Commit 41727549 authored Dec 05, 2018 by Eric Dumazet Committed by David S. Miller Dec 05, 2018

tcp: Do not underestimate rwnd_limited



If available rwnd is too small, tcp_tso_should_defer()
can decide it is worth waiting before splitting a TSO packet.

This really means we are rwnd limited.

Fixes: 5615f886 ("tcp: instrument how long TCP is limited by receive window")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent e37d05a5

net/ipv4/tcp_output.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -2356,9 +2356,12 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
		} else {
		if (!push_one &&
		tcp_tso_should_defer(sk, skb, &is_cwnd_limited,
		max_segs))
		max_segs)) {
		if (!is_cwnd_limited)
		is_rwnd_limited = true;
		break;
		}
		}

		limit = mss_now;
		if (tso_segs > 1 && !tcp_urg_mode(tp))