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CSMA: adopt default values from IEEE for CSMA_MIN_BE and CSMA_MAX_BE

This commit is contained in:
Simon Duquennoy 2018-02-24 15:32:36 -08:00
parent fa92115099
commit 61880704b1
1 changed files with 6 additions and 6 deletions
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12
os/net/mac/csma/csma-output.c
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@ -66,14 +66,14 @@
#ifdef CSMA_CONF_MIN_BE #ifdef CSMA_CONF_MIN_BE
#define CSMA_MIN_BE CSMA_CONF_MIN_BE #define CSMA_MIN_BE CSMA_CONF_MIN_BE
#else #else
#define CSMA_MIN_BE 0 #define CSMA_MIN_BE 3
#endif #endif
/* macMaxBE: Maximum backoff exponent. Range 3--8 */ /* macMaxBE: Maximum backoff exponent. Range 3--8 */
#ifdef CSMA_CONF_MAX_BE #ifdef CSMA_CONF_MAX_BE
#define CSMA_MAX_BE CSMA_CONF_MAX_BE #define CSMA_MAX_BE CSMA_CONF_MAX_BE
#else #else
#define CSMA_MAX_BE 4 #define CSMA_MAX_BE 5
#endif #endif
/* macMaxCSMABackoffs: Maximum number of backoffs in case of channel busy/collision. Range 0--5 */ /* macMaxCSMABackoffs: Maximum number of backoffs in case of channel busy/collision. Range 0--5 */
@ -281,7 +281,7 @@ schedule_transmission(struct neighbor_queue *n)
clock_time_t delay; clock_time_t delay;
int backoff_exponent; /* BE in IEEE 802.15.4 */ int backoff_exponent; /* BE in IEEE 802.15.4 */
backoff_exponent = MIN(n->collisions, CSMA_MAX_BE); backoff_exponent = MIN(n->collisions + CSMA_MIN_BE, CSMA_MAX_BE);
/* Compute max delay as per IEEE 802.15.4: 2^BE-1 backoff periods */ /* Compute max delay as per IEEE 802.15.4: 2^BE-1 backoff periods */
delay = ((1 << backoff_exponent) - 1) * backoff_period(); delay = ((1 << backoff_exponent) - 1) * backoff_period();
@ -310,7 +310,7 @@ free_packet(struct neighbor_queue *n, struct packet_queue *p, int status)
if(list_head(n->packet_queue) != NULL) { if(list_head(n->packet_queue) != NULL) {
/* There is a next packet. We reset current tx information */ /* There is a next packet. We reset current tx information */
n->transmissions = 0; n->transmissions = 0;
n->collisions = CSMA_MIN_BE; n->collisions = 0;
/* Schedule next transmissions */ /* Schedule next transmissions */
schedule_transmission(n); schedule_transmission(n);
} else { } else {
@ -365,7 +365,7 @@ collision(struct packet_queue *q, struct neighbor_queue *n,
n->collisions += num_transmissions; n->collisions += num_transmissions;
if(n->collisions > CSMA_MAX_BACKOFF) { if(n->collisions > CSMA_MAX_BACKOFF) {
n->collisions = CSMA_MIN_BE; n->collisions = 0;
/* Increment to indicate a next retry */ /* Increment to indicate a next retry */
n->transmissions++; n->transmissions++;
} }
@ -384,7 +384,7 @@ noack(struct packet_queue *q, struct neighbor_queue *n, int num_transmissions)
metadata = (struct qbuf_metadata *)q->ptr; metadata = (struct qbuf_metadata *)q->ptr;
n->collisions = CSMA_MIN_BE; n->collisions = 0;
n->transmissions += num_transmissions; n->transmissions += num_transmissions;
if(n->transmissions >= metadata->max_transmissions) { if(n->transmissions >= metadata->max_transmissions) {