From: Simon Wunderlich simon@open-mesh.com
With the new interface alternating, the first hop may send packets in a round robin fashion to it's neighbors because it has multiple valid routes built by the multi interface optimization. This patch enables the feature if bonding is selected. Note that unlike the bonding implemented before, this version is much simpler and may even enable multi path routing to a certain degree.
Signed-off-by: Simon Wunderlich simon@open-mesh.com --- routing.c | 104 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-- routing.h | 2 +- types.h | 2 ++ 3 files changed, 104 insertions(+), 4 deletions(-)
diff --git a/routing.c b/routing.c index c1b6d85..87591b6 100644 --- a/routing.c +++ b/routing.c @@ -403,9 +403,15 @@ static int batadv_check_unicast_packet(struct batadv_priv *bat_priv, struct batadv_neigh_node * batadv_find_router(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node, - const struct batadv_hard_iface *recv_if) + struct batadv_hard_iface *recv_if) { - struct batadv_neigh_node *router; + struct batadv_neigh_node *router, *cand_router, + *first_candidate_router = NULL, + *next_candidate_router; + struct batadv_neigh_node_ifinfo *router_ifinfo, *cand_ifinfo; + struct batadv_orig_node_ifinfo *cand, *first_candidate = NULL, + *next_candidate = NULL; + bool last_candidate_found = false;
if (!orig_node) return NULL; @@ -414,7 +420,99 @@ batadv_find_router(struct batadv_priv *bat_priv, if (!router) return NULL;
- /* TODO: fill this later with new bonding mechanism */ + /* only consider bonding for recv_if == NULL (first hop) and if + * activated. + */ + if (recv_if || !atomic_read(&bat_priv->bonding)) + return router; + + /* bonding: loop through the list of possible routers found + * for the various outgoing interfaces and find a candidate after + * the last chosen bonding candidate (next_candidate). If no such + * router is found, use the first candidate found (the last chosen + * bonding candidate might have been the last one in the list). + * If this can't be found either, return the previously choosen + * router - obviously there are no other candidates. + */ + rcu_read_lock(); + router_ifinfo = batadv_neigh_node_get_ifinfo(router, recv_if); + hlist_for_each_entry_rcu(cand, &orig_node->ifinfo_list, + list) { + cand_router = rcu_dereference(cand->router); + if (!cand_router) + continue; + + if (!atomic_inc_not_zero(&cand_router->refcount)) + continue; + + cand_ifinfo = batadv_neigh_node_get_ifinfo(cand_router, + cand->if_outgoing); + if (!cand_ifinfo) + goto next; + + /* alternative candidate should be good enough to be + * considered + */ + if (cand_ifinfo->tq_avg < + (router_ifinfo->tq_avg - BATADV_BONDING_TQ_THRESHOLD)) + goto next; + + /* don't use the same router twice */ + if (orig_node->last_bonding_candidate && + (orig_node->last_bonding_candidate->router == + cand_router)) + goto next; + + /* mark the first possible candidate */ + if (!first_candidate) { + atomic_inc(&cand_router->refcount); + first_candidate = cand; + first_candidate_router = cand_router; + } + + /* check if already passed the next candidate ... this function + * should get the next candidate AFTER the last used bonding + * candidate. + */ + if (orig_node->last_bonding_candidate) { + if (orig_node->last_bonding_candidate == cand) { + last_candidate_found = true; + goto next; + } + + if (!last_candidate_found) + goto next; + } + + next_candidate = cand; + next_candidate_router = cand_router; + break; +next: + batadv_neigh_node_free_ref(cand_router); + } + + if (next_candidate) { + /* found a possible candidate after the last chosen bonding + * candidate, return it. + */ + batadv_neigh_node_free_ref(router); + if (first_candidate) + batadv_neigh_node_free_ref(first_candidate_router); + router = next_candidate_router; + orig_node->last_bonding_candidate = next_candidate; + } else if (first_candidate) { + /* found no possible candidate after the last candidate, return + * the first candidate if available, or the already selected + * router otherwise. + */ + batadv_neigh_node_free_ref(router); + router = first_candidate_router; + orig_node->last_bonding_candidate = first_candidate; + } else { + orig_node->last_bonding_candidate = NULL; + } + + rcu_read_unlock();
return router; } diff --git a/routing.h b/routing.h index 7a7c6e9..2c80b6a 100644 --- a/routing.h +++ b/routing.h @@ -46,7 +46,7 @@ int batadv_recv_unhandled_unicast_packet(struct sk_buff *skb, struct batadv_neigh_node * batadv_find_router(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node, - const struct batadv_hard_iface *recv_if); + struct batadv_hard_iface *recv_if); int batadv_window_protected(struct batadv_priv *bat_priv, int32_t seq_num_diff, unsigned long *last_reset);
diff --git a/types.h b/types.h index 37bf7db..f043125 100644 --- a/types.h +++ b/types.h @@ -135,6 +135,7 @@ struct batadv_frag_list_entry { * @orig: originator ethernet address * @primary_addr: hosts primary interface address * @ifinfo_list: list for routers per outgoing interface + * @last_bonding_candidate: pointer to last ifinfo of last used router * @batadv_dat_addr_t: address of the orig node in the distributed hash * @bcast_own: bitfield containing the number of our OGMs this orig_node * rebroadcasted "back" to us (relative to last_real_seqno) @@ -175,6 +176,7 @@ struct batadv_orig_node { uint8_t orig[ETH_ALEN]; uint8_t primary_addr[ETH_ALEN]; struct hlist_head ifinfo_list; + struct batadv_orig_node_ifinfo *last_bonding_candidate; #ifdef CONFIG_BATMAN_ADV_DAT batadv_dat_addr_t dat_addr; #endif