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
34static inline int ksft_exit_pass(void)
35{
36	exit(0);
37}
38static 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
61char *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 */
91static 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
105int 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
164int 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