Patch "tcp: cwnd does not increase in TCP YeAH" has been added to the 4.7-stable tree

Patch "tcp: cwnd does not increase in TCP YeAH" has been added to the 4.7-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    tcp: cwnd does not increase in TCP YeAH

to the 4.7-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     tcp-cwnd-does-not-increase-in-tcp-yeah.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Wed Sep 21 10:05:18 CEST 2016
From: Artem Germanov <agermanov@anchorfree.com>
Date: Wed, 7 Sep 2016 10:49:36 -0700
Subject: tcp: cwnd does not increase in TCP YeAH

From: Artem Germanov <agermanov@anchorfree.com>


[ Upstream commit db7196a0d0984b933ccf2cd6a60e26abf466e8a3 ]

Commit 76174004a0f19785a328f40388e87e982bbf69b9
(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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/tcp_yeah.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/ipv4/tcp_yeah.c
+++ b/net/ipv4/tcp_yeah.c
@@ -76,7 +76,7 @@ static void tcp_yeah_cong_avoid(struct s
 	if (!tcp_is_cwnd_limited(sk))
 		return;
 
-	if (tp->snd_cwnd <= tp->snd_ssthresh)
+	if (tcp_in_slow_start(tp))
 		tcp_slow_start(tp, acked);
 
 	else if (!yeah->doing_reno_now) {


Patches currently in stable-queue which might be from agermanov@anchorfree.com are

queue-4.7/tcp-cwnd-does-not-increase-in-tcp-yeah.patch