Implement RPL probing

This commit is contained in:
Simon Duquennoy 2015-05-06 11:35:42 +02:00
parent 529376be77
commit 47ba4c0c4b
7 changed files with 155 additions and 6 deletions

View file

@ -207,4 +207,46 @@
#define RPL_INSERT_HBH_OPTION 1
#endif
/*
* RPL probing. When enabled, probes will be sent periodically to keep
* parent link estimates up to date.
* */
#ifdef RPL_CONF_WITH_PROBING
#define RPL_WITH_PROBING RPL_CONF_WITH_PROBING
#else
#define RPL_WITH_PROBING 1
#endif
/*
* RPL probing interval.
* */
#ifdef RPL_CONF_PROBING_INTERVAL
#define RPL_PROBING_INTERVAL RPL_CONF_PROBING_INTERVAL
#else
#define RPL_PROBING_INTERVAL (120 * CLOCK_SECOND)
#endif
/*
* Function used to select the next parent to be probed.
* */
#ifdef RPL_CONF_PROBING_SELECT_FUNC
#define RPL_PROBING_SELECT_FUNC RPL_CONF_PROBING_SELECT_FUNC
#else
#define RPL_PROBING_SELECT_FUNC(dag) get_probing_target((dag))
#endif
/*
* Function used to send RPL probes.
* To probe with DIO, use:
* #define RPL_CONF_PROBING_SEND_FUNC(instance, addr) dio_output((instance), (addr))
* To probe with DIS, use:
* #define RPL_CONF_PROBING_SEND_FUNC(instance, addr) dis_output((addr))
* Any other custom probing function is also acceptable.
* */
#ifdef RPL_CONF_PROBING_SEND_FUNC
#define RPL_PROBING_SEND_FUNC RPL_CONF_PROBING_SEND_FUNC
#else
#define RPL_PROBING_SEND_FUNC(instance, addr) dio_output((instance), (addr))
#endif
#endif /* RPL_CONF_H */

View file

@ -75,7 +75,7 @@ static rpl_of_t * const objective_functions[] = {&RPL_OF};
/*---------------------------------------------------------------------------*/
/* Per-parent RPL information */
NBR_TABLE(rpl_parent_t, rpl_parents);
NBR_TABLE_GLOBAL(rpl_parent_t, rpl_parents);
/*---------------------------------------------------------------------------*/
/* Allocate instance table. */
rpl_instance_t instance_table[RPL_MAX_INSTANCES];
@ -90,14 +90,17 @@ rpl_print_neighbor_list()
int curr_dio_interval = default_instance->dio_intcurrent;
int curr_rank = default_instance->current_dag->rank;
rpl_parent_t *p = nbr_table_head(rpl_parents);
clock_time_t now = clock_time();
printf("RPL: rank %u dioint %u, %u nbr(s)\n", curr_rank, curr_dio_interval, uip_ds6_nbr_num());
while(p != NULL) {
uip_ds6_nbr_t *nbr = rpl_get_nbr(p);
printf("RPL: nbr %3u %5u, %5u => %5u %c\n",
printf("RPL: nbr %3u %5u, %5u => %5u %c (last tx %u min ago)\n",
nbr_table_get_lladdr(rpl_parents, p)->u8[7],
p->rank, nbr ? nbr->link_metric : 0, default_instance->of->calculate_rank(p, 0),
p == default_instance->current_dag->preferred_parent ? '*' : ' ');
p->rank, nbr ? nbr->link_metric : 0,
default_instance->of->calculate_rank(p, 0),
p == default_instance->current_dag->preferred_parent ? '*' : ' ',
(now - p->last_tx_time) / (60 * CLOCK_SECOND));
p = nbr_table_next(rpl_parents, p);
}
printf("RPL: end of list\n");
@ -496,6 +499,9 @@ rpl_alloc_instance(uint8_t instance_id)
instance->instance_id = instance_id;
instance->def_route = NULL;
instance->used = 1;
#if RPL_WITH_PROBING
rpl_schedule_probing(instance);
#endif /* RPL_WITH_PROBING */
return instance;
}
}
@ -556,6 +562,9 @@ rpl_free_instance(rpl_instance_t *instance)
rpl_set_default_route(instance, NULL);
#if RPL_WITH_PROBING
ctimer_stop(&instance->probing_timer);
#endif /* RPL_WITH_PROBING */
ctimer_stop(&instance->dio_timer);
ctimer_stop(&instance->dao_timer);
ctimer_stop(&instance->dao_lifetime_timer);

View file

@ -466,8 +466,12 @@ dio_output(rpl_instance_t *instance, uip_ipaddr_t *uc_addr)
buffer[pos++] = instance->dtsn_out;
/* always request new DAO to refresh route */
RPL_LOLLIPOP_INCREMENT(instance->dtsn_out);
if(uc_addr == NULL) {
/* Request new DAO to refresh route. We do not do this for unicast DIO
* in order to avoid DAO messages after a DIS-DIO update,
* or upon unicast DIO probing. */
RPL_LOLLIPOP_INCREMENT(instance->dtsn_out);
}
/* reserved 2 bytes */
buffer[pos++] = 0; /* flags */

View file

@ -313,6 +313,7 @@ rpl_of_t *rpl_find_of(rpl_ocp_t);
void rpl_schedule_dao(rpl_instance_t *);
void rpl_schedule_dao_immediately(rpl_instance_t *);
void rpl_cancel_dao(rpl_instance_t *instance);
void rpl_schedule_probing(rpl_instance_t *instance);
void rpl_reset_dio_timer(rpl_instance_t *);
void rpl_reset_periodic_timer(void);

View file

@ -327,5 +327,90 @@ rpl_cancel_dao(rpl_instance_t *instance)
ctimer_stop(&instance->dao_lifetime_timer);
}
/*---------------------------------------------------------------------------*/
#if RPL_WITH_PROBING
static rpl_parent_t *
get_probing_target(rpl_dag_t *dag)
{
/* Returns the next probing target. The current implementation looks for the
* best parent to which we have not transmitted since 2 * RPL_PROBING_INTERVAL.
* This will mostly select the preferred and second best parents. Probing the
* second best parent is important: if the link is good, RPL might choose to
* switch to it. If the link is bad, the second best parent will decrease in
* ranking, and another parent will be probed next time. */
rpl_parent_t *p;
rpl_parent_t *probing_target;
rpl_rank_t probing_target_rank;
/* Look for a parent we have not sent to since 2 * RPL_PROBING_INTERVAL,
* e.g. with last_tx_time earlier than min_last_tx */
clock_time_t min_last_tx = clock_time();
min_last_tx = min_last_tx > 2 * RPL_PROBING_INTERVAL ? min_last_tx - 2 * RPL_PROBING_INTERVAL : 1;
if(dag == NULL ||
dag->instance == NULL ||
dag->preferred_parent == NULL) {
return NULL;
}
/* Our preferred parent needs probing */
if(dag->preferred_parent->last_tx_time < min_last_tx) {
return dag->preferred_parent;
}
/* Look for the best parent that needs probing. */
probing_target = NULL;
probing_target_rank = INFINITE_RANK;
p = nbr_table_head(rpl_parents);
while(p != NULL) {
if(p->dag == dag && p->last_tx_time < min_last_tx) {
rpl_rank_t p_rank = dag->instance->of->calculate_rank(p, 0);
/* p is in our dag and needs probing */
if(probing_target == NULL) {
probing_target = p;
probing_target_rank = p_rank;
} else {
if(p_rank < probing_target_rank) {
/* Found better candidate */
probing_target = p;
probing_target_rank = p_rank;
}
}
}
p = nbr_table_next(rpl_parents, p);
}
return probing_target;
}
/*---------------------------------------------------------------------------*/
static void
handle_probing_timer(void *ptr)
{
rpl_instance_t *instance = (rpl_instance_t *)ptr;
rpl_parent_t *probing_target = RPL_PROBING_SELECT_FUNC(instance->current_dag);
/* Perform probing */
if(probing_target != NULL && rpl_get_parent_ipaddr(probing_target) != NULL) {
PRINTF("RPL: probing %3u\n",
nbr_table_get_lladdr(rpl_parents, probing_target)->u8[7]);
/* Send probe, e.g. unicast DIO or DIS */
RPL_PROBING_SEND_FUNC(instance, rpl_get_parent_ipaddr(probing_target));
}
/* Schedule next probing */
rpl_schedule_probing(instance);
#if DEBUG
rpl_print_neighbor_list();
#endif
}
/*---------------------------------------------------------------------------*/
void
rpl_schedule_probing(rpl_instance_t *instance)
{
clock_time_t delay = (RPL_PROBING_INTERVAL / 2) +
random_rand() % (RPL_PROBING_INTERVAL / 2);
ctimer_set(&instance->probing_timer, delay,
handle_probing_timer, instance);
}
#endif /* RPL_WITH_PROBING */
/** @}*/

View file

@ -263,6 +263,7 @@ rpl_link_neighbor_callback(const linkaddr_t *addr, int status, int numtx)
parent->flags |= RPL_PARENT_FLAG_UPDATED;
if(instance->of->neighbor_link_callback != NULL) {
instance->of->neighbor_link_callback(parent, status, numtx);
parent->last_tx_time = clock_time();
}
}
}

View file

@ -114,6 +114,7 @@ struct rpl_parent {
rpl_metric_container_t mc;
#endif /* RPL_DAG_MC != RPL_DAG_MC_NONE */
rpl_rank_t rank;
clock_time_t last_tx_time;
uint8_t dtsn;
uint8_t flags;
};
@ -224,6 +225,9 @@ struct rpl_instance {
uint16_t dio_totrecv;
#endif /* RPL_CONF_STATS */
clock_time_t dio_next_delay; /* delay for completion of dio interval */
#if RPL_WITH_PROBING
struct ctimer probing_timer;
#endif /* RPL_WITH_PROBING */
struct ctimer dio_timer;
struct ctimer dao_timer;
struct ctimer dao_lifetime_timer;
@ -253,6 +257,9 @@ void rpl_dag_init(void);
uip_ds6_nbr_t *rpl_get_nbr(rpl_parent_t *parent);
void rpl_print_neighbor_list();
/* Per-parent RPL information */
NBR_TABLE_DECLARE(rpl_parents);
/**
* RPL modes
*