osd-contiki/core/net/rpl/rpl-timers.c
2011-03-17 20:21:56 +01:00

234 lines
7.5 KiB
C

/**
* \addtogroup uip6
* @{
*/
/*
* 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>
*/
#include "contiki-conf.h"
#include "net/rpl/rpl-private.h"
#include "lib/random.h"
#include "sys/ctimer.h"
#define DEBUG DEBUG_NONE
#include "net/uip-debug.h"
/************************************************************************/
static struct ctimer periodic_timer;
static void handle_periodic_timer(void *ptr);
static void new_dio_interval(rpl_dag_t *dag);
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_routes();
rpl_recalculate_ranks();
/* handle DIS */
#ifdef RPL_DIS_SEND
next_dis++;
if(rpl_get_dag(RPL_ANY_INSTANCE) == NULL && next_dis >= RPL_DIS_INTERVAL) {
next_dis = 0;
dis_output(NULL);
}
#endif
ctimer_reset(&periodic_timer);
}
/************************************************************************/
static void
new_dio_interval(rpl_dag_t *dag)
{
uint32_t time;
/* TODO: too small timer intervals for many cases */
time = 1UL << dag->dio_intcurrent;
/* Convert from milliseconds to CLOCK_TICKS. */
time = (time * CLOCK_SECOND) / 1000;
dag->dio_next_delay = time;
/* random number between I/2 and I */
time = time >> 1;
time += (time * 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.
*/
dag->dio_next_delay -= time;
dag->dio_send = 1;
#if RPL_CONF_STATS
/* keep some stats */
dag->dio_totint++;
dag->dio_totrecv += dag->dio_counter;
ANNOTATE("#A rank=%u.%u(%u),stats=%d %d %d %d,color=%s\n",
DAG_RANK(dag->rank, dag),
(10 * (dag->rank % dag->min_hoprankinc)) / dag->min_hoprankinc,
dag->version,
dag->dio_totint, dag->dio_totsend,
dag->dio_totrecv,dag->dio_intcurrent,
dag->rank == ROOT_RANK(dag) ? "BLUE" : "ORANGE");
#endif /* RPL_CONF_STATS */
/* reset the redundancy counter */
dag->dio_counter = 0;
/* schedule the timer */
PRINTF("RPL: Scheduling DIO timer %lu ticks in future (Interval)\n", time);
ctimer_set(&dag->dio_timer, time, &handle_dio_timer, dag);
}
/************************************************************************/
static void
handle_dio_timer(void *ptr)
{
rpl_dag_t *dag;
dag = (rpl_dag_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(&dag->dio_timer, CLOCK_SECOND, &handle_dio_timer, dag);
return;
}
}
if(dag->dio_send) {
/* send DIO if counter is less than desired redundancy */
if(dag->dio_counter < dag->dio_redundancy) {
#if RPL_CONF_STATS
dag->dio_totsend++;
#endif /* RPL_CONF_STATS */
dio_output(dag, NULL);
} else {
PRINTF("RPL: Supressing DIO transmission (%d >= %d)\n",
dag->dio_counter, dag->dio_redundancy);
}
dag->dio_send = 0;
PRINTF("RPL: Scheduling DIO timer %u ticks in future (sent)\n",
dag->dio_next_delay);
ctimer_set(&dag->dio_timer, dag->dio_next_delay, handle_dio_timer, dag);
} else {
/* check if we need to double interval */
if(dag->dio_intcurrent < dag->dio_intmin + dag->dio_intdoubl) {
dag->dio_intcurrent++;
PRINTF("RPL: DIO Timer interval doubled %d\n", dag->dio_intcurrent);
}
new_dio_interval(dag);
}
}
/************************************************************************/
void
rpl_reset_periodic_timer(void)
{
next_dis = RPL_DIS_INTERVAL - RPL_DIS_START_DELAY;
ctimer_set(&periodic_timer, CLOCK_SECOND, handle_periodic_timer, NULL);
}
/************************************************************************/
/* Resets the DIO timer in the DAG to its minimal interval. */
void
rpl_reset_dio_timer(rpl_dag_t *dag, uint8_t force)
{
/* only reset if not just reset or started */
if(force || dag->dio_intcurrent > dag->dio_intmin) {
dag->dio_counter = 0;
dag->dio_intcurrent = dag->dio_intmin;
new_dio_interval(dag);
}
#if RPL_CONF_STATS
rpl_stats.resets++;
#endif
}
/************************************************************************/
static void
handle_dao_timer(void *ptr)
{
rpl_dag_t *dag;
dag = (rpl_dag_t *)ptr;
if (!dio_send_ok && uip_ds6_get_link_local(ADDR_PREFERRED) == NULL) {
PRINTF("RPL: Postpone DAO transmission... \n");
ctimer_set(&dag->dao_timer, CLOCK_SECOND, handle_dao_timer, dag);
return;
}
/* Send the DAO to the best parent. rpl-07 section C.2 lists the
fan-out as being under investigation. */
if(dag->preferred_parent != NULL) {
PRINTF("RPL: handle_dao_timer - sending DAO\n");
/* set time to maxtime */
dao_output(dag->preferred_parent, dag->lifetime_unit * 0xffUL);
} else {
PRINTF("RPL: Could not find a parent to send a DAO to \n");
}
ctimer_stop(&dag->dao_timer);
}
/************************************************************************/
void
rpl_schedule_dao(rpl_dag_t *dag)
{
clock_time_t expiration_time;
expiration_time = etimer_expiration_time(&dag->dao_timer.etimer);
if(!etimer_expired(&dag->dao_timer.etimer)) {
PRINTF("RPL: DAO timer already scheduled\n");
} else {
expiration_time = DEFAULT_DAO_LATENCY / 2 +
(random_rand() % (DEFAULT_DAO_LATENCY));
PRINTF("RPL: Scheduling DAO timer %u ticks in the future\n",
(unsigned)expiration_time);
ctimer_set(&dag->dao_timer, expiration_time,
handle_dao_timer, dag);
}
}
/************************************************************************/