{"id":747,"url":"http://patchwork.ozlabs.org/api/1.0/patches/747/?format=json","project":{"id":7,"url":"http://patchwork.ozlabs.org/api/1.0/projects/7/?format=json","name":"Linux network development","link_name":"netdev","list_id":"netdev.vger.kernel.org","list_email":"netdev@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null},"msgid":"<1221947278-16715-16-git-send-email-ilpo.jarvinen@helsinki.fi>","date":"2008-09-20T21:47:58","name":"[PATCHv2,net-next,15/15] tcp: back retransmit_high when it over-estimated","commit_ref":null,"pull_url":null,"state":"accepted","archived":true,"hash":"4a53530360a1656978bece47e12f0e14e2418aff","submitter":{"id":255,"url":"http://patchwork.ozlabs.org/api/1.0/people/255/?format=json","name":"Ilpo Järvinen","email":"ilpo.jarvinen@helsinki.fi"},"delegate":{"id":34,"url":"http://patchwork.ozlabs.org/api/1.0/users/34/?format=json","username":"davem","first_name":"David","last_name":"Miller","email":"davem@davemloft.net"},"mbox":"http://patchwork.ozlabs.org/project/netdev/patch/1221947278-16715-16-git-send-email-ilpo.jarvinen@helsinki.fi/mbox/","series":[],"check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/747/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Received":["from vger.kernel.org (vger.kernel.org [209.132.176.167])\n\tby ozlabs.org (Postfix) with ESMTP id 2AA59DDE98\n\tfor ;\n\tSun, 21 Sep 2008 07:48:30 +1000 (EST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1752112AbYITVsY (ORCPT );\n\tSat, 20 Sep 2008 17:48:24 -0400","(majordomo@vger.kernel.org) by vger.kernel.org id S1753127AbYITVsU\n\t(ORCPT ); Sat, 20 Sep 2008 17:48:20 -0400","from courier.cs.helsinki.fi ([128.214.9.1]:45382 \"EHLO\n\tmail.cs.helsinki.fi\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1752624AbYITVsN (ORCPT\n\t); Sat, 20 Sep 2008 17:48:13 -0400","from wrl-59.cs.helsinki.fi (wrl-59.cs.helsinki.fi\n\t[128.214.166.179])\n\t(AUTH: PLAIN cs-relay, TLS: TLSv1/SSLv3,256bits,AES256-SHA)\n\tby mail.cs.helsinki.fi with esmtp; Sun, 21 Sep 2008 00:47:59 +0300\n\tid 0005BEF4.48D56F8F.000054E1","by wrl-59.cs.helsinki.fi (Postfix, from userid 50795)\n\tid 2331FA00A5; Sun, 21 Sep 2008 00:47:59 +0300 (EEST)"],"From":"\"=?ISO-8859-1?Q?Ilpo_J=E4rvinen?=\" ","To":"David Miller ","Cc":"netdev@vger.kernel.org,\n\t\"=?utf-8?q?Ilpo=20J=E4rvinen?=\" ","Subject":"[PATCHv2 net-next 15/15] tcp: back retransmit_high when it\n\tover-estimated","Date":"Sun, 21 Sep 2008 00:47:58 +0300","Message-Id":"<1221947278-16715-16-git-send-email-ilpo.jarvinen@helsinki.fi>","X-Mailer":"git-send-email 1.5.4.2.156.ge3c5","In-Reply-To":"<1221947278-16715-15-git-send-email-ilpo.jarvinen@helsinki.fi>","References":"<1221947278-16715-1-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-2-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-3-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-4-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-5-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-6-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-7-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-8-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-9-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-10-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-11-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-12-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-13-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-14-git-send-email-ilpo.jarvinen@helsinki.fi>\n\t<1221947278-16715-15-git-send-email-ilpo.jarvinen@helsinki.fi>","MIME-Version":"1.0","Content-Type":"text/plain; charset=ISO-8859-1","Content-Transfer-Encoding":"8bit","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"},"content":"If lost skb is sacked, we might have nothing to retransmit\nas high as the retransmit_high is pointing to, so place\nit lower to avoid unnecessary walking.\n\nThis is mainly for the case where high L'ed skbs gets sacked.\n\nSigned-off-by: Ilpo Järvinen \n---\n net/ipv4/tcp_output.c | 12 ++++++++++--\n 1 files changed, 10 insertions(+), 2 deletions(-)","diff":"diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c\nindex 63b9ce1..b28eeb0 100644\n--- a/net/ipv4/tcp_output.c\n+++ b/net/ipv4/tcp_output.c\n@@ -2033,16 +2033,22 @@ void tcp_xmit_retransmit_queue(struct sock *sk)\n \tstruct tcp_sock *tp = tcp_sk(sk);\n \tstruct sk_buff *skb;\n \tstruct sk_buff *hole = NULL;\n+\tu32 last_lost;\n \tint mib_idx;\n \tint fwd_rexmitting = 0;\n \n \tif (!tp->lost_out)\n \t\ttp->retransmit_high = tp->snd_una;\n \n-\tif (tp->retransmit_skb_hint)\n+\tif (tp->retransmit_skb_hint) {\n \t\tskb = tp->retransmit_skb_hint;\n-\telse\n+\t\tlast_lost = TCP_SKB_CB(skb)->end_seq;\n+\t\tif (after(last_lost, tp->retransmit_high))\n+\t\t\tlast_lost = tp->retransmit_high;\n+\t} else {\n \t\tskb = tcp_write_queue_head(sk);\n+\t\tlast_lost = tp->snd_una;\n+\t}\n \n \t/* First pass: retransmit lost packets. */\n \ttcp_for_write_queue_from(skb, sk) {\n@@ -2071,6 +2077,7 @@ begin_fwd:\n \t\t\tmib_idx = LINUX_MIB_TCPFORWARDRETRANS;\n \n \t\t} else if (!before(TCP_SKB_CB(skb)->seq, tp->retransmit_high)) {\n+\t\t\ttp->retransmit_high = last_lost;\n \t\t\tif (!tcp_can_forward_retransmit(sk))\n \t\t\t\tbreak;\n \t\t\t/* Backtrack if necessary to non-L'ed skb */\n@@ -2087,6 +2094,7 @@ begin_fwd:\n \t\t\tcontinue;\n \n \t\t} else {\n+\t\t\tlast_lost = TCP_SKB_CB(skb)->end_seq;\n \t\t\tif (icsk->icsk_ca_state != TCP_CA_Loss)\n \t\t\t\tmib_idx = LINUX_MIB_TCPFASTRETRANS;\n \t\t\telse\n","prefixes":["PATCHv2","net-next","15/15"]}