tipc: reset all unicast links when broadcast send link fails

In test situations with many nodes and a heavily stressed system we have
observed that the transmission broadcast link may fail due to an
excessive number of retransmissions of the same packet. In such
situations we need to reset all unicast links to all peers, in order to
reset and re-synchronize the broadcast link.

In this commit, we add a new function tipc_bearer_reset_all() to be used
in such situations. The function scans across all bearers and resets all
their pertaining links.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 4 deletions

diff --git a/net/tipc/node.c b/net/tipc/node.c
index e01e2c71b5a1..23d4761842a0 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -1297,10 +1297,6 @@ static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id
 
         rc = tipc_bcast_rcv(net, be->link, skb);
 
-        /* Broadcast link reset may happen at reassembly failure */
-        if (rc & TIPC_LINK_DOWN_EVT)
-                tipc_node_reset_links(n);
-
         /* Broadcast ACKs are sent on a unicast link */
         if (rc & TIPC_LINK_SND_BC_ACK) {
                 tipc_node_read_lock(n);
@@ -1320,6 +1316,17 @@ static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id
                 spin_unlock_bh(&be->inputq2.lock);
                 tipc_sk_mcast_rcv(net, &be->arrvq, &be->inputq2);
         }
+
+        if (rc & TIPC_LINK_DOWN_EVT) {
+                /* Reception reassembly failure => reset all links to peer */
+                if (!tipc_link_is_up(be->link))
+                        tipc_node_reset_links(n);
+
+                /* Retransmission failure => reset all links to all peers */
+                if (!tipc_link_is_up(tipc_bc_sndlink(net)))
+                        tipc_bearer_reset_all(net);
+        }
+
         tipc_node_put(n);
 }