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#include <rtl.h>
#include <time.h>
#include <pthread.h>
#define NTASKS 3
static pthread_t threads[NTASKS];
static pthread_mutex_t mutex /* = PTHREAD_MUTEX_INITIALIZER */;
static void * start_routine(void *arg)
{
int ret;
hrtime_t t;
hrtime_t t2;
int sleep = 500000000;
int nthread = (int) arg;
struct sched_param p;
p . sched_priority = 1;
pthread_setschedparam (pthread_self(), SCHED_FIFO, &p);
rtl_printf("thread %d starts on CPU%d\n", nthread, rtl_getcpuid());
ret = pthread_mutex_trylock(&mutex);
rtl_printf ("thread %d: pthread_mutex_trylock returned %d\n", nthread, ret);
if (ret != 0) {
rtl_printf("thread %d: about to pthread_mutex_lock\n", nthread);
t = gethrtime();
ret = pthread_mutex_lock (&mutex);
t2 = gethrtime();
rtl_printf("thread %d: pthread_mutex_lock returned %d (%d ns elapsed)\n", nthread, ret, (unsigned) (t2 - t));
}
rtl_printf("thread %d is about to sleep for %d ns\n", nthread, sleep);
nanosleep (hrt2ts(sleep), NULL);
ret = pthread_mutex_unlock (&mutex);
rtl_printf("thread %d: pthread_mutex_unlock returned %d\n", nthread, ret);
return (void *) 35 + nthread;
}
int init_module(void)
{
int ret;
int i;
pthread_attr_t attr;
pthread_mutex_init (&mutex, 0);
rtl_printf("RTLinux mutex test starts on CPU%d\n", rtl_getcpuid());
pthread_attr_init (&attr);
for (i = 0; i < NTASKS; i++) {
/* try to run one thread on another CPU */
if (i == 1 && rtl_cpu_exists(!rtl_getcpuid())) {
pthread_attr_setcpu_np(&attr, !rtl_getcpuid());
}
ret = pthread_create (&threads[i], &attr, start_routine, (void *) i);
if (ret) {
rtl_printf("failed to create a thread\n");
return ret;
}
}
return 0;
}
void cleanup_module(void)
{
void *retval;
int i;
for (i = 0; i < 3; i++) {
pthread_join (threads[i], &retval);
rtl_printf("pthread_join on thread %d returned %d\n", i, (int) retval);
}
pthread_mutex_destroy (&mutex);
}
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