From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f199.google.com (mail-wr0-f199.google.com [209.85.128.199]) by kanga.kvack.org (Postfix) with ESMTP id 932B46B002B for ; Fri, 9 Feb 2018 05:51:36 -0500 (EST) Received: by mail-wr0-f199.google.com with SMTP id 17so4333532wrm.10 for ; Fri, 09 Feb 2018 02:51:36 -0800 (PST) Received: from mail-sor-f41.google.com (mail-sor-f41.google.com. [209.85.220.41]) by mx.google.com with SMTPS id o26sor1245125edi.29.2018.02.09.02.51.34 for (Google Transport Security); Fri, 09 Feb 2018 02:51:35 -0800 (PST) Date: Fri, 9 Feb 2018 13:51:32 +0300 From: "Kirill A. Shutemov" Subject: Re: [PATCH] mm: Split page_type out from _map_count Message-ID: <20180209105132.hhkjoijini3f74fz@node.shutemov.name> References: <20180207213047.6148-1-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180207213047.6148-1-willy@infradead.org> Sender: owner-linux-mm@kvack.org List-ID: To: Matthew Wilcox Cc: linux-mm@kvack.org, Matthew Wilcox On Wed, Feb 07, 2018 at 01:30:47PM -0800, Matthew Wilcox wrote: > From: Matthew Wilcox > > We're already using a union of many fields here, so stop abusing the > _map_count and make page_type its own field. That implies renaming some > of the machinery that creates PageBuddy, PageBalloon and PageKmemcg; > bring back the PG_buddy, PG_balloon and PG_kmemcg names. Sounds reasonable to me. > Also, the special values don't need to be (and probably shouldn't be) powers > of two, so renumber them to just start at -128. Are you sure about this? Is it guarantee that we would not need in the future PG_buddy|PG_kmemcg for instance? I guess we may want to make it a bitfield. In negative space it's kinda interesting. :) -- Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org