t_sleep.c revision 313498 
1/* $NetBSD: t_sleep.c,v 1.9 2016/08/11 21:34:11 kre Exp $ */
2
3/*-
4 * Copyright (c) 2006 Frank Kardel
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 <atf-c.h>
30#include <errno.h>
31#include <poll.h>
32#include <stdio.h>
33#include <stdlib.h>
34#include <string.h>
35#include <time.h>
36#include <unistd.h>
37
38#include <sys/cdefs.h>
39#include <sys/event.h>
40#include <sys/signal.h>
41
42#include "isqemu.h"
43
44#define BILLION		1000000000LL	/* nano-seconds per second */
45#define MILLION		1000000LL	/* nano-seconds per milli-second */
46
47#define ALARM		6		/* SIGALRM after this many seconds */
48#define MAXSLEEP	22		/* Maximum delay in seconds */
49#define KEVNT_TIMEOUT	10300		/* measured in milli-seconds */
50#define FUZZ		(40 * MILLION)	/* scheduling fuzz accepted - 40 ms */
51
52#ifdef __FreeBSD__
53#include <sys/time.h>
54#include <inttypes.h>
55#endif
56
57/*
58 * Timer notes
59 *
60 * Most tests use FUZZ as their initial delay value, but 'sleep'
61 * starts at 1sec (since it cannot handle sub-second intervals).
62 * Subsequent passes double the previous interval, up to MAXSLEEP.
63 *
64 * The current values result in 5 passes for the 'sleep' test (at 1,
65 * 2, 4, 8, and 16 seconds) and 10 passes for the other tests (at
66 * 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56, 5.12, 10.24, and 20.48
67 * seconds).
68 *
69 * The ALARM is only set if the current pass's delay is longer, and
70 * only if the ALARM has not already been triggered.
71 *
72 * The 'kevent' test needs the ALARM to be set on a different pass
73 * from when the KEVNT_TIMEOUT fires.  So set ALARM to fire on the
74 * penultimate pass, and the KEVNT_TIMEOUT on the final pass.  We
75 * set KEVNT_TIMEOUT just barely long enough to put it into the
76 * last test pass, and set MAXSLEEP a couple seconds longer than
77 * necessary, in order to avoid a QEMU bug which nearly doubles
78 * some timers.
79 */
80
81static volatile int sig;
82
83int sleeptest(int (*)(struct timespec *, struct timespec *), bool, bool);
84int do_nanosleep(struct timespec *, struct timespec *);
85int do_select(struct timespec *, struct timespec *);
86#ifdef __NetBSD__
87int do_poll(struct timespec *, struct timespec *);
88#endif
89int do_sleep(struct timespec *, struct timespec *);
90int do_kevent(struct timespec *, struct timespec *);
91void sigalrm(int);
92
93void
94sigalrm(int s)
95{
96
97	sig++;
98}
99
100int
101do_nanosleep(struct timespec *delay, struct timespec *remain)
102{
103	int ret;
104
105	if (nanosleep(delay, remain) == -1)
106		ret = (errno == EINTR ? 0 : errno);
107	else
108		ret = 0;
109	return ret;
110}
111
112int
113do_select(struct timespec *delay, struct timespec *remain)
114{
115	int ret;
116	struct timeval tv;
117
118	TIMESPEC_TO_TIMEVAL(&tv, delay);
119	if (select(0, NULL, NULL, NULL, &tv) == -1)
120		ret = (errno == EINTR ? 0 : errno);
121	else
122		ret = 0;
123	return ret;
124}
125
126#ifdef __NetBSD__
127int
128do_poll(struct timespec *delay, struct timespec *remain)
129{
130	int ret;
131	struct timeval tv;
132
133	TIMESPEC_TO_TIMEVAL(&tv, delay);
134	if (pollts(NULL, 0, delay, NULL) == -1)
135		ret = (errno == EINTR ? 0 : errno);
136	else
137		ret = 0;
138	return ret;
139}
140#endif
141
142int
143do_sleep(struct timespec *delay, struct timespec *remain)
144{
145	struct timeval tv;
146
147	TIMESPEC_TO_TIMEVAL(&tv, delay);
148	remain->tv_sec = sleep(delay->tv_sec);
149	remain->tv_nsec = 0;
150
151	return 0;
152}
153
154int
155do_kevent(struct timespec *delay, struct timespec *remain)
156{
157	struct kevent ktimer;
158	struct kevent kresult;
159	int rtc, kq, kerrno;
160	int tmo;
161
162	ATF_REQUIRE_MSG((kq = kqueue()) != -1, "kqueue: %s", strerror(errno));
163
164	tmo = KEVNT_TIMEOUT;
165
166	/*
167	 * If we expect the KEVNT_TIMEOUT to fire, and we're running
168	 * under QEMU, make sure the delay is long enough to account
169	 * for the effects of PR kern/43997 !
170	 */
171	if (isQEMU() &&
172	    tmo/1000 < delay->tv_sec && tmo/500 > delay->tv_sec)
173		delay->tv_sec = MAXSLEEP;
174
175	EV_SET(&ktimer, 1, EVFILT_TIMER, EV_ADD, 0, tmo, 0);
176
177	rtc = kevent(kq, &ktimer, 1, &kresult, 1, delay);
178	kerrno = errno;
179
180	(void)close(kq);
181
182	if (rtc == -1) {
183		ATF_REQUIRE_MSG(kerrno == EINTR, "kevent: %s",
184		    strerror(kerrno));
185		return 0;
186	}
187
188	if (delay->tv_sec * BILLION + delay->tv_nsec > tmo * MILLION)
189		ATF_REQUIRE_MSG(rtc > 0,
190		    "kevent: KEVNT_TIMEOUT did not cause EVFILT_TIMER event");
191
192	return 0;
193}
194
195ATF_TC(nanosleep);
196ATF_TC_HEAD(nanosleep, tc)
197{
198
199	atf_tc_set_md_var(tc, "descr", "Test nanosleep(2) timing");
200	atf_tc_set_md_var(tc, "timeout", "65");
201}
202
203ATF_TC_BODY(nanosleep, tc)
204{
205
206	sleeptest(do_nanosleep, true, false);
207}
208
209ATF_TC(select);
210ATF_TC_HEAD(select, tc)
211{
212
213	atf_tc_set_md_var(tc, "descr", "Test select(2) timing");
214	atf_tc_set_md_var(tc, "timeout", "65");
215}
216
217ATF_TC_BODY(select, tc)
218{
219
220	sleeptest(do_select, true, true);
221}
222
223#ifdef __NetBSD__
224ATF_TC(poll);
225ATF_TC_HEAD(poll, tc)
226{
227
228	atf_tc_set_md_var(tc, "descr", "Test poll(2) timing");
229	atf_tc_set_md_var(tc, "timeout", "65");
230}
231
232ATF_TC_BODY(poll, tc)
233{
234
235	sleeptest(do_poll, true, true);
236}
237#endif
238
239ATF_TC(sleep);
240ATF_TC_HEAD(sleep, tc)
241{
242
243	atf_tc_set_md_var(tc, "descr", "Test sleep(3) timing");
244	atf_tc_set_md_var(tc, "timeout", "65");
245}
246
247ATF_TC_BODY(sleep, tc)
248{
249
250	sleeptest(do_sleep, false, false);
251}
252
253ATF_TC(kevent);
254ATF_TC_HEAD(kevent, tc)
255{
256
257	atf_tc_set_md_var(tc, "descr", "Test kevent(2) timing");
258	atf_tc_set_md_var(tc, "timeout", "65");
259}
260
261ATF_TC_BODY(kevent, tc)
262{
263
264	sleeptest(do_kevent, true, true);
265}
266
267int
268sleeptest(int (*test)(struct timespec *, struct timespec *),
269	   bool subsec, bool sim_remain)
270{
271	struct timespec tsa, tsb, tslp, tremain;
272	int64_t delta1, delta2, delta3, round;
273
274	sig = 0;
275	signal(SIGALRM, sigalrm);
276
277	if (subsec) {
278		round = 1;
279		delta3 = FUZZ;
280	} else {
281		round = 1000000000;
282		delta3 = round;
283	}
284
285	tslp.tv_sec = delta3 / 1000000000;
286	tslp.tv_nsec = delta3 % 1000000000;
287
288	while (tslp.tv_sec <= MAXSLEEP) {
289		/*
290		 * disturb sleep by signal on purpose
291		 */
292		if (tslp.tv_sec > ALARM && sig == 0)
293			alarm(ALARM);
294
295		clock_gettime(CLOCK_REALTIME, &tsa);
296		(*test)(&tslp, &tremain);
297		clock_gettime(CLOCK_REALTIME, &tsb);
298
299		if (sim_remain) {
300			timespecsub(&tsb, &tsa, &tremain);
301			timespecsub(&tslp, &tremain, &tremain);
302		}
303
304		delta1 = (int64_t)tsb.tv_sec - (int64_t)tsa.tv_sec;
305		delta1 *= BILLION;
306		delta1 += (int64_t)tsb.tv_nsec - (int64_t)tsa.tv_nsec;
307
308		delta2 = (int64_t)tremain.tv_sec * BILLION;
309		delta2 += (int64_t)tremain.tv_nsec;
310
311		delta3 = (int64_t)tslp.tv_sec * BILLION;
312		delta3 += (int64_t)tslp.tv_nsec - delta1 - delta2;
313
314		delta3 /= round;
315		delta3 *= round;
316
317		if (delta3 > FUZZ || delta3 < -FUZZ) {
318			if (!sim_remain)
319				atf_tc_expect_fail("Long reschedule latency "
320				    "due to PR kern/43997");
321
322			atf_tc_fail("Reschedule latency %"PRId64" exceeds "
323			    "allowable fuzz %lld", delta3, FUZZ);
324		}
325		delta3 = (int64_t)tslp.tv_sec * 2 * BILLION;
326		delta3 += (int64_t)tslp.tv_nsec * 2;
327
328		delta3 /= round;
329		delta3 *= round;
330		if (delta3 < FUZZ)
331			break;
332		tslp.tv_sec = delta3 / BILLION;
333		tslp.tv_nsec = delta3 % BILLION;
334	}
335	ATF_REQUIRE_MSG(sig == 1, "Alarm did not fire!");
336
337	atf_tc_pass();
338}
339
340ATF_TP_ADD_TCS(tp)
341{
342	ATF_TP_ADD_TC(tp, nanosleep);
343	ATF_TP_ADD_TC(tp, select);
344#ifdef __NetBSD__
345	ATF_TP_ADD_TC(tp, poll);
346#endif
347	ATF_TP_ADD_TC(tp, sleep);
348	ATF_TP_ADD_TC(tp, kevent);
349
350	return atf_no_error();
351}
352