xref: /netbsd-src/lib/librumpuser/rumpuser_pth.c (revision a4ddc2c8fb9af816efe3b1c375a5530aef0e89e9)
1 /*	$NetBSD: rumpuser_pth.c,v 1.12 2013/02/11 16:02:31 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2007-2010 Antti Kantee.  All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include "rumpuser_port.h"
29 
30 #if !defined(lint)
31 __RCSID("$NetBSD: rumpuser_pth.c,v 1.12 2013/02/11 16:02:31 pooka Exp $");
32 #endif /* !lint */
33 
34 #include <assert.h>
35 #include <errno.h>
36 #include <fcntl.h>
37 #include <pthread.h>
38 #include <stdlib.h>
39 #include <stdio.h>
40 #include <string.h>
41 #include <stdint.h>
42 #include <unistd.h>
43 
44 #include <rump/rumpuser.h>
45 
46 #include "rumpuser_int.h"
47 
48 static pthread_key_t curlwpkey;
49 
50 #define NOFAIL(a) do {if (!(a)) abort();} while (/*CONSTCOND*/0)
51 #define NOFAIL_ERRNO(a)							\
52 do {									\
53 	int fail_rv = (a);						\
54 	if (fail_rv) {							\
55 		printf("panic: rumpuser fatal failure %d (%s)\n",	\
56 		    fail_rv, strerror(fail_rv));			\
57 		abort();						\
58 	}								\
59 } while (/*CONSTCOND*/0)
60 
61 struct rumpuser_mtx {
62 	pthread_mutex_t pthmtx;
63 	struct lwp *owner;
64 	int iskmutex;
65 };
66 
67 #define RURW_AMWRITER(rw) (rw->writer == rumpuser_get_curlwp()		\
68 				&& rw->readers == -1)
69 #define RURW_HASREAD(rw)  (rw->readers > 0)
70 
71 #define RURW_SETWRITE(rw)						\
72 do {									\
73 	assert(rw->readers == 0);					\
74 	rw->writer = rumpuser_get_curlwp();				\
75 	rw->readers = -1;						\
76 } while (/*CONSTCOND*/0)
77 #define RURW_CLRWRITE(rw)						\
78 do {									\
79 	assert(rw->readers == -1 && RURW_AMWRITER(rw));			\
80 	rw->readers = 0;						\
81 } while (/*CONSTCOND*/0)
82 #define RURW_INCREAD(rw)						\
83 do {									\
84 	pthread_spin_lock(&rw->spin);					\
85 	assert(rw->readers >= 0);					\
86 	++(rw)->readers;						\
87 	pthread_spin_unlock(&rw->spin);					\
88 } while (/*CONSTCOND*/0)
89 #define RURW_DECREAD(rw)						\
90 do {									\
91 	pthread_spin_lock(&rw->spin);					\
92 	assert(rw->readers > 0);					\
93 	--(rw)->readers;						\
94 	pthread_spin_unlock(&rw->spin);					\
95 } while (/*CONSTCOND*/0)
96 
97 struct rumpuser_rw {
98 	pthread_rwlock_t pthrw;
99 	pthread_spinlock_t spin;
100 	int readers;
101 	struct lwp *writer;
102 };
103 
104 struct rumpuser_cv {
105 	pthread_cond_t pthcv;
106 	int nwaiters;
107 };
108 
109 struct rumpuser_mtx rumpuser_aio_mtx;
110 struct rumpuser_cv rumpuser_aio_cv;
111 int rumpuser_aio_head, rumpuser_aio_tail;
112 struct rumpuser_aio rumpuser_aios[N_AIOS];
113 
114 kernel_lockfn	rumpuser__klock;
115 kernel_unlockfn	rumpuser__kunlock;
116 int		rumpuser__wantthreads;
117 
118 void
119 /*ARGSUSED*/
120 rumpuser_biothread(void *arg)
121 {
122 	struct rumpuser_aio *rua;
123 	rump_biodone_fn biodone = arg;
124 	ssize_t rv;
125 	int error, dummy;
126 
127 	/* unschedule from CPU.  we reschedule before running the interrupt */
128 	rumpuser__kunlock(0, &dummy, NULL);
129 	assert(dummy == 0);
130 
131 	NOFAIL_ERRNO(pthread_mutex_lock(&rumpuser_aio_mtx.pthmtx));
132 	for (;;) {
133 		while (rumpuser_aio_head == rumpuser_aio_tail) {
134 			NOFAIL_ERRNO(pthread_cond_wait(&rumpuser_aio_cv.pthcv,
135 			    &rumpuser_aio_mtx.pthmtx));
136 		}
137 
138 		rua = &rumpuser_aios[rumpuser_aio_tail];
139 		assert(rua->rua_bp != NULL);
140 		pthread_mutex_unlock(&rumpuser_aio_mtx.pthmtx);
141 
142 		if (rua->rua_op & RUA_OP_READ) {
143 			error = 0;
144 			rv = pread(rua->rua_fd, rua->rua_data,
145 			    rua->rua_dlen, rua->rua_off);
146 			if (rv < 0) {
147 				rv = 0;
148 				error = errno;
149 			}
150 		} else {
151 			error = 0;
152 			rv = pwrite(rua->rua_fd, rua->rua_data,
153 			    rua->rua_dlen, rua->rua_off);
154 			if (rv < 0) {
155 				rv = 0;
156 				error = errno;
157 			} else if (rua->rua_op & RUA_OP_SYNC) {
158 #ifdef __NetBSD__
159 				fsync_range(rua->rua_fd, FDATASYNC,
160 				    rua->rua_off, rua->rua_dlen);
161 #else
162 				fsync(rua->rua_fd);
163 #endif
164 			}
165 		}
166 		rumpuser__klock(0, NULL);
167 		biodone(rua->rua_bp, (size_t)rv, error);
168 		rumpuser__kunlock(0, &dummy, NULL);
169 
170 		rua->rua_bp = NULL;
171 
172 		NOFAIL_ERRNO(pthread_mutex_lock(&rumpuser_aio_mtx.pthmtx));
173 		rumpuser_aio_tail = (rumpuser_aio_tail+1) % N_AIOS;
174 		pthread_cond_signal(&rumpuser_aio_cv.pthcv);
175 	}
176 
177 	/*NOTREACHED*/
178 	fprintf(stderr, "error: rumpuser_biothread reached unreachable\n");
179 	abort();
180 }
181 
182 void
183 rumpuser_thrinit(kernel_lockfn lockfn, kernel_unlockfn unlockfn, int threads)
184 {
185 #ifdef RUMPUSER_USE_RANDOM
186 	/* XXX: there's no rumpuser_bootstrap, so do this here */
187 	uint32_t rv;
188 	int fd;
189 
190 	if ((fd = open("/dev/urandom", O_RDONLY)) == -1) {
191 		srandom(time(NULL));
192 	} else {
193 		if (read(fd, &rv, sizeof(rv)) != sizeof(rv))
194 			srandom(time(NULL));
195 		else
196 			srandom(rv);
197 		close(fd);
198 	}
199 #endif
200 
201 	pthread_mutex_init(&rumpuser_aio_mtx.pthmtx, NULL);
202 	pthread_cond_init(&rumpuser_aio_cv.pthcv, NULL);
203 
204 	pthread_key_create(&curlwpkey, NULL);
205 
206 	rumpuser__klock = lockfn;
207 	rumpuser__kunlock = unlockfn;
208 	rumpuser__wantthreads = threads;
209 }
210 
211 #if 0
212 void
213 rumpuser__thrdestroy(void)
214 {
215 
216 	pthread_key_delete(curlwpkey);
217 }
218 #endif
219 
220 int
221 rumpuser_thread_create(void *(*f)(void *), void *arg, const char *thrname,
222 	int joinable, void **ptcookie)
223 {
224 	pthread_t ptid;
225 	pthread_t *ptidp;
226 	pthread_attr_t pattr;
227 	int rv;
228 
229 	if ((rv = pthread_attr_init(&pattr)) != 0)
230 		return rv;
231 
232 	if (joinable) {
233 		NOFAIL(ptidp = malloc(sizeof(*ptidp)));
234 		pthread_attr_setdetachstate(&pattr, PTHREAD_CREATE_JOINABLE);
235 	} else {
236 		ptidp = &ptid;
237 		pthread_attr_setdetachstate(&pattr, PTHREAD_CREATE_DETACHED);
238 	}
239 
240 	rv = pthread_create(ptidp, &pattr, f, arg);
241 #if defined(__NetBSD__)
242 	if (rv == 0 && thrname)
243 		pthread_setname_np(ptid, thrname, NULL);
244 #elif defined(__linux__)
245 	/*
246 	 * The pthread_setname_np() call varies from one Linux distro to
247 	 * another.  Comment out the call pending autoconf support.
248 	 */
249 #if 0
250 	if (rv == 0 && thrname)
251 		pthread_setname_np(ptid, thrname);
252 #endif
253 #endif
254 
255 	if (joinable) {
256 		assert(ptcookie);
257 		*ptcookie = ptidp;
258 	}
259 
260 	pthread_attr_destroy(&pattr);
261 
262 	return rv;
263 }
264 
265 __dead void
266 rumpuser_thread_exit(void)
267 {
268 
269 	pthread_exit(NULL);
270 }
271 
272 int
273 rumpuser_thread_join(void *ptcookie)
274 {
275 	pthread_t *pt = ptcookie;
276 	int rv;
277 
278 	KLOCK_WRAP((rv = pthread_join(*pt, NULL)));
279 	if (rv == 0)
280 		free(pt);
281 
282 	return rv;
283 }
284 
285 void
286 rumpuser_mutex_init(struct rumpuser_mtx **mtx)
287 {
288 	pthread_mutexattr_t att;
289 
290 	NOFAIL(*mtx = malloc(sizeof(struct rumpuser_mtx)));
291 
292 	pthread_mutexattr_init(&att);
293 	pthread_mutexattr_settype(&att, PTHREAD_MUTEX_ERRORCHECK);
294 	NOFAIL_ERRNO(pthread_mutex_init(&((*mtx)->pthmtx), &att));
295 	pthread_mutexattr_destroy(&att);
296 
297 	(*mtx)->owner = NULL;
298 	(*mtx)->iskmutex = 0;
299 }
300 
301 void
302 rumpuser_mutex_init_kmutex(struct rumpuser_mtx **mtx)
303 {
304 
305 	rumpuser_mutex_init(mtx);
306 	(*mtx)->iskmutex = 1;
307 }
308 
309 static void
310 mtxenter(struct rumpuser_mtx *mtx)
311 {
312 
313 	if (!mtx->iskmutex)
314 		return;
315 
316 	assert(mtx->owner == NULL);
317 	mtx->owner = rumpuser_get_curlwp();
318 }
319 
320 static void
321 mtxexit(struct rumpuser_mtx *mtx)
322 {
323 
324 	if (!mtx->iskmutex)
325 		return;
326 
327 	assert(mtx->owner != NULL);
328 	mtx->owner = NULL;
329 }
330 
331 void
332 rumpuser_mutex_enter(struct rumpuser_mtx *mtx)
333 {
334 
335 	if (pthread_mutex_trylock(&mtx->pthmtx) != 0)
336 		KLOCK_WRAP(NOFAIL_ERRNO(pthread_mutex_lock(&mtx->pthmtx)));
337 	mtxenter(mtx);
338 }
339 
340 void
341 rumpuser_mutex_enter_nowrap(struct rumpuser_mtx *mtx)
342 {
343 
344 	NOFAIL_ERRNO(pthread_mutex_lock(&mtx->pthmtx));
345 	mtxenter(mtx);
346 }
347 
348 int
349 rumpuser_mutex_tryenter(struct rumpuser_mtx *mtx)
350 {
351 	int rv;
352 
353 	rv = pthread_mutex_trylock(&mtx->pthmtx);
354 	if (rv == 0) {
355 		mtxenter(mtx);
356 	}
357 
358 	return rv == 0;
359 }
360 
361 void
362 rumpuser_mutex_exit(struct rumpuser_mtx *mtx)
363 {
364 
365 	mtxexit(mtx);
366 	NOFAIL_ERRNO(pthread_mutex_unlock(&mtx->pthmtx));
367 }
368 
369 void
370 rumpuser_mutex_destroy(struct rumpuser_mtx *mtx)
371 {
372 
373 	NOFAIL_ERRNO(pthread_mutex_destroy(&mtx->pthmtx));
374 	free(mtx);
375 }
376 
377 struct lwp *
378 rumpuser_mutex_owner(struct rumpuser_mtx *mtx)
379 {
380 
381 	if (__predict_false(!mtx->iskmutex)) {
382 		printf("panic: rumpuser_mutex_held unsupported on non-kmtx\n");
383 		abort();
384 	}
385 
386 	return mtx->owner;
387 }
388 
389 void
390 rumpuser_rw_init(struct rumpuser_rw **rw)
391 {
392 
393 	NOFAIL(*rw = malloc(sizeof(struct rumpuser_rw)));
394 	NOFAIL_ERRNO(pthread_rwlock_init(&((*rw)->pthrw), NULL));
395 	NOFAIL_ERRNO(pthread_spin_init(&((*rw)->spin),PTHREAD_PROCESS_PRIVATE));
396 	(*rw)->readers = 0;
397 	(*rw)->writer = NULL;
398 }
399 
400 void
401 rumpuser_rw_enter(struct rumpuser_rw *rw, int iswrite)
402 {
403 
404 	if (iswrite) {
405 		if (pthread_rwlock_trywrlock(&rw->pthrw) != 0)
406 			KLOCK_WRAP(NOFAIL_ERRNO(
407 			    pthread_rwlock_wrlock(&rw->pthrw)));
408 		RURW_SETWRITE(rw);
409 	} else {
410 		if (pthread_rwlock_tryrdlock(&rw->pthrw) != 0)
411 			KLOCK_WRAP(NOFAIL_ERRNO(
412 			    pthread_rwlock_rdlock(&rw->pthrw)));
413 		RURW_INCREAD(rw);
414 	}
415 }
416 
417 int
418 rumpuser_rw_tryenter(struct rumpuser_rw *rw, int iswrite)
419 {
420 	int rv;
421 
422 	if (iswrite) {
423 		rv = pthread_rwlock_trywrlock(&rw->pthrw);
424 		if (rv == 0)
425 			RURW_SETWRITE(rw);
426 	} else {
427 		rv = pthread_rwlock_tryrdlock(&rw->pthrw);
428 		if (rv == 0)
429 			RURW_INCREAD(rw);
430 	}
431 
432 	return rv == 0;
433 }
434 
435 void
436 rumpuser_rw_exit(struct rumpuser_rw *rw)
437 {
438 
439 	if (RURW_HASREAD(rw))
440 		RURW_DECREAD(rw);
441 	else
442 		RURW_CLRWRITE(rw);
443 	NOFAIL_ERRNO(pthread_rwlock_unlock(&rw->pthrw));
444 }
445 
446 void
447 rumpuser_rw_destroy(struct rumpuser_rw *rw)
448 {
449 
450 	NOFAIL_ERRNO(pthread_rwlock_destroy(&rw->pthrw));
451 	NOFAIL_ERRNO(pthread_spin_destroy(&rw->spin));
452 	free(rw);
453 }
454 
455 int
456 rumpuser_rw_held(struct rumpuser_rw *rw)
457 {
458 
459 	return rw->readers != 0;
460 }
461 
462 int
463 rumpuser_rw_rdheld(struct rumpuser_rw *rw)
464 {
465 
466 	return RURW_HASREAD(rw);
467 }
468 
469 int
470 rumpuser_rw_wrheld(struct rumpuser_rw *rw)
471 {
472 
473 	return RURW_AMWRITER(rw);
474 }
475 
476 void
477 rumpuser_cv_init(struct rumpuser_cv **cv)
478 {
479 
480 	NOFAIL(*cv = malloc(sizeof(struct rumpuser_cv)));
481 	NOFAIL_ERRNO(pthread_cond_init(&((*cv)->pthcv), NULL));
482 	(*cv)->nwaiters = 0;
483 }
484 
485 void
486 rumpuser_cv_destroy(struct rumpuser_cv *cv)
487 {
488 
489 	NOFAIL_ERRNO(pthread_cond_destroy(&cv->pthcv));
490 	free(cv);
491 }
492 
493 void
494 rumpuser_cv_wait(struct rumpuser_cv *cv, struct rumpuser_mtx *mtx)
495 {
496 	int nlocks;
497 
498 	cv->nwaiters++;
499 	rumpuser__kunlock(0, &nlocks, mtx);
500 	mtxexit(mtx);
501 	NOFAIL_ERRNO(pthread_cond_wait(&cv->pthcv, &mtx->pthmtx));
502 	mtxenter(mtx);
503 	rumpuser__klock(nlocks, mtx);
504 	cv->nwaiters--;
505 }
506 
507 void
508 rumpuser_cv_wait_nowrap(struct rumpuser_cv *cv, struct rumpuser_mtx *mtx)
509 {
510 
511 	cv->nwaiters++;
512 	mtxexit(mtx);
513 	NOFAIL_ERRNO(pthread_cond_wait(&cv->pthcv, &mtx->pthmtx));
514 	mtxenter(mtx);
515 	cv->nwaiters--;
516 }
517 
518 int
519 rumpuser_cv_timedwait(struct rumpuser_cv *cv, struct rumpuser_mtx *mtx,
520 	int64_t sec, int64_t nsec)
521 {
522 	struct timespec ts;
523 	int rv, nlocks;
524 
525 	/* LINTED */
526 	ts.tv_sec = sec; ts.tv_nsec = nsec;
527 
528 	cv->nwaiters++;
529 	rumpuser__kunlock(0, &nlocks, mtx);
530 	mtxexit(mtx);
531 	rv = pthread_cond_timedwait(&cv->pthcv, &mtx->pthmtx, &ts);
532 	mtxenter(mtx);
533 	rumpuser__klock(nlocks, mtx);
534 	cv->nwaiters--;
535 	if (rv != 0 && rv != ETIMEDOUT)
536 		abort();
537 
538 	return rv == ETIMEDOUT;
539 }
540 
541 void
542 rumpuser_cv_signal(struct rumpuser_cv *cv)
543 {
544 
545 	NOFAIL_ERRNO(pthread_cond_signal(&cv->pthcv));
546 }
547 
548 void
549 rumpuser_cv_broadcast(struct rumpuser_cv *cv)
550 {
551 
552 	NOFAIL_ERRNO(pthread_cond_broadcast(&cv->pthcv));
553 }
554 
555 int
556 rumpuser_cv_has_waiters(struct rumpuser_cv *cv)
557 {
558 
559 	return cv->nwaiters;
560 }
561 
562 /*
563  * curlwp
564  */
565 
566 void
567 rumpuser_set_curlwp(struct lwp *l)
568 {
569 
570 	assert(pthread_getspecific(curlwpkey) == NULL || l == NULL);
571 	pthread_setspecific(curlwpkey, l);
572 }
573 
574 struct lwp *
575 rumpuser_get_curlwp(void)
576 {
577 
578 	return pthread_getspecific(curlwpkey);
579 }
580