From: Linus Lüssing linus.luessing@web.de
This decreases the size of find_router() by outsourcing the router search for the bonding and interface alternating modes to their own sub functions. This shall make it easier to keep track of the correct refcounting later.
Signed-off-by: Linus Lüssing linus.luessing@web.de Signed-off-by: Marek Lindner lindner_marek@yahoo.de Signed-off-by: Sven Eckelmann sven@narfation.org --- net/batman-adv/routing.c | 180 +++++++++++++++++++++++++++------------------- 1 files changed, 105 insertions(+), 75 deletions(-)
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index c172f5d..f212abe 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -1092,6 +1092,106 @@ out: return ret; }
+/* In the bonding case, send the packets in a round + * robin fashion over the remaining interfaces. + * + * This method rotates the bonding list and increases the + * returned router's refcount. */ +static struct neigh_node *find_bond_router(struct orig_node *primary_orig, + struct hard_iface *recv_if) +{ + struct neigh_node *tmp_neigh_node; + struct neigh_node *router = NULL, *first_candidate = NULL; + + rcu_read_lock(); + list_for_each_entry_rcu(tmp_neigh_node, &primary_orig->bond_list, + bonding_list) { + if (!first_candidate) + first_candidate = tmp_neigh_node; + + /* recv_if == NULL on the first node. */ + if (tmp_neigh_node->if_incoming == recv_if) + continue; + + if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) + continue; + + router = tmp_neigh_node; + break; + } + + /* use the first candidate if nothing was found. */ + if (!router && first_candidate && + atomic_inc_not_zero(&first_candidate->refcount)) + router = first_candidate; + + if (!router) + goto out; + + /* selected should point to the next element + * after the current router */ + spin_lock_bh(&primary_orig->neigh_list_lock); + /* this is a list_move(), which unfortunately + * does not exist as rcu version */ + list_del_rcu(&primary_orig->bond_list); + list_add_rcu(&primary_orig->bond_list, + &router->bonding_list); + spin_unlock_bh(&primary_orig->neigh_list_lock); + +out: + rcu_read_unlock(); + return router; +} + +/* Interface Alternating: Use the best of the + * remaining candidates which are not using + * this interface. + * + * Increases the returned router's refcount */ +static struct neigh_node *find_ifalter_router(struct orig_node *primary_orig, + struct hard_iface *recv_if) +{ + struct neigh_node *tmp_neigh_node; + struct neigh_node *router = NULL, *first_candidate = NULL; + + rcu_read_lock(); + list_for_each_entry_rcu(tmp_neigh_node, &primary_orig->bond_list, + bonding_list) { + if (!first_candidate) + first_candidate = tmp_neigh_node; + + /* recv_if == NULL on the first node. */ + if (tmp_neigh_node->if_incoming == recv_if) + continue; + + if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) + continue; + + /* if we don't have a router yet + * or this one is better, choose it. */ + if ((!router) || + (tmp_neigh_node->tq_avg > router->tq_avg)) { + /* decrement refcount of + * previously selected router */ + if (router) + neigh_node_free_ref(router); + + router = tmp_neigh_node; + atomic_inc_not_zero(&router->refcount); + } + + neigh_node_free_ref(tmp_neigh_node); + } + + /* use the first candidate if nothing was found. */ + if (!router && first_candidate && + atomic_inc_not_zero(&first_candidate->refcount)) + router = first_candidate; + + rcu_read_unlock(); + return router; +} + /* find a suitable router for this originator, and use * bonding if possible. increases the found neighbors * refcount.*/ @@ -1101,7 +1201,7 @@ struct neigh_node *find_router(struct bat_priv *bat_priv, { struct orig_node *primary_orig_node; struct orig_node *router_orig; - struct neigh_node *router, *first_candidate, *tmp_neigh_node; + struct neigh_node *router; static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0}; int bonding_enabled;
@@ -1157,82 +1257,12 @@ struct neigh_node *find_router(struct bat_priv *bat_priv, * in. */
neigh_node_free_ref(router); - first_candidate = NULL; - router = NULL;
- if (bonding_enabled) { - /* in the bonding case, send the packets in a round - * robin fashion over the remaining interfaces. */ + if (bonding_enabled) + router = find_bond_router(primary_orig_node, recv_if); + else + router = find_ifalter_router(primary_orig_node, recv_if);
- list_for_each_entry_rcu(tmp_neigh_node, - &primary_orig_node->bond_list, bonding_list) { - if (!first_candidate) - first_candidate = tmp_neigh_node; - /* recv_if == NULL on the first node. */ - if (tmp_neigh_node->if_incoming != recv_if && - atomic_inc_not_zero(&tmp_neigh_node->refcount)) { - router = tmp_neigh_node; - break; - } - } - - /* use the first candidate if nothing was found. */ - if (!router && first_candidate && - atomic_inc_not_zero(&first_candidate->refcount)) - router = first_candidate; - - if (!router) { - rcu_read_unlock(); - return NULL; - } - - /* selected should point to the next element - * after the current router */ - spin_lock_bh(&primary_orig_node->neigh_list_lock); - /* this is a list_move(), which unfortunately - * does not exist as rcu version */ - list_del_rcu(&primary_orig_node->bond_list); - list_add_rcu(&primary_orig_node->bond_list, - &router->bonding_list); - spin_unlock_bh(&primary_orig_node->neigh_list_lock); - - } else { - /* if bonding is disabled, use the best of the - * remaining candidates which are not using - * this interface. */ - list_for_each_entry_rcu(tmp_neigh_node, - &primary_orig_node->bond_list, bonding_list) { - if (!first_candidate) - first_candidate = tmp_neigh_node; - - /* recv_if == NULL on the first node. */ - if (tmp_neigh_node->if_incoming == recv_if) - continue; - - if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) - continue; - - /* if we don't have a router yet - * or this one is better, choose it. */ - if ((!router) || - (tmp_neigh_node->tq_avg > router->tq_avg)) { - /* decrement refcount of - * previously selected router */ - if (router) - neigh_node_free_ref(router); - - router = tmp_neigh_node; - atomic_inc_not_zero(&router->refcount); - } - - neigh_node_free_ref(tmp_neigh_node); - } - - /* use the first candidate if nothing was found. */ - if (!router && first_candidate && - atomic_inc_not_zero(&first_candidate->refcount)) - router = first_candidate; - } return_router: rcu_read_unlock(); return router;