/* Fetch next ready thread. */
struct thread *
thread_fetch (struct lib_globals *zg, struct thread *fetch)
{
struct thread_master *m = zg->master;
int num;
struct thread *thread;
struct thread *next;
pal_sock_set_t readfd;
pal_sock_set_t writefd;
pal_sock_set_t exceptfd;
struct pal_timeval timer_now;
struct pal_timeval timer_val;
struct pal_timeval *timer_wait;
struct pal_timeval timer_nowait;
int i;
#ifdef RTOS_DEFAULT_WAIT_TIME
/* 1 sec might not be optimized */
timer_nowait.tv_sec = 1;
timer_nowait.tv_usec = 0;
#else
timer_nowait.tv_sec = 0;
timer_nowait.tv_usec = 0;
#endif /* RTOS_DEFAULT_WAIT_TIME */
/* Set the global VR context to PVR. */
zg->vr_in_cxt = ipi_vr_get_privileged(zg);
while (1)
{
/* Pending read is exception. */
if ((thread = thread_trim_head (&m->read_pend)) != NULL)
return thread_run (m, thread, fetch);
/* Check ready queue. */
if ((thread = thread_trim_head (&m->queue_high)) != NULL)
return thread_run (m, thread, fetch);
if ((thread = thread_trim_head (&m->queue_middle)) != NULL)
return thread_run (m, thread, fetch);
if ((thread = thread_trim_head (&m->queue_low)) != NULL)
return thread_run (m, thread, fetch);
/* Check all of available events. */
/* Check events. */
while ((thread = thread_trim_head (&m->event)) != NULL)
thread_enqueue_high (m, thread);
/* Check timer. */
pal_time_tzcurrent (&timer_now, NULL);
for (i = 0; i < THREAD_TIMER_SLOT; i++)
for (thread = m->timer[i].head; thread; thread = next)
{
next = thread->next;
if (timeval_cmp (timer_now, thread->u.sands) >= 0)
{
thread_list_delete (&m->timer[i], thread);
thread_enqueue_middle (m, thread);
}
#ifndef TIMER_NO_SORT
else
break;
#endif /* TIMER_NO_SORT */
}
/* Structure copy. */
readfd = m->readfd;
writefd = m->writefd;
exceptfd = m->exceptfd;
/* Check any thing to be execute. */
if (m->queue_high.head || m->queue_middle.head || m->queue_low.head)
timer_wait = &timer_nowait;
else
timer_wait = thread_timer_wait (m, &timer_val);
/* First check for sockets. Return immediately. */
num = pal_sock_select (m->max_fd + 1, &readfd, &writefd, &exceptfd,
timer_wait);
/* Error handling. */
if (num < 0)
{
if (errno == EINTR)
continue;
return NULL;
}
/* File descriptor is readable/writable. */
if (num > 0)
{
/* High priority read thead. */
thread_process_fd (m, &m->read_high, &readfd, &m->readfd);
/* Normal priority read thead. */
thread_process_fd (m, &m->read, &readfd, &m->readfd);
/* Write thead. */
thread_process_fd (m, &m->write, &writefd, &m->writefd);
}
/* Low priority events. */
if ((thread = thread_trim_head (&m->event_low)) != NULL)
thread_enqueue_low (m, thread);
}
}
/* Fetch next ready thread. */
struct thread *
thread_fetch_return (struct thread_master *master, struct thread *fetch)
{
struct thread_master *m = master;
int num;
struct thread *thread;
struct thread *next;
fd_set readfd;
fd_set writefd;
fd_set exceptfd;
struct pal_timeval timer_now;
struct pal_timeval timer_val;
struct pal_timeval *timer_wait;
struct pal_timeval timer_nowait;
int i;
timer_nowait.tv_sec = 0;
timer_nowait.tv_usec = 0;
/* Pending read is exception. */
if ((thread = thread_trim_head (&m->read_pend)) != NULL)
return thread_run (m, thread, fetch);
/* Check ready queue. */
if ((thread = thread_trim_head (&m->queue_high)) != NULL)
return thread_run (m, thread, fetch);
if ((thread = thread_trim_head (&m->queue_middle)) != NULL)
return thread_run (m, thread, fetch);
if ((thread = thread_trim_head (&m->queue_low)) != NULL)
return thread_run (m, thread, fetch);
/* Check all of available events. */
/* Check events. */
while ((thread = thread_trim_head (&m->event)) != NULL)
thread_enqueue_high (m, thread);
/* Check timer. */
pal_time_tzcurrent (&timer_now, NULL);
for (i = 0; i < THREAD_TIMER_SLOT; i++)
for (thread = m->timer[i].head; thread; thread = next)
{
next = thread->next;
if (timeval_cmp (timer_now, thread->u.sands) >= 0)
{
thread_list_delete (&m->timer[i], thread);
thread_enqueue_middle (m, thread);
}
#ifndef TIMER_NO_SORT
else
break;
#endif /* TIMER_NO_SORT */
}
/* Structure copy. */
readfd = m->readfd;
writefd = m->writefd;
exceptfd = m->exceptfd;
/* Check any thing to be execute. */
if (m->queue_high.head || m->queue_middle.head || m->queue_low.head)
timer_wait = &timer_nowait;
else
timer_wait = thread_timer_wait (m, &timer_val);
timer_wait = &timer_nowait;
/* First check for sockets. Return immediately. */
num = select (m->max_fd + 1, &readfd, &writefd, &exceptfd,
timer_wait);
/* Error handling. */
if (num < 0)
{
return NULL;
}
/* File descriptor is readable/writable. */
if (num > 0)
{
/* High priority read thead. */
thread_process_fd (m, &m->read_high, &readfd, &m->readfd);
/* Normal priority read thead. */
thread_process_fd (m, &m->read, &readfd, &m->readfd);
/* Write thead. */
thread_process_fd (m, &m->write, &writefd, &m->writefd);
}
/* Low priority events. */
if ((thread = thread_trim_head (&m->event_low)) != NULL)
thread_enqueue_low (m, thread);
return NULL;
}