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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 AB70FC433E0 for ; Mon, 15 Mar 2021 13:51:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 15B0264E83 for ; Mon, 15 Mar 2021 13:51:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 15B0264E83 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 69B016B0036; Mon, 15 Mar 2021 09:51:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 649C56B006C; Mon, 15 Mar 2021 09:51:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 511876B0070; Mon, 15 Mar 2021 09:51:19 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0192.hostedemail.com [216.40.44.192]) by kanga.kvack.org (Postfix) with ESMTP id 300CC6B0036 for ; Mon, 15 Mar 2021 09:51:19 -0400 (EDT) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id B6B07181AF5E1 for ; Mon, 15 Mar 2021 13:51:18 +0000 (UTC) X-FDA: 77922245436.23.D971AA5 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf21.hostedemail.com (Postfix) with ESMTP id 0BFE5E01F83B for ; Mon, 15 Mar 2021 13:45:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=vX11bsGcJE0CRePOS5HuSnKaopIkgIWxWo8E8FVQGL8=; b=oQ69t1xbTPN6zyN+S04ZNJkw+1 NHEq0XYigCUv7yk6ZSAuVHwDlAK7Y6Doa2HYx1gTelmAJcpuvZf5R7Esrm2Fkc3v8923U3B5YIf3a +WP6njTaJgADtltqncxuHYiEHjoJQHnoQMeqq7qzrd/TrOdVRTVx5gdVykRS4nzW5hgA8wkALDaJ1 QOeAca+77u8HF9PRx/8d66M2YZut228mYetTSnOL3tHYHD55D3f8/QoPRLr5NzX16+KJKJ1+l2U7h V8f4fJ0tZAkO0I/GGeHWAOeuaIzH3+K94n9N8v+CY5hKgvOMZTAAm8zMR5TiQtRyewS9sIy/Q6DhV xaOi0Usw==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lLnWu-000Fop-2q; Mon, 15 Mar 2021 13:45:14 +0000 Date: Mon, 15 Mar 2021 13:45:08 +0000 From: Matthew Wilcox To: "Kirill A. Shutemov" Cc: Hugh Dickins , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v4 00/25] Page folios Message-ID: <20210315134508.GX2577561@casper.infradead.org> References: <20210305041901.2396498-1-willy@infradead.org> <20210313123658.ad2dcf79a113a8619c19c33b@linux-foundation.org> <20210315115501.7rmzaan2hxsqowgq@box> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210315115501.7rmzaan2hxsqowgq@box> X-Stat-Signature: tzh4iuaang4ybhuaz6n9mwj178bckfby X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 0BFE5E01F83B Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf21; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1615815933-686598 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Mar 15, 2021 at 02:55:01PM +0300, Kirill A. Shutemov wrote: > I'm with Matthew on this. I would really want to drop the number of places > where we call compoud_head(). I hope we can get rid of the page flag > policy hack I made. I can't see that far ahead too clearly, but I do think that at some point we'll actually distinguish between folio flags and page flags. For example, we won't have a FolioHWPoison, because we won't keep a folio together if one page in it has become defective. Nor will we have a PageUptodate because we'll only care about whether a folio is uptodate. And at that point, we won't want page flag policies.