linux/tools/testing/selftests/timers/clocksource-switch.c
Wolfram Sang ce7d101750 selftests: timers: clocksource-switch: adapt to kselftest framework
So we have proper counters at the end of a test. We also print the
kselftest header at the end of the test, so we don't mix with the output
of the child process. There is only this one test anyhow.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: John Stultz <jstultz@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-07-14 14:36:52 -06:00

192 lines
4.0 KiB
C

/* Clocksource change test
* by: john stultz (johnstul@us.ibm.com)
* (C) Copyright IBM 2012
* Licensed under the GPLv2
*
* NOTE: This is a meta-test which quickly changes the clocksource and
* then uses other tests to detect problems. Thus this test requires
* that the inconsistency-check and nanosleep tests be present in the
* same directory it is run from.
*
* To build:
* $ gcc clocksource-switch.c -o clocksource-switch -lrt
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/timex.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>
#include "../kselftest.h"
int get_clocksources(char list[][30])
{
int fd, i;
size_t size;
char buf[512];
char *head, *tmp;
fd = open("/sys/devices/system/clocksource/clocksource0/available_clocksource", O_RDONLY);
size = read(fd, buf, 512);
close(fd);
for (i = 0; i < 10; i++)
list[i][0] = '\0';
head = buf;
i = 0;
while (head - buf < size) {
/* Find the next space */
for (tmp = head; *tmp != ' '; tmp++) {
if (*tmp == '\n')
break;
if (*tmp == '\0')
break;
}
*tmp = '\0';
strcpy(list[i], head);
head = tmp + 1;
i++;
}
return i-1;
}
int get_cur_clocksource(char *buf, size_t size)
{
int fd;
fd = open("/sys/devices/system/clocksource/clocksource0/current_clocksource", O_RDONLY);
size = read(fd, buf, size);
return 0;
}
int change_clocksource(char *clocksource)
{
int fd;
ssize_t size;
fd = open("/sys/devices/system/clocksource/clocksource0/current_clocksource", O_WRONLY);
if (fd < 0)
return -1;
size = write(fd, clocksource, strlen(clocksource));
if (size < 0)
return -1;
close(fd);
return 0;
}
int run_tests(int secs)
{
int ret;
char buf[255];
sprintf(buf, "./inconsistency-check -t %i", secs);
ret = system(buf);
if (WIFEXITED(ret) && WEXITSTATUS(ret))
return WEXITSTATUS(ret);
ret = system("./nanosleep");
return WIFEXITED(ret) ? WEXITSTATUS(ret) : 0;
}
char clocksource_list[10][30];
int main(int argc, char **argv)
{
char orig_clk[512];
int count, i, status, opt;
int do_sanity_check = 1;
int runtime = 60;
pid_t pid;
/* Process arguments */
while ((opt = getopt(argc, argv, "st:")) != -1) {
switch (opt) {
case 's':
do_sanity_check = 0;
break;
case 't':
runtime = atoi(optarg);
break;
default:
printf("Usage: %s [-s] [-t <secs>]\n", argv[0]);
printf(" -s: skip sanity checks\n");
printf(" -t: Number of seconds to run\n");
exit(-1);
}
}
get_cur_clocksource(orig_clk, 512);
count = get_clocksources(clocksource_list);
if (change_clocksource(clocksource_list[0])) {
printf("Error: You probably need to run this as root\n");
return -1;
}
/* Check everything is sane before we start switching asynchronously */
if (do_sanity_check) {
for (i = 0; i < count; i++) {
printf("Validating clocksource %s\n",
clocksource_list[i]);
if (change_clocksource(clocksource_list[i])) {
status = -1;
goto out;
}
if (run_tests(5)) {
status = -1;
goto out;
}
}
}
printf("Running Asynchronous Switching Tests...\n");
pid = fork();
if (!pid)
return run_tests(runtime);
while (pid != waitpid(pid, &status, WNOHANG))
for (i = 0; i < count; i++)
if (change_clocksource(clocksource_list[i])) {
status = -1;
goto out;
}
out:
change_clocksource(orig_clk);
/* Print at the end to not mix output with child process */
ksft_print_header();
ksft_set_plan(1);
ksft_test_result(!status, "clocksource-switch\n");
ksft_exit(!status);
}