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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[] = "Time of Wakeup After Timed Wait";
static char doc[] =
"\tThe time required for the highest-priority thread to resume\n"
"\texecution after a call to pthread_cond_timedwait(). Metrics\n"
"\tare provided for both the cases when the pthread_cond_timedwait()\n"
"\tcall is awakened by a call to pthread_cond_signal() and when\n"
"\tthe absolute time to be awaited has already passed at the time\n"
"\tof the call.";
pthread_mutex_t m1, m2;
pthread_cond_t c;
bench_t b;
struct timespec waketime;
void *
other_thread(arg)
void *arg;
{
pthread_set_name_np(pthread_self(), "oth");
pthread_mutex_lock(&m2);
bench_amortize(&b, BENCH_LOOPS) {
pthread_cond_timedwait(&c, &m2, &waketime);
pthread_cond_signal(&c);
}
pthread_mutex_unlock(&m2);
}
int
main() {
pthread_t other;
pthread_mutex_t m;
struct timespec ts;
bench_init(&b, name, doc, "from signal to wait inclusive");
b.n = BENCH_LOOPS;
bench_header(&b);
pthread_cond_init(&c, NULL);
pthread_mutex_init(&m1, NULL);
pthread_mutex_init(&m2, NULL);
clock_gettime(CLOCK_REALTIME, &waketime);
waketime.tv_sec += 10000; /* shouldn't take this long! */
pthread_mutex_lock(&m1);
pthread_create(&other, NULL, other_thread, NULL);
sched_yield();
while (b.i < b.n) {
pthread_cond_signal(&c);
pthread_cond_timedwait(&c, &m1, &waketime);
}
pthread_join(other, NULL);
pthread_mutex_unlock(&m1);
b.divisor = 2;
bench_report(&b);
/* expired test */
bench_init(&b, NULL, NULL, "per call when already expired");
pthread_mutex_init(&m, NULL);
pthread_mutex_lock(&m);
timespecclear(&ts); /* 1 Jan, 1970 */
bench_amortize(&b, BENCH_LOOPS) {
pthread_cond_timedwait(&c, &m, &ts);
}
pthread_mutex_unlock(&m);
bench_report(&b);
exit(0);
}
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