#include #include #include 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); }