xref: /netbsd-src/tests/lib/libc/sys/t_eventfd.c (revision f92afe1eb4dde9922857aa47f518915dd9265b3a)
1 /* $NetBSD: t_eventfd.c,v 1.3 2022/02/20 15:21:14 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 2020 The NetBSD Foundation, Inc.
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  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __COPYRIGHT("@(#) Copyright (c) 2020\
31  The NetBSD Foundation, inc. All rights reserved.");
32 __RCSID("$NetBSD: t_eventfd.c,v 1.3 2022/02/20 15:21:14 thorpej Exp $");
33 
34 #include <sys/types.h>
35 #include <sys/event.h>
36 #include <sys/eventfd.h>
37 #include <sys/ioctl.h>
38 #include <sys/select.h>
39 #include <sys/stat.h>
40 #include <sys/syscall.h>
41 #include <errno.h>
42 #include <poll.h>
43 #include <pthread.h>
44 #include <stdlib.h>
45 #include <stdio.h>
46 #include <time.h>
47 #include <unistd.h>
48 
49 #include <atf-c.h>
50 
51 struct helper_context {
52 	int	efd;
53 
54 	pthread_mutex_t mutex;
55 	pthread_cond_t cond;
56 	pthread_barrier_t barrier;
57 	int	state;
58 };
59 
60 static void
init_helper_context(struct helper_context * const ctx)61 init_helper_context(struct helper_context * const ctx)
62 {
63 	pthread_condattr_t condattr;
64 
65 	memset(ctx, 0, sizeof(*ctx));
66 
67 	ATF_REQUIRE(pthread_mutex_init(&ctx->mutex, NULL) == 0);
68 
69 	ATF_REQUIRE(pthread_condattr_init(&condattr) == 0);
70 	ATF_REQUIRE(pthread_condattr_setclock(&condattr, CLOCK_MONOTONIC) == 0);
71 	ATF_REQUIRE(pthread_cond_init(&ctx->cond, &condattr) == 0);
72 	ATF_REQUIRE(pthread_condattr_destroy(&condattr) == 0);
73 
74 	ATF_REQUIRE(pthread_barrier_init(&ctx->barrier, NULL, 2) == 0);
75 }
76 
77 static void
set_state(struct helper_context * const ctx,int const new)78 set_state(struct helper_context * const ctx, int const new)
79 {
80 	pthread_mutex_lock(&ctx->mutex);
81 	ctx->state = new;
82 	pthread_cond_signal(&ctx->cond);
83 	pthread_mutex_unlock(&ctx->mutex);
84 }
85 
86 static int
get_state(struct helper_context * const ctx)87 get_state(struct helper_context * const ctx)
88 {
89 	int rv;
90 
91 	pthread_mutex_lock(&ctx->mutex);
92 	rv = ctx->state;
93 	pthread_mutex_unlock(&ctx->mutex);
94 
95 	return rv;
96 }
97 
98 static bool
wait_state(struct helper_context * const ctx,int const val)99 wait_state(struct helper_context * const ctx, int const val)
100 {
101 	struct timespec deadline;
102 	int error;
103 	bool rv;
104 
105 	pthread_mutex_lock(&ctx->mutex);
106 
107 	ATF_REQUIRE(clock_gettime(CLOCK_MONOTONIC, &deadline) == 0);
108 	deadline.tv_sec += 5;
109 
110 	while (ctx->state != val) {
111 		error = pthread_cond_timedwait(&ctx->cond, &ctx->mutex,
112 		    &deadline);
113 		if (error) {
114 			break;
115 		}
116 	}
117 	rv = ctx->state == val;
118 
119 	pthread_mutex_unlock(&ctx->mutex);
120 
121 	return rv;
122 }
123 
124 static bool
wait_barrier(struct helper_context * const ctx)125 wait_barrier(struct helper_context * const ctx)
126 {
127 	int rv = pthread_barrier_wait(&ctx->barrier);
128 
129 	return rv == 0 || rv == PTHREAD_BARRIER_SERIAL_THREAD;
130 }
131 
132 /*****************************************************************************/
133 
134 static void *
eventfd_normal_helper(void * const v)135 eventfd_normal_helper(void * const v)
136 {
137 	struct helper_context * const ctx = v;
138 	eventfd_t efd_value;
139 
140 	ATF_REQUIRE(wait_barrier(ctx));
141 
142 	/* Read the value.  This will reset it to zero. */
143 	ATF_REQUIRE(get_state(ctx) == 666);
144 	ATF_REQUIRE(eventfd_read(ctx->efd, &efd_value) == 0);
145 
146 	/* Assert the value. */
147 	ATF_REQUIRE(efd_value == 0xcafebabe);
148 
149 	set_state(ctx, 0);
150 
151 	/* Wait for the main thread to prep the next test. */
152 	ATF_REQUIRE(wait_barrier(ctx));
153 
154 	/* Read the value. */
155 	ATF_REQUIRE(eventfd_read(ctx->efd, &efd_value) == 0);
156 
157 	/* Assert the value. */
158 	ATF_REQUIRE(efd_value == 0xbeefcafe);
159 
160 	ATF_REQUIRE(wait_barrier(ctx));
161 
162 	return NULL;
163 }
164 
165 ATF_TC(eventfd_normal);
ATF_TC_HEAD(eventfd_normal,tc)166 ATF_TC_HEAD(eventfd_normal, tc)
167 {
168 	atf_tc_set_md_var(tc, "descr",
169 	    "validates basic normal eventfd operation");
170 }
ATF_TC_BODY(eventfd_normal,tc)171 ATF_TC_BODY(eventfd_normal, tc)
172 {
173 	struct helper_context ctx;
174 	pthread_t helper;
175 	void *join_val;
176 
177 	init_helper_context(&ctx);
178 
179 	ATF_REQUIRE((ctx.efd = eventfd(0, 0)) >= 0);
180 
181 	ATF_REQUIRE(pthread_create(&helper, NULL,
182 				   eventfd_normal_helper, &ctx) == 0);
183 
184 	/*
185 	 * Wait for the helper to block in read().  Give it some time
186 	 * so that if the read fails or returns immediately, we'll
187 	 * notice.
188 	 */
189 	set_state(&ctx, 666);
190 	ATF_REQUIRE(wait_barrier(&ctx));
191 	sleep(2);
192 	ATF_REQUIRE(get_state(&ctx) == 666);
193 
194 	/* Write a distinct value; helper will assert it. */
195 	ATF_REQUIRE(eventfd_write(ctx.efd, 0xcafebabe) == 0);
196 
197 	/* Wait for helper to read the value. */
198 	ATF_REQUIRE(wait_state(&ctx, 0));
199 
200 	/* Helper is now blocked in a barrier. */
201 
202 	/* Test additive property of the efd value. */
203 	ATF_REQUIRE(eventfd_write(ctx.efd, 0x0000cafe) == 0);
204 	ATF_REQUIRE(eventfd_write(ctx.efd, 0xbeef0000) == 0);
205 
206 	/* Satisfy the barrier; helper will read value and assert 0xbeefcafe. */
207 	ATF_REQUIRE(wait_barrier(&ctx));
208 
209 	/* And wait for it to finish. */
210 	ATF_REQUIRE(wait_barrier(&ctx));
211 
212 	/* Reap the helper. */
213 	ATF_REQUIRE(pthread_join(helper, &join_val) == 0);
214 
215 	(void) close(ctx.efd);
216 }
217 
218 /*****************************************************************************/
219 
220 ATF_TC(eventfd_semaphore);
ATF_TC_HEAD(eventfd_semaphore,tc)221 ATF_TC_HEAD(eventfd_semaphore, tc)
222 {
223 	atf_tc_set_md_var(tc, "descr",
224 	    "validates semaphore and non-blocking eventfd operation");
225 }
ATF_TC_BODY(eventfd_semaphore,tc)226 ATF_TC_BODY(eventfd_semaphore, tc)
227 {
228 	eventfd_t efd_value;
229 	int efd;
230 
231 	ATF_REQUIRE((efd = eventfd(3, EFD_SEMAPHORE | EFD_NONBLOCK)) >= 0);
232 
233 	/* 3 reads should succeed without blocking. */
234 	ATF_REQUIRE(eventfd_read(efd, &efd_value) == 0);
235 	ATF_REQUIRE(efd_value == 1);
236 
237 	ATF_REQUIRE(eventfd_read(efd, &efd_value) == 0);
238 	ATF_REQUIRE(efd_value == 1);
239 
240 	ATF_REQUIRE(eventfd_read(efd, &efd_value) == 0);
241 	ATF_REQUIRE(efd_value == 1);
242 
243 	/* This one should block. */
244 	ATF_REQUIRE_ERRNO(EAGAIN,
245 	    eventfd_read(efd, &efd_value) == -1);
246 
247 	/* Add 1 to the semaphore. */
248 	ATF_REQUIRE(eventfd_write(efd, 1) == 0);
249 
250 	/* One more read allowed. */
251 	ATF_REQUIRE(eventfd_read(efd, &efd_value) == 0);
252 	ATF_REQUIRE(efd_value == 1);
253 
254 	/* And this one again should block. */
255 	ATF_REQUIRE_ERRNO(EAGAIN,
256 	    eventfd_read(efd, &efd_value) == -1);
257 
258 	(void) close(efd);
259 }
260 
261 /*****************************************************************************/
262 
263 ATF_TC(eventfd_select_poll_kevent_immed);
ATF_TC_HEAD(eventfd_select_poll_kevent_immed,tc)264 ATF_TC_HEAD(eventfd_select_poll_kevent_immed, tc)
265 {
266 	atf_tc_set_md_var(tc, "descr",
267 	    "validates select/poll/kevent behavior - immediate return");
268 }
ATF_TC_BODY(eventfd_select_poll_kevent_immed,tc)269 ATF_TC_BODY(eventfd_select_poll_kevent_immed, tc)
270 {
271 	const struct timespec ts = { .tv_sec = 0, .tv_nsec = 0 };
272 	struct timeval tv;
273 	struct pollfd fds[1];
274 	fd_set readfds, writefds, exceptfds;
275 	int efd;
276 	int kq;
277 	struct kevent kev[2];
278 
279 	ATF_REQUIRE((efd = eventfd(0, EFD_NONBLOCK)) >= 0);
280 
281 	ATF_REQUIRE((kq = kqueue()) >= 0);
282 	EV_SET(&kev[0], efd, EVFILT_READ, EV_ADD, 0, 0, NULL);
283 	EV_SET(&kev[1], efd, EVFILT_WRITE, EV_ADD, 0, 0, NULL);
284 	ATF_REQUIRE(kevent(kq, kev, 2, NULL, 0, &ts) == 0);
285 
286 	/*
287 	 * efd should be writable but not readable.  Pass all of the
288 	 * event bits; we should only get back POLLOUT | POLLWRNORM.
289 	 */
290 	fds[0].fd = efd;
291 	fds[0].events = POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI |
292 	    POLLOUT | POLLWRNORM | POLLWRBAND | POLLHUP;
293 	fds[0].revents = 0;
294 	ATF_REQUIRE(poll(fds, 1, 0) == 1);
295 	ATF_REQUIRE(fds[0].revents == (POLLOUT | POLLWRNORM));
296 
297 	/*
298 	 * As above; efd should only be set in writefds upon return
299 	 * from the select() call.
300 	 */
301 	FD_ZERO(&readfds);
302 	FD_ZERO(&writefds);
303 	FD_ZERO(&exceptfds);
304 	tv.tv_sec = 0;
305 	tv.tv_usec = 0;
306 	FD_SET(efd, &readfds);
307 	FD_SET(efd, &writefds);
308 	FD_SET(efd, &exceptfds);
309 	ATF_REQUIRE(select(efd + 1, &readfds, &writefds, &exceptfds, &tv) == 1);
310 	ATF_REQUIRE(!FD_ISSET(efd, &readfds));
311 	ATF_REQUIRE(FD_ISSET(efd, &writefds));
312 	ATF_REQUIRE(!FD_ISSET(efd, &exceptfds));
313 
314 	/*
315 	 * Check that we get an EVFILT_WRITE event (and only that event)
316 	 * on efd.
317 	 */
318 	memset(kev, 0, sizeof(kev));
319 	ATF_REQUIRE(kevent(kq, NULL, 0, kev, 2, &ts) == 1);
320 	ATF_REQUIRE(kev[0].ident == (uintptr_t)efd);
321 	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
322 	ATF_REQUIRE((kev[0].flags & (EV_EOF | EV_ERROR)) == 0);
323 	ATF_REQUIRE(kev[0].data == 0);
324 
325 	/*
326 	 * Write the maximum value into the eventfd.  This should result
327 	 * in the eventfd becoming readable but NOT writable.
328 	 */
329 	ATF_REQUIRE(eventfd_write(efd, UINT64_MAX - 1) == 0);
330 
331 	fds[0].fd = efd;
332 	fds[0].events = POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI |
333 	    POLLOUT | POLLWRNORM | POLLWRBAND | POLLHUP;
334 	fds[0].revents = 0;
335 	ATF_REQUIRE(poll(fds, 1, 0) == 1);
336 	ATF_REQUIRE(fds[0].revents == (POLLIN | POLLRDNORM));
337 
338 	FD_ZERO(&readfds);
339 	FD_ZERO(&writefds);
340 	FD_ZERO(&exceptfds);
341 	tv.tv_sec = 0;
342 	tv.tv_usec = 0;
343 	FD_SET(efd, &readfds);
344 	FD_SET(efd, &writefds);
345 	FD_SET(efd, &exceptfds);
346 	ATF_REQUIRE(select(efd + 1, &readfds, &writefds, &exceptfds, &tv) == 1);
347 	ATF_REQUIRE(FD_ISSET(efd, &readfds));
348 	ATF_REQUIRE(!FD_ISSET(efd, &writefds));
349 	ATF_REQUIRE(!FD_ISSET(efd, &exceptfds));
350 
351 	/*
352 	 * Check that we get an EVFILT_READ event (and only that event)
353 	 * on efd.
354 	 */
355 	memset(kev, 0, sizeof(kev));
356 	ATF_REQUIRE(kevent(kq, NULL, 0, kev, 2, &ts) == 1);
357 	ATF_REQUIRE(kev[0].ident == (uintptr_t)efd);
358 	ATF_REQUIRE(kev[0].filter == EVFILT_READ);
359 	ATF_REQUIRE((kev[0].flags & (EV_EOF | EV_ERROR)) == 0);
360 	ATF_REQUIRE(kev[0].data == (int64_t)(UINT64_MAX - 1));
361 
362 	(void) close(kq);
363 	(void) close(efd);
364 }
365 
366 /*****************************************************************************/
367 
368 static void *
eventfd_select_poll_kevent_block_helper(void * const v)369 eventfd_select_poll_kevent_block_helper(void * const v)
370 {
371 	struct helper_context * const ctx = v;
372 	struct pollfd fds[1];
373 	fd_set selfds;
374 	eventfd_t efd_value;
375 	int kq;
376 	struct kevent kev[1];
377 
378 	fds[0].fd = ctx->efd;
379 	fds[0].events = POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI;
380 	fds[0].revents = 0;
381 
382 	ATF_REQUIRE_ERRNO(EAGAIN,
383 	    eventfd_read(ctx->efd, &efd_value) == -1);
384 
385 	ATF_REQUIRE(wait_barrier(ctx));
386 
387 	ATF_REQUIRE(get_state(ctx) == 666);
388 	ATF_REQUIRE(poll(fds, 1, INFTIM) == 1);
389 	ATF_REQUIRE(fds[0].revents == (POLLIN | POLLRDNORM));
390 	set_state(ctx, 0);
391 
392 	ATF_REQUIRE(wait_barrier(ctx));
393 
394 	/*
395 	 * The maximum value was written to the eventfd, so we
396 	 * should block waiting for writability.
397 	 */
398 	fds[0].fd = ctx->efd;
399 	fds[0].events = POLLOUT | POLLWRNORM;
400 	fds[0].revents = 0;
401 
402 	ATF_REQUIRE_ERRNO(EAGAIN,
403 	    eventfd_write(ctx->efd, UINT64_MAX - 1) == -1);
404 
405 	ATF_REQUIRE(wait_barrier(ctx));
406 
407 	ATF_REQUIRE(get_state(ctx) == 666);
408 	ATF_REQUIRE(poll(fds, 1, INFTIM) == 1);
409 	ATF_REQUIRE(fds[0].revents == (POLLOUT | POLLWRNORM));
410 	set_state(ctx, 0);
411 
412 	ATF_REQUIRE(wait_barrier(ctx));
413 
414 	/*
415 	 * Now, the same dance again, with select().
416 	 */
417 
418 	FD_ZERO(&selfds);
419 	FD_SET(ctx->efd, &selfds);
420 
421 	ATF_REQUIRE_ERRNO(EAGAIN,
422 	    eventfd_read(ctx->efd, &efd_value) == -1);
423 
424 	ATF_REQUIRE(wait_barrier(ctx));
425 
426 	ATF_REQUIRE(get_state(ctx) == 666);
427 	ATF_REQUIRE(select(ctx->efd + 1, &selfds, NULL, NULL, NULL) == 1);
428 	ATF_REQUIRE(FD_ISSET(ctx->efd, &selfds));
429 	set_state(ctx, 0);
430 
431 	ATF_REQUIRE(wait_barrier(ctx));
432 
433 	FD_ZERO(&selfds);
434 	FD_SET(ctx->efd, &selfds);
435 
436 	ATF_REQUIRE_ERRNO(EAGAIN,
437 	    eventfd_write(ctx->efd, UINT64_MAX - 1) == -1);
438 
439 	ATF_REQUIRE(wait_barrier(ctx));
440 
441 	ATF_REQUIRE(get_state(ctx) == 666);
442 	ATF_REQUIRE(select(ctx->efd + 1, NULL, &selfds, NULL, NULL) == 1);
443 	ATF_REQUIRE(FD_ISSET(ctx->efd, &selfds));
444 	set_state(ctx, 0);
445 
446 	ATF_REQUIRE(wait_barrier(ctx));
447 
448 	/*
449 	 * Now, the same dance again, with kevent().
450 	 */
451 	ATF_REQUIRE((kq = kqueue()) >= 0);
452 
453 	EV_SET(&kev[0], ctx->efd, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, NULL);
454 	ATF_REQUIRE(kevent(kq, kev, 1, NULL, 0, NULL) == 0);
455 
456 	ATF_REQUIRE_ERRNO(EAGAIN,
457 	    eventfd_read(ctx->efd, &efd_value) == -1);
458 
459 	ATF_REQUIRE(wait_barrier(ctx));
460 
461 	ATF_REQUIRE(get_state(ctx) == 666);
462 	ATF_REQUIRE(kevent(kq, NULL, 0, kev, 1, NULL) == 1);
463 	ATF_REQUIRE(kev[0].ident == (uintptr_t)ctx->efd);
464 	ATF_REQUIRE(kev[0].filter == EVFILT_READ);
465 	ATF_REQUIRE((kev[0].flags & (EV_EOF | EV_ERROR)) == 0);
466 	ATF_REQUIRE(kev[0].data == (int64_t)(UINT64_MAX - 1));
467 	set_state(ctx, 0);
468 
469 	ATF_REQUIRE(wait_barrier(ctx));
470 
471 	EV_SET(&kev[0], ctx->efd, EVFILT_WRITE, EV_ADD | EV_ONESHOT, 0, 0,
472 	       NULL);
473 	ATF_REQUIRE(kevent(kq, kev, 1, NULL, 0, NULL) == 0);
474 
475 	ATF_REQUIRE_ERRNO(EAGAIN,
476 	    eventfd_write(ctx->efd, UINT64_MAX - 1) == -1);
477 
478 	ATF_REQUIRE(wait_barrier(ctx));
479 
480 	ATF_REQUIRE(get_state(ctx) == 666);
481 	ATF_REQUIRE(kevent(kq, NULL, 0, kev, 1, NULL) == 1);
482 	ATF_REQUIRE(kev[0].ident == (uintptr_t)ctx->efd);
483 	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
484 	ATF_REQUIRE((kev[0].flags & (EV_EOF | EV_ERROR)) == 0);
485 	ATF_REQUIRE(kev[0].data == 0);
486 	set_state(ctx, 0);
487 
488 	ATF_REQUIRE(wait_barrier(ctx));
489 
490 	(void) close(kq);
491 
492 	return NULL;
493 }
494 
495 ATF_TC(eventfd_select_poll_kevent_block);
ATF_TC_HEAD(eventfd_select_poll_kevent_block,tc)496 ATF_TC_HEAD(eventfd_select_poll_kevent_block, tc)
497 {
498 	atf_tc_set_md_var(tc, "descr",
499 	    "validates select/poll/kevent behavior - return after blocking");
500 }
ATF_TC_BODY(eventfd_select_poll_kevent_block,tc)501 ATF_TC_BODY(eventfd_select_poll_kevent_block, tc)
502 {
503 	struct helper_context ctx;
504 	pthread_t helper;
505 	eventfd_t efd_value;
506 	void *join_val;
507 
508 	init_helper_context(&ctx);
509 
510 	ATF_REQUIRE((ctx.efd = eventfd(0, EFD_NONBLOCK)) >= 0);
511 
512 	ATF_REQUIRE(pthread_create(&helper, NULL,
513 				   eventfd_select_poll_kevent_block_helper,
514 				   &ctx) == 0);
515 
516 	/*
517 	 * Wait for the helper to block in poll().  Give it some time
518 	 * so that if the poll returns immediately, we'll notice.
519 	 */
520 	set_state(&ctx, 666);
521 	ATF_REQUIRE(wait_barrier(&ctx));
522 	sleep(2);
523 	ATF_REQUIRE(get_state(&ctx) == 666);
524 
525 	/*
526 	 * Write the max value to the eventfd so that it becomes readable
527 	 * and unblocks the helper waiting in poll().
528 	 */
529 	ATF_REQUIRE(eventfd_write(ctx.efd, UINT64_MAX - 1) == 0);
530 
531 	/*
532 	 * Ensure the helper woke from the poll() call.
533 	 */
534 	ATF_REQUIRE(wait_barrier(&ctx));
535 	ATF_REQUIRE(get_state(&ctx) == 0);
536 
537 	/*
538 	 * Wait for the helper to block in poll(), this time waiting
539 	 * for writability.
540 	 */
541 	set_state(&ctx, 666);
542 	ATF_REQUIRE(wait_barrier(&ctx));
543 	sleep(2);
544 	ATF_REQUIRE(get_state(&ctx) == 666);
545 
546 	/*
547 	 * Now read the value, which will reset the eventfd to 0 and
548 	 * unblock the poll() call.
549 	 */
550 	ATF_REQUIRE(eventfd_read(ctx.efd, &efd_value) == 0);
551 	ATF_REQUIRE(efd_value == UINT64_MAX - 1);
552 
553 	/*
554 	 * Ensure that the helper woke from the poll() call.
555 	 */
556 	ATF_REQUIRE(wait_barrier(&ctx));
557 	ATF_REQUIRE(get_state(&ctx) == 0);
558 
559 	/*
560 	 * Wait for the helper to block in select(), waiting for readability.
561 	 */
562 	set_state(&ctx, 666);
563 	ATF_REQUIRE(wait_barrier(&ctx));
564 	sleep(2);
565 	ATF_REQUIRE(get_state(&ctx) == 666);
566 
567 	/*
568 	 * Write the max value to the eventfd so that it becomes readable
569 	 * and unblocks the helper waiting in select().
570 	 */
571 	efd_value = UINT64_MAX - 1;
572 	ATF_REQUIRE(eventfd_write(ctx.efd, UINT64_MAX - 1) == 0);
573 
574 	/*
575 	 * Ensure the helper woke from the select() call.
576 	 */
577 	ATF_REQUIRE(wait_barrier(&ctx));
578 	ATF_REQUIRE(get_state(&ctx) == 0);
579 
580 	/*
581 	 * Wait for the helper to block in select(), this time waiting
582 	 * for writability.
583 	 */
584 	set_state(&ctx, 666);
585 	ATF_REQUIRE(wait_barrier(&ctx));
586 	sleep(2);
587 	ATF_REQUIRE(get_state(&ctx) == 666);
588 
589 	/*
590 	 * Now read the value, which will reset the eventfd to 0 and
591 	 * unblock the select() call.
592 	 */
593 	ATF_REQUIRE(eventfd_read(ctx.efd, &efd_value) == 0);
594 	ATF_REQUIRE(efd_value == UINT64_MAX - 1);
595 
596 	/*
597 	 * Ensure that the helper woke from the select() call.
598 	 */
599 	ATF_REQUIRE(wait_barrier(&ctx));
600 	ATF_REQUIRE(get_state(&ctx) == 0);
601 
602 	/*
603 	 * Wait for the helper to block in kevent(), waiting for readability.
604 	 */
605 	set_state(&ctx, 666);
606 	ATF_REQUIRE(wait_barrier(&ctx));
607 	sleep(2);
608 	ATF_REQUIRE(get_state(&ctx) == 666);
609 
610 	/*
611 	 * Write the max value to the eventfd so that it becomes readable
612 	 * and unblocks the helper waiting in kevent().
613 	 */
614 	efd_value = UINT64_MAX - 1;
615 	ATF_REQUIRE(eventfd_write(ctx.efd, UINT64_MAX - 1) == 0);
616 
617 	/*
618 	 * Ensure the helper woke from the kevent() call.
619 	 */
620 	ATF_REQUIRE(wait_barrier(&ctx));
621 	ATF_REQUIRE(get_state(&ctx) == 0);
622 
623 	/*
624 	 * Wait for the helper to block in kevent(), this time waiting
625 	 * for writability.
626 	 */
627 	set_state(&ctx, 666);
628 	ATF_REQUIRE(wait_barrier(&ctx));
629 	sleep(2);
630 	ATF_REQUIRE(get_state(&ctx) == 666);
631 
632 	/*
633 	 * Now read the value, which will reset the eventfd to 0 and
634 	 * unblock the select() call.
635 	 */
636 	ATF_REQUIRE(eventfd_read(ctx.efd, &efd_value) == 0);
637 	ATF_REQUIRE(efd_value == UINT64_MAX - 1);
638 
639 	/*
640 	 * Ensure that the helper woke from the kevent() call.
641 	 */
642 	ATF_REQUIRE(wait_barrier(&ctx));
643 	ATF_REQUIRE(get_state(&ctx) == 0);
644 
645 	/* Reap the helper. */
646 	ATF_REQUIRE(pthread_join(helper, &join_val) == 0);
647 
648 	(void) close(ctx.efd);
649 }
650 
651 /*****************************************************************************/
652 
653 static void *
eventfd_restart_helper(void * const v)654 eventfd_restart_helper(void * const v)
655 {
656 	struct helper_context * const ctx = v;
657 	eventfd_t efd_value;
658 
659 	/*
660 	 * Issue a single read to ensure that the descriptor is valid.
661 	 * Thius will not block because it was created with an initial
662 	 * count of 1.
663 	 */
664 	ATF_REQUIRE(eventfd_read(ctx->efd, &efd_value) == 0);
665 	ATF_REQUIRE(efd_value == 1);
666 
667 	ATF_REQUIRE(wait_barrier(ctx));
668 
669 	/*
670 	 * Block in read.  The main thread will close the descriptor,
671 	 * which should unblock us and result in EBADF.
672 	 */
673 	ATF_REQUIRE(get_state(ctx) == 666);
674 	ATF_REQUIRE_ERRNO(EBADF, eventfd_read(ctx->efd, &efd_value) == -1);
675 	set_state(ctx, 0);
676 
677 	ATF_REQUIRE(wait_barrier(ctx));
678 
679 	return NULL;
680 }
681 
682 ATF_TC(eventfd_restart);
ATF_TC_HEAD(eventfd_restart,tc)683 ATF_TC_HEAD(eventfd_restart, tc)
684 {
685 	atf_tc_set_md_var(tc, "descr",
686 	    "exercises the 'restart' fileop code path");
687 }
ATF_TC_BODY(eventfd_restart,tc)688 ATF_TC_BODY(eventfd_restart, tc)
689 {
690 	struct helper_context ctx;
691 	pthread_t helper;
692 	void *join_val;
693 
694 	init_helper_context(&ctx);
695 
696 	ATF_REQUIRE((ctx.efd = eventfd(1, 0)) >= 0);
697 
698 	ATF_REQUIRE(pthread_create(&helper, NULL,
699 				   eventfd_restart_helper, &ctx) == 0);
700 
701 	/*
702 	 * Wait for the helper to block in read().  Give it some time
703 	 * so that if the poll returns immediately, we'll notice.
704 	 */
705 	set_state(&ctx, 666);
706 	ATF_REQUIRE(wait_barrier(&ctx));
707 	sleep(2);
708 	ATF_REQUIRE(get_state(&ctx) == 666);
709 
710 	/*
711 	 * Close the descriptor.  This should unblock the reader,
712 	 * and cause it to receive EBADF.
713 	 */
714 	ATF_REQUIRE(close(ctx.efd) == 0);
715 
716 	/*
717 	 * Ensure that the helper woke from the read() call.
718 	 */
719 	ATF_REQUIRE(wait_barrier(&ctx));
720 	ATF_REQUIRE(get_state(&ctx) == 0);
721 
722 	/* Reap the helper. */
723 	ATF_REQUIRE(pthread_join(helper, &join_val) == 0);
724 }
725 
726 /*****************************************************************************/
727 
728 ATF_TC(eventfd_badflags);
ATF_TC_HEAD(eventfd_badflags,tc)729 ATF_TC_HEAD(eventfd_badflags, tc)
730 {
731 	atf_tc_set_md_var(tc, "descr",
732 	    "validates behavior when eventfd() called with bad flags");
733 }
ATF_TC_BODY(eventfd_badflags,tc)734 ATF_TC_BODY(eventfd_badflags, tc)
735 {
736 	ATF_REQUIRE_ERRNO(EINVAL,
737 	    eventfd(0, ~(EFD_SEMAPHORE | EFD_CLOEXEC | EFD_NONBLOCK)) == -1);
738 }
739 
740 /*****************************************************************************/
741 
742 ATF_TC(eventfd_bufsize);
ATF_TC_HEAD(eventfd_bufsize,tc)743 ATF_TC_HEAD(eventfd_bufsize, tc)
744 {
745 	atf_tc_set_md_var(tc, "descr",
746 	    "validates expected buffer size behavior");
747 }
ATF_TC_BODY(eventfd_bufsize,tc)748 ATF_TC_BODY(eventfd_bufsize, tc)
749 {
750 	eventfd_t efd_value[2];
751 	int efd;
752 
753 	ATF_REQUIRE((efd = eventfd(1, EFD_NONBLOCK)) >= 0);
754 
755 	ATF_REQUIRE_ERRNO(EINVAL,
756 	    read(efd, efd_value, sizeof(efd_value[0]) - 1) == -1);
757 
758 	efd_value[0] = 0xdeadbeef;
759 	efd_value[1] = 0xdeadbeef;
760 	ATF_REQUIRE(read(efd, efd_value, sizeof(efd_value)) ==
761 	    sizeof(efd_value[0]));
762 	ATF_REQUIRE(efd_value[0] == 1);
763 	ATF_REQUIRE(efd_value[1] == 0xdeadbeef);
764 
765 	ATF_REQUIRE_ERRNO(EINVAL,
766 	    write(efd, efd_value, sizeof(efd_value[0]) - 1) == -1);
767 	ATF_REQUIRE(write(efd, efd_value, sizeof(efd_value)) ==
768 	    sizeof(efd_value[0]));
769 
770 	ATF_REQUIRE(read(efd, efd_value, sizeof(efd_value)) ==
771 	    sizeof(efd_value[0]));
772 	ATF_REQUIRE(efd_value[0] == 1);
773 	ATF_REQUIRE(efd_value[1] == 0xdeadbeef);
774 
775 	(void) close(efd);
776 }
777 
778 /*****************************************************************************/
779 
780 ATF_TC(eventfd_fcntl);
ATF_TC_HEAD(eventfd_fcntl,tc)781 ATF_TC_HEAD(eventfd_fcntl, tc)
782 {
783 	atf_tc_set_md_var(tc, "descr",
784 	    "validates fcntl behavior");
785 }
ATF_TC_BODY(eventfd_fcntl,tc)786 ATF_TC_BODY(eventfd_fcntl, tc)
787 {
788 	int efd;
789 	int val;
790 
791 	ATF_REQUIRE((efd = eventfd(1, 0)) >= 0);
792 	ATF_REQUIRE((fcntl(efd, F_GETFL) & O_NONBLOCK) == 0);
793 	ATF_REQUIRE(fcntl(efd, F_SETFL, O_NONBLOCK) == 0);
794 	ATF_REQUIRE((fcntl(efd, F_GETFL) & O_NONBLOCK) != 0);
795 	ATF_REQUIRE((fcntl(efd, F_GETFD) & FD_CLOEXEC) == 0);
796 
797 	ATF_REQUIRE(ioctl(efd, FIONREAD, &val) == 0);
798 	ATF_REQUIRE(val == sizeof(eventfd_t));
799 
800 	ATF_REQUIRE(ioctl(efd, FIONWRITE, &val) == 0);
801 	ATF_REQUIRE(val == 0);
802 
803 	ATF_REQUIRE_ERRNO(ENOTTY, ioctl(efd, FIONSPACE, &val) == -1);
804 	(void)close(efd);
805 
806 	ATF_REQUIRE((efd = eventfd(1, EFD_NONBLOCK | EFD_CLOEXEC)) >= 0);
807 	ATF_REQUIRE((fcntl(efd, F_GETFL) & ~O_ACCMODE) == O_NONBLOCK);
808 	ATF_REQUIRE((fcntl(efd, F_GETFD) & FD_CLOEXEC) != 0);
809 	ATF_REQUIRE(fcntl(efd, F_SETFD, 0) == 0);
810 	ATF_REQUIRE((fcntl(efd, F_GETFD) & FD_CLOEXEC) == 0);
811 	ATF_REQUIRE(fcntl(efd, F_SETFD, FD_CLOEXEC) == 0);
812 	ATF_REQUIRE((fcntl(efd, F_GETFD) & FD_CLOEXEC) != 0);
813 	(void)close(efd);
814 }
815 
816 /*****************************************************************************/
817 
ATF_TP_ADD_TCS(tp)818 ATF_TP_ADD_TCS(tp)
819 {
820 	ATF_TP_ADD_TC(tp, eventfd_normal);
821 	ATF_TP_ADD_TC(tp, eventfd_semaphore);
822 	ATF_TP_ADD_TC(tp, eventfd_badflags);
823 	ATF_TP_ADD_TC(tp, eventfd_bufsize);
824 	ATF_TP_ADD_TC(tp, eventfd_select_poll_kevent_immed);
825 	ATF_TP_ADD_TC(tp, eventfd_select_poll_kevent_block);
826 	ATF_TP_ADD_TC(tp, eventfd_restart);
827 	ATF_TP_ADD_TC(tp, eventfd_fcntl);
828 
829 	return atf_no_error();
830 }
831