From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751592AbaHQLI0 (ORCPT ); Sun, 17 Aug 2014 07:08:26 -0400 Received: from mail-qc0-f175.google.com ([209.85.216.175]:63871 "EHLO mail-qc0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751211AbaHQLIZ (ORCPT ); Sun, 17 Aug 2014 07:08:25 -0400 Date: Sun, 17 Aug 2014 07:08:21 -0400 From: Tejun Heo To: Xishi Qiu Cc: Andrew Morton , Tang Chen , Zhang Yanfei , Wen Congyang , "Rafael J. Wysocki" , "H. Peter Anvin" , Linux MM , LKML Subject: Re: [PATCH] mem-hotplug: let memblock skip the hotpluggable memory regions in __next_mem_range() Message-ID: <20140817110821.GM9305@htj.dyndns.org> References: <53E8C5AA.5040506@huawei.com> <20140816130456.GH9305@htj.dyndns.org> <53EF6C79.3000603@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <53EF6C79.3000603@huawei.com> 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 Hello, On Sat, Aug 16, 2014 at 10:36:41PM +0800, Xishi Qiu wrote: > numa_clear_node_hotplug()? There is only numa_clear_kernel_node_hotplug(). Yeah, that one. > If we don't clear hotpluggable flag in free_low_memory_core_early(), the > memory which marked hotpluggable flag will not free to buddy allocator. > Because __next_mem_range() will skip them. > > free_low_memory_core_early > for_each_free_mem_range > for_each_mem_range > __next_mem_range Ah, okay, so the patch fixes __next_mem_range() and thus makes free_low_memory_core_early() to skip hotpluggable regions unlike before. Please explain things like that in the changelog. Also, what's its relationship with numa_clear_kernel_node_hotplug()? Do we still need them? If so, what are the different roles that these two separate places serve? Thanks. -- tejun