
193 {
194
195 if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
196 timeout->tv_nsec <= 0)))
197 return (ETIMEDOUT);
198 return (_umtx_op_err(__DEVOLATILE(void *, mtx), UMTX_OP_WAIT, id, 0,
199 __DECONST(void*, timeout)));
200 }
201
202 int
_thr_umtx_wait_uint(volatile u_int * mtx,u_int id,const struct timespec * timeout,int shared)203 _thr_umtx_wait_uint(volatile u_int *mtx, u_int id,
204 const struct timespec *timeout, int shared)
205 {
206
207 if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
208 timeout->tv_nsec <= 0)))
209 return (ETIMEDOUT);
210 return (_umtx_op_err(__DEVOLATILE(void *, mtx), shared ?
211 UMTX_OP_WAIT_UINT : UMTX_OP_WAIT_UINT_PRIVATE, id, 0,
212 __DECONST(void*, timeout)));
213 }
214
215 int
_thr_umtx_timedwait_uint(volatile u_int * mtx,u_int id,int clockid,const struct timespec * abstime,int shared)216 _thr_umtx_timedwait_uint(volatile u_int *mtx, u_int id, int clockid,
217 const struct timespec *abstime, int shared)
218 {
219 struct _umtx_time *tm_p, timeout;
220 size_t tm_size;
221
222 if (abstime == NULL) {
223 tm_p = NULL;
224 tm_size = 0;
225 } else {
226 timeout._clockid = clockid;
227 timeout._flags = UMTX_ABSTIME;
228 timeout._timeout = *abstime;
229 tm_p = &timeout;
230 tm_size = sizeof(timeout);
231 }
232
233 return (_umtx_op_err(__DEVOLATILE(void *, mtx), shared ?
234 UMTX_OP_WAIT_UINT : UMTX_OP_WAIT_UINT_PRIVATE, id,
235 (void *)tm_size, __DECONST(void *, tm_p)));
236 }
237
238 int
_thr_umtx_wake(volatile void * mtx,int nr_wakeup,int shared)239 _thr_umtx_wake(volatile void *mtx, int nr_wakeup, int shared)
240 {
241
242 return (_umtx_op_err(__DEVOLATILE(void *, mtx), shared ?
243 UMTX_OP_WAKE : UMTX_OP_WAKE_PRIVATE, nr_wakeup, 0, 0));
244 }
245
246 void
_thr_ucond_init(struct ucond * cv)247 _thr_ucond_init(struct ucond *cv)
248 {
249
250 bzero(cv, sizeof(struct ucond));
251 }
252
253 int
_thr_ucond_wait(struct ucond * cv,struct umutex * m,const struct timespec * timeout,int flags)254 _thr_ucond_wait(struct ucond *cv, struct umutex *m,
255 const struct timespec *timeout, int flags)
256 {
257 struct pthread *curthread;
258
259 if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
260 timeout->tv_nsec <= 0))) {
261 curthread = _get_curthread();
262 _thr_umutex_unlock(m, TID(curthread));
263 return (ETIMEDOUT);
264 }
265 return (_umtx_op_err(cv, UMTX_OP_CV_WAIT, flags, m,
266 __DECONST(void*, timeout)));
267 }
268
269 int
_thr_ucond_signal(struct ucond * cv)270 _thr_ucond_signal(struct ucond *cv)
271 {
272
273 if (!cv->c_has_waiters)
274 return (0);
275 return (_umtx_op_err(cv, UMTX_OP_CV_SIGNAL, 0, NULL, NULL));
276 }
277
278 int
_thr_ucond_broadcast(struct ucond * cv)279 _thr_ucond_broadcast(struct ucond *cv)
280 {
281
282 if (!cv->c_has_waiters)
283 return (0);
284 return (_umtx_op_err(cv, UMTX_OP_CV_BROADCAST, 0, NULL, NULL));
285 }
286
287 int
__thr_rwlock_rdlock(struct urwlock * rwlock,int flags,const struct timespec * tsp)288 __thr_rwlock_rdlock(struct urwlock *rwlock, int flags,
289 const struct timespec *tsp)
290 {
291 struct _umtx_time timeout, *tm_p;
292 size_t tm_size;
293
294 if (tsp == NULL) {
295 tm_p = NULL;
296 tm_size = 0;
297 } else {
298 timeout._timeout = *tsp;
299 timeout._flags = UMTX_ABSTIME;
300 timeout._clockid = CLOCK_REALTIME;
301 tm_p = &timeout;
302 tm_size = sizeof(timeout);
303 }
304 return (_umtx_op_err(rwlock, UMTX_OP_RW_RDLOCK, flags,
305 (void *)tm_size, tm_p));
306 }
307
308 int
__thr_rwlock_wrlock(struct urwlock * rwlock,const struct timespec * tsp)309 __thr_rwlock_wrlock(struct urwlock *rwlock, const struct timespec *tsp)
310 {
311 struct _umtx_time timeout, *tm_p;
312 size_t tm_size;
313
314 if (tsp == NULL) {
315 tm_p = NULL;
316 tm_size = 0;
317 } else {
318 timeout._timeout = *tsp;
319 timeout._flags = UMTX_ABSTIME;
320 timeout._clockid = CLOCK_REALTIME;
321 tm_p = &timeout;
322 tm_size = sizeof(timeout);
323 }
324 return (_umtx_op_err(rwlock, UMTX_OP_RW_WRLOCK, 0, (void *)tm_size,
325 tm_p));
326 }
327
328 int
__thr_rwlock_unlock(struct urwlock * rwlock)329 __thr_rwlock_unlock(struct urwlock *rwlock)
330 {
331
332 return (_umtx_op_err(rwlock, UMTX_OP_RW_UNLOCK, 0, NULL, NULL));
333 }
334
335 void
_thr_rwl_rdlock(struct urwlock * rwlock)336 _thr_rwl_rdlock(struct urwlock *rwlock)
337 {
338 int ret;
339
340 for (;;) {
341 if (_thr_rwlock_tryrdlock(rwlock, URWLOCK_PREFER_READER) == 0)
342 return;
343 ret = __thr_rwlock_rdlock(rwlock, URWLOCK_PREFER_READER, NULL);
344 if (ret == 0)
345 return;
346 if (ret != EINTR)
347 PANIC("rdlock error");
348 }
349 }
350
351 void
_thr_rwl_wrlock(struct urwlock * rwlock)352 _thr_rwl_wrlock(struct urwlock *rwlock)
353 {
354 int ret;
355
356 for (;;) {
357 if (_thr_rwlock_trywrlock(rwlock) == 0)
358 return;
359 ret = __thr_rwlock_wrlock(rwlock, NULL);
360 if (ret == 0)
361 return;
362 if (ret != EINTR)
363 PANIC("wrlock error");
364 }
365 }
366
367 void
_thr_rwl_unlock(struct urwlock * rwlock)368 _thr_rwl_unlock(struct urwlock *rwlock)
369 {
370
371 if (_thr_rwlock_unlock(rwlock))
372 PANIC("unlock error");
373 }
374