From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] tcp: add one more quick ack after after ECN events
Date: Thu, 28 Jun 2018 22:02:39 +0900 (KST)
Message-ID: <20180628.220239.1737584211096150988.davem@davemloft.net>
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From: Eric Dumazet <edumazet@google.com>
Date: Wed, 27 Jun 2018 08:47:21 -0700

> Larry Brakmo proposal ( https://patchwork.ozlabs.org/patch/935233/
> tcp: force cwnd at least 2 in tcp_cwnd_reduction) made us rethink
> about our recent patch removing ~16 quick acks after ECN events.
> 
> tcp_enter_quickack_mode(sk, 1) makes sure one immediate ack is sent,
> but in the case the sender cwnd was lowered to 1, we do not want
> to have a delayed ack for the next packet we will receive.
> 
> Fixes: 522040ea5fdd ("tcp: do not aggressively quick ack after ECN events")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: Neal Cardwell <ncardwell@google.com>
> Cc: Lawrence Brakmo <brakmo@fb.com>

Applied.