/* Returns the first packet from a neighbor queue */
struct tsch_packet *
tsch_queue_get_packet_for_nbr(const struct tsch_neighbor *n, struct tsch_link *link)
{
if(!tsch_is_locked()) {
int is_shared_link = link != NULL && link->link_options & LINK_OPTION_SHARED;
if(n != NULL) {
int16_t get_index = ringbufindex_peek_get(&n->tx_ringbuf);
if(get_index != -1 &&
!(is_shared_link && !tsch_queue_backoff_expired(n))) { /* If this is a shared link,
make sure the backoff has expired */
#if TSCH_WITH_LINK_SELECTOR
int packet_attr_slotframe = queuebuf_attr(n->tx_array[get_index]->qb, PACKETBUF_ATTR_TSCH_SLOTFRAME);
int packet_attr_timeslot = queuebuf_attr(n->tx_array[get_index]->qb, PACKETBUF_ATTR_TSCH_TIMESLOT);
if(packet_attr_slotframe != 0xffff && packet_attr_slotframe != link->slotframe_handle) {
return NULL;
}
if(packet_attr_timeslot != 0xffff && packet_attr_timeslot != link->timeslot) {
return NULL;
}
#endif
return n->tx_array[get_index];
}
}
}
return NULL;
}
/* Prints out the current schedule (all slotframes and links) */
void
tsch_schedule_print(void)
{
if(!tsch_is_locked()) {
struct tsch_slotframe *sf = list_head(slotframe_list);
printf("Schedule: slotframe list\n");
while(sf != NULL) {
struct tsch_link *l = list_head(sf->links_list);
printf("[Slotframe] Handle %u, size %u\n", sf->handle, sf->size.val);
printf("List of links:\n");
while(l != NULL) {
printf("[Link] Options %02x, type %u, timeslot %u, channel offset %u, address %u\n",
l->link_options, l->link_type, l->timeslot, l->channel_offset, l->addr.u8[7]);
l = list_item_next(l);
}
sf = list_item_next(sf);
}
printf("Schedule: end of slotframe list\n");
}
}
/* Returns the head packet from a neighbor queue (from neighbor address) */
struct tsch_packet *
tsch_queue_get_packet_for_dest_addr(const linkaddr_t *addr, struct tsch_link *link)
{
if(!tsch_is_locked()) {
return tsch_queue_get_packet_for_nbr(tsch_queue_get_nbr(addr), link);
}
return NULL;
}
/* Returns the number of packets currently in the queue */
int
tsch_queue_packet_count(const linkaddr_t *addr)
{
struct tsch_neighbor *n = NULL;
if(!tsch_is_locked()) {
n = tsch_queue_add_nbr(addr);
if(n != NULL) {
return ringbufindex_elements(&n->tx_ringbuf);
}
}
return -1;
}
/* Flush all neighbor queues */
void
tsch_queue_flush_all(void)
{
/* Deallocate unneeded neighbors */
if(!tsch_is_locked()) {
struct tsch_neighbor *n = list_head(neighbor_list);
while(n != NULL) {
struct tsch_neighbor *next_n = list_item_next(n);
tsch_queue_flush_nbr_queue(n);
n = next_n;
}
}
}
/* Get a TSCH time source (we currently assume there is only one) */
struct tsch_neighbor *
tsch_queue_get_time_source(void)
{
if(!tsch_is_locked()) {
struct tsch_neighbor *curr_nbr = list_head(neighbor_list);
while(curr_nbr != NULL) {
if(curr_nbr->is_time_source) {
return curr_nbr;
}
curr_nbr = list_item_next(curr_nbr);
}
}
return NULL;
}
/* Get a TSCH neighbor */
struct tsch_neighbor *
tsch_queue_get_nbr(const linkaddr_t *addr)
{
if(!tsch_is_locked()) {
struct tsch_neighbor *n = list_head(neighbor_list);
while(n != NULL) {
if(linkaddr_cmp(&n->addr, addr)) {
return n;
}
n = list_item_next(n);
}
}
return NULL;
}
/* Looks for a slotframe from a handle */
struct tsch_slotframe *
tsch_schedule_get_slotframe_by_handle(uint16_t handle)
{
if(!tsch_is_locked()) {
struct tsch_slotframe *sf = list_head(slotframe_list);
while(sf != NULL) {
if(sf->handle == handle) {
return sf;
}
sf = list_item_next(sf);
}
}
return NULL;
}
/* Add packet to neighbor queue. Use same lockfree implementation as ringbuf.c (put is atomic) */
struct tsch_packet *
tsch_queue_add_packet(const linkaddr_t *addr, mac_callback_t sent, void *ptr)
{
struct tsch_neighbor *n = NULL;
int16_t put_index = -1;
struct tsch_packet *p = NULL;
if(!tsch_is_locked()) {
n = tsch_queue_add_nbr(addr);
if(n != NULL) {
put_index = ringbufindex_peek_put(&n->tx_ringbuf);
if(put_index != -1) {
p = memb_alloc(&packet_memb);
if(p != NULL) {
/* Enqueue packet */
#ifdef TSCH_CALLBACK_PACKET_READY
TSCH_CALLBACK_PACKET_READY();
#endif
p->qb = queuebuf_new_from_packetbuf();
if(p->qb != NULL) {
p->sent = sent;
p->ptr = ptr;
p->ret = MAC_TX_DEFERRED;
p->transmissions = 0;
/* Add to ringbuf (actual add committed through atomic operation) */
n->tx_array[put_index] = p;
ringbufindex_put(&n->tx_ringbuf);
return p;
} else {
memb_free(&packet_memb, p);
}
}
}
}
}
PRINTF("TSCH-queue:! add packet failed: %u %p %d %p %p\n", tsch_is_locked(), n, put_index, p, p ? p->qb : NULL);
return 0;
}
/* Decrement backoff window for all queues directed at dest_addr */
void
tsch_queue_update_all_backoff_windows(const linkaddr_t *dest_addr)
{
if(!tsch_is_locked()) {
int is_broadcast = linkaddr_cmp(dest_addr, &tsch_broadcast_address);
struct tsch_neighbor *n = list_head(neighbor_list);
while(n != NULL) {
if(n->backoff_window != 0 /* Is the queue in backoff state? */
&& ((n->tx_links_count == 0 && is_broadcast)
|| (n->tx_links_count > 0 && linkaddr_cmp(dest_addr, &n->addr)))) {
n->backoff_window--;
}
n = list_item_next(n);
}
}
}
/* Flush all neighbor queues */
void
tsch_queue_reset(void)
{
/* Deallocate unneeded neighbors */
if(!tsch_is_locked()) {
struct tsch_neighbor *n = list_head(neighbor_list);
while(n != NULL) {
struct tsch_neighbor *next_n = list_item_next(n);
/* Flush queue */
tsch_queue_flush_nbr_queue(n);
/* Reset backoff exponent */
tsch_queue_backoff_reset(n);
n = next_n;
}
}
}
/* Remove first packet from a neighbor queue */
struct tsch_packet *
tsch_queue_remove_packet_from_queue(struct tsch_neighbor *n)
{
if(!tsch_is_locked()) {
if(n != NULL) {
/* Get and remove packet from ringbuf (remove committed through an atomic operation */
int16_t get_index = ringbufindex_get(&n->tx_ringbuf);
if(get_index != -1) {
return n->tx_array[get_index];
} else {
return NULL;
}
}
}
return NULL;
}
/* Update TSCH time source */
int
tsch_queue_update_time_source(const linkaddr_t *new_addr)
{
if(!tsch_is_locked()) {
if(!tsch_is_coordinator) {
struct tsch_neighbor *old_time_src = tsch_queue_get_time_source();
struct tsch_neighbor *new_time_src = NULL;
if(new_addr != NULL) {
/* Get/add neighbor, return 0 in case of failure */
new_time_src = tsch_queue_add_nbr(new_addr);
if(new_time_src == NULL) {
return 0;
}
}
if(new_time_src != old_time_src) {
PRINTF("TSCH: update time source: %u -> %u\n",
TSCH_LOG_ID_FROM_LINKADDR(old_time_src ? &old_time_src->addr : NULL),
TSCH_LOG_ID_FROM_LINKADDR(new_time_src ? &new_time_src->addr : NULL));
/* Update time source */
if(new_time_src != NULL) {
new_time_src->is_time_source = 1;
/* (Re)set keep-alive timeout */
tsch_set_ka_timeout(TSCH_KEEPALIVE_TIMEOUT);
/* Start sending keepalives */
tsch_schedule_keepalive();
} else {
/* Stop sending keepalives */
tsch_set_ka_timeout(0);
}
if(old_time_src != NULL) {
old_time_src->is_time_source = 0;
}
#ifdef TSCH_CALLBACK_NEW_TIME_SOURCE
TSCH_CALLBACK_NEW_TIME_SOURCE(old_time_src, new_time_src);
#endif
}
return 1;
}
}
return 0;
}
/* Looks within a slotframe for a link with a given timeslot */
struct tsch_link *
tsch_schedule_get_link_by_timeslot(struct tsch_slotframe *slotframe, uint16_t timeslot)
{
if(!tsch_is_locked()) {
if(slotframe != NULL) {
struct tsch_link *l = list_head(slotframe->links_list);
/* Loop over all items. Assume there is max one link per timeslot */
while(l != NULL) {
if(l->timeslot == timeslot) {
return l;
}
l = list_item_next(l);
}
return l;
}
}
return NULL;
}
/* Deallocate neighbors with empty queue */
void
tsch_queue_free_unused_neighbors(void)
{
/* Deallocate unneeded neighbors */
if(!tsch_is_locked()) {
struct tsch_neighbor *n = list_head(neighbor_list);
while(n != NULL) {
struct tsch_neighbor *next_n = list_item_next(n);
/* Queue is empty, no tx link to this neighbor: deallocate.
* Always keep time source and virtual broadcast neighbors. */
if(!n->is_broadcast && !n->is_time_source && !n->tx_links_count
&& tsch_queue_is_empty(n)) {
tsch_queue_remove_nbr(n);
}
n = next_n;
}
}
}
/* Looks for a link from a handle */
struct tsch_link *
tsch_schedule_get_link_by_handle(uint16_t handle)
{
if(!tsch_is_locked()) {
struct tsch_slotframe *sf = list_head(slotframe_list);
while(sf != NULL) {
struct tsch_link *l = list_head(sf->links_list);
/* Loop over all items. Assume there is max one link per timeslot */
while(l != NULL) {
if(l->handle == handle) {
return l;
}
l = list_item_next(l);
}
sf = list_item_next(sf);
}
}
return NULL;
}
/* Update TSCH time source */
int
tsch_queue_update_time_source(const linkaddr_t *new_addr)
{
if(!tsch_is_locked()) {
if(!tsch_is_coordinator) {
struct tsch_neighbor *old_time_src = tsch_queue_get_time_source();
struct tsch_neighbor *new_time_src = NULL;
if(new_addr != NULL) {
/* Get/add neighbor, return 0 in case of failure */
new_time_src = tsch_queue_add_nbr(new_addr);
if(new_time_src == NULL) {
return 0;
}
}
if(new_time_src != old_time_src) {
PRINTF("TSCH: update time source: %u -> %u\n",
TSCH_LOG_ID_FROM_LINKADDR(old_time_src ? &old_time_src->addr : NULL),
TSCH_LOG_ID_FROM_LINKADDR(new_time_src ? &new_time_src->addr : NULL));
/* Update time source */
if(new_time_src != NULL) {
new_time_src->is_time_source = 1;
}
if(old_time_src != NULL) {
old_time_src->is_time_source = 0;
}
#ifdef TSCH_CALLBACK_NEW_TIME_SOURCE
TSCH_CALLBACK_NEW_TIME_SOURCE(old_time_src, new_time_src);
#endif
}
return 1;
}
}
return 0;
}
/* Returns the head packet of any neighbor queue with zero backoff counter.
* Writes pointer to the neighbor in *n */
struct tsch_packet *
tsch_queue_get_unicast_packet_for_any(struct tsch_neighbor **n, struct tsch_link *link)
{
if(!tsch_is_locked()) {
struct tsch_neighbor *curr_nbr = list_head(neighbor_list);
struct tsch_packet *p = NULL;
while(curr_nbr != NULL) {
if(!curr_nbr->is_broadcast && curr_nbr->tx_links_count == 0) {
/* Only look up for non-broadcast neighbors we do not have a tx link to */
p = tsch_queue_get_packet_for_nbr(curr_nbr, link);
if(p != NULL) {
if(n != NULL) {
*n = curr_nbr;
}
return p;
}
}
curr_nbr = list_item_next(curr_nbr);
}
}
return NULL;
}
/* Is the neighbor queue empty? */
int
tsch_queue_is_empty(const struct tsch_neighbor *n)
{
return !tsch_is_locked() && n != NULL && ringbufindex_empty(&n->tx_ringbuf);
}
/* Returns the next active link after a given ASN, and a backup link (for the same ASN, with Rx flag) */
struct tsch_link *
tsch_schedule_get_next_active_link(struct asn_t *asn, uint16_t *time_offset,
struct tsch_link **backup_link)
{
uint16_t time_to_curr_best = 0;
struct tsch_link *curr_best = NULL;
struct tsch_link *curr_backup = NULL; /* Keep a back link in case the current link
turns out useless when the time comes. For instance, for a Tx-only link, if there is
no outgoing packet in queue. In that case, run the backup link instead. The backup link
must have Rx flag set. */
if(!tsch_is_locked()) {
struct tsch_slotframe *sf = list_head(slotframe_list);
/* For each slotframe, look for the earliest occurring link */
while(sf != NULL) {
/* Get timeslot from ASN, given the slotframe length */
uint16_t timeslot = ASN_MOD(*asn, sf->size);
struct tsch_link *l = list_head(sf->links_list);
while(l != NULL) {
uint16_t time_to_timeslot =
l->timeslot > timeslot ?
l->timeslot - timeslot :
sf->size.val + l->timeslot - timeslot;
if(curr_best == NULL || time_to_timeslot < time_to_curr_best) {
time_to_curr_best = time_to_timeslot;
curr_best = l;
curr_backup = NULL;
} else if(time_to_timeslot == time_to_curr_best) {
struct tsch_link *new_best = NULL;
/* Two links are overlapping, we need to select one of them.
* By standard: prioritize Tx links first, second by lowest handle */
if((curr_best->link_options & LINK_OPTION_TX) == (l->link_options & LINK_OPTION_TX)) {
/* Both or neither links have Tx, select the one with lowest handle */
if(l->slotframe_handle < curr_best->slotframe_handle) {
new_best = l;
}
} else {
/* Select the link that has the Tx option */
if(l->link_options & LINK_OPTION_TX) {
new_best = l;
}
}
/* Maintain backup_link */
if(curr_backup == NULL) {
/* Check if 'l' best can be used as backup */
if(new_best != l && (l->link_options & LINK_OPTION_RX)) { /* Does 'l' have Rx flag? */
curr_backup = l;
}
/* Check if curr_best can be used as backup */
if(new_best != curr_best && (curr_best->link_options & LINK_OPTION_RX)) { /* Does curr_best have Rx flag? */
curr_backup = curr_best;
}
}
/* Maintain curr_best */
if(new_best != NULL) {
curr_best = new_best;
}
}
l = list_item_next(l);
}
sf = list_item_next(sf);
}
if(time_offset != NULL) {
*time_offset = time_to_curr_best;
}
}
if(backup_link != NULL) {
*backup_link = curr_backup;
}
return curr_best;
}
