From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: tcp: fixing TLP's FIN recovery Date: Fri, 06 Jun 2014 12:07:08 -0700 Message-ID: <1402081628.3645.315.camel@edumazet-glaptop2.roam.corp.google.com> References: <20140606184626.GA13509@kau.se> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, anna.brunstrom@kau.se, mohammad.rajiullah@kau.se, Neal Cardwell , Nandita Dukkipati To: Per Hurtig Return-path: Received: from mail-pb0-f44.google.com ([209.85.160.44]:43560 "EHLO mail-pb0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752423AbaFFTHK (ORCPT ); Fri, 6 Jun 2014 15:07:10 -0400 Received: by mail-pb0-f44.google.com with SMTP id rq2so2849418pbb.3 for ; Fri, 06 Jun 2014 12:07:10 -0700 (PDT) In-Reply-To: <20140606184626.GA13509@kau.se> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, 2014-06-06 at 20:46 +0200, Per Hurtig wrote: > From ab1b16ef8aba4300b1a6e965c3ab7d0cb269bb2a Mon Sep 17 00:00:00 2001 > From: Per Hurtig > Date: Fri, 6 Jun 2014 18:36:19 +0200 > Subject: [PATCH 1/1] tcp: fixing TLP's FIN recovery > > Fix to a problem observed when losing a FIN segment that does not > contain data. In such situations, TLP is unable to recover from > *any* tail loss and instead adds at least PTO ms to the > retransmission process, i.e., RTO = RTO + PTO. > > Signed-off-by: Per Hurtig > --- > net/ipv4/tcp_output.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c > index d463c35..2c29926 100644 > --- a/net/ipv4/tcp_output.c > +++ b/net/ipv4/tcp_output.c > @@ -2130,8 +2130,9 @@ void tcp_send_loss_probe(struct sock *sk) > if (WARN_ON(!skb || !tcp_skb_pcount(skb))) > goto rearm_timer; > > - /* Probe with zero data doesn't trigger fast recovery. > */ > - if (skb->len > 0) > + /* Probe with zero data doesn't trigger fast > recovery, unless > + * FIN flag is set. */ > + if ((skb->len > 0) || > (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) > err = __tcp_retransmit_skb(sk, skb); > > /* Record snd_nxt for loss detection. */ > -- > 1.9.1 > Patch was mangled. Please fix and resend. Please CC Nandita & Neal, Thanks