contiki/core/net/rpl/rpl-timers.c
2016-03-09 11:32:24 +01:00

454 lines
15 KiB
C

/*
* 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 <joakime@sics.se>, Nicolas Tsiftes <nvt@sics.se>
*/
/**
* \addtogroup uip6
* @{
*/
#include "contiki-conf.h"
#include "net/rpl/rpl-private.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 */
/*---------------------------------------------------------------------------*/
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_purge_dags();
rpl_purge_routes();
rpl_recalculate_ranks();
/* handle DIS */
#if RPL_DIS_SEND
next_dis++;
if(rpl_get_any_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->lifetime_unit != 0xffff && instance->default_lifetime != 0xff) {
clock_time_t expiration_time;
expiration_time = (clock_time_t)instance->default_lifetime *
(clock_time_t)instance->lifetime_unit *
CLOCK_SECOND / 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_CONF_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_CONF_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
static rpl_parent_t *
get_probing_target(rpl_dag_t *dag)
{
/* Returns the next probing target. The current implementation probes the current
* preferred parent if we have not updated its link for RPL_PROBING_EXPIRATION_TIME.
* Otherwise, it picks at random between:
* (1) selecting the best parent not updated for RPL_PROBING_EXPIRATION_TIME
* (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;
/* min_last_tx is the clock time RPL_PROBING_EXPIRATION_TIME in the past */
clock_time_t min_last_tx = clock_time();
min_last_tx = min_last_tx > 2 * RPL_PROBING_EXPIRATION_TIME
? min_last_tx - RPL_PROBING_EXPIRATION_TIME : 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) {
probing_target = dag->preferred_parent;
}
/* With 50% probability: probe best parent not updated for RPL_PROBING_EXPIRATION_TIME */
if(probing_target == NULL && (random_rand() % 2) == 0) {
p = nbr_table_head(rpl_parents);
while(p != NULL) {
if(p->dag == dag && p->last_tx_time < min_last_tx) {
/* p is in our dag and needs probing */
rpl_rank_t p_rank = dag->instance->of->calculate_rank(p, 0);
if(probing_target == NULL
|| p_rank < probing_target_rank) {
probing_target = p;
probing_target_rank = p_rank;
}
}
p = nbr_table_next(rpl_parents, p);
}
}
/* The default probing target is the least recently updated parent */
if(probing_target == NULL) {
p = nbr_table_head(rpl_parents);
while(p != NULL) {
if(p->dag == dag) {
if(probing_target == NULL
|| p->last_tx_time < probing_target->last_tx_time) {
probing_target = p;
}
}
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) {
PRINTF("RPL: probing %u ((last tx %u min ago))\n",
nbr_table_get_lladdr(rpl_parents, probing_target)->u8[7],
(unsigned)((clock_time() - probing_target->last_tx_time) / (60 * CLOCK_SECOND)));
/* Send probe (unicast DIO or DIS) */
RPL_PROBING_SEND_FUNC(instance, target_ipaddr);
}
/* 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(),
handle_probing_timer, instance);
}
#endif /* RPL_WITH_PROBING */
/** @}*/