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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 039A8C43334 for ; Tue, 4 Sep 2018 14:00:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A374820843 for ; Tue, 4 Sep 2018 14:00:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A374820843 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=cs.rutgers.edu Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727327AbeIDSZn (ORCPT ); Tue, 4 Sep 2018 14:25:43 -0400 Received: from mail-qt0-f195.google.com ([209.85.216.195]:38926 "EHLO mail-qt0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726281AbeIDSZn (ORCPT ); Tue, 4 Sep 2018 14:25:43 -0400 Received: by mail-qt0-f195.google.com with SMTP id o15-v6so4025238qtk.6 for ; Tue, 04 Sep 2018 07:00:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version; bh=6d8oK52oDU3c4v/LizU2pC/wmIlrWoBqw7/YfyPTHLs=; b=ul7+H1JYJuPCEW3lkYDZVSbYRHSKajuL63Unys73NMMLgrWXbkqR+sp5c3FBjnC3QC wTZsqa535KtiQhMKvNUA56woUGOgA9OUXYB9K2szgM+0gpGfoxt24sQietwaG94zEGQn lY33POBW6eanevXqJMy4CRah5HMcpvf20+EPtCEsciZE9ouxOFPK7F9/XERXKpidcAZk Nu/msEKk9U6NpSEpGxdsANmJsxwva2SuBtyyEoiO+WDpzA/KCeR+EkOqDQhl1lpLTb09 OacPOzw6+yXvplI0i//RWKxoMK14seCRYyL44GAsDp1DltCLDL6o2Be04bB3NPvPpvPg /25g== X-Gm-Message-State: APzg51Bp65rcNwdmYcVRURHk5CYblKq8G25CmStbDANC+AjyEIjmMSqv 0O5VF55H9qZ9HwGnkBf0wudrUQ== X-Google-Smtp-Source: ANB0VdZYojNcAYtiAoXndRLQgxKSMS/OqZwdKHTex0VP68m71/+XloKJKBUnyRYjm0zFRA70f09jrQ== X-Received: by 2002:aed:3b32:: with SMTP id p47-v6mr30490161qte.13.1536069628090; Tue, 04 Sep 2018 07:00:28 -0700 (PDT) Received: from [172.25.138.20] (pool-128-6-37-67.nat.rutgers.edu. [128.6.37.67]) by smtp.gmail.com with ESMTPSA id q18-v6sm12368210qtk.57.2018.09.04.07.00.26 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 04 Sep 2018 07:00:26 -0700 (PDT) From: "Zi Yan" To: "Kirill A. Shutemov" , "Peter Xu" Cc: linux-kernel@vger.kernel.org, "Andrea Arcangeli" , "Andrew Morton" , "Kirill A. Shutemov" , "Michal Hocko" , "Huang Ying" , "Dan Williams" , "Naoya Horiguchi" , "=?utf-8?b?SsOpcsO0bWU=?= Glisse" , "Aneesh Kumar K.V" , "Konstantin Khlebnikov" , "Souptick Joarder" , linux-mm@kvack.org Subject: Re: [PATCH] mm: hugepage: mark splitted page dirty when needed Date: Tue, 04 Sep 2018 10:00:28 -0400 X-Mailer: MailMate (2.0BETAr6116) Message-ID: In-Reply-To: <20180904080115.o2zj4mlo7yzjdqfl@kshutemo-mobl1> References: <20180904075510.22338-1-peterx@redhat.com> <20180904080115.o2zj4mlo7yzjdqfl@kshutemo-mobl1> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=_MailMate_00AD4CDF-164D-44D4-9FF2-9BB7F3A78B9B_="; micalg=pgp-sha512; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 3156 and 4880). --=_MailMate_00AD4CDF-164D-44D4-9FF2-9BB7F3A78B9B_= Content-Type: text/plain On 4 Sep 2018, at 4:01, Kirill A. Shutemov wrote: > On Tue, Sep 04, 2018 at 03:55:10PM +0800, Peter Xu wrote: >> When splitting a huge page, we should set all small pages as dirty if >> the original huge page has the dirty bit set before. Otherwise we'll >> lose the original dirty bit. > > We don't lose it. It got transfered to struct page flag: > > if (pmd_dirty(old_pmd)) > SetPageDirty(page); > Plus, when split_huge_page_to_list() splits a THP, its subroutine __split_huge_page() propagates the dirty bit in the head page flag to all subpages in __split_huge_page_tail(). -- Best Regards Yan Zi --=_MailMate_00AD4CDF-164D-44D4-9FF2-9BB7F3A78B9B_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- Comment: GPGTools - https://gpgtools.org iQEcBAEBCgAGBQJbjo/8AAoJEEGLLxGcTqbMOQwH/0Dqm8efQO5JjwZLEfJ72RER Hi/IEMJNxCdcWacrHwUTlEcDc8Si36b83nU5ja0FZLMtT6erIFoprzPcY+0AeMkP FIoDqREsQUd/1rZS5/w5xzWZP53tBKXGwJ3Du6r2OFv11+O+UdGPFBTgRMafg15h dZ1UPQ+gZWV0jJ5/BDwHVkA7fLSKvOwlLKeIUOonaOZI/WkU7VA7jT3TAoaZPvYD W9rf4JmEY0aZi69K5krMidhXTvn7o5GQ0f7bLrXWuxGDtlDCsZWGwrTpTTOSPomM mJ8Nf85vsXdUwkM0VAtMcARJ4EffLfaN1OdNeXxh/7stS8x85jo81OWNEGSdXaU= =I4oJ -----END PGP SIGNATURE----- --=_MailMate_00AD4CDF-164D-44D4-9FF2-9BB7F3A78B9B_=--