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      1 /* Time inconsistency check test
      2  *		by: john stultz (johnstul (at) 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 
     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 */
     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 
     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 
    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