Rewrote parts of the retransmission logic so that collect is robust against the situation where the MAC layer will fail to callback after a packet has been transmitted.

This commit is contained in:
adamdunkels 2010-10-24 21:08:19 +00:00
parent 8fa7bf6c31
commit 77ecfb0366

View file

@ -33,7 +33,7 @@
*
* This file is part of the Contiki operating system.
*
* $Id: collect.c,v 1.62 2010/10/19 07:34:29 adamdunkels Exp $
* $Id: collect.c,v 1.63 2010/10/24 21:08:19 adamdunkels Exp $
*/
/**
@ -125,11 +125,11 @@ struct ack_msg {
specifies the maximum length of the output queue. If the queue is
full, incoming packets are dropped instead of being forwarded. */
#define MAX_MAC_REXMITS 2
#define MAX_ACK_MAC_REXMITS 3
#define REXMIT_TIME CLOCK_SECOND * 1
#define MAX_REXMIT_TIME_SCALING 2
#define FORWARD_PACKET_LIFETIME_BASE (4 * (REXMIT_TIME))
#define MAX_SENDING_QUEUE QUEUEBUF_NUM / 2
#define MAX_ACK_MAC_REXMITS 7
#define REXMIT_TIME CLOCK_SECOND * 6
#define MAX_REXMIT_TIME_SCALING 0
#define FORWARD_PACKET_LIFETIME_BASE REXMIT_TIME
#define MAX_SENDING_QUEUE 3 * QUEUEBUF_NUM / 4
#define KEEPALIVE_REXMITS 8
#define MAX_REXMITS 31
@ -158,8 +158,8 @@ MEMB(send_queue_memb, struct packetqueue_item, MAX_SENDING_QUEUE);
queue, the system periodically sends a dummy packet to potential
parents, i.e., neighbors with a lower rtmetric than we have but for
which we do not yet have a link quality estimate. */
#define PROACTIVE_MAINTENANCE_INTERVAL CLOCK_SECOND * 60
#define PROACTIVE_MAINTENANCE_REXMITS 8
#define PROACTIVE_MAINTENANCE_INTERVAL CLOCK_SECOND * 30
#define PROACTIVE_MAINTENANCE_REXMITS 15
/* COLLECT_CONF_ANNOUNCEMENTS defines if the Collect implementation
should use Contiki's announcement primitive to announce its routes
@ -203,7 +203,6 @@ struct {
/* Debug definition: draw routing tree in Cooja. */
#define DRAW_TREE 0
#define DEBUG 0
#if DEBUG
#include <stdio.h>
@ -215,6 +214,7 @@ struct {
/* Forward declarations. */
static void send_queued_packet(struct collect_conn *c);
static void retransmit_callback(void *ptr);
static void retransmit_not_sent_callback(void *ptr);
static void set_keepalive_timer(struct collect_conn *c);
/*---------------------------------------------------------------------------*/
@ -319,9 +319,11 @@ update_parent(struct collect_conn *tc)
stats.foundroute++;
bump_advertisement(tc);
} else {
// printf("#A e=%d\n", collect_neighbor_link_estimate(best));
if(collect_neighbor_rtmetric_link_estimate(best) +
SIGNIFICANT_RTMETRIC_PARENT_CHANGE <
collect_neighbor_rtmetric_link_estimate(current)) {
/* We switch parent. */
PRINTF("update_parent: new parent %d.%d (%d) old parent %d.%d (%d)\n",
best->addr.u8[0], best->addr.u8[1],
@ -332,8 +334,6 @@ update_parent(struct collect_conn *tc)
stats.newparent++;
/* Since we now have a significantly better or worse rtmetric than
we had before, we let our neighbors know this quickly. */
PRINTF("update_rtmetric: new_rtmetric %d + %d < old_rtmetric %d\n",
new_rtmetric, SIGNIFICANT_RTMETRIC_PARENT_CHANGE, old_rtmetric);
bump_advertisement(tc);
if(DRAW_TREE) {
@ -481,6 +481,27 @@ enqueue_dummy_packet(struct collect_conn *c, int rexmits)
return 0;
}
/*---------------------------------------------------------------------------*/
static void
send_packet(struct collect_conn *c, struct collect_neighbor *n)
{
clock_time_t time;
uint8_t rexmit_time_scaling;
unicast_send(&c->unicast_conn, &n->addr);
/* Compute the retransmission timeout and set up the
retransmission timer. */
rexmit_time_scaling = c->transmissions / (MAX_MAC_REXMITS + 1);
/* if(rexmit_time_scaling > MAX_REXMIT_TIME_SCALING) {
rexmit_time_scaling = MAX_REXMIT_TIME_SCALING;
}
time = REXMIT_TIME << rexmit_time_scaling;
time = 3 * time / 2 + (random_rand() % (time / 4));*/
time = 3 * REXMIT_TIME / 4 + (random_rand() % (REXMIT_TIME / 4));
// printf("retransmission time %lu scaling %d\n", time, rexmit_time_scaling);
ctimer_set(&c->retransmission_timer, time,
retransmit_not_sent_callback, c);
}
/*---------------------------------------------------------------------------*/
/**
* This function is called when a queued packet should be sent
* out. The function takes the first packet on the output queue, adds
@ -517,7 +538,8 @@ send_queued_packet(struct collect_conn *c)
link estimate and send a dummy packet to it. This allows us to
quickly gauge the link quality of neighbors that we do not
currently use as parents. */
if(timer_expired(&c->proactive_maintenence_timer)) {
if(c->rtmetric != RTMETRIC_SINK &&
timer_expired(&c->proactive_maintenence_timer)) {
struct collect_neighbor *n;
timer_set(&c->proactive_maintenence_timer,
@ -602,7 +624,7 @@ send_queued_packet(struct collect_conn *c)
memcpy(packetbuf_dataptr(), &hdr, sizeof(struct data_msg_hdr));
/* Send the packet. */
unicast_send(&c->unicast_conn, &n->addr);
send_packet(c, n);
} else {
#if COLLECT_ANNOUNCEMENTS
@ -701,8 +723,7 @@ retransmit_current_packet(struct collect_conn *c)
memcpy(packetbuf_dataptr(), &hdr, sizeof(struct data_msg_hdr));
/* Send the packet. */
unicast_send(&c->unicast_conn, &n->addr);
send_packet(c, n);
}
}
@ -974,6 +995,7 @@ node_packet_received(struct unicast_conn *c, const rimeaddr_t *from)
ackflags |= ACK_FLAGS_RTMETRIC_NEEDS_UPDATE;
}
printf("potential loop detected\n");
packetbuf_set_attr(PACKETBUF_ATTR_HOPS,
packetbuf_attr(PACKETBUF_ATTR_HOPS) + 1);
packetbuf_set_attr(PACKETBUF_ATTR_TTL,
@ -1032,40 +1054,6 @@ node_packet_received(struct unicast_conn *c, const rimeaddr_t *from)
}
/*---------------------------------------------------------------------------*/
static void
node_packet_sent(struct unicast_conn *c, int status, int transmissions)
{
struct collect_conn *tc = (struct collect_conn *)
((char *)c - offsetof(struct collect_conn, unicast_conn));
clock_time_t time;
uint8_t rexmit_time_scaling;
/* For data packets, we record the number of transmissions */
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_DATA) {
tc->transmissions += transmissions;
PRINTF("%d.%d: MAC sent %d transmissions to %d.%d, status %d, total transmissions %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
transmissions,
tc->current_parent.u8[0], tc->current_parent.u8[1],
status, tc->transmissions);
/* Compute the retransmission timeout and set up the
retransmission timer. */
rexmit_time_scaling = tc->transmissions / (MAX_MAC_REXMITS + 1);
if(rexmit_time_scaling > MAX_REXMIT_TIME_SCALING) {
rexmit_time_scaling = MAX_REXMIT_TIME_SCALING;
}
time = REXMIT_TIME << rexmit_time_scaling;
time = time / 2 + (random_rand() % (time / 2));
PRINTF("retransmission time %lu scaling %d\n", time, rexmit_time_scaling);
ctimer_set(&tc->retransmission_timer, time,
retransmit_callback, tc);
}
}
/*---------------------------------------------------------------------------*/
static void
timedout(struct collect_conn *tc)
{
struct collect_neighbor *n;
@ -1085,6 +1073,53 @@ timedout(struct collect_conn *tc)
set_keepalive_timer(tc);
}
/*---------------------------------------------------------------------------*/
static void
node_packet_sent(struct unicast_conn *c, int status, int transmissions)
{
struct collect_conn *tc = (struct collect_conn *)
((char *)c - offsetof(struct collect_conn, unicast_conn));
/* For data packets, we record the number of transmissions */
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_DATA) {
tc->transmissions += transmissions;
// printf("tx %d\n", tc->transmissions);
PRINTF("%d.%d: MAC sent %d transmissions to %d.%d, status %d, total transmissions %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
transmissions,
tc->current_parent.u8[0], tc->current_parent.u8[1],
status, tc->transmissions);
if(tc->transmissions >= tc->max_rexmits) {
timedout(tc);
stats.timedout++;
} else {
clock_time_t time = (random_rand() % (REXMIT_TIME / 4));
// printf("retransmission time %lu scaling %d\n", time, rexmit_time_scaling);
ctimer_set(&tc->retransmission_timer, time,
retransmit_callback, tc);
}
}
}
/*---------------------------------------------------------------------------*/
/**
* This function is called from a ctimer that is setup when a packet
* is first transmitted. If the MAC layer signals that the packet is
* sent, the ctimer will be stopped before this function is called. If
* this function ends up being called, we add the maximum number of
* MAC layer transmissions to the transmission count, and call the
* retransmit function.
*/
static void
retransmit_not_sent_callback(void *ptr)
{
struct collect_conn *c = ptr;
PRINTF("retransmit not sent, %d transmissions\n", c->transmissions);
c->transmissions += MAX_MAC_REXMITS + 1;
retransmit_callback(c);
}
/*---------------------------------------------------------------------------*/
/**
* This function is called from a ctimer that is setup when a packet
* is sent. The purpose of this function is to either retransmit the
@ -1296,6 +1331,14 @@ collect_set_sink(struct collect_conn *tc, int should_be_sink)
tc->rtmetric = RTMETRIC_SINK;
PRINTF("collect_set_sink: tc->rtmetric %d\n", tc->rtmetric);
bump_advertisement(tc);
/* Purge the outgoing packet queue. */
while(packetqueue_len(&tc->send_queue) > 0) {
packetqueue_dequeue(&tc->send_queue);
}
/* Stop the retransmission timer. */
ctimer_stop(&tc->retransmission_timer);
} else {
tc->rtmetric = RTMETRIC_MAX;
}