Commit 860975c6 authored Nov 19, 2020 by Florian Westphal Committed by Jakub Kicinski Nov 20, 2020

mptcp: skip to next candidate if subflow has unacked data



In case a subflow path is blocked, MPTCP-level retransmit may not take
place anymore because such subflow is likely to have unacked data left
in its write queue.

Ignore subflows that have experienced loss and test next candidate.

Fixes: 3b1d6210 ("mptcp: implement and use MPTCP-level retransmission")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

parent 26aa2314

net/mptcp/protocol.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1726,8 +1726,11 @@ static struct sock mptcp_subflow_get_retrans(const struct mptcp_sock msk)
		continue;

		/* still data outstanding at TCP level? Don't retransmit. */
		if (!tcp_write_queue_empty(ssk))
		if (!tcp_write_queue_empty(ssk)) {
		if (inet_csk(ssk)->icsk_ca_state >= TCP_CA_Loss)
		continue;
		return NULL;
		}

		if (subflow->backup) {
		if (!backup)

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