From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757314Ab0JTD1X (ORCPT ); Tue, 19 Oct 2010 23:27:23 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:41884 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755916Ab0JTD1W (ORCPT ); Tue, 19 Oct 2010 23:27:22 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Wed, 20 Oct 2010 12:21:44 +0900 From: KAMEZAWA Hiroyuki To: Greg Thelen Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, containers@lists.osdl.org, Andrea Righi , Balbir Singh , Daisuke Nishimura , Minchan Kim , Ciju Rajan K , David Rientjes Subject: [PATCH][memcg+dirtylimit] Fix overwriting global vm dirty limit setting by memcg (Re: [PATCH v3 00/11] memcg: per cgroup dirty page accounting Message-Id: <20101020122144.47f2b60b.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <1287448784-25684-1-git-send-email-gthelen@google.com> References: <1287448784-25684-1-git-send-email-gthelen@google.com> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 3.0.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org One bug fix here. == From: KAMEZAWA Hiroyuki Now, at calculating dirty limit, vm_dirty_param() is called. This function returns dirty-limit related parameters considering memory cgroup settings. Now, assume that vm_dirty_bytes=100M (global dirty limit) and memory cgroup has 1G of pages and 40 dirty_ratio, dirtyable memory is 500MB. In this case, global_dirty_limits will consider dirty_limt as 500 *0.4 = 200MB. This is bad...memory cgroup is not back door. This patch limits the return value of vm_dirty_param() considring global settings. Signed-off-by: KAMEZAWA Hiroyuki --- include/linux/memcontrol.h | 4 ++-- mm/memcontrol.c | 29 ++++++++++++++++++++++++++++- mm/page-writeback.c | 2 +- 3 files changed, 31 insertions(+), 4 deletions(-) Index: dirty_limit_new/mm/memcontrol.c =================================================================== --- dirty_limit_new.orig/mm/memcontrol.c +++ dirty_limit_new/mm/memcontrol.c @@ -1171,9 +1171,10 @@ static void __mem_cgroup_dirty_param(str * can be moved after our access and writeback tends to take long time. At * least, "memcg" will not be freed while holding rcu_read_lock(). */ -void vm_dirty_param(struct vm_dirty_param *param) +void vm_dirty_param(struct vm_dirty_param *param, unsigned long mem) { struct mem_cgroup *memcg; + u64 limit, bglimit; if (mem_cgroup_disabled()) { global_vm_dirty_param(param); @@ -1183,6 +1184,32 @@ void vm_dirty_param(struct vm_dirty_para rcu_read_lock(); memcg = mem_cgroup_from_task(current); __mem_cgroup_dirty_param(param, memcg); + /* + * A limitation under memory cgroup is under global vm, too. + */ + if (vm_dirty_ratio) + limit = mem * vm_dirty_ratio / 100; + else + limit = vm_dirty_bytes; + if (param->dirty_ratio) { + param->dirty_bytes = mem * param->dirty_ratio / 100; + param->dirty_ratio = 0; + } + if (param->dirty_bytes > limit) + param->dirty_bytes = limit; + + if (dirty_background_ratio) + bglimit = mem * dirty_background_ratio / 100; + else + bglimit = dirty_background_bytes; + + if (param->dirty_background_ratio) { + param->dirty_background_bytes = + mem * param->dirty_background_ratio /100; + param->dirty_background_ratio = 0; + } + if (param->dirty_background_bytes > bglimit) + param->dirty_background_bytes = bglimit; rcu_read_unlock(); } Index: dirty_limit_new/include/linux/memcontrol.h =================================================================== --- dirty_limit_new.orig/include/linux/memcontrol.h +++ dirty_limit_new/include/linux/memcontrol.h @@ -171,7 +171,7 @@ static inline void mem_cgroup_dec_page_s } bool mem_cgroup_has_dirty_limit(void); -void vm_dirty_param(struct vm_dirty_param *param); +void vm_dirty_param(struct vm_dirty_param *param, u64 mem); s64 mem_cgroup_page_stat(enum mem_cgroup_nr_pages_item item); unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, @@ -360,7 +360,7 @@ static inline bool mem_cgroup_has_dirty_ return false; } -static inline void vm_dirty_param(struct vm_dirty_param *param) +static inline void vm_dirty_param(struct vm_dirty_param *param, u64 mem) { global_vm_dirty_param(param); } Index: dirty_limit_new/mm/page-writeback.c =================================================================== --- dirty_limit_new.orig/mm/page-writeback.c +++ dirty_limit_new/mm/page-writeback.c @@ -466,7 +466,7 @@ void global_dirty_limits(unsigned long * struct task_struct *tsk; struct vm_dirty_param dirty_param; - vm_dirty_param(&dirty_param); + vm_dirty_param(&dirty_param, avialable_memory); if (dirty_param.dirty_bytes) dirty = DIV_ROUND_UP(dirty_param.dirty_bytes, PAGE_SIZE);