#include <rtl.h>#include <time.h>#include <rtl_time.h>#include <pthread.h>pthread_t thread;hrtime_t start_nanosec;void * start_routine(void *arg){	struct sched_param p;	hrtime_t elapsed_time,now;	p . sched_priority = 1;	pthread_setschedparam (pthread_self(), SCHED_FIFO, &p);	pthread_make_periodic_np (pthread_self(), gethrtime(), 500000000);	while (1) {		pthread_wait_np ();		now = clock_gethrtime(CLOCK_REALTIME);		elapsed_time = now - start_nanosec;		rtl_printf("elapsed_time = %Ld\n",(long long)elapsed_time);	}	return 0;}int init_module(void) {	start_nanosec = clock_gethrtime(CLOCK_REALTIME);	return pthread_create (&thread, NULL, start_routine, 0);}void cleanup_module(void) {	pthread_delete_np (thread);}