From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next v4 0/4] ila: Optimization to preserve value of early demux Date: Mon, 14 Dec 2015 16:19:53 -0500 (EST) Message-ID: <20151214.161953.1429843640262699390.davem@davemloft.net> References: <1449793173-4086221-1-git-send-email-tom@herbertland.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, kernel-team@fb.com To: tom@herbertland.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:60638 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932194AbbLNVTz (ORCPT ); Mon, 14 Dec 2015 16:19:55 -0500 In-Reply-To: <1449793173-4086221-1-git-send-email-tom@herbertland.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Tom Herbert Date: Thu, 10 Dec 2015 16:19:29 -0800 > In the current implementation of ILA, LWT is used to perform > translation on both the input and output paths. This is functional, > however there is a big performance hit in the receive path. Early > demux occurs before the routing lookup (a hit actually obviates the > route lookup). Therefore the stack currently performs early > demux before translation so that a local connection with ILA > addresses is never matched. Note that this issue is not just > with ILA, but pretty much any translated or encapsulated packet > handled by LWT would miss the opportunity for early demux. Solving > the general problem seems non trivial since we would need to move > the route lookup before early demx thereby mitigating the value. > > This patch set addresses the issue for ILA by adding a fast locator > lookup that occurs before early demux. This done by hooking in to > NF_INET_PRE_ROUTING > > For the backend we implement an rhashtable that contains identifier > to locator to mappings. The table also allows more specific matches > that include original locator and interface. ... Please address Florian's feedback wrt. which nf hook registry interface should be used, and otherwise I think this series is ready to go.