From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754832Ab1A1Ez3 (ORCPT ); Thu, 27 Jan 2011 23:55:29 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:51487 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754772Ab1A1Ez2 (ORCPT ); Thu, 27 Jan 2011 23:55:28 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Fri, 28 Jan 2011 13:49:02 +0900 From: KAMEZAWA Hiroyuki To: Daisuke Nishimura Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "hannes@cmpxchg.org" , "balbir@linux.vnet.ibm.com" Subject: Re: [BUGFIX][PATCH 1/4] memcg: fix limit estimation at reclaim for hugepage Message-Id: <20110128134902.5845b507.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110128134019.27abcfe2.nishimura@mxp.nes.nec.co.jp> References: <20110128122229.6a4c74a2.kamezawa.hiroyu@jp.fujitsu.com> <20110128122449.e4bb0e5f.kamezawa.hiroyu@jp.fujitsu.com> <20110128134019.27abcfe2.nishimura@mxp.nes.nec.co.jp> 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 On Fri, 28 Jan 2011 13:40:19 +0900 Daisuke Nishimura wrote: > On Fri, 28 Jan 2011 12:24:49 +0900 > KAMEZAWA Hiroyuki wrote: > > > From: KAMEZAWA Hiroyuki > > > > Current memory cgroup's code tends to assume page_size == PAGE_SIZE > > and arrangement for THP is not enough yet. > > > > This is one of fixes for supporing THP. This adds > > mem_cgroup_check_margin() and checks whether there are required amount of > > free resource after memory reclaim. By this, THP page allocation > > can know whether it really succeeded or not and avoid infinite-loop > > and hangup. > > > > Total fixes for do_charge()/reclaim memory will follow this patch. > > > > Signed-off-by: KAMEZAWA Hiroyuki > > This patch looks good to me, but some nitpicks. > > > --- > > include/linux/res_counter.h | 11 +++++++++++ > > mm/memcontrol.c | 25 ++++++++++++++++++++++++- > > 2 files changed, 35 insertions(+), 1 deletion(-) > > > > Index: mmotm-0125/include/linux/res_counter.h > > =================================================================== > > --- mmotm-0125.orig/include/linux/res_counter.h > > +++ mmotm-0125/include/linux/res_counter.h > > @@ -182,6 +182,17 @@ static inline bool res_counter_check_und > > return ret; > > } > > > > +static inline s64 res_counter_check_margin(struct res_counter *cnt) > > +{ > > + s64 ret; > > + unsigned long flags; > > + > > + spin_lock_irqsave(&cnt->lock, flags); > > + ret = cnt->limit - cnt->usage; > > + spin_unlock_irqrestore(&cnt->lock, flags); > > + return ret; > > +} > > + > > static inline bool res_counter_check_under_soft_limit(struct res_counter *cnt) > > { > > bool ret; > > Index: mmotm-0125/mm/memcontrol.c > > =================================================================== > > --- mmotm-0125.orig/mm/memcontrol.c > > +++ mmotm-0125/mm/memcontrol.c > > @@ -1111,6 +1111,22 @@ static bool mem_cgroup_check_under_limit > > return false; > > } > > > > +static s64 mem_cgroup_check_margin(struct mem_cgroup *mem) > > +{ > > + s64 mem_margin; > > + > > + if (do_swap_account) { > > + s64 memsw_margin; > > + > > + mem_margin = res_counter_check_margin(&mem->res); > > + memsw_margin = res_counter_check_margin(&mem->memsw); > > + if (mem_margin > memsw_margin) > > + mem_margin = memsw_margin; > > + } else > > + mem_margin = res_counter_check_margin(&mem->res); > > + return mem_margin; > > +} > > + > How about > > mem_margin = res_counter_check_margin(&mem->res); > if (do_swap_account) > memsw_margin = res_counter_check_margin(&mem->memsw); > else > memsw_margin = RESOURCE_MAX; > > return min(mem_margin, memsw_margin); > > ? > I think using min() makes it more clear what this function does. > Ok. > > static unsigned int get_swappiness(struct mem_cgroup *memcg) > > { > > struct cgroup *cgrp = memcg->css.cgroup; > > @@ -1853,7 +1869,14 @@ static int __mem_cgroup_do_charge(struct > > * Check the limit again to see if the reclaim reduced the > > * current usage of the cgroup before giving up > > */ > > - if (ret || mem_cgroup_check_under_limit(mem_over_limit)) > > + if (mem_cgroup_check_margin(mem_over_limit) >= csize) > > + return CHARGE_RETRY; > > + > > + /* > > + * If the charge size is a PAGE_SIZE, it's not hopeless while > > + * we can reclaim a page. > > + */ > > + if (csize == PAGE_SIZE && ret) > > return CHARGE_RETRY; > > > > /* > > > checkpatch complains some whitespace warnings. > will fix soon. -Kame From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id 9A0AC8D0039 for ; Thu, 27 Jan 2011 23:55:39 -0500 (EST) Received: from m2.gw.fujitsu.co.jp (unknown [10.0.50.72]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id B108D3EE0AE for ; Fri, 28 Jan 2011 13:55:26 +0900 (JST) Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 9970A45DE4E for ; Fri, 28 Jan 2011 13:55:26 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 8257245DE4D for ; Fri, 28 Jan 2011 13:55:26 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 751F01DB803A for ; Fri, 28 Jan 2011 13:55:26 +0900 (JST) Received: from m107.s.css.fujitsu.com (m107.s.css.fujitsu.com [10.249.87.107]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 3C7B81DB8038 for ; Fri, 28 Jan 2011 13:55:26 +0900 (JST) Date: Fri, 28 Jan 2011 13:49:02 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [BUGFIX][PATCH 1/4] memcg: fix limit estimation at reclaim for hugepage Message-Id: <20110128134902.5845b507.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110128134019.27abcfe2.nishimura@mxp.nes.nec.co.jp> References: <20110128122229.6a4c74a2.kamezawa.hiroyu@jp.fujitsu.com> <20110128122449.e4bb0e5f.kamezawa.hiroyu@jp.fujitsu.com> <20110128134019.27abcfe2.nishimura@mxp.nes.nec.co.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Daisuke Nishimura Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "hannes@cmpxchg.org" , "balbir@linux.vnet.ibm.com" List-ID: On Fri, 28 Jan 2011 13:40:19 +0900 Daisuke Nishimura wrote: > On Fri, 28 Jan 2011 12:24:49 +0900 > KAMEZAWA Hiroyuki wrote: > > > From: KAMEZAWA Hiroyuki > > > > Current memory cgroup's code tends to assume page_size == PAGE_SIZE > > and arrangement for THP is not enough yet. > > > > This is one of fixes for supporing THP. This adds > > mem_cgroup_check_margin() and checks whether there are required amount of > > free resource after memory reclaim. By this, THP page allocation > > can know whether it really succeeded or not and avoid infinite-loop > > and hangup. > > > > Total fixes for do_charge()/reclaim memory will follow this patch. > > > > Signed-off-by: KAMEZAWA Hiroyuki > > This patch looks good to me, but some nitpicks. > > > --- > > include/linux/res_counter.h | 11 +++++++++++ > > mm/memcontrol.c | 25 ++++++++++++++++++++++++- > > 2 files changed, 35 insertions(+), 1 deletion(-) > > > > Index: mmotm-0125/include/linux/res_counter.h > > =================================================================== > > --- mmotm-0125.orig/include/linux/res_counter.h > > +++ mmotm-0125/include/linux/res_counter.h > > @@ -182,6 +182,17 @@ static inline bool res_counter_check_und > > return ret; > > } > > > > +static inline s64 res_counter_check_margin(struct res_counter *cnt) > > +{ > > + s64 ret; > > + unsigned long flags; > > + > > + spin_lock_irqsave(&cnt->lock, flags); > > + ret = cnt->limit - cnt->usage; > > + spin_unlock_irqrestore(&cnt->lock, flags); > > + return ret; > > +} > > + > > static inline bool res_counter_check_under_soft_limit(struct res_counter *cnt) > > { > > bool ret; > > Index: mmotm-0125/mm/memcontrol.c > > =================================================================== > > --- mmotm-0125.orig/mm/memcontrol.c > > +++ mmotm-0125/mm/memcontrol.c > > @@ -1111,6 +1111,22 @@ static bool mem_cgroup_check_under_limit > > return false; > > } > > > > +static s64 mem_cgroup_check_margin(struct mem_cgroup *mem) > > +{ > > + s64 mem_margin; > > + > > + if (do_swap_account) { > > + s64 memsw_margin; > > + > > + mem_margin = res_counter_check_margin(&mem->res); > > + memsw_margin = res_counter_check_margin(&mem->memsw); > > + if (mem_margin > memsw_margin) > > + mem_margin = memsw_margin; > > + } else > > + mem_margin = res_counter_check_margin(&mem->res); > > + return mem_margin; > > +} > > + > How about > > mem_margin = res_counter_check_margin(&mem->res); > if (do_swap_account) > memsw_margin = res_counter_check_margin(&mem->memsw); > else > memsw_margin = RESOURCE_MAX; > > return min(mem_margin, memsw_margin); > > ? > I think using min() makes it more clear what this function does. > Ok. > > static unsigned int get_swappiness(struct mem_cgroup *memcg) > > { > > struct cgroup *cgrp = memcg->css.cgroup; > > @@ -1853,7 +1869,14 @@ static int __mem_cgroup_do_charge(struct > > * Check the limit again to see if the reclaim reduced the > > * current usage of the cgroup before giving up > > */ > > - if (ret || mem_cgroup_check_under_limit(mem_over_limit)) > > + if (mem_cgroup_check_margin(mem_over_limit) >= csize) > > + return CHARGE_RETRY; > > + > > + /* > > + * If the charge size is a PAGE_SIZE, it's not hopeless while > > + * we can reclaim a page. > > + */ > > + if (csize == PAGE_SIZE && ret) > > return CHARGE_RETRY; > > > > /* > > > checkpatch complains some whitespace warnings. > will fix soon. -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org