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 X-Spam-Level: X-Spam-Status: No, score=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4690FC433EF for ; Thu, 16 Sep 2021 09:40:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2BCED6112E for ; Thu, 16 Sep 2021 09:40:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235966AbhIPJmD (ORCPT ); Thu, 16 Sep 2021 05:42:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229494AbhIPJmB (ORCPT ); Thu, 16 Sep 2021 05:42:01 -0400 Received: from mail-lf1-x133.google.com (mail-lf1-x133.google.com [IPv6:2a00:1450:4864:20::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D01AC061574; Thu, 16 Sep 2021 02:40:41 -0700 (PDT) Received: by mail-lf1-x133.google.com with SMTP id h16so16049160lfk.10; Thu, 16 Sep 2021 02:40:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=f4r5L82T8lVgmjDxktA/sisuupFmx7x30+6IlhMnYag=; b=jPcF0P+cHfyIuFllT9s+XQDbpTKL/DP/WZ12xBmDnC0LZJsbJeGpydQ+nj1jG3vyhQ MXkF+s9f9DZe82C3OUmuCqssXSW6Xy1D8PFT7XMOVkyU74aEXJL7HBQJL//WLAcHnHlT 6JAWY0XBjZ7XwV9xpdiHpNmVxyHHj5cWcQPRN6QHBZx1dqJ5C5ttXeA+io6IcnyWEI1q dTKH6A8fDq2gQ2GNoUTTZGZkVAhST9ZUJ+pdKy05GPpnzXG3EkGwi93ZGAuCS4fkFkql PEeqVQZUULvnCU7rK1P4+9aDwbpW2w/MkOtNecCIBYtcqqkOy4RB/4LhCrlLfobSeeON wc2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=f4r5L82T8lVgmjDxktA/sisuupFmx7x30+6IlhMnYag=; b=d04CrElN+9LPFiaWg1zURVABzwjkEb76HQgpIWxTIjVr4nosqwCnbKO1ax7BMFt4Xz VC1trQ0VRjoJiEYb4kD5JVaREOQtjVzJdyglz87/vZGbZR90Jb/zYHWXdSlZQcgjbK48 diS3URh+bIfi9ERq957JnZuox8NDamdyU5trBs9+p4ApfJz2dPxo0fNuxUb/VpBT9Bzn AhPbuyDtRyTvTx8HY4YM1C7+RMnjRlmUi6KHnxHZDOzQxoDs5I5hEO7xZutprJKJnj0F QYLM2JnUM/g4WTM/ofUJPYttHzggw9olPcW0QEHt9L1dZl8L8s7jWk2L6018V6u6OaMO NYzA== X-Gm-Message-State: AOAM5333fyZugtkXw++Qe9/ZSHnRPIuZnJhWWDKTTJ/5yGEFvM7RO7wa EJjeSxj62CZK5zr2dqWOkL2z9W9yOEa2yVL1cEg= X-Google-Smtp-Source: ABdhPJyIIyf4A7fhfDx7l6dTfpk1Ec/zzEqy4u9mdnznrZCiaqfyA9V5XQj08EEuePeq9U7P318zvMYzkOuwjxToNGM= X-Received: by 2002:a2e:1508:: with SMTP id s8mr3587923ljd.240.1631785239506; Thu, 16 Sep 2021 02:40:39 -0700 (PDT) MIME-Version: 1.0 References: <20210914151016.3174924-1-Roman_Skakun@epam.com> <7c04db79-7de1-93ff-0908-9bad60a287b9@suse.com> <20210914153046.GB815@lst.de> In-Reply-To: From: Roman Skakun Date: Thu, 16 Sep 2021 12:40:28 +0300 Message-ID: Subject: Re: [PATCH] swiotlb: set IO TLB segment size via cmdline To: Stefano Stabellini Cc: Jan Beulich , Andrii Anisov , Roman Skakun , Jonathan Corbet , Thomas Bogendoerfer , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Konrad Rzeszutek Wilk , Boris Ostrovsky , Juergen Gross , Marek Szyprowski , Robin Murphy , "Paul E. McKenney" , Randy Dunlap , Andrew Morton , Thomas Gleixner , "Maciej W. Rozycki" , Muchun Song , Viresh Kumar , Peter Zijlstra , Lu Baolu , Mike Rapoport , Will Deacon , xen-devel@lists.xenproject.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-doc@vger.kernel.org, Linux Kernel Mailing List , iommu , Christoph Hellwig Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Stefano, > Also, Option 1 listed in the webpage seems to be a lot better. Any > reason you can't do that? Because that option both solves the problem > and increases performance. Yes, Option 1 is probably more efficient. But I use another platform under Xen without DMA adjustment functionality. I pinned this webpage only for example to describe the similar problem I ha= d. Cheers, Roman =D1=81=D1=80, 15 =D1=81=D0=B5=D0=BD=D1=82. 2021 =D0=B3. =D0=B2 04:51, Stefa= no Stabellini : > > On Tue, 14 Sep 2021, Christoph Hellwig wrote: > > On Tue, Sep 14, 2021 at 05:29:07PM +0200, Jan Beulich wrote: > > > I'm not convinced the swiotlb use describe there falls under "intende= d > > > use" - mapping a 1280x720 framebuffer in a single chunk? (As an aside= , > > > the bottom of this page is also confusing, as following "Then we can > > > confirm the modified swiotlb size in the boot log:" there is a log > > > fragment showing the same original size of 64Mb. > > > > It doesn't. We also do not add hacks to the kernel for whacky out > > of tree modules. > > Also, Option 1 listed in the webpage seems to be a lot better. Any > reason you can't do that? Because that option both solves the problem > and increases performance. -- Best Regards, Roman.