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#include <stdio.h>
#include <pthread.h>
#include <sched.h>
#include <string.h>
#include <err.h>
#include "bench.h"
static char name[] = "Condition Variable, Wake Up";
static char doc[] =
"\tThis is the amount of time from when one thread calls\n"
"\tpthread_cond_signal() and a thread blocked on that condition\n"
"\tvariable returns from its pthread_cond_wait() call. The condition\n"
"\tand its associated mutex should not be used by any other thread.\n"
"\tMetrics shall be provided for both the case when the\n"
"\tpthread_cond_signal() call is executed under the associated mutex,\n"
"\tas well as not under the mutex.";
/* BROKEN */
pthread_mutex_t m1, m2;
pthread_cond_t c;
bench_t b;
void *
other_thread(arg)
void *arg;
{
pthread_set_name_np(pthread_self(), "oth");
pthread_mutex_lock(&m2);
bench_amortize(&b, BENCH_LOOPS) {
pthread_cond_wait(&c, &m2);
pthread_cond_signal(&c);
}
pthread_mutex_unlock(&m2);
}
int
main() {
pthread_t other;
bench_init(&b, name, doc, "per call");
b.n = BENCH_LOOPS;
bench_header(&b);
pthread_cond_init(&c, NULL);
pthread_mutex_init(&m1, NULL);
pthread_mutex_init(&m2, NULL);
pthread_mutex_lock(&m1);
pthread_create(&other, NULL, other_thread, NULL);
sched_yield();
while (b.i < b.n) {
pthread_cond_signal(&c);
pthread_cond_wait(&c, &m1);
}
b.divisor = 2;
bench_report(&b);
pthread_join(other, NULL);
exit(0);
}
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