1 /* Time inconsistency check test
2  *		by: john stultz (johnstul@us.ibm.com)
3  *		(C) Copyright IBM 2003, 2004, 2005, 2012
4  *		(C) Copyright Linaro Limited 2015
5  *		Licensed under the GPLv2
6  *
7  *  To build:
8  *	$ gcc inconsistency-check.c -o inconsistency-check -lrt
9  *
10  *   This program is free software: you can redistribute it and/or modify
11  *   it under the terms of the GNU General Public License as published by
12  *   the Free Software Foundation, either version 2 of the License, or
13  *   (at your option) any later version.
14  *
15  *   This program is distributed in the hope that it will be useful,
16  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *   GNU General Public License for more details.
19  */
20 
21 
22 
23 #include <stdio.h>
24 #include <unistd.h>
25 #include <stdlib.h>
26 #include <time.h>
27 #include <sys/time.h>
28 #include <sys/timex.h>
29 #include <string.h>
30 #include <signal.h>
31 #ifdef KTEST
32 #include "../kselftest.h"
33 #else
34 static inline int ksft_exit_pass(void)
35 {
36 	exit(0);
37 }
38 static inline int ksft_exit_fail(void)
39 {
40 	exit(1);
41 }
42 #endif
43 
44 #define CALLS_PER_LOOP 64
45 #define NSEC_PER_SEC 1000000000ULL
46 
47 #define CLOCK_REALTIME			0
48 #define CLOCK_MONOTONIC			1
49 #define CLOCK_PROCESS_CPUTIME_ID	2
50 #define CLOCK_THREAD_CPUTIME_ID		3
51 #define CLOCK_MONOTONIC_RAW		4
52 #define CLOCK_REALTIME_COARSE		5
53 #define CLOCK_MONOTONIC_COARSE		6
54 #define CLOCK_BOOTTIME			7
55 #define CLOCK_REALTIME_ALARM		8
56 #define CLOCK_BOOTTIME_ALARM		9
57 #define CLOCK_HWSPECIFIC		10
58 #define CLOCK_TAI			11
59 #define NR_CLOCKIDS			12
60 
61 char *clockstring(int clockid)
62 {
63 	switch (clockid) {
64 	case CLOCK_REALTIME:
65 		return "CLOCK_REALTIME";
66 	case CLOCK_MONOTONIC:
67 		return "CLOCK_MONOTONIC";
68 	case CLOCK_PROCESS_CPUTIME_ID:
69 		return "CLOCK_PROCESS_CPUTIME_ID";
70 	case CLOCK_THREAD_CPUTIME_ID:
71 		return "CLOCK_THREAD_CPUTIME_ID";
72 	case CLOCK_MONOTONIC_RAW:
73 		return "CLOCK_MONOTONIC_RAW";
74 	case CLOCK_REALTIME_COARSE:
75 		return "CLOCK_REALTIME_COARSE";
76 	case CLOCK_MONOTONIC_COARSE:
77 		return "CLOCK_MONOTONIC_COARSE";
78 	case CLOCK_BOOTTIME:
79 		return "CLOCK_BOOTTIME";
80 	case CLOCK_REALTIME_ALARM:
81 		return "CLOCK_REALTIME_ALARM";
82 	case CLOCK_BOOTTIME_ALARM:
83 		return "CLOCK_BOOTTIME_ALARM";
84 	case CLOCK_TAI:
85 		return "CLOCK_TAI";
86 	};
87 	return "UNKNOWN_CLOCKID";
88 }
89 
90 /* returns 1 if a <= b, 0 otherwise */
91 static inline int in_order(struct timespec a, struct timespec b)
92 {
93 	/* use unsigned to avoid false positives on 2038 rollover */
94 	if ((unsigned long)a.tv_sec < (unsigned long)b.tv_sec)
95 		return 1;
96 	if ((unsigned long)a.tv_sec > (unsigned long)b.tv_sec)
97 		return 0;
98 	if (a.tv_nsec > b.tv_nsec)
99 		return 0;
100 	return 1;
101 }
102 
103 
104 
105 int consistency_test(int clock_type, unsigned long seconds)
106 {
107 	struct timespec list[CALLS_PER_LOOP];
108 	int i, inconsistent;
109 	long now, then;
110 	time_t t;
111 	char *start_str;
112 
113 	clock_gettime(clock_type, &list[0]);
114 	now = then = list[0].tv_sec;
115 
116 	/* timestamp start of test */
117 	t = time(0);
118 	start_str = ctime(&t);
119 
120 	while (seconds == -1 || now - then < seconds) {
121 		inconsistent = 0;
122 
123 		/* Fill list */
124 		for (i = 0; i < CALLS_PER_LOOP; i++)
125 			clock_gettime(clock_type, &list[i]);
126 
127 		/* Check for inconsistencies */
128 		for (i = 0; i < CALLS_PER_LOOP - 1; i++)
129 			if (!in_order(list[i], list[i+1]))
130 				inconsistent = i;
131 
132 		/* display inconsistency */
133 		if (inconsistent) {
134 			unsigned long long delta;
135 
136 			printf("\%s\n", start_str);
137 			for (i = 0; i < CALLS_PER_LOOP; i++) {
138 				if (i == inconsistent)
139 					printf("--------------------\n");
140 				printf("%lu:%lu\n", list[i].tv_sec,
141 							list[i].tv_nsec);
142 				if (i == inconsistent + 1)
143 					printf("--------------------\n");
144 			}
145 			delta = list[inconsistent].tv_sec * NSEC_PER_SEC;
146 			delta += list[inconsistent].tv_nsec;
147 			delta -= list[inconsistent+1].tv_sec * NSEC_PER_SEC;
148 			delta -= list[inconsistent+1].tv_nsec;
149 			printf("Delta: %llu ns\n", delta);
150 			fflush(0);
151 			/* timestamp inconsistency*/
152 			t = time(0);
153 			printf("%s\n", ctime(&t));
154 			printf("[FAILED]\n");
155 			return -1;
156 		}
157 		now = list[0].tv_sec;
158 	}
159 	printf("[OK]\n");
160 	return 0;
161 }
162 
163 
164 int main(int argc, char *argv[])
165 {
166 	int clockid, opt;
167 	int userclock = CLOCK_REALTIME;
168 	int maxclocks = NR_CLOCKIDS;
169 	int runtime = 10;
170 	struct timespec ts;
171 
172 	/* Process arguments */
173 	while ((opt = getopt(argc, argv, "t:c:")) != -1) {
174 		switch (opt) {
175 		case 't':
176 			runtime = atoi(optarg);
177 			break;
178 		case 'c':
179 			userclock = atoi(optarg);
180 			maxclocks = userclock + 1;
181 			break;
182 		default:
183 			printf("Usage: %s [-t <secs>] [-c <clockid>]\n", argv[0]);
184 			printf("	-t: Number of seconds to run\n");
185 			printf("	-c: clockid to use (default, all clockids)\n");
186 			exit(-1);
187 		}
188 	}
189 
190 	setbuf(stdout, NULL);
191 
192 	for (clockid = userclock; clockid < maxclocks; clockid++) {
193 
194 		if (clockid == CLOCK_HWSPECIFIC)
195 			continue;
196 
197 		if (!clock_gettime(clockid, &ts)) {
198 			printf("Consistent %-30s ", clockstring(clockid));
199 			if (consistency_test(clockid, runtime))
200 				return ksft_exit_fail();
201 		}
202 	}
203 	return ksft_exit_pass();
204 }
205