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#include <rtl.h>
#include <time.h>
#include <pthread.h>
static pthread_t thread;
static pthread_mutex_t mutex /* = PTHREAD_MUTEX_INITIALIZER */;
static pthread_cond_t cond;
static int timed=1;
MODULE_PARM(timed,"i");
static void * start_routine(void *arg)
{
int ret;
hrtime_t t;
hrtime_t t2;
struct sched_param p;
p . sched_priority = 1;
pthread_setschedparam (pthread_self(), SCHED_FIFO, &p);
rtl_printf("RTLinux thread starts on CPU%d\n", rtl_getcpuid());
if (timed) {
rtl_printf("RT-thread: about to pthread_cond_timedwait\n");
t = clock_gethrtime(CLOCK_REALTIME);
pthread_mutex_lock (&mutex);
ret = pthread_cond_timedwait (&cond, &mutex, hrt2ts(t + 2000000));
pthread_mutex_unlock (&mutex);
t2 = clock_gethrtime(CLOCK_REALTIME);
rtl_printf("RT-thread: pthread_cond_timedwait returned %d (%d ns elapsed)\n", ret, (unsigned) (t2 - t));
}
rtl_printf("RT-thread: about to pthread_cond_wait\n");
t = clock_gethrtime(CLOCK_REALTIME);
pthread_mutex_lock (&mutex);
ret = pthread_cond_wait (&cond, &mutex);
pthread_mutex_unlock (&mutex);
t2 = clock_gethrtime(CLOCK_REALTIME);
rtl_printf("RT-thread: pthread_cond_wait returned %d (%d ns elapsed)\n", ret, (unsigned) (t2 - t));
return (void *) 35;
}
int init_module(void)
{
int ret;
hrtime_t t;
int sleep = 500000000;
pthread_attr_t attr;
rtl_printf("RTLinux condvar test starts on CPU%d\n", rtl_getcpuid());
pthread_attr_init (&attr);
/* try to run the thread on another CPU */
if (rtl_cpu_exists(!rtl_getcpuid())) {
pthread_attr_setcpu_np(&attr, !rtl_getcpuid());
}
pthread_mutex_init (&mutex, NULL);
pthread_cond_init (&cond, NULL);
ret = pthread_create (&thread, &attr, start_routine, 0);
if (ret) {
rtl_printf("failed to create a thread\n");
return ret;
}
rtl_printf("Linux thread is about to busy-wait for %d ns\n", sleep);
t = gethrtime();
while (gethrtime() < t + sleep);
rtl_printf("Linux thread is about to signal the condition\n");
pthread_mutex_lock (&mutex);
ret = pthread_cond_signal (&cond);
pthread_mutex_unlock (&mutex);
rtl_printf("Linux thread: pthread_cond_signal returned %d\n", ret);
return 0;
}
void cleanup_module(void)
{
void *retval;
pthread_cancel (thread);
pthread_join (thread, &retval);
/* rtl_printf("RTLinux mutex: joined thread returned %d\n", (int) retval); */
pthread_mutex_destroy (&mutex);
}
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