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 ACDACC00144 for ; Mon, 1 Aug 2022 22:25:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235305AbiHAWZt (ORCPT ); Mon, 1 Aug 2022 18:25:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235332AbiHAWZp (ORCPT ); Mon, 1 Aug 2022 18:25:45 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id F0B3143E62 for ; Mon, 1 Aug 2022 15:25:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1659392744; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=JuDYx7rY0J8nhH7yYroLa1iYucx7uxXCdAdFRarEXz8=; b=H71KrKltcJ8w9Sv/dMkhi618ocoDzgSh8tMUnL9riNL+HCJegMxJgOZfDSV7CD+hyPUkJj nanoqkTZAWUSgiATHqlWWDf9f1oqX46rD/+DrHqrxXUjB95lVmEycWb/2tnraC2rnjtvkH qLdestzfu8Yk/VKL5z/ctrBNsn0gQdU= Received: from mail-qk1-f200.google.com (mail-qk1-f200.google.com [209.85.222.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-103-kx7v_k3eP2qOpGuXXXaW2g-1; Mon, 01 Aug 2022 18:25:42 -0400 X-MC-Unique: kx7v_k3eP2qOpGuXXXaW2g-1 Received: by mail-qk1-f200.google.com with SMTP id az14-20020a05620a170e00b006b666c4627bso10365879qkb.23 for ; Mon, 01 Aug 2022 15:25:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=JuDYx7rY0J8nhH7yYroLa1iYucx7uxXCdAdFRarEXz8=; b=mEbEnpR0wU5QoJF2o0d6n+nzj5I4dmcecXOI13T6Ar1G/7FyvmDPleZThm3Uzl6OGi dTOe9K4fxrfHQMS+qfDAzILn7WcPmz8Dj+abqY8mYvnaxIwvS6XOjE8bY02+byGVnhlI WqpVJY9yFpDVBwxivOqPFFYrKn2kJWpZrJJ2EyzqPah48DPVFFLunQ+n2nB5IdtIu60a s2BHVvgWzXExMNZcRYtvzJzhVOWjURcLnRH80yUqJl0mvQXZrrbXiPgzsez7+MZYZYQ/ Cn4Z2SUnGnAS/bCEOYEiziqQgxzYlVwEZWQM2EAl9s9Zb6E2t8MjL5+P5YP/kU8fRwb9 U8Tw== X-Gm-Message-State: AJIora9cDEld1h99mnu6vdmX2Xatry/zILWYOvwIgR+o/FV73zXGkgSd ep/rpEwqm1O+gGhZK9XRH2W0Ahvf/0lTgIdtV1Mz4mP9ZL/z2Tp1vOdv09XMJ0OgSVIJS9sGD4h ueBz66se/kBq4Xqa1E6edyNei X-Received: by 2002:ac8:7fcd:0:b0:31f:393a:7320 with SMTP id b13-20020ac87fcd000000b0031f393a7320mr16130503qtk.11.1659392742428; Mon, 01 Aug 2022 15:25:42 -0700 (PDT) X-Google-Smtp-Source: AGRyM1s9QavQ6UCl89HWn9HB+y/pVPGLyyjDb7YjYhagDxykylUdwhjqBKKeaWnrBZ77w3N/uo9SQA== X-Received: by 2002:ac8:7fcd:0:b0:31f:393a:7320 with SMTP id b13-20020ac87fcd000000b0031f393a7320mr16130479qtk.11.1659392742210; Mon, 01 Aug 2022 15:25:42 -0700 (PDT) Received: from xz-m1.local (bras-base-aurron9127w-grc-35-70-27-3-10.dsl.bell.ca. [70.27.3.10]) by smtp.gmail.com with ESMTPSA id dm52-20020a05620a1d7400b006a6ab259261sm9120434qkb.29.2022.08.01.15.25.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 Aug 2022 15:25:41 -0700 (PDT) Date: Mon, 1 Aug 2022 18:25:40 -0400 From: Peter Xu To: "Huang, Ying" Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrea Arcangeli , Andrew Morton , "Kirill A . Shutemov" , Nadav Amit , Hugh Dickins , David Hildenbrand , Vlastimil Babka , Andi Kleen Subject: Re: [PATCH RFC 0/4] mm: Remember young bit for migration entries Message-ID: References: <20220729014041.21292-1-peterx@redhat.com> <87pmhkjzo7.fsf@yhuang6-desk2.ccr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <87pmhkjzo7.fsf@yhuang6-desk2.ccr.corp.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 01, 2022 at 01:33:28PM +0800, Huang, Ying wrote: > If my understanding were correct, max_swapfile_size() provides a > mechanism to identify the available bits with swp_entry_t and swap PTE > considered. We may take advantage of that? That's an interesting trick, I'll have a closer look, thanks for the pointer! > > And according to commit 377eeaa8e11f ("x86/speculation/l1tf: Limit swap > file size to MAX_PA/2"), the highest bit of swap offset needs to be 0 if > L1TF mitigation is enabled. > > Cced Andi for confirmation. Yeah it'll be great to have a confirmation, hopefully max_swapfile_size() should have covered that case. -- Peter Xu