Received: by 2002:a05:6a10:9848:0:0:0:0 with SMTP id x8csp3496683pxf; Mon, 15 Mar 2021 10:49:45 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzWUVDtcYIpW1i+Po6fC16vvNzApteA0ruEaWOorMq8HHwhazAd1pwysfAsDnX8OOmU7Ljx X-Received: by 2002:a17:906:f12:: with SMTP id z18mr25167394eji.132.1615830585708; Mon, 15 Mar 2021 10:49:45 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1615830585; cv=none; d=google.com; s=arc-20160816; b=yiIkxD/ld6yWTQxfo0W8bKeT3jU56TVKGvx36K8xDRk5SKI2SA4iVFtwM+GzIsz6+O /9YsYtS6XYACYNlZoqpveVH8MOW++Xpi5iOJvI6a+o15GmqlW5XUXCG+DI8hvLcytrok LhkpTzQfhjtoEj0xDEpErX/eLfws1/u0FLtQFbtNcxxPpzerTwKCH5mPdlk+2vNlg8/T FiDWUL59JY+IuB+5Pbb07qhSxMKWyqHWXLWZh6Ubbd0r8kjcXZj6cksaWdowgZTv/3oH Kl0u1TPIYxT7aI/enUTUdMfBjQQvy4FNjCbDvds+9MCYgc7zUK1eiJCQWZ+c2t2CAlA4 UD2w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:user-agent:in-reply-to:content-disposition :mime-version:references:message-id:subject:cc:to:from:date; bh=IBYwTdvxwX7U4njHIMTI4tx5VyiVRq24/XRVk4vjQXw=; b=hZuKcXiewmjtY8jUUrpYxZ5DdVYRwiq8umhPrRPyXELdhd6WvmeLlMJqmWwjopU7xU p/EBSG7Rauy1Xsig7ih0ahpgBT19znd9s5jYwpxvbkIftB4r0L0QkqJ0ISsLjCBnk6wb QUbpYT8tFZ8pzn1+Eg0cklNtJ4iUYP6N5hNc3CpQ6L9v3qoj7SiVAWx0ZST2wG/kd2lS uR1e+i6E1uaQ5stylDqOyko8GslQAybKLP9SSemsnjwIrG/OEu0dnpF//hjz31BeNLdU 3UwRKMY7ecOO66bxFPXXEXKG1XsRL+lUEU7UxOcA1Okvnz3rwy1iqZckHoLIvFCJa5it O4oA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id e21si10947134edr.370.2021.03.15.10.49.21; Mon, 15 Mar 2021 10:49:45 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229505AbhCORmb (ORCPT + 99 others); Mon, 15 Mar 2021 13:42:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232196AbhCORmW (ORCPT ); Mon, 15 Mar 2021 13:42:22 -0400 X-Greylist: delayed 110955 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Mon, 15 Mar 2021 10:42:21 PDT Received: from mail.netfilter.org (mail.netfilter.org [IPv6:2001:4b98:dc0:41:216:3eff:fe8c:2bda]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C5FFBC06174A; Mon, 15 Mar 2021 10:42:21 -0700 (PDT) Received: from us.es (unknown [90.77.255.23]) by mail.netfilter.org (Postfix) with ESMTPSA id C272D63535; Mon, 15 Mar 2021 18:42:18 +0100 (CET) Date: Mon, 15 Mar 2021 18:42:17 +0100 From: Pablo Neira Ayuso To: Mark Tomlinson Cc: kadlec@netfilter.org, fw@strlen.de, subashab@codeaurora.org, netfilter-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 0/3] Don't use RCU for x_tables synchronization Message-ID: <20210315174217.GA25425@salvia> References: <20210308012413.14383-1-mark.tomlinson@alliedtelesis.co.nz> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210308012413.14383-1-mark.tomlinson@alliedtelesis.co.nz> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 08, 2021 at 02:24:10PM +1300, Mark Tomlinson wrote: > The patches to change to using RCU synchronization in x_tables cause > updating tables to be slowed down by an order of magnitude. This has > been tried before, see https://lore.kernel.org/patchwork/patch/151796/ > and ultimately was rejected. As mentioned in the patch description, a > different method can be used to ensure ordering of reads/writes. This > can simply be done by changing from smp_wmb() to smp_mb(). Applied.