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 1B8BDECAAA1 for ; Fri, 28 Oct 2022 07:28:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230125AbiJ1H2V (ORCPT ); Fri, 28 Oct 2022 03:28:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53648 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230083AbiJ1H2T (ORCPT ); Fri, 28 Oct 2022 03:28:19 -0400 Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 808CB773AA; Fri, 28 Oct 2022 00:28:17 -0700 (PDT) Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.nyi.internal (Postfix) with ESMTP id 333A15C00DC; Fri, 28 Oct 2022 03:28:14 -0400 (EDT) Received: from imap51 ([10.202.2.101]) by compute3.internal (MEProxy); Fri, 28 Oct 2022 03:28:14 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arndb.de; h=cc :cc:content-type:date:date:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to; s=fm2; t=1666942094; x=1667028494; bh=J26rTTCqak 8NzMmZtDK4DJgyNSOzQar/SiCpEkw2BSI=; b=d01UbbMY0KK3xCKMyjPmdglyOs gML0qgOmGqtRNTlWFQ61bcd6w+MMLRDK0XyLuop7CExloWTeQV/g3Gtoq9veADnF nNF8a04GYsa7n73AqjNwbrK1mbzLblwqi8n8rI25QihRb47PRAdt3FzGoMm2xlqY qL99bmzviphREa7wpCEqJFbeDBxFYMfd7+wseEsjhRqiUG1L0ag6fZ52PDvG3wFT TbAyPJPay/draxkwpPBKRr45BcmyZgIYV2I1hwICplMxQUq1y5ICkoyRjpTq2XdB izWjgmSP1+62/IpuwxEb6y+xOSuyKEnbP56tFchzIDAptPpxPifVH+hG1ACA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:feedback-id :feedback-id:from:from:in-reply-to:in-reply-to:message-id :mime-version:references:reply-to:sender:subject:subject:to:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm3; t=1666942094; x=1667028494; bh=J26rTTCqak8NzMmZtDK4DJgyNSOz Qar/SiCpEkw2BSI=; b=OLuOC43SjqFfipyoGm0uM+YU8qcvst4bEcr2+UwC6PPN 2xTWvi5hoztjC4vBMx6NvghZdO6xP9XIdHDc5bPttWaX6JdKHvq/UKCLVRxujlnf zsXSzIXdQN24pjW1+55X3CMXMxp1yU0u69crGvWv6juFHX6Udiw0S1k8h0r1kTKO jK1egoRzzNAD2A+tH2QsPs0JUTLV50zBBM+uIO31kKu08MePu5dJmDoUVY/FcpeU JK+v1SNl36OXTxUc8jp3yBzH7dyR2dRBVyKEhhJtFnuZ4IhYrIh673K/X8ar6oLT Rlbcdn/rpLRUtGRUb9e2MrSiUEl/byWhWRu6/Gdk6w== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvgedrtdehgdduudekucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepofgfggfkjghffffhvfevufgtsehttdertderredtnecuhfhrohhmpedftehr nhguuceuvghrghhmrghnnhdfuceorghrnhgusegrrhhnuggsrdguvgeqnecuggftrfgrth htvghrnhepffehueegteeihfegtefhjefgtdeugfegjeelheejueethfefgeeghfektdek teffnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomheprg hrnhgusegrrhhnuggsrdguvg X-ME-Proxy: Feedback-ID: i56a14606:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id B484CB60089; Fri, 28 Oct 2022 03:28:11 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.7.0-alpha0-1087-g968661d8e1-fm-20221021.001-g968661d8 Mime-Version: 1.0 Message-Id: <6a0eff11-cda2-4790-bca8-f8de41981ea2@app.fastmail.com> In-Reply-To: References: <20220815071332.627393-1-yuzhao@google.com> <20220815071332.627393-9-yuzhao@google.com> Date: Fri, 28 Oct 2022 09:27:43 +0200 From: "Arnd Bergmann" To: "Maciej W. Rozycki" Cc: "Linus Torvalds" , "Matthew Wilcox" , "Peter Zijlstra" , "the arch/x86 maintainers" , "Yu Zhao" , "Andrew Morton" , "Andi Kleen" , "Aneesh Kumar" , "Catalin Marinas" , "Dave Hansen" , "Hillf Danton" , "Jens Axboe" , "Johannes Weiner" , "Jonathan Corbet" , "Mel Gorman" , "Michael Larabel" , "Michal Hocko" , "Mike Rapoport" , "Tejun Heo" , "Vlastimil Babka" , "Will Deacon" , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, page-reclaim@google.com, "Brian Geffon" , "Jan Alexander Steffens" , "Oleksandr Natalenko" , "Steven Barrett" , "Suleiman Souhlal" , "Daniel Byrne" , "Donald Carr" , =?UTF-8?Q?Holger_Hoffst=C3=A4tte?= , "Konstantin Kharlamov" , "Shuang Zhai" , "Sofia Trinh" , "Vaibhav Jain" Subject: Re: [PATCH v14 08/14] mm: multi-gen LRU: support page table walks Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 28, 2022, at 01:08, Maciej W. Rozycki wrote: > On Wed, 26 Oct 2022, Arnd Bergmann wrote: >> - For the special case of early ARMv6 hardware that has 32-bit >> atomics but not 64-bit ones, the kernel just falls back to >> CONFIG_GENERIC_ATOMIC64 and no cmpxchg64(). The same should work >> for an i486+SMP kernel. It's obviously slower, but most users >> can trivially avoid this by either running an i686 SMP kernel >> or an i486 UP kernel. > > You meant an M586TSC+ SMP kernel presumably (I have such a machine), but > otherwise I'd be fine with such an approach too. Sure. I just gave i686 as the example since that's already the baseline in 90% of the remaining x86-32 distros. Slackware, ALT and Mageia are notable exceptions that target i586, and some others already have separate installers for i486 and i686. The i586 distros all seem to have separate SMP/PAE kernels in addition to the minimal i586. Arnd