/* * Copyright (c) 2010, Swedish Institute of Computer Science. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * This file is part of the Contiki operating system. */ /** * \file * RPL timer management. * * \author Joakim Eriksson , Nicolas Tsiftes */ /** * \addtogroup uip6 * @{ */ #include "contiki-conf.h" #include "net/rpl/rpl-private.h" #include "net/rpl/rpl-ns.h" #include "net/link-stats.h" #include "net/ipv6/multicast/uip-mcast6.h" #include "lib/random.h" #include "sys/ctimer.h" #define DEBUG DEBUG_NONE #include "net/ip/uip-debug.h" /* A configurable function called after update of the RPL DIO interval */ #ifdef RPL_CALLBACK_NEW_DIO_INTERVAL void RPL_CALLBACK_NEW_DIO_INTERVAL(uint8_t dio_interval); #endif /* RPL_CALLBACK_NEW_DIO_INTERVAL */ #ifdef RPL_PROBING_SELECT_FUNC rpl_parent_t *RPL_PROBING_SELECT_FUNC(rpl_dag_t *dag); #endif /* RPL_PROBING_SELECT_FUNC */ #ifdef RPL_PROBING_DELAY_FUNC clock_time_t RPL_PROBING_DELAY_FUNC(rpl_dag_t *dag); #endif /* RPL_PROBING_DELAY_FUNC */ /*---------------------------------------------------------------------------*/ static struct ctimer periodic_timer; static void handle_periodic_timer(void *ptr); static void new_dio_interval(rpl_instance_t *instance); static void handle_dio_timer(void *ptr); static uint16_t next_dis; /* dio_send_ok is true if the node is ready to send DIOs */ static uint8_t dio_send_ok; /*---------------------------------------------------------------------------*/ static void handle_periodic_timer(void *ptr) { rpl_dag_t *dag = rpl_get_any_dag(); rpl_purge_dags(); if(dag != NULL) { if(RPL_IS_STORING(dag->instance)) { rpl_purge_routes(); } if(RPL_IS_NON_STORING(dag->instance)) { rpl_ns_periodic(); } } rpl_recalculate_ranks(); /* handle DIS */ #if RPL_DIS_SEND next_dis++; if(dag == NULL && next_dis >= RPL_DIS_INTERVAL) { next_dis = 0; dis_output(NULL); } #endif ctimer_reset(&periodic_timer); } /*---------------------------------------------------------------------------*/ static void new_dio_interval(rpl_instance_t *instance) { uint32_t time; clock_time_t ticks; /* TODO: too small timer intervals for many cases */ time = 1UL << instance->dio_intcurrent; /* Convert from milliseconds to CLOCK_TICKS. */ ticks = (time * CLOCK_SECOND) / 1000; instance->dio_next_delay = ticks; /* random number between I/2 and I */ ticks = ticks / 2 + (ticks / 2 * (uint32_t)random_rand()) / RANDOM_RAND_MAX; /* * The intervals must be equally long among the nodes for Trickle to * operate efficiently. Therefore we need to calculate the delay between * the randomized time and the start time of the next interval. */ instance->dio_next_delay -= ticks; instance->dio_send = 1; #if RPL_CONF_STATS /* keep some stats */ instance->dio_totint++; instance->dio_totrecv += instance->dio_counter; ANNOTATE("#A rank=%u.%u(%u),stats=%d %d %d %d,color=%s\n", DAG_RANK(instance->current_dag->rank, instance), (10 * (instance->current_dag->rank % instance->min_hoprankinc)) / instance->min_hoprankinc, instance->current_dag->version, instance->dio_totint, instance->dio_totsend, instance->dio_totrecv,instance->dio_intcurrent, instance->current_dag->rank == ROOT_RANK(instance) ? "BLUE" : "ORANGE"); #endif /* RPL_CONF_STATS */ /* reset the redundancy counter */ instance->dio_counter = 0; /* schedule the timer */ PRINTF("RPL: Scheduling DIO timer %lu ticks in future (Interval)\n", ticks); ctimer_set(&instance->dio_timer, ticks, &handle_dio_timer, instance); #ifdef RPL_CALLBACK_NEW_DIO_INTERVAL RPL_CALLBACK_NEW_DIO_INTERVAL(instance->dio_intcurrent); #endif /* RPL_CALLBACK_NEW_DIO_INTERVAL */ } /*---------------------------------------------------------------------------*/ static void handle_dio_timer(void *ptr) { rpl_instance_t *instance; instance = (rpl_instance_t *)ptr; PRINTF("RPL: DIO Timer triggered\n"); if(!dio_send_ok) { if(uip_ds6_get_link_local(ADDR_PREFERRED) != NULL) { dio_send_ok = 1; } else { PRINTF("RPL: Postponing DIO transmission since link local address is not ok\n"); ctimer_set(&instance->dio_timer, CLOCK_SECOND, &handle_dio_timer, instance); return; } } if(instance->dio_send) { /* send DIO if counter is less than desired redundancy */ if(instance->dio_redundancy == 0 || instance->dio_counter < instance->dio_redundancy) { #if RPL_CONF_STATS instance->dio_totsend++; #endif /* RPL_CONF_STATS */ dio_output(instance, NULL); } else { PRINTF("RPL: Suppressing DIO transmission (%d >= %d)\n", instance->dio_counter, instance->dio_redundancy); } instance->dio_send = 0; PRINTF("RPL: Scheduling DIO timer %lu ticks in future (sent)\n", instance->dio_next_delay); ctimer_set(&instance->dio_timer, instance->dio_next_delay, handle_dio_timer, instance); } else { /* check if we need to double interval */ if(instance->dio_intcurrent < instance->dio_intmin + instance->dio_intdoubl) { instance->dio_intcurrent++; PRINTF("RPL: DIO Timer interval doubled %d\n", instance->dio_intcurrent); } new_dio_interval(instance); } #if DEBUG rpl_print_neighbor_list(); #endif } /*---------------------------------------------------------------------------*/ void rpl_reset_periodic_timer(void) { next_dis = RPL_DIS_INTERVAL / 2 + ((uint32_t)RPL_DIS_INTERVAL * (uint32_t)random_rand()) / RANDOM_RAND_MAX - RPL_DIS_START_DELAY; ctimer_set(&periodic_timer, CLOCK_SECOND, handle_periodic_timer, NULL); } /*---------------------------------------------------------------------------*/ /* Resets the DIO timer in the instance to its minimal interval. */ void rpl_reset_dio_timer(rpl_instance_t *instance) { #if !RPL_LEAF_ONLY /* Do not reset if we are already on the minimum interval, unless forced to do so. */ if(instance->dio_intcurrent > instance->dio_intmin) { instance->dio_counter = 0; instance->dio_intcurrent = instance->dio_intmin; new_dio_interval(instance); } #if RPL_CONF_STATS rpl_stats.resets++; #endif /* RPL_CONF_STATS */ #endif /* RPL_LEAF_ONLY */ } /*---------------------------------------------------------------------------*/ static void handle_dao_timer(void *ptr); static void set_dao_lifetime_timer(rpl_instance_t *instance) { if(rpl_get_mode() == RPL_MODE_FEATHER) { return; } /* Set up another DAO within half the expiration time, if such a time has been configured */ if(instance->default_lifetime != RPL_INFINITE_LIFETIME) { clock_time_t expiration_time; expiration_time = (clock_time_t)instance->default_lifetime * (clock_time_t)instance->lifetime_unit * CLOCK_SECOND / 2; /* make the time for the re registration be betwen 1/2 - 3/4 of lifetime */ expiration_time = expiration_time + (random_rand() % (expiration_time / 2)); PRINTF("RPL: Scheduling DAO lifetime timer %u ticks in the future\n", (unsigned)expiration_time); ctimer_set(&instance->dao_lifetime_timer, expiration_time, handle_dao_timer, instance); } } /*---------------------------------------------------------------------------*/ static void handle_dao_timer(void *ptr) { rpl_instance_t *instance; #if RPL_WITH_MULTICAST uip_mcast6_route_t *mcast_route; uint8_t i; #endif instance = (rpl_instance_t *)ptr; if(!dio_send_ok && uip_ds6_get_link_local(ADDR_PREFERRED) == NULL) { PRINTF("RPL: Postpone DAO transmission\n"); ctimer_set(&instance->dao_timer, CLOCK_SECOND, handle_dao_timer, instance); return; } /* Send the DAO to the DAO parent set -- the preferred parent in our case. */ if(instance->current_dag->preferred_parent != NULL) { PRINTF("RPL: handle_dao_timer - sending DAO\n"); /* Set the route lifetime to the default value. */ dao_output(instance->current_dag->preferred_parent, instance->default_lifetime); #if RPL_WITH_MULTICAST /* Send DAOs for multicast prefixes only if the instance is in MOP 3 */ if(instance->mop == RPL_MOP_STORING_MULTICAST) { /* Send a DAO for own multicast addresses */ for(i = 0; i < UIP_DS6_MADDR_NB; i++) { if(uip_ds6_if.maddr_list[i].isused && uip_is_addr_mcast_global(&uip_ds6_if.maddr_list[i].ipaddr)) { dao_output_target(instance->current_dag->preferred_parent, &uip_ds6_if.maddr_list[i].ipaddr, RPL_MCAST_LIFETIME); } } /* Iterate over multicast routes and send DAOs */ mcast_route = uip_mcast6_route_list_head(); while(mcast_route != NULL) { /* Don't send if it's also our own address, done that already */ if(uip_ds6_maddr_lookup(&mcast_route->group) == NULL) { dao_output_target(instance->current_dag->preferred_parent, &mcast_route->group, RPL_MCAST_LIFETIME); } mcast_route = list_item_next(mcast_route); } } #endif } else { PRINTF("RPL: No suitable DAO parent\n"); } ctimer_stop(&instance->dao_timer); if(etimer_expired(&instance->dao_lifetime_timer.etimer)) { set_dao_lifetime_timer(instance); } } /*---------------------------------------------------------------------------*/ static void schedule_dao(rpl_instance_t *instance, clock_time_t latency) { clock_time_t expiration_time; if(rpl_get_mode() == RPL_MODE_FEATHER) { return; } expiration_time = etimer_expiration_time(&instance->dao_timer.etimer); if(!etimer_expired(&instance->dao_timer.etimer)) { PRINTF("RPL: DAO timer already scheduled\n"); } else { if(latency != 0) { expiration_time = latency / 2 + (random_rand() % (latency)); } else { expiration_time = 0; } PRINTF("RPL: Scheduling DAO timer %u ticks in the future\n", (unsigned)expiration_time); ctimer_set(&instance->dao_timer, expiration_time, handle_dao_timer, instance); set_dao_lifetime_timer(instance); } } /*---------------------------------------------------------------------------*/ void rpl_schedule_dao(rpl_instance_t *instance) { schedule_dao(instance, RPL_DAO_DELAY); } /*---------------------------------------------------------------------------*/ void rpl_schedule_dao_immediately(rpl_instance_t *instance) { schedule_dao(instance, 0); } /*---------------------------------------------------------------------------*/ void rpl_cancel_dao(rpl_instance_t *instance) { ctimer_stop(&instance->dao_timer); ctimer_stop(&instance->dao_lifetime_timer); } /*---------------------------------------------------------------------------*/ static void handle_unicast_dio_timer(void *ptr) { rpl_instance_t *instance = (rpl_instance_t *)ptr; uip_ipaddr_t *target_ipaddr = rpl_get_parent_ipaddr(instance->unicast_dio_target); if(target_ipaddr != NULL) { dio_output(instance, target_ipaddr); } } /*---------------------------------------------------------------------------*/ void rpl_schedule_unicast_dio_immediately(rpl_instance_t *instance) { ctimer_set(&instance->unicast_dio_timer, 0, handle_unicast_dio_timer, instance); } /*---------------------------------------------------------------------------*/ #if RPL_WITH_PROBING clock_time_t get_probing_delay(rpl_dag_t *dag) { if(dag != NULL && dag->instance != NULL && dag->instance->urgent_probing_target != NULL) { /* Urgent probing needed (to find out if a neighbor may become preferred parent) */ return random_rand() % (CLOCK_SECOND * 10); } else { /* Else, use normal probing interval */ return ((RPL_PROBING_INTERVAL) / 2) + random_rand() % (RPL_PROBING_INTERVAL); } } /*---------------------------------------------------------------------------*/ rpl_parent_t * get_probing_target(rpl_dag_t *dag) { /* Returns the next probing target. The current implementation probes the urgent * probing target if any, or the preferred parent if its link statistics need refresh. * Otherwise, it picks at random between: * (1) selecting the best parent with non-fresh link statistics * (2) selecting the least recently updated parent */ rpl_parent_t *p; rpl_parent_t *probing_target = NULL; rpl_rank_t probing_target_rank = INFINITE_RANK; clock_time_t probing_target_age = 0; clock_time_t clock_now = clock_time(); if(dag == NULL || dag->instance == NULL) { return NULL; } /* There is an urgent probing target */ if(dag->instance->urgent_probing_target != NULL) { return dag->instance->urgent_probing_target; } /* The preferred parent needs probing */ if(dag->preferred_parent != NULL && !rpl_parent_is_fresh(dag->preferred_parent)) { return dag->preferred_parent; } /* With 50% probability: probe best non-fresh parent */ if(random_rand() % 2 == 0) { p = nbr_table_head(rpl_parents); while(p != NULL) { if(p->dag == dag && !rpl_parent_is_fresh(p)) { /* p is in our dag and needs probing */ rpl_rank_t p_rank = rpl_rank_via_parent(p); if(probing_target == NULL || p_rank < probing_target_rank) { probing_target = p; probing_target_rank = p_rank; } } p = nbr_table_next(rpl_parents, p); } } /* If we still do not have a probing target: pick the least recently updated parent */ if(probing_target == NULL) { p = nbr_table_head(rpl_parents); while(p != NULL) { const struct link_stats *stats =rpl_get_parent_link_stats(p); if(p->dag == dag && stats != NULL) { if(probing_target == NULL || clock_now - stats->last_tx_time > probing_target_age) { probing_target = p; probing_target_age = clock_now - stats->last_tx_time; } } 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); uip_ipaddr_t *target_ipaddr = rpl_get_parent_ipaddr(probing_target); /* Perform probing */ if(target_ipaddr != NULL) { const struct link_stats *stats = rpl_get_parent_link_stats(probing_target); (void)stats; PRINTF("RPL: probing %u %s last tx %u min ago\n", rpl_get_parent_lladdr(probing_target)->u8[7], instance->urgent_probing_target != NULL ? "(urgent)" : "", probing_target != NULL ? (unsigned)((clock_time() - stats->last_tx_time) / (60 * CLOCK_SECOND)) : 0 ); /* Send probe, e.g. unicast DIO or DIS */ RPL_PROBING_SEND_FUNC(instance, target_ipaddr); instance->urgent_probing_target = NULL; } /* Schedule next probing */ rpl_schedule_probing(instance); #if DEBUG rpl_print_neighbor_list(); #endif } /*---------------------------------------------------------------------------*/ void rpl_schedule_probing(rpl_instance_t *instance) { ctimer_set(&instance->probing_timer, RPL_PROBING_DELAY_FUNC(instance->current_dag), handle_probing_timer, instance); } #endif /* RPL_WITH_PROBING */ /** @}*/