Avoid hysteresis check if neither p1 nor p2 is the preferred parent.

This commit is contained in:
nvt 2011-03-04 16:40:40 +01:00
parent dd7cec737d
commit a7addf990f

View File

@ -153,13 +153,15 @@ best_parent(rpl_parent_t *p1, rpl_parent_t *p2)
p2_etx = calculate_etx(p2);
/* Maintain stability of the preferred parent in case of similar ranks. */
if(p1_etx < p2_etx + min_diff &&
p1_etx > p2_etx - min_diff) {
PRINTF("RPL: MRHOF hysteresis: %u <= %u <= %u\n",
p2_etx - min_diff,
p1_etx,
p2_etx + min_diff);
return dag->preferred_parent;
if(p1 == dag->preferred_parent || p2 == dag->preferred_parent) {
if(p1_etx < p2_etx + min_diff &&
p1_etx > p2_etx - min_diff) {
PRINTF("RPL: MRHOF hysteresis: %u <= %u <= %u\n",
p2_etx - min_diff,
p1_etx,
p2_etx + min_diff);
return dag->preferred_parent;
}
}
return p1_etx < p2_etx ? p1 : p2;