xref: /openbsd-src/regress/lib/libc/sys/t_clock_gettime.c (revision 4e1ee0786f11cc571bd0be17d38e46f635c719fc)
1 /*	$OpenBSD: t_clock_gettime.c,v 1.2 2021/09/02 12:40:44 mbuhl Exp $	*/
2 /* $NetBSD: t_clock_gettime.c,v 1.3 2017/01/13 21:30:41 christos Exp $ */
3 
4 /*-
5  * Copyright (c) 2008 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Frank Kardel.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*-
34  * Copyright (c) 2006 Frank Kardel
35  * All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  *
46  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
47  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
48  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
49  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
50  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
51  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
52  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
53  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
54  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
55  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
56  * POSSIBILITY OF SUCH DAMAGE.
57  */
58 
59 #include "macros.h"
60 
61 #include <sys/cdefs.h>
62 __COPYRIGHT("@(#) Copyright (c) 2008\
63  The NetBSD Foundation, inc. All rights reserved.");
64 __RCSID("$NetBSD: t_clock_gettime.c,v 1.3 2017/01/13 21:30:41 christos Exp $");
65 
66 #include <sys/param.h>
67 #include <sys/sysctl.h>
68 
69 
70 #include "atf-c.h"
71 #include <errno.h>
72 #include <limits.h>
73 #include <stdio.h>
74 #include <stdint.h>
75 #include <stdlib.h>
76 #include <string.h>
77 #include <time.h>
78 #include <unistd.h>
79 
80 #include "h_macros.h"
81 
82 #define MINPOSDIFF	15000000	/* 15 ms for now */
83 #define TIMEOUT		5
84 
85 #define TC_HARDWARE	"kern.timecounter.hardware"
86 #define TC_CHOICE	"kern.timecounter.choice"
87 
88 static void
89 check_timecounter(void)
90 {
91 	struct timespec tsa, tsb, tsl, res;
92 	long long mindiff = INTMAX_MAX;
93 	time_t endlimit;
94 
95 #define CL(x) \
96 	do { \
97 		if ((x) != -1) \
98 			break; \
99 		atf_tc_fail_nonfatal("%s: %s", #x, strerror(errno)); \
100 		return; \
101 	} while (0)
102 
103 	CL(clock_gettime(CLOCK_REALTIME, &tsa));
104 	tsl = tsa;
105 
106 	CL(time(&endlimit));
107 	endlimit += TIMEOUT + 1;
108 
109 	while ((time_t)tsa.tv_sec < endlimit) {
110 		long long diff;
111 
112 		CL(clock_gettime(CLOCK_REALTIME, &tsb));
113 		diff = 1000000000LL * (tsb.tv_sec - tsa.tv_sec)
114 		    + tsb.tv_nsec - tsa.tv_nsec;
115 
116 		if (diff > 0 && mindiff > diff)
117 			mindiff = diff;
118 
119 		if (diff < 0 || diff > MINPOSDIFF) {
120 			long long elapsed;
121 			(void)printf("%stime TSA: 0x%jx.%08jx, TSB: 0x%jx.%08jx, "
122 			    "diff = %lld nsec, ", (diff < 0) ? "BAD " : "",
123 			    (uintmax_t)tsa.tv_sec, (uintmax_t)tsa.tv_nsec,
124 			    (uintmax_t)tsb.tv_sec, (uintmax_t)tsb.tv_nsec, diff);
125 
126 			elapsed = 1000000000LL * (tsb.tv_sec - tsl.tv_sec)
127 			    + tsb.tv_nsec - tsl.tv_nsec;
128 
129 
130 			(void)printf("%lld nsec\n", elapsed);
131 			tsl = tsb;
132 
133 			ATF_CHECK(diff >= 0);
134 			if (diff < 0)
135 				return;
136 		}
137 
138 		tsa.tv_sec = tsb.tv_sec;
139 		tsa.tv_nsec = tsb.tv_nsec;
140 	}
141 
142 	if (clock_getres(CLOCK_REALTIME, &res) == 0) {
143 		long long r = res.tv_sec * 1000000000 + res.tv_nsec;
144 
145 		(void)printf("Claimed resolution: %lld nsec (%f Hz) or "
146 		    "better\n", r, 1.0 / r * 1e9);
147 		(void)printf("Observed minimum non zero delta: %lld "
148 		    "nsec\n", mindiff);
149 	}
150 
151 #undef CL
152 }
153 
154 ATF_TC(clock_gettime_real);
155 ATF_TC_HEAD(clock_gettime_real, tc)
156 {
157 	atf_tc_set_md_var(tc, "require.user", "root");
158 	atf_tc_set_md_var(tc, "descr",
159 	    "Checks the monotonicity of the CLOCK_REALTIME implementation");
160 	atf_tc_set_md_var(tc, "timeout", "300");
161 }
162 
163 ATF_TC_BODY(clock_gettime_real, tc)
164 {
165 	char name[128], cbuf[512], ctrbuf[10240];
166 	size_t cbufsiz = sizeof(cbuf);
167 	size_t ctrbufsiz = sizeof(ctrbuf);
168 	const char *p;
169 	char *save;
170 	int quality, n;
171 
172 	if (sysctlbyname(TC_HARDWARE, cbuf, &cbufsiz, NULL, 0) != 0) {
173 		(void)printf("\nChecking legacy time implementation "
174 		    "for %d seconds\n", TIMEOUT);
175 		check_timecounter();
176 		return;
177 		/* NOTREACHED */
178 	}
179 	(void)printf("%s = %s\n", TC_HARDWARE, cbuf);
180 	REQUIRE_LIBC(save = strdup(cbuf), NULL);
181 
182 	RL(sysctlbyname(TC_CHOICE, ctrbuf, &ctrbufsiz, NULL, 0));
183 	(void)printf("%s = %s\n", TC_CHOICE, ctrbuf);
184 
185 	for (p = ctrbuf, n = 0; sscanf(p, "%127[^(](q=%d, f=%*u Hz)%*[ ]%n",
186 	    name, &quality, &n) == 2; p += n) {
187 		struct timespec ts;
188 		int ret;
189 
190 		if (quality < 0)
191 			continue;
192 
193 		(void)printf("\nChecking %s for %d seconds\n", name, TIMEOUT);
194 		CHECK_LIBC(ret = sysctlbyname(TC_HARDWARE, NULL, 0,
195 		    name, strlen(name)), -1);
196 		if (ret == -1)
197 			continue;
198 
199 		/* wait a bit to select new counter in clockinterrupt */
200 		ts.tv_sec = 0;
201 		ts.tv_nsec = 100000000;
202 		(void)nanosleep(&ts, NULL);
203 
204 		check_timecounter();
205 	}
206 
207 	RL(sysctlbyname(TC_HARDWARE, NULL, 0, save, strlen(save)));
208 }
209 
210 ATF_TP_ADD_TCS(tp)
211 {
212 
213 	ATF_TP_ADD_TC(tp, clock_gettime_real);
214 
215 	return atf_no_error();
216 }
217