From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: mmotm 2015-01-22-15-04: qemu failure due to 'mm: memcontrol: remove unnecessary soft limit tree node test' Date: Fri, 23 Jan 2015 12:33:33 -0800 Message-ID: <54C2B01D.4070303@roeck-us.net> References: <54c1822d.RtdGfWPekQVAw8Ly%akpm@linux-foundation.org> <20150123050802.GB22751@roeck-us.net> <20150123141817.GA22926@phnom.home.cmpxchg.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: akpm@linux-foundation.org, mm-commits@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-next@vger.kernel.org, sfr@canb.auug.org.au, mhocko@suse.cz To: Christoph Lameter , Johannes Weiner Return-path: Received: from bh-25.webhostbox.net ([208.91.199.152]:42478 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751694AbbAWUdq (ORCPT ); Fri, 23 Jan 2015 15:33:46 -0500 Received: from mailnull by bh-25.webhostbox.net with sa-checked (Exim 4.82) (envelope-from ) id 1YEkvK-003UOc-Un for linux-fsdevel@vger.kernel.org; Fri, 23 Jan 2015 20:33:47 +0000 In-Reply-To: Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On 01/23/2015 12:20 PM, Christoph Lameter wrote: > On Fri, 23 Jan 2015, Johannes Weiner wrote: > >> struct mem_cgroup_tree_per_node *rtpn; >> struct mem_cgroup_tree_per_zone *rtpz; >> - int tmp, node, zone; >> + int node, zone; >> >> for_each_node(node) { > > Do for_each_online_node(node) { > > instead? > Wouldn't that have unintended consequences ? So far rb tree nodes are allocated even if a node not online; the above would change that. Are you saying it is unnecessary to initialize rb tree nodes if the node is not online ? Not that I have any idea what is correct, it just seems odd that the existing code would do all this allocation if it is not necessary. Guenter