Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754216AbdDMONW (ORCPT ); Thu, 13 Apr 2017 10:13:22 -0400 Received: from mx2.suse.de ([195.135.220.15]:55370 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754107AbdDMONT (ORCPT ); Thu, 13 Apr 2017 10:13:19 -0400 Date: Thu, 13 Apr 2017 16:13:16 +0200 From: Michal Hocko To: Vlastimil Babka Cc: linux-mm@kvack.org, Andrew Morton , Mel Gorman , Andrea Arcangeli , Jerome Glisse , Reza Arbab , Yasuaki Ishimatsu , qiuxishi@huawei.com, Kani Toshimitsu , slaoub@gmail.com, Joonsoo Kim , Andi Kleen , David Rientjes , Daniel Kiper , Igor Mammedov , Vitaly Kuznetsov , LKML Subject: Re: [PATCH 5/9] mm, memory_hotplug: split up register_one_node Message-ID: <20170413141316.GC11795@dhcp22.suse.cz> References: <20170410110351.12215-1-mhocko@kernel.org> <20170410110351.12215-6-mhocko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2266 Lines: 59 On Thu 13-04-17 16:05:17, Vlastimil Babka wrote: > On 04/10/2017 01:03 PM, Michal Hocko wrote: > > From: Michal Hocko > > > > Memory hotplug (add_memory_resource) has to reinitialize node > > infrastructure if the node is offline (one which went through the > > complete add_memory(); remove_memory() cycle). That involves node > > registration to the kobj infrastructure (register_node), the proper > > association with cpus (register_cpu_under_node) and finally creation of > > node<->memblock symlinks (link_mem_sections). > > > > The last part requires to know node_start_pfn and node_spanned_pages > > which we currently have but a leter patch will postpone this > > initialization to the onlining phase which happens later. In fact we do > > not need to rely on the early pgdat initialization even now because the > > currently hot added pfn range is currently known. > > > > Split register_one_node into core which does all the common work for > > the boot time NUMA initialization and the hotplug (__register_one_node). > > register_one_node keeps the full initialization while hotplug calls > > __register_one_node and manually calls link_mem_sections for the proper > > range. > > > > This shouldn't introduce any functional change. > > > > Signed-off-by: Michal Hocko > > Acked-by: Vlastimil Babka Thanks! > nit: > > @@ -1387,7 +1387,22 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online) > > node_set_online(nid); > > > > if (new_node) { > > - ret = register_one_node(nid); > > + unsigned long start_pfn = start >> PAGE_SHIFT; > > + unsigned long nr_pages = size >> PAGE_SHIFT; > > + > > + ret = __register_one_node(nid); > > + if (ret) > > + goto register_fail; > > + > > + /* > > + * link memory sections under this node. This is already > > + * done when creatig memory section in register_new_memory > > + * but that depends to have the node registered so offline > > + * nodes have to go through register_node. > > + * TODO clean up this mess. > > Is this a work-in-progress or final TODO? :) I do not plan to address it in this series, but I will revisit it later. There are more like this in other patches. -- Michal Hocko SUSE Labs