xref: /freebsd/contrib/netbsd-tests/lib/libc/sys/t_clock_gettime.c (revision d93a896ef95946b0bf1219866fcb324b78543444)
1 /* $NetBSD: t_clock_gettime.c,v 1.3 2017/01/13 21:30:41 christos Exp $ */
2 
3 /*-
4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Frank Kardel.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*-
33  * Copyright (c) 2006 Frank Kardel
34  * All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  *
45  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
46  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
47  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
48  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
49  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
50  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
51  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
52  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
53  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
54  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
55  * POSSIBILITY OF SUCH DAMAGE.
56  */
57 
58 #include <sys/cdefs.h>
59 __COPYRIGHT("@(#) Copyright (c) 2008\
60  The NetBSD Foundation, inc. All rights reserved.");
61 __RCSID("$NetBSD: t_clock_gettime.c,v 1.3 2017/01/13 21:30:41 christos Exp $");
62 
63 #include <sys/param.h>
64 #include <sys/sysctl.h>
65 
66 
67 #include <atf-c.h>
68 #include <errno.h>
69 #include <limits.h>
70 #include <stdio.h>
71 #include <stdint.h>
72 #include <stdlib.h>
73 #include <string.h>
74 #include <time.h>
75 #include <unistd.h>
76 
77 #include "h_macros.h"
78 
79 #define MINPOSDIFF	15000000	/* 15 ms for now */
80 #define TIMEOUT		5
81 
82 #define TC_HARDWARE	"kern.timecounter.hardware"
83 #define TC_CHOICE	"kern.timecounter.choice"
84 
85 static void
86 check_timecounter(void)
87 {
88 	struct timespec tsa, tsb, tsl, res;
89 	long long mindiff = INTMAX_MAX;
90 	time_t endlimit;
91 
92 #define CL(x) \
93 	do { \
94 		if ((x) != -1) \
95 			break; \
96 		atf_tc_fail_nonfatal("%s: %s", #x, strerror(errno)); \
97 		return; \
98 	} while (0)
99 
100 	CL(clock_gettime(CLOCK_REALTIME, &tsa));
101 	tsl = tsa;
102 
103 	CL(time(&endlimit));
104 	endlimit += TIMEOUT + 1;
105 
106 	while ((time_t)tsa.tv_sec < endlimit) {
107 		long long diff;
108 
109 		CL(clock_gettime(CLOCK_REALTIME, &tsb));
110 		diff = 1000000000LL * (tsb.tv_sec - tsa.tv_sec)
111 		    + tsb.tv_nsec - tsa.tv_nsec;
112 
113 		if (diff > 0 && mindiff > diff)
114 			mindiff = diff;
115 
116 		if (diff < 0 || diff > MINPOSDIFF) {
117 			long long elapsed;
118 			(void)printf("%stime TSA: 0x%jx.%08jx, TSB: 0x%jx.%08jx, "
119 			    "diff = %lld nsec, ", (diff < 0) ? "BAD " : "",
120 			    (uintmax_t)tsa.tv_sec, (uintmax_t)tsa.tv_nsec,
121 			    (uintmax_t)tsb.tv_sec, (uintmax_t)tsb.tv_nsec, diff);
122 
123 			elapsed = 1000000000LL * (tsb.tv_sec - tsl.tv_sec)
124 			    + tsb.tv_nsec - tsl.tv_nsec;
125 
126 
127 			(void)printf("%lld nsec\n", elapsed);
128 			tsl = tsb;
129 
130 			ATF_CHECK(diff >= 0);
131 			if (diff < 0)
132 				return;
133 		}
134 
135 		tsa.tv_sec = tsb.tv_sec;
136 		tsa.tv_nsec = tsb.tv_nsec;
137 	}
138 
139 	if (clock_getres(CLOCK_REALTIME, &res) == 0) {
140 		long long r = res.tv_sec * 1000000000 + res.tv_nsec;
141 
142 		(void)printf("Claimed resolution: %lld nsec (%f Hz) or "
143 		    "better\n", r, 1.0 / r * 1e9);
144 		(void)printf("Observed minimum non zero delta: %lld "
145 		    "nsec\n", mindiff);
146 	}
147 
148 #undef CL
149 }
150 
151 ATF_TC(clock_gettime_real);
152 ATF_TC_HEAD(clock_gettime_real, tc)
153 {
154 	atf_tc_set_md_var(tc, "require.user", "root");
155 	atf_tc_set_md_var(tc, "descr",
156 	    "Checks the monotonicity of the CLOCK_REALTIME implementation");
157 	atf_tc_set_md_var(tc, "timeout", "300");
158 }
159 
160 ATF_TC_BODY(clock_gettime_real, tc)
161 {
162 	char name[128], cbuf[512], ctrbuf[10240];
163 	size_t cbufsiz = sizeof(cbuf);
164 	size_t ctrbufsiz = sizeof(ctrbuf);
165 	const char *p;
166 	char *save;
167 	int quality, n;
168 
169 	if (sysctlbyname(TC_HARDWARE, cbuf, &cbufsiz, NULL, 0) != 0) {
170 		(void)printf("\nChecking legacy time implementation "
171 		    "for %d seconds\n", TIMEOUT);
172 		check_timecounter();
173 		return;
174 		/* NOTREACHED */
175 	}
176 	(void)printf("%s = %s\n", TC_HARDWARE, cbuf);
177 	REQUIRE_LIBC(save = strdup(cbuf), NULL);
178 
179 	RL(sysctlbyname(TC_CHOICE, ctrbuf, &ctrbufsiz, NULL, 0));
180 	(void)printf("%s = %s\n", TC_CHOICE, ctrbuf);
181 
182 	for (p = ctrbuf, n = 0; sscanf(p, "%127[^(](q=%d, f=%*u Hz)%*[ ]%n",
183 	    name, &quality, &n) == 2; p += n) {
184 		struct timespec ts;
185 		int ret;
186 
187 		if (quality < 0)
188 			continue;
189 
190 		(void)printf("\nChecking %s for %d seconds\n", name, TIMEOUT);
191 		CHECK_LIBC(ret = sysctlbyname(TC_HARDWARE, NULL, 0,
192 		    name, strlen(name)), -1);
193 		if (ret == -1)
194 			continue;
195 
196 		/* wait a bit to select new counter in clockinterrupt */
197 		ts.tv_sec = 0;
198 		ts.tv_nsec = 100000000;
199 		(void)nanosleep(&ts, NULL);
200 
201 		check_timecounter();
202 	}
203 
204 	RL(sysctlbyname(TC_HARDWARE, NULL, 0, save, strlen(save)));
205 }
206 
207 ATF_TP_ADD_TCS(tp)
208 {
209 
210 	ATF_TP_ADD_TC(tp, clock_gettime_real);
211 
212 	return atf_no_error();
213 }
214