diff options
Diffstat (limited to 'tools/testing/selftests/timers/clocksource-switch.c')
| -rw-r--r-- | tools/testing/selftests/timers/clocksource-switch.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/tools/testing/selftests/timers/clocksource-switch.c b/tools/testing/selftests/timers/clocksource-switch.c new file mode 100644 index 0000000000..c526459406 --- /dev/null +++ b/tools/testing/selftests/timers/clocksource-switch.c @@ -0,0 +1,191 @@ +/* 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); +} |