From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH] tcp: fixing TLP's FIN recovery Date: Sat, 07 Jun 2014 17:56:06 +0400 Message-ID: <539319F6.2090907@cogentembedded.com> References: <1402081628.3645.315.camel@edumazet-glaptop2.roam.corp.google.com> <1402139419-9118-1-git-send-email-per.hurtig@kau.se> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: eric.dumazet@gmail.com, anna.brunstrom@kau.se, mohammad.rajiullah@kau.se, ncardwell@google.com, nanditad@google.com To: Per Hurtig , netdev@vger.kernel.org Return-path: Received: from mail-lb0-f178.google.com ([209.85.217.178]:42247 "EHLO mail-lb0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752650AbaFGN4F (ORCPT ); Sat, 7 Jun 2014 09:56:05 -0400 Received: by mail-lb0-f178.google.com with SMTP id w7so2155494lbi.9 for ; Sat, 07 Jun 2014 06:56:03 -0700 (PDT) In-Reply-To: <1402139419-9118-1-git-send-email-per.hurtig@kau.se> Sender: netdev-owner@vger.kernel.org List-ID: Hello. On 07-06-2014 15:10, Per Hurtig wrote: > 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. You should provide your signoff. [...] > diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c > index d463c35..6573765 100644 > --- a/net/ipv4/tcp_output.c > +++ b/net/ipv4/tcp_output.c > @@ -2130,8 +2130,10 @@ 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, if not s/not/no/? Or rather "if FIN flag is not set"? > + * FIN flag is set. > + */ > + if ((skb->len > 0) || (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) > err = __tcp_retransmit_skb(sk, skb); WBR, Sergei