t_sleep.c revision 1.8.6.1 1 /* $NetBSD: t_sleep.c,v 1.8.6.1 2017/03/20 06:57:58 pgoyette 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 <sys/cdefs.h>
30 #include <sys/event.h>
31 #include <sys/signal.h>
32 #include <sys/time.h> /* for TIMESPEC_TO_TIMEVAL on FreeBSD */
33
34 #include <atf-c.h>
35 #include <errno.h>
36 #include <inttypes.h>
37 #include <poll.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <time.h>
42 #include <unistd.h>
43
44 #include "isqemu.h"
45
46 #define BILLION 1000000000LL /* nano-seconds per second */
47 #define MILLION 1000000LL /* nano-seconds per milli-second */
48
49 #define ALARM 6 /* SIGALRM after this many seconds */
50 #define MAXSLEEP 22 /* Maximum delay in seconds */
51 #define KEVNT_TIMEOUT 10300 /* measured in milli-seconds */
52 #define FUZZ (40 * MILLION) /* scheduling fuzz accepted - 40 ms */
53
54 /*
55 * Timer notes
56 *
57 * Most tests use FUZZ as their initial delay value, but 'sleep'
58 * starts at 1sec (since it cannot handle sub-second intervals).
59 * Subsequent passes double the previous interval, up to MAXSLEEP.
60 *
61 * The current values result in 5 passes for the 'sleep' test (at 1,
62 * 2, 4, 8, and 16 seconds) and 10 passes for the other tests (at
63 * 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56, 5.12, 10.24, and 20.48
64 * seconds).
65 *
66 * The ALARM is only set if the current pass's delay is longer, and
67 * only if the ALARM has not already been triggered.
68 *
69 * The 'kevent' test needs the ALARM to be set on a different pass
70 * from when the KEVNT_TIMEOUT fires. So set ALARM to fire on the
71 * penultimate pass, and the KEVNT_TIMEOUT on the final pass. We
72 * set KEVNT_TIMEOUT just barely long enough to put it into the
73 * last test pass, and set MAXSLEEP a couple seconds longer than
74 * necessary, in order to avoid a QEMU bug which nearly doubles
75 * some timers.
76 */
77
78 static volatile int sig;
79
80 int sleeptest(int (*)(struct timespec *, struct timespec *), bool, bool);
81 int do_nanosleep(struct timespec *, struct timespec *);
82 int do_select(struct timespec *, struct timespec *);
83 int do_poll(struct timespec *, struct timespec *);
84 int do_sleep(struct timespec *, struct timespec *);
85 int do_kevent(struct timespec *, struct timespec *);
86 void sigalrm(int);
87
88 void
89 sigalrm(int s)
90 {
91
92 sig++;
93 }
94
95 int
96 do_nanosleep(struct timespec *delay, struct timespec *remain)
97 {
98 int ret;
99
100 if (nanosleep(delay, remain) == -1)
101 ret = (errno == EINTR ? 0 : errno);
102 else
103 ret = 0;
104 return ret;
105 }
106
107 int
108 do_select(struct timespec *delay, struct timespec *remain)
109 {
110 int ret;
111 struct timeval tv;
112
113 TIMESPEC_TO_TIMEVAL(&tv, delay);
114 if (select(0, NULL, NULL, NULL, &tv) == -1)
115 ret = (errno == EINTR ? 0 : errno);
116 else
117 ret = 0;
118 return ret;
119 }
120
121 int
122 do_poll(struct timespec *delay, struct timespec *remain)
123 {
124 int ret;
125 struct timeval tv;
126
127 TIMESPEC_TO_TIMEVAL(&tv, delay);
128 if (pollts(NULL, 0, delay, NULL) == -1)
129 ret = (errno == EINTR ? 0 : errno);
130 else
131 ret = 0;
132 return ret;
133 }
134
135 int
136 do_sleep(struct timespec *delay, struct timespec *remain)
137 {
138 struct timeval tv;
139
140 TIMESPEC_TO_TIMEVAL(&tv, delay);
141 remain->tv_sec = sleep(delay->tv_sec);
142 remain->tv_nsec = 0;
143
144 return 0;
145 }
146
147 int
148 do_kevent(struct timespec *delay, struct timespec *remain)
149 {
150 struct kevent ktimer;
151 struct kevent kresult;
152 int rtc, kq, kerrno;
153 int tmo;
154
155 ATF_REQUIRE_MSG((kq = kqueue()) != -1, "kqueue: %s", strerror(errno));
156
157 tmo = KEVNT_TIMEOUT;
158
159 /*
160 * If we expect the KEVNT_TIMEOUT to fire, and we're running
161 * under QEMU, make sure the delay is long enough to account
162 * for the effects of PR kern/43997 !
163 */
164 if (isQEMU() &&
165 tmo/1000 < delay->tv_sec && tmo/500 > delay->tv_sec)
166 delay->tv_sec = MAXSLEEP;
167
168 EV_SET(&ktimer, 1, EVFILT_TIMER, EV_ADD, 0, tmo, 0);
169
170 rtc = kevent(kq, &ktimer, 1, &kresult, 1, delay);
171 kerrno = errno;
172
173 (void)close(kq);
174
175 if (rtc == -1) {
176 ATF_REQUIRE_MSG(kerrno == EINTR, "kevent: %s", strerror(errno));
177 return 0;
178 }
179
180 if (delay->tv_sec * BILLION + delay->tv_nsec > tmo * MILLION)
181 ATF_REQUIRE_MSG(rtc > 0,
182 "kevent: KEVNT_TIMEOUT did not cause EVFILT_TIMER event");
183
184 return 0;
185 }
186
187 ATF_TC(nanosleep);
188 ATF_TC_HEAD(nanosleep, tc)
189 {
190
191 atf_tc_set_md_var(tc, "descr", "Test nanosleep(2) timing");
192 atf_tc_set_md_var(tc, "timeout", "65");
193 }
194
195 ATF_TC_BODY(nanosleep, tc)
196 {
197
198 sleeptest(do_nanosleep, true, false);
199 }
200
201 ATF_TC(select);
202 ATF_TC_HEAD(select, tc)
203 {
204
205 atf_tc_set_md_var(tc, "descr", "Test select(2) timing");
206 atf_tc_set_md_var(tc, "timeout", "65");
207 }
208
209 ATF_TC_BODY(select, tc)
210 {
211
212 sleeptest(do_select, true, true);
213 }
214
215 ATF_TC(poll);
216 ATF_TC_HEAD(poll, tc)
217 {
218
219 atf_tc_set_md_var(tc, "descr", "Test poll(2) timing");
220 atf_tc_set_md_var(tc, "timeout", "65");
221 }
222
223 ATF_TC_BODY(poll, tc)
224 {
225
226 sleeptest(do_poll, true, true);
227 }
228
229 ATF_TC(sleep);
230 ATF_TC_HEAD(sleep, tc)
231 {
232
233 atf_tc_set_md_var(tc, "descr", "Test sleep(3) timing");
234 atf_tc_set_md_var(tc, "timeout", "65");
235 }
236
237 ATF_TC_BODY(sleep, tc)
238 {
239
240 sleeptest(do_sleep, false, false);
241 }
242
243 ATF_TC(kevent);
244 ATF_TC_HEAD(kevent, tc)
245 {
246
247 atf_tc_set_md_var(tc, "descr", "Test kevent(2) timing");
248 atf_tc_set_md_var(tc, "timeout", "65");
249 }
250
251 ATF_TC_BODY(kevent, tc)
252 {
253
254 sleeptest(do_kevent, true, true);
255 }
256
257 int
258 sleeptest(int (*test)(struct timespec *, struct timespec *),
259 bool subsec, bool sim_remain)
260 {
261 struct timespec tsa, tsb, tslp, tremain;
262 int64_t delta1, delta2, delta3, round;
263
264 sig = 0;
265 signal(SIGALRM, sigalrm);
266
267 if (subsec) {
268 round = 1;
269 delta3 = FUZZ;
270 } else {
271 round = 1000000000;
272 delta3 = round;
273 }
274
275 tslp.tv_sec = delta3 / 1000000000;
276 tslp.tv_nsec = delta3 % 1000000000;
277
278 while (tslp.tv_sec <= MAXSLEEP) {
279 /*
280 * disturb sleep by signal on purpose
281 */
282 if (tslp.tv_sec > ALARM && sig == 0)
283 alarm(ALARM);
284
285 clock_gettime(CLOCK_REALTIME, &tsa);
286 (*test)(&tslp, &tremain);
287 clock_gettime(CLOCK_REALTIME, &tsb);
288
289 if (sim_remain) {
290 timespecsub(&tsb, &tsa, &tremain);
291 timespecsub(&tslp, &tremain, &tremain);
292 }
293
294 delta1 = (int64_t)tsb.tv_sec - (int64_t)tsa.tv_sec;
295 delta1 *= BILLION;
296 delta1 += (int64_t)tsb.tv_nsec - (int64_t)tsa.tv_nsec;
297
298 delta2 = (int64_t)tremain.tv_sec * BILLION;
299 delta2 += (int64_t)tremain.tv_nsec;
300
301 delta3 = (int64_t)tslp.tv_sec * BILLION;
302 delta3 += (int64_t)tslp.tv_nsec - delta1 - delta2;
303
304 delta3 /= round;
305 delta3 *= round;
306
307 if (delta3 > FUZZ || delta3 < -FUZZ) {
308 if (!sim_remain)
309 atf_tc_expect_fail("Long reschedule latency "
310 "due to PR kern/43997");
311
312 atf_tc_fail("Reschedule latency %"PRId64" exceeds "
313 "allowable fuzz %lld", delta3, FUZZ);
314 }
315 delta3 = (int64_t)tslp.tv_sec * 2 * BILLION;
316 delta3 += (int64_t)tslp.tv_nsec * 2;
317
318 delta3 /= round;
319 delta3 *= round;
320 if (delta3 < FUZZ)
321 break;
322 tslp.tv_sec = delta3 / BILLION;
323 tslp.tv_nsec = delta3 % BILLION;
324 }
325 ATF_REQUIRE_MSG(sig == 1, "Alarm did not fire!");
326
327 atf_tc_pass();
328 }
329
330 ATF_TP_ADD_TCS(tp)
331 {
332 ATF_TP_ADD_TC(tp, nanosleep);
333 ATF_TP_ADD_TC(tp, select);
334 ATF_TP_ADD_TC(tp, poll);
335 ATF_TP_ADD_TC(tp, sleep);
336 ATF_TP_ADD_TC(tp, kevent);
337
338 return atf_no_error();
339 }
340