Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932396Ab2ENUOp (ORCPT ); Mon, 14 May 2012 16:14:45 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:58200 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932317Ab2ENUOn (ORCPT ); Mon, 14 May 2012 16:14:43 -0400 Date: Mon, 14 May 2012 13:14:38 -0700 From: Tejun Heo To: KAMEZAWA Hiroyuki Cc: "linux-mm@kvack.org" , "cgroups@vger.kernel.org" , Michal Hocko , Johannes Weiner , Frederic Weisbecker , Han Ying , Glauber Costa , "Aneesh Kumar K.V" , Andrew Morton , Hiroyuki Kamezawa , Linux Kernel Subject: Re: [PATCH v3 4/6] memcg: move charges to root cgroup if use_hierarchy=0. Message-ID: <20120514201438.GI2366@google.com> References: <4FACDED0.3020400@jp.fujitsu.com> <4FACE0A2.30608@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4FACE0A2.30608@jp.fujitsu.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1653 Lines: 47 On Fri, May 11, 2012 at 06:49:22PM +0900, KAMEZAWA Hiroyuki wrote: > @@ -3351,9 +3339,8 @@ int mem_cgroup_move_hugetlb_parent(int idx, struct cgroup *cgroup, > struct page_cgroup *pc; > int csize, ret = 0; > struct res_counter *fail_res; > - struct cgroup *pcgrp = cgroup->parent; > - struct mem_cgroup *parent = mem_cgroup_from_cont(pcgrp); > struct mem_cgroup *memcg = mem_cgroup_from_cont(cgroup); > + struct mem_cgroup *parent = parent_mem_cgroup(memcg); > struct res_counter *counter; > > if (!get_page_unless_zero(page)) > @@ -3366,13 +3353,11 @@ int mem_cgroup_move_hugetlb_parent(int idx, struct cgroup *cgroup, > > csize = PAGE_SIZE << compound_order(page); > /* If parent->use_hierarchy == 0, we need to charge parent */ > - if (!parent->use_hierarchy) { > - ret = res_counter_charge(&parent->hugepage[idx], > - csize, &fail_res); > - if (ret) { > - ret = -EBUSY; > - goto err_out; > - } > + if (!parent) { > + parent = root_mem_cgroup; > + /* root has no limit */ > + res_counter_charge_nofail(&parent->hugepage[idx], > + csize, &fail_res); > } > counter = &memcg->hugepage[idx]; > res_counter_uncharge_until(counter, counter->parent, csize); This function can simply return 0 now, so no point in having int return. Make it return void? Also, follow-up patches to cleanup -ENOMEM failure handling in the callers would be nice. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/