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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194/* threadtest.c * by: john stultz (johnstul@us.ibm.com) * (C) Copyright IBM 2004, 2005, 2006, 2012 * Licensed under the GPLv2 * * To build: * $ gcc threadtest.c -o threadtest -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 <stdio.h>#include <unistd.h>#include <stdlib.h>#include <sys/time.h>#include <pthread.h>#include "kselftest.h"
/* serializes shared list access */pthread_mutex_t list_lock = PTHREAD_MUTEX_INITIALIZER;/* serializes console output */pthread_mutex_t print_lock = PTHREAD_MUTEX_INITIALIZER;
#define MAX_THREADS 128#define LISTSIZE 128
int done = 0;
struct timespec global_list[LISTSIZE];int listcount = 0;
void checklist(const struct timespec *list, int size){ int i, j; const struct timespec *a, *b;
/* scan the list */ for (i = 0; i < size-1; i++) { a = &list[i]; b = &list[i+1];
/* look for any time inconsistencies */ if ((b->tv_sec <= a->tv_sec) && (b->tv_nsec < a->tv_nsec)) {
/* flag other threads */ done = 1;
/*serialize printing to avoid junky output*/ pthread_mutex_lock(&print_lock);
/* dump the list */ printf("\n"); for (j = 0; j < size; j++) { if (j == i) printf("---------------\n"); printf("%lu:%lu\n", list[j].tv_sec, list[j].tv_nsec); if (j == i+1) printf("---------------\n"); } printf("[FAILED]\n");
pthread_mutex_unlock(&print_lock); } }}
/* The shared thread shares a global list * that each thread fills while holding the lock. * This stresses clock synchronization across cpus. */void *shared_thread(void *arg){ while (!done) { /* protect the list */ pthread_mutex_lock(&list_lock);
/* see if we're ready to check the list */ if (listcount >= LISTSIZE) { checklist(global_list, LISTSIZE); listcount = 0; } clock_gettime(CLOCK_MONOTONIC, &global_list[listcount++]);
pthread_mutex_unlock(&list_lock); } return NULL;}
/* Each independent thread fills in its own * list. This stresses clock_gettime() lock contention. */void *independent_thread(void *arg){ struct timespec my_list[LISTSIZE]; int count;
while (!done) { /* fill the list */ for (count = 0; count < LISTSIZE; count++) clock_gettime(CLOCK_MONOTONIC, &my_list[count]); checklist(my_list, LISTSIZE); } return NULL;}
#define DEFAULT_THREAD_COUNT 8#define DEFAULT_RUNTIME 30
int main(int argc, char **argv){ int thread_count, i; time_t start, now, runtime; char buf[255]; pthread_t pth[MAX_THREADS]; int opt; void *tret; int ret = 0; void *(*thread)(void *) = shared_thread;
thread_count = DEFAULT_THREAD_COUNT; runtime = DEFAULT_RUNTIME;
/* Process arguments */ while ((opt = getopt(argc, argv, "t:n:i")) != -1) { switch (opt) { case 't': runtime = atoi(optarg); break; case 'n': thread_count = atoi(optarg); break; case 'i': thread = independent_thread; printf("using independent threads\n"); break; default: printf("Usage: %s [-t <secs>] [-n <numthreads>] [-i]\n", argv[0]); printf(" -t: time to run\n"); printf(" -n: number of threads\n"); printf(" -i: use independent threads\n"); return -1; } }
if (thread_count > MAX_THREADS) thread_count = MAX_THREADS;
setbuf(stdout, NULL);
start = time(0); strftime(buf, 255, "%a, %d %b %Y %T %z", localtime(&start)); printf("%s\n", buf); printf("Testing consistency with %i threads for %ld seconds: ", thread_count, runtime); fflush(stdout);
/* spawn */ for (i = 0; i < thread_count; i++) pthread_create(&pth[i], 0, thread, 0);
while (time(&now) < start + runtime) { sleep(1); if (done) { ret = 1; strftime(buf, 255, "%a, %d %b %Y %T %z", localtime(&now)); printf("%s\n", buf); goto out; } } printf("[OK]\n"); done = 1;
out: /* wait */ for (i = 0; i < thread_count; i++) pthread_join(pth[i], &tret);
/* die */ if (ret) ksft_exit_fail(); ksft_exit_pass();}