Commit 6ef9dcb7 authored Jul 21, 2020 by Tung Nguyen Committed by David S. Miller Jul 20, 2020

tipc: allow to build NACK message in link timeout function



Commit 02288248 ("tipc: eliminate gap indicator from ACK messages")
eliminated sending of the 'gap' indicator in regular ACK messages and
only allowed to build NACK message with enabled probe/probe_reply.
However, necessary correction for building NACK message was missed
in tipc_link_timeout() function. This leads to significant delay and
link reset (due to retransmission failure) in lossy environment.

This commit fixes it by setting the 'probe' flag to 'true' when
the receive deferred queue is not empty. As a result, NACK message
will be built to send back to another peer.

Fixes: 02288248 ("tipc: eliminate gap indicator from ACK messages")
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent db44c60c

net/tipc/link.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -827,11 +827,11 @@ int tipc_link_timeout(struct tipc_link l, struct sk_buff_head xmitq)
		state \|= l->bc_rcvlink->rcv_unacked;
		state \|= l->rcv_unacked;
		state \|= !skb_queue_empty(&l->transmq);
		state \|= !skb_queue_empty(&l->deferdq);
		probe = mstate->probing;
		probe \|= l->silent_intv_cnt;
		if (probe \|\| mstate->monitoring)
		l->silent_intv_cnt++;
		probe \|= !skb_queue_empty(&l->deferdq);
		if (l->snd_nxt == l->checkpoint) {
		tipc_link_update_cwin(l, 0, 0);
		probe = true;

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