tcp: cwnd does not increase in TCP YeAH

Commit 76174004a0
(tcp: do not slow start when cwnd equals ssthresh )
introduced regression in TCP YeAH. Using 100ms delay 1% loss virtual
ethernet link kernel 4.2 shows bandwidth ~500KB/s for single TCP
connection and kernel 4.3 and above (including 4.8-rc4) shows bandwidth
~100KB/s.
   That is caused by stalled cwnd when cwnd equals ssthresh. This patch
fixes it by proper increasing cwnd in this case.

Signed-off-by: Artem Germanov <agermanov@anchorfree.com>
Acked-by: Dmitry Adamushko <d.adamushko@anchorfree.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Artem Germanov 2016-09-07 10:49:36 -07:00 committed by David S. Miller
parent 81d1a366ff
commit db7196a0d0

View file

@ -76,7 +76,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked)
if (!tcp_is_cwnd_limited(sk)) if (!tcp_is_cwnd_limited(sk))
return; return;
if (tp->snd_cwnd <= tp->snd_ssthresh) if (tcp_in_slow_start(tp))
tcp_slow_start(tp, acked); tcp_slow_start(tp, acked);
else if (!yeah->doing_reno_now) { else if (!yeah->doing_reno_now) {