batman-adv: Simple (re)broadcast avoidance

With this patch, (re)broadcasting on a specific interfaces is avoided:

* No neighbor: There is no need to broadcast on an interface if there
  is no node behind it.

* Single neighbor is source: If there is just one neighbor on an
  interface and if this neighbor is the one we actually got this
  broadcast packet from, then we do not need to echo it back.

* Single neighbor is originator: If there is just one neighbor on
  an interface and if this neighbor is the originator of this
  broadcast packet, then we do not need to echo it back.

Goodies for BATMAN V:

("Upgrade your BATMAN IV network to V now to get these for free!")

Thanks to the split of OGMv1 into two packet types, OGMv2 and ELP
that is, we can now apply the same optimizations stated above to OGMv2
packets, too.

Furthermore, with BATMAN V, rebroadcasts can be reduced in certain
multi interface cases, too, where BATMAN IV cannot. This is thanks to
the removal of the "secondary interface originator" concept in BATMAN V.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/batman-adv/send.h b/net/batman-adv/send.h
index 999f78683d9e..86009b59201e 100644
--- a/net/batman-adv/send.h
+++ b/net/batman-adv/send.h
@@ -46,7 +46,8 @@ int batadv_send_unicast_skb(struct sk_buff *skb,
 			    struct batadv_neigh_node *neigh_node);
 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 				    const struct sk_buff *skb,
-				    unsigned long delay);
+				    unsigned long delay,
+				    bool own_packet);
 void
 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 				 const struct batadv_hard_iface *hard_iface);