From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) by kanga.kvack.org (Postfix) with ESMTP id C52F08E0001 for ; Wed, 19 Dec 2018 01:56:27 -0500 (EST) Received: by mail-ed1-f69.google.com with SMTP id z10so15366012edz.15 for ; Tue, 18 Dec 2018 22:56:27 -0800 (PST) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id f27-v6si2125700ejh.100.2018.12.18.22.56.26 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 18 Dec 2018 22:56:26 -0800 (PST) Date: Wed, 19 Dec 2018 07:56:25 +0100 From: Michal Hocko Subject: Re: [PATCH] mm, page_alloc: clear zone_movable_pfn if the node doesn't have ZONE_MOVABLE Message-ID: <20181219065625.GC10480@dhcp22.suse.cz> References: <20181216125624.3416-1-richard.weiyang@gmail.com> <20181217102534.GF30879@dhcp22.suse.cz> <20181217141802.4bl4icg3mvwtmhqe@master> <20181218121451.GK30879@dhcp22.suse.cz> <20181218143943.ufuqzawibqyabzzl@master> <20181218144724.GM30879@dhcp22.suse.cz> <20181218202743.i5wvlzipzdl54fuq@master> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181218202743.i5wvlzipzdl54fuq@master> Sender: owner-linux-mm@kvack.org List-ID: To: Wei Yang Cc: linux-mm@kvack.org, akpm@linux-foundation.org, mgorman@techsingularity.net, osalvador@suse.de On Tue 18-12-18 20:27:43, Wei Yang wrote: [...] > BTW, would this eat lower zone's memory? For example, has less DMA32? Yes I think so. If the distribution should be even and some node(s) span only lower 32b address range then there is no other option than shrink the DMA32 zone. There is a note In the event, a node is too small to have both ZONE_NORMAL and ZONE_MOVABLE, kernelcore memory will take priority and other nodes will have a larger ZONE_MOVABLE. which explains that this might not be the case though. Btw. I have to say I quite do not like this interface not to mention the implementation. THere are users to rely on it though so we cannot remove it. There is a lot of room for cleanups there. -- Michal Hocko SUSE Labs