1 /* ADJ_FREQ Skew change test 2 * by: john stultz (johnstul@us.ibm.com) 3 * (C) Copyright IBM 2012 4 * Licensed under the GPLv2 5 * 6 * NOTE: This is a meta-test which cranks the ADJ_FREQ knob and 7 * then uses other tests to detect problems. Thus this test requires 8 * that the raw_skew, inconsistency-check and nanosleep tests be 9 * present in the same directory it is run from. 10 * 11 * To build: 12 * $ gcc change_skew.c -o change_skew -lrt 13 * 14 * This program is free software: you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License as published by 16 * the Free Software Foundation, either version 2 of the License, or 17 * (at your option) any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22 * GNU General Public License for more details. 23 */ 24 25 26 #include <stdio.h> 27 #include <stdlib.h> 28 #include <sys/time.h> 29 #include <sys/timex.h> 30 #include <time.h> 31 #include "../kselftest.h" 32 33 int change_skew_test(int ppm) 34 { 35 struct timex tx; 36 int ret; 37 38 tx.modes = ADJ_FREQUENCY; 39 tx.freq = ppm << 16; 40 41 ret = adjtimex(&tx); 42 if (ret < 0) { 43 printf("Error adjusting freq\n"); 44 return ret; 45 } 46 47 ret = system("./raw_skew"); 48 ret |= system("./inconsistency-check"); 49 ret |= system("./nanosleep"); 50 51 return ret; 52 } 53 54 55 int main(int argc, char **argv) 56 { 57 struct timex tx; 58 int i, ret; 59 60 int ppm[5] = {0, 250, 500, -250, -500}; 61 62 /* Kill ntpd */ 63 ret = system("killall -9 ntpd"); 64 65 /* Make sure there's no offset adjustment going on */ 66 tx.modes = ADJ_OFFSET; 67 tx.offset = 0; 68 ret = adjtimex(&tx); 69 70 if (ret < 0) { 71 printf("Maybe you're not running as root?\n"); 72 return -1; 73 } 74 75 for (i = 0; i < 5; i++) { 76 printf("Using %i ppm adjustment\n", ppm[i]); 77 ret = change_skew_test(ppm[i]); 78 if (ret) 79 break; 80 } 81 82 /* Set things back */ 83 tx.modes = ADJ_FREQUENCY; 84 tx.offset = 0; 85 adjtimex(&tx); 86 87 if (ret) { 88 printf("[FAIL]"); 89 ksft_exit_fail(); 90 } 91 printf("[OK]"); 92 ksft_exit_pass(); 93 } 94