tipc: let first message on link be a state message
According to the link FSM, a received traffic packet can take a link
from state ESTABLISHING to ESTABLISHED, but the link can still not be
fully set up in one atomic operation. This means that even if the the
very first packet on the link is a traffic packet with sequence number
1 (one), it has to be dropped and retransmitted.
This can be avoided if we let the mentioned packet be preceded by a
LINK_PROTOCOL/STATE message, which takes up the endpoint before the
arrival of the traffic.
We add this small feature in this commit.
This is a fully compatible change.
Acked-by: Ying Xue <[email protected]>
Signed-off-by: Jon Maloy <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
diff --git a/net/tipc/link.c b/net/tipc/link.c
index 774ad3c..2e28a7d 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1107,12 +1107,12 @@
return released;
}
-/* tipc_link_build_ack_msg: prepare link acknowledge message for transmission
+/* tipc_link_build_state_msg: prepare link state message for transmission
*
* Note that sending of broadcast ack is coordinated among nodes, to reduce
* risk of ack storms towards the sender
*/
-int tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
+int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
{
if (!l)
return 0;
@@ -1222,7 +1222,7 @@
if (!tipc_data_input(l, skb, l->inputq))
rc |= tipc_link_input(l, skb, l->inputq);
if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
- rc |= tipc_link_build_ack_msg(l, xmitq);
+ rc |= tipc_link_build_state_msg(l, xmitq);
if (unlikely(rc & ~TIPC_LINK_SND_BC_ACK))
break;
} while ((skb = __skb_dequeue(defq)));