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 A98E0C433E6 for ; Wed, 17 Mar 2021 17:46:36 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3664264EF3 for ; Wed, 17 Mar 2021 17:46:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3664264EF3 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 77B0B6B006E; Wed, 17 Mar 2021 13:46:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7184E6B0070; Wed, 17 Mar 2021 13:46:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5B9456B0071; Wed, 17 Mar 2021 13:46:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0072.hostedemail.com [216.40.44.72]) by kanga.kvack.org (Postfix) with ESMTP id 3F06F6B006E for ; Wed, 17 Mar 2021 13:46:35 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id DF7C7180AD838 for ; Wed, 17 Mar 2021 17:46:34 +0000 (UTC) X-FDA: 77930095908.29.E943AE3 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf13.hostedemail.com (Postfix) with ESMTP id 39DE4E079859 for ; Wed, 17 Mar 2021 17:14:44 +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=yo6Fi9VPbozhR4/XkrldehgVPuWGAklwU7qbAjO38qQ=; b=Ztpw7xml643pqS6iyfntpjWSUP XSi+NpT+KK5byJXLPP5aI9TfIlIs470+JZq3+fiEQqeH/nsZ6d+0VW4G3tA1Zs2MWzN8g6bDG4Edh Ej9D8VUkAS/U5KNj1cHLYsX5+Ra8VVIln34KFq4as8vjAw3WLHplU+Nt2DBSgWPJKv/5PflBzaJFs KrR7w4iSeNYy/11SyHouk+QdY/MJSEB6AapmzCyWRzrSs8UXUgM+BT5GMLUoeKoqF4GhhNECd0k7a p3ZxqILzaZ7vz5EiWYFj8jHWE+MojeTiK/lmWv4E7rCVrP7GXweqLdYQNSasdkeGysVIdrg+A2aR7 U9pd9/Sw==; Received: from hch by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lMZkK-001tiT-NJ; Wed, 17 Mar 2021 17:14:17 +0000 Date: Wed, 17 Mar 2021 17:14:12 +0000 From: Christoph Hellwig To: "Matthew Wilcox (Oracle)" Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v4 01/25] mm: Introduce struct folio Message-ID: <20210317171412.GA451661@infradead.org> References: <20210305041901.2396498-1-willy@infradead.org> <20210305041901.2396498-2-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210305041901.2396498-2-willy@infradead.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-Stat-Signature: 9irsymzob1mxwuo1e93r14pubdyemygq X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 39DE4E079859 Received-SPF: none (casper.srs.infradead.org>: No applicable sender policy available) receiver=imf13; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616001284-675483 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 Fri, Mar 05, 2021 at 04:18:37AM +0000, Matthew Wilcox (Oracle) wrote: > +/* > + * A struct folio is either a base (order-0) page or the head page of > + * a compound page. > + */ Hmm. While that comment seems to be true I'm not sure it is the essence. Maybe it should be more framed in terms of "A folio represents a contigously allocated chunk of memory.." and then extend it with the categories of state and operations performed on the folio while those get added. The above statement can still remain as a low-level explanation, maybe moved to the page member instead of the type itself.