static int update_shortterm(void)
{
if (shortterm_priority_queue_root.first == NULL) {
/* there is no vtimer to schedule, queue is empty */
DEBUG("update_shortterm: shortterm_priority_queue_root.next == NULL - dont know what to do here\n");
return 0;
}
if (hwtimer_id != -1) {
/* there is a running hwtimer for us */
if (hwtimer_next_absolute != shortterm_priority_queue_root.first->priority) {
/* the next timer in the vtimer queue is not the next hwtimer */
/* we have to remove the running hwtimer (and schedule a new one) */
hwtimer_remove(hwtimer_id);
}
else {
/* the next vtimer is the next hwtimer, nothing to do */
return 0;
}
}
/* short term part of the next vtimer */
hwtimer_next_absolute = shortterm_priority_queue_root.first->priority;
uint32_t next = hwtimer_next_absolute;
/* current short term time */
uint32_t now = HWTIMER_TICKS_TO_US(hwtimer_now());
/* make sure the longterm_tick_timer does not get truncated */
if (node_get_timer(shortterm_priority_queue_root.first)->action != vtimer_callback_tick) {
/* the next vtimer to schedule is the long term tick */
/* it has a shortterm offset of longterm_tick_start */
next += longterm_tick_start;
}
if((next - HWTIMER_TICKS_TO_US(VTIMER_THRESHOLD) - now) > MICROSECONDS_PER_TICK ) {
DEBUG("truncating next (next - HWTIMER_TICKS_TO_US(VTIMER_THRESHOLD) - now): %lu\n", (next - HWTIMER_TICKS_TO_US(VTIMER_THRESHOLD) - now));
next = now + HWTIMER_TICKS_TO_US(VTIMER_BACKOFF);
}
DEBUG("update_shortterm: Set hwtimer to %" PRIu32 " (now=%lu)\n", next, HWTIMER_TICKS_TO_US(hwtimer_now()));
hwtimer_id = hwtimer_set_absolute(HWTIMER_TICKS(next), vtimer_callback, NULL);
return 0;
}
static int update_shortterm() {
if (hwtimer_id != -1) {
if (hwtimer_next_absolute != shortterm_queue_root.next->priority) {
hwtimer_remove(hwtimer_id);
} else {
return 0;
}
}
hwtimer_next_absolute = shortterm_queue_root.next->priority;
unsigned int next = hwtimer_next_absolute + longterm_tick_start;
unsigned int now = hwtimer_now();
if((next - VTIMER_THRESHOLD - now) > MICROSECONDS_PER_TICK ) {
next = now + VTIMER_BACKOFF;
}
hwtimer_id = hwtimer_set_absolute(next, vtimer_callback, NULL);
DEBUG("update_shortterm: Set hwtimer to %lu (now=%lu)\n", hwtimer_next_absolute + longterm_tick_start, hwtimer_now());
return 0;
}
