t_sleep.c revision 272458 
1/* $NetBSD: t_sleep.c,v 1.8 2014/07/15 14:56:34 gson 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/*
53 * Timer notes
54 *
55 * Most tests use FUZZ as their initial delay value, but 'sleep'
56 * starts at 1sec (since it cannot handle sub-second intervals).
57 * Subsequent passes double the previous interval, up to MAXSLEEP.
58 *
59 * The current values result in 5 passes for the 'sleep' test (at 1,
60 * 2, 4, 8, and 16 seconds) and 10 passes for the other tests (at
61 * 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56, 5.12, 10.24, and 20.48
62 * seconds).
63 *
64 * The ALARM is only set if the current pass's delay is longer, and
65 * only if the ALARM has not already been triggered.
66 *
67 * The 'kevent' test needs the ALARM to be set on a different pass
68 * from when the KEVNT_TIMEOUT fires.  So set ALARM to fire on the
69 * penultimate pass, and the KEVNT_TIMEOUT on the final pass.  We
70 * set KEVNT_TIMEOUT just barely long enough to put it into the
71 * last test pass, and set MAXSLEEP a couple seconds longer than
72 * necessary, in order to avoid a QEMU bug which nearly doubles
73 * some timers.
74 */
75
76static volatile int sig;
77
78int sleeptest(int (*)(struct timespec *, struct timespec *), bool, bool);
79int do_nanosleep(struct timespec *, struct timespec *);
80int do_select(struct timespec *, struct timespec *);
81int do_poll(struct timespec *, struct timespec *);
82int do_sleep(struct timespec *, struct timespec *);
83int do_kevent(struct timespec *, struct timespec *);
84void sigalrm(int);
85
86void
87sigalrm(int s)
88{
89
90	sig++;
91}
92
93int
94do_nanosleep(struct timespec *delay, struct timespec *remain)
95{
96	int ret;
97
98	if (nanosleep(delay, remain) == -1)
99		ret = (errno == EINTR ? 0 : errno);
100	else
101		ret = 0;
102	return ret;
103}
104
105int
106do_select(struct timespec *delay, struct timespec *remain)
107{
108	int ret;
109	struct timeval tv;
110
111	TIMESPEC_TO_TIMEVAL(&tv, delay);
112	if (select(0, NULL, NULL, NULL, &tv) == -1)
113		ret = (errno == EINTR ? 0 : errno);
114	else
115		ret = 0;
116	return ret;
117}
118
119int
120do_poll(struct timespec *delay, struct timespec *remain)
121{
122	int ret;
123	struct timeval tv;
124
125	TIMESPEC_TO_TIMEVAL(&tv, delay);
126	if (pollts(NULL, 0, delay, NULL) == -1)
127		ret = (errno == EINTR ? 0 : errno);
128	else
129		ret = 0;
130	return ret;
131}
132
133int
134do_sleep(struct timespec *delay, struct timespec *remain)
135{
136	struct timeval tv;
137
138	TIMESPEC_TO_TIMEVAL(&tv, delay);
139	remain->tv_sec = sleep(delay->tv_sec);
140	remain->tv_nsec = 0;
141
142	return 0;
143}
144
145int
146do_kevent(struct timespec *delay, struct timespec *remain)
147{
148	struct kevent ktimer;
149	struct kevent kresult;
150	int rtc, kq, kerrno;
151	int tmo;
152
153	ATF_REQUIRE_MSG((kq = kqueue()) != -1, "kqueue: %s", strerror(errno));
154
155	tmo = KEVNT_TIMEOUT;
156
157	/*
158	 * If we expect the KEVNT_TIMEOUT to fire, and we're running
159	 * under QEMU, make sure the delay is long enough to account
160	 * for the effects of PR kern/43997 !
161	 */
162	if (isQEMU() &&
163	    tmo/1000 < delay->tv_sec && tmo/500 > delay->tv_sec)
164		delay->tv_sec = MAXSLEEP;
165
166	EV_SET(&ktimer, 1, EVFILT_TIMER, EV_ADD, 0, tmo, 0);
167
168	rtc = kevent(kq, &ktimer, 1, &kresult, 1, delay);
169	kerrno = errno;
170
171	(void)close(kq);
172
173	if (rtc == -1) {
174		ATF_REQUIRE_MSG(kerrno == EINTR, "kevent: %s", strerror(errno));
175		return 0;
176	}
177
178	if (delay->tv_sec * BILLION + delay->tv_nsec > tmo * MILLION)
179		ATF_REQUIRE_MSG(rtc > 0,
180		    "kevent: KEVNT_TIMEOUT did not cause EVFILT_TIMER event");
181
182	return 0;
183}
184
185ATF_TC(nanosleep);
186ATF_TC_HEAD(nanosleep, tc)
187{
188
189	atf_tc_set_md_var(tc, "descr", "Test nanosleep(2) timing");
190	atf_tc_set_md_var(tc, "timeout", "65");
191}
192
193ATF_TC_BODY(nanosleep, tc)
194{
195
196	sleeptest(do_nanosleep, true, false);
197}
198
199ATF_TC(select);
200ATF_TC_HEAD(select, tc)
201{
202
203	atf_tc_set_md_var(tc, "descr", "Test select(2) timing");
204	atf_tc_set_md_var(tc, "timeout", "65");
205}
206
207ATF_TC_BODY(select, tc)
208{
209
210	sleeptest(do_select, true, true);
211}
212
213ATF_TC(poll);
214ATF_TC_HEAD(poll, tc)
215{
216
217	atf_tc_set_md_var(tc, "descr", "Test poll(2) timing");
218	atf_tc_set_md_var(tc, "timeout", "65");
219}
220
221ATF_TC_BODY(poll, tc)
222{
223
224	sleeptest(do_poll, true, true);
225}
226
227ATF_TC(sleep);
228ATF_TC_HEAD(sleep, tc)
229{
230
231	atf_tc_set_md_var(tc, "descr", "Test sleep(3) timing");
232	atf_tc_set_md_var(tc, "timeout", "65");
233}
234
235ATF_TC_BODY(sleep, tc)
236{
237
238	sleeptest(do_sleep, false, false);
239}
240
241ATF_TC(kevent);
242ATF_TC_HEAD(kevent, tc)
243{
244
245	atf_tc_set_md_var(tc, "descr", "Test kevent(2) timing");
246	atf_tc_set_md_var(tc, "timeout", "65");
247}
248
249ATF_TC_BODY(kevent, tc)
250{
251
252	sleeptest(do_kevent, true, true);
253}
254
255int
256sleeptest(int (*test)(struct timespec *, struct timespec *),
257	   bool subsec, bool sim_remain)
258{
259	struct timespec tsa, tsb, tslp, tremain;
260	int64_t delta1, delta2, delta3, round;
261
262	sig = 0;
263	signal(SIGALRM, sigalrm);
264
265	if (subsec) {
266		round = 1;
267		delta3 = FUZZ;
268	} else {
269		round = 1000000000;
270		delta3 = round;
271	}
272
273	tslp.tv_sec = delta3 / 1000000000;
274	tslp.tv_nsec = delta3 % 1000000000;
275
276	while (tslp.tv_sec <= MAXSLEEP) {
277		/*
278		 * disturb sleep by signal on purpose
279		 */
280		if (tslp.tv_sec > ALARM && sig == 0)
281			alarm(ALARM);
282
283		clock_gettime(CLOCK_REALTIME, &tsa);
284		(*test)(&tslp, &tremain);
285		clock_gettime(CLOCK_REALTIME, &tsb);
286
287		if (sim_remain) {
288			timespecsub(&tsb, &tsa, &tremain);
289			timespecsub(&tslp, &tremain, &tremain);
290		}
291
292		delta1 = (int64_t)tsb.tv_sec - (int64_t)tsa.tv_sec;
293		delta1 *= BILLION;
294		delta1 += (int64_t)tsb.tv_nsec - (int64_t)tsa.tv_nsec;
295
296		delta2 = (int64_t)tremain.tv_sec * BILLION;
297		delta2 += (int64_t)tremain.tv_nsec;
298
299		delta3 = (int64_t)tslp.tv_sec * BILLION;
300		delta3 += (int64_t)tslp.tv_nsec - delta1 - delta2;
301
302		delta3 /= round;
303		delta3 *= round;
304
305		if (delta3 > FUZZ || delta3 < -FUZZ) {
306			if (!sim_remain)
307				atf_tc_expect_fail("Long reschedule latency "
308				    "due to PR kern/43997");
309
310			atf_tc_fail("Reschedule latency %"PRId64" exceeds "
311			    "allowable fuzz %lld", delta3, FUZZ);
312		}
313		delta3 = (int64_t)tslp.tv_sec * 2 * BILLION;
314		delta3 += (int64_t)tslp.tv_nsec * 2;
315
316		delta3 /= round;
317		delta3 *= round;
318		if (delta3 < FUZZ)
319			break;
320		tslp.tv_sec = delta3 / BILLION;
321		tslp.tv_nsec = delta3 % BILLION;
322	}
323	ATF_REQUIRE_MSG(sig == 1, "Alarm did not fire!");
324
325	atf_tc_pass();
326}
327
328ATF_TP_ADD_TCS(tp)
329{
330	ATF_TP_ADD_TC(tp, nanosleep);
331	ATF_TP_ADD_TC(tp, select);
332	ATF_TP_ADD_TC(tp, poll);
333	ATF_TP_ADD_TC(tp, sleep);
334	ATF_TP_ADD_TC(tp, kevent);
335
336	return atf_no_error();
337}
338