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 #include "../kselftest.h"
32 
33 #define CALLS_PER_LOOP 64
34 #define NSEC_PER_SEC 1000000000ULL
35 
36 #define CLOCK_REALTIME			0
37 #define CLOCK_MONOTONIC			1
38 #define CLOCK_PROCESS_CPUTIME_ID	2
39 #define CLOCK_THREAD_CPUTIME_ID		3
40 #define CLOCK_MONOTONIC_RAW		4
41 #define CLOCK_REALTIME_COARSE		5
42 #define CLOCK_MONOTONIC_COARSE		6
43 #define CLOCK_BOOTTIME			7
44 #define CLOCK_REALTIME_ALARM		8
45 #define CLOCK_BOOTTIME_ALARM		9
46 #define CLOCK_HWSPECIFIC		10
47 #define CLOCK_TAI			11
48 #define NR_CLOCKIDS			12
49 
clockstring(int clockid)50 char *clockstring(int clockid)
51 {
52 	switch (clockid) {
53 	case CLOCK_REALTIME:
54 		return "CLOCK_REALTIME";
55 	case CLOCK_MONOTONIC:
56 		return "CLOCK_MONOTONIC";
57 	case CLOCK_PROCESS_CPUTIME_ID:
58 		return "CLOCK_PROCESS_CPUTIME_ID";
59 	case CLOCK_THREAD_CPUTIME_ID:
60 		return "CLOCK_THREAD_CPUTIME_ID";
61 	case CLOCK_MONOTONIC_RAW:
62 		return "CLOCK_MONOTONIC_RAW";
63 	case CLOCK_REALTIME_COARSE:
64 		return "CLOCK_REALTIME_COARSE";
65 	case CLOCK_MONOTONIC_COARSE:
66 		return "CLOCK_MONOTONIC_COARSE";
67 	case CLOCK_BOOTTIME:
68 		return "CLOCK_BOOTTIME";
69 	case CLOCK_REALTIME_ALARM:
70 		return "CLOCK_REALTIME_ALARM";
71 	case CLOCK_BOOTTIME_ALARM:
72 		return "CLOCK_BOOTTIME_ALARM";
73 	case CLOCK_TAI:
74 		return "CLOCK_TAI";
75 	};
76 	return "UNKNOWN_CLOCKID";
77 }
78 
79 /* returns 1 if a <= b, 0 otherwise */
in_order(struct timespec a,struct timespec b)80 static inline int in_order(struct timespec a, struct timespec b)
81 {
82 	/* use unsigned to avoid false positives on 2038 rollover */
83 	if ((unsigned long)a.tv_sec < (unsigned long)b.tv_sec)
84 		return 1;
85 	if ((unsigned long)a.tv_sec > (unsigned long)b.tv_sec)
86 		return 0;
87 	if (a.tv_nsec > b.tv_nsec)
88 		return 0;
89 	return 1;
90 }
91 
92 
93 
consistency_test(int clock_type,unsigned long seconds)94 int consistency_test(int clock_type, unsigned long seconds)
95 {
96 	struct timespec list[CALLS_PER_LOOP];
97 	int i, inconsistent;
98 	long now, then;
99 	time_t t;
100 	char *start_str;
101 
102 	clock_gettime(clock_type, &list[0]);
103 	now = then = list[0].tv_sec;
104 
105 	/* timestamp start of test */
106 	t = time(0);
107 	start_str = ctime(&t);
108 
109 	while (seconds == -1 || now - then < seconds) {
110 		inconsistent = -1;
111 
112 		/* Fill list */
113 		for (i = 0; i < CALLS_PER_LOOP; i++)
114 			clock_gettime(clock_type, &list[i]);
115 
116 		/* Check for inconsistencies */
117 		for (i = 0; i < CALLS_PER_LOOP - 1; i++)
118 			if (!in_order(list[i], list[i+1]))
119 				inconsistent = i;
120 
121 		/* display inconsistency */
122 		if (inconsistent >= 0) {
123 			unsigned long long delta;
124 
125 			printf("\%s\n", start_str);
126 			for (i = 0; i < CALLS_PER_LOOP; i++) {
127 				if (i == inconsistent)
128 					printf("--------------------\n");
129 				printf("%lu:%lu\n", list[i].tv_sec,
130 							list[i].tv_nsec);
131 				if (i == inconsistent + 1)
132 					printf("--------------------\n");
133 			}
134 			delta = list[inconsistent].tv_sec * NSEC_PER_SEC;
135 			delta += list[inconsistent].tv_nsec;
136 			delta -= list[inconsistent+1].tv_sec * NSEC_PER_SEC;
137 			delta -= list[inconsistent+1].tv_nsec;
138 			printf("Delta: %llu ns\n", delta);
139 			fflush(0);
140 			/* timestamp inconsistency*/
141 			t = time(0);
142 			printf("%s\n", ctime(&t));
143 			printf("[FAILED]\n");
144 			return -1;
145 		}
146 		now = list[0].tv_sec;
147 	}
148 	printf("[OK]\n");
149 	return 0;
150 }
151 
152 
main(int argc,char * argv[])153 int main(int argc, char *argv[])
154 {
155 	int clockid, opt;
156 	int userclock = CLOCK_REALTIME;
157 	int maxclocks = NR_CLOCKIDS;
158 	int runtime = 10;
159 	struct timespec ts;
160 
161 	/* Process arguments */
162 	while ((opt = getopt(argc, argv, "t:c:")) != -1) {
163 		switch (opt) {
164 		case 't':
165 			runtime = atoi(optarg);
166 			break;
167 		case 'c':
168 			userclock = atoi(optarg);
169 			maxclocks = userclock + 1;
170 			break;
171 		default:
172 			printf("Usage: %s [-t <secs>] [-c <clockid>]\n", argv[0]);
173 			printf("	-t: Number of seconds to run\n");
174 			printf("	-c: clockid to use (default, all clockids)\n");
175 			exit(-1);
176 		}
177 	}
178 
179 	setbuf(stdout, NULL);
180 
181 	for (clockid = userclock; clockid < maxclocks; clockid++) {
182 
183 		if (clockid == CLOCK_HWSPECIFIC)
184 			continue;
185 
186 		if (!clock_gettime(clockid, &ts)) {
187 			printf("Consistent %-30s ", clockstring(clockid));
188 			if (consistency_test(clockid, runtime))
189 				return ksft_exit_fail();
190 		}
191 	}
192 	return ksft_exit_pass();
193 }
194