From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 16BF0C433F5 for ; Wed, 27 Apr 2022 15:10:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239101AbiD0POI (ORCPT ); Wed, 27 Apr 2022 11:14:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239548AbiD0POH (ORCPT ); Wed, 27 Apr 2022 11:14:07 -0400 Received: from mail.netfilter.org (mail.netfilter.org [217.70.188.207]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 76A1127CE1 for ; Wed, 27 Apr 2022 08:10:55 -0700 (PDT) Date: Wed, 27 Apr 2022 17:10:50 +0200 From: Pablo Neira Ayuso To: Ritaro Takenaka Cc: netfilter-devel@vger.kernel.org Subject: Re: [PATCH] nf_flowtable: ensure dst.dev is not blackhole Message-ID: References: <20220425080835.5765-1-ritarot634@gmail.com> <04e2c223-7936-481d-0032-0a55a21dca7a@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <04e2c223-7936-481d-0032-0a55a21dca7a@gmail.com> Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org On Tue, Apr 26, 2022 at 09:28:13PM +0900, Ritaro Takenaka wrote: > Thanks for your reply. > > > In 5.4, this check is only enabled for xfrm. > Packet loss occurs with xmit (xfrm is not confirmed). > I also experienced packet loss with 5.10, which runs dst_check periodically. > Route GC and flowtable GC are not synchronized, so it is > necessary to check each packet. > > > dst_check() should deal with this. > When dst_check is used, the performance degradation is not negligible. > From 900 Mbps to 700 Mbps with QCA9563 simple firewall. You mention 5.10 above. Starting 5.12, dst_check() uses INDIRECT_CALL_INET. Is dst_check() still slow with >= 5.12? Asking this because my understanding (at this stage) is that this check for blackhole_netdev is a faster way to check for stale cached routes.