From 5628adf1a0ff39b9e76e1a8e1c94dadabfd46914 Mon Sep 17 00:00:00 2001
From: Neal Cardwell <ncardwell@google.com>
Date: Wed, 16 Nov 2011 08:58:02 +0000
Subject: [PATCH] tcp: use DSACKs that arrive when packets_out is 0
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

The bug: Senders ignored DSACKs after recovery when there were no
outstanding packets (a common scenario for HTTP servers).

The change: when there are no outstanding packets (the "no_queue" goto
label), call tcp_fastretrans_alert() in order to use DSACKs to undo
congestion window reductions.

Other patches in this series will provide other changes that are
necessary to fully fix this problem.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
Reading git-format-patch failed