void *block_thread(void* arg)
{
assert(!in_vcore_context());
for (int i = 0; i < NUM_TEST_LOOPS; i++) {
printf_safe("[A] pthread %d on vcore %d\n", pthread_self()->id, vcore_id());
sys_block(5000 + pthread_self()->id);
}
return (void*)(long)pthread_self()->id;
}
static void *timer_thread(void *arg)
{
struct futex_element *e,*n = NULL;
struct futex_queue q = TAILQ_HEAD_INITIALIZER(q);
// Do this forever...
for(;;) {
// Block for 1 millisecond
sys_block(1000);
// Then atomically do the following...
mcs_pdr_lock(&__futex.lock);
// Up the time
__futex.time++;
// Find all futexes that have timed out on this iteration,
// and count those still waiting
int waiting = 0;
e = TAILQ_FIRST(&__futex.queue);
while(e != NULL) {
n = TAILQ_NEXT(e, link);
if(e->ms_timeout == __futex.time) {
e->timedout = true;
TAILQ_REMOVE(&__futex.queue, e, link);
TAILQ_INSERT_TAIL(&q, e, link);
}
else if(e->ms_timeout != (uint64_t)-1)
waiting++;
e = n;
}
// If there are no more waiting, disable the timer
if(waiting == 0) {
__futex.time = 0;
__futex.timer_enabled = false;
}
mcs_pdr_unlock(&__futex.lock);
// Unblock any futexes that have timed out outside the lock
e = TAILQ_FIRST(&q);
while(e != NULL) {
n = TAILQ_NEXT(e, link);
TAILQ_REMOVE(&q, e, link);
while(e->pthread == NULL)
cpu_relax();
uthread_runnable((struct uthread*)e->pthread);
e = n;
}
// If we have disabled the timer, park this thread
futex_wait(&__futex.timer_enabled, false, -1);
}
}
int main(int argc, char **argv)
{
int sleep_time;
if (argc < 2) {
printf("Usage: %s SEC\n", argv[0]);
exit(-1);
}
sleep_time = atoi(argv[1]);
if (sleep_time < 0)
exit(-1);
sys_block(sleep_time * 1000000);
return 0;
}
