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Rework of the new CSMA in-order code that fixes a number of smalllish bugs in the in-order code.

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This commit is contained in:
adamdunkels 2010-12-16 22:44:02 +00:00
parent 79f2c25dae
commit 4a89cc9db3
1 changed files with 47 additions and 16 deletions
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63
core/net/mac/csma.c
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@ -28,7 +28,7 @@
*
* This file is part of the Contiki operating system.
*
* $Id: csma.c,v 1.23 2010/12/14 07:57:14 adamdunkels Exp $
* $Id: csma.c,v 1.24 2010/12/16 22:44:02 adamdunkels Exp $
*/
/**
@ -86,7 +86,7 @@ struct queued_packet {
uint8_t collisions, deferrals;
};
#define MAX_QUEUED_PACKETS 4
#define MAX_QUEUED_PACKETS 6
MEMB(packet_memb, struct queued_packet, MAX_QUEUED_PACKETS);
LIST(queued_packet_list);
@ -94,6 +94,23 @@ static struct ctimer transmit_timer;
static void packet_sent(void *ptr, int status, int num_transmissions);
/*---------------------------------------------------------------------------*/
static clock_time_t
default_timebase(void)
{
clock_time_t time;
/* The retransmission time must be proportional to the channel
check interval of the underlying radio duty cycling layer. */
time = NETSTACK_RDC.channel_check_interval();
/* If the radio duty cycle has no channel check interval (i.e., it
does not turn the radio off), we make the retransmission time
proportional to the configured MAC channel check rate. */
if(time == 0) {
time = CLOCK_SECOND / NETSTACK_RDC_CHANNEL_CHECK_RATE;
}
return time;
}
/*---------------------------------------------------------------------------*/
static void
transmit_queued_packet(void *ptr)
@ -101,11 +118,15 @@ transmit_queued_packet(void *ptr)
/* struct queued_packet *q = ptr;*/
struct queued_packet *q;
// printf("q %d\n", list_length(queued_packet_list));
q = list_head(queued_packet_list);
if(q != NULL) {
queuebuf_to_packetbuf(q->buf);
PRINTF("csma: resending number %d %p\n", q->transmissions, q);
PRINTF("csma: sending number %d %p, queue len %d\n", q->transmissions, q,
list_length(queued_packet_list));
// printf("s %d\n", packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0]);
NETSTACK_RDC.send(packet_sent, q);
}
}
@ -113,9 +134,12 @@ transmit_queued_packet(void *ptr)
static void
start_transmission_timer(void)
{
PRINTF("csma: start_transmission_timer, queue len %d\n",
list_length(queued_packet_list));
if(list_length(queued_packet_list) > 0) {
if(ctimer_expired(&transmit_timer)) {
ctimer_set(&transmit_timer, 0, transmit_queued_packet, NULL);
ctimer_set(&transmit_timer, 0,
transmit_queued_packet, NULL);
}
}
}
@ -125,14 +149,18 @@ free_queued_packet(void)
{
struct queued_packet *q;
// printf("q %d\n", list_length(queued_packet_list));
q = list_head(queued_packet_list);
if(q != NULL) {
queuebuf_free(q->buf);
list_remove(queued_packet_list, q);
memb_free(&packet_memb, q);
PRINTF("csma: free_queued_packet, queue length %d\n",
list_length(queued_packet_list));
if(list_length(queued_packet_list) > 0) {
ctimer_set(&transmit_timer, 0, transmit_queued_packet, NULL);
ctimer_set(&transmit_timer, default_timebase(), transmit_queued_packet, NULL);
}
}
}
@ -183,14 +211,7 @@ packet_sent(void *ptr, int status, int num_transmissions)
/* The retransmission time must be proportional to the channel
check interval of the underlying radio duty cycling layer. */
time = NETSTACK_RDC.channel_check_interval();
/* If the radio duty cycle has no channel check interval (i.e., it
does not turn the radio off), we make the retransmission time
proportional to the configured MAC channel check rate. */
if(time == 0) {
time = CLOCK_SECOND / NETSTACK_RDC_CHANNEL_CHECK_RATE;
}
time = default_timebase();
/* The retransmission time uses a linear backoff so that the
interval between the transmissions increase with each
@ -203,7 +224,7 @@ packet_sent(void *ptr, int status, int num_transmissions)
if(backoff_transmissions > 3) {
backoff_transmissions = 3;
}
time = time + (random_rand() % ((backoff_transmissions) * time));
time = time + (random_rand() % (backoff_transmissions * time));
if(q->transmissions < q->max_transmissions) {
PRINTF("csma: retransmitting with time %lu %p\n", time, q);
@ -240,7 +261,7 @@ send_packet(mac_callback_t sent, void *ptr)
entry. Instead, just send it out. */
if(!rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
&rimeaddr_null) &&
packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS > 0)) {
packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS) > 0) {
/* Remember packet for later. */
q = memb_alloc(&packet_memb);
@ -259,7 +280,12 @@ send_packet(mac_callback_t sent, void *ptr)
q->deferrals = 0;
q->sent = sent;
q->cptr = ptr;
list_add(queued_packet_list, q);
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_ACK) {
list_push(queued_packet_list, q);
} else {
list_add(queued_packet_list, q);
}
start_transmission_timer();
return;
}
@ -267,6 +293,11 @@ send_packet(mac_callback_t sent, void *ptr)
PRINTF("csma: could not allocate queuebuf, will drop if collision or noack\n");
}
PRINTF("csma: could not allocate memb, will drop if collision or noack\n");
} else {
PRINTF("csma: send broadcast (%d) or without retransmissions (%d)\n",
!rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
&rimeaddr_null),
packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS));
}
NETSTACK_RDC.send(sent, ptr);
}