From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id 99D6B6B003D for ; Wed, 2 Dec 2009 20:55:29 -0500 (EST) Received: from m2.gw.fujitsu.co.jp ([10.0.50.72]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id nB31tR7f030216 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Thu, 3 Dec 2009 10:55:27 +0900 Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 0439145DE57 for ; Thu, 3 Dec 2009 10:55:27 +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 CB2BD45DE4E for ; Thu, 3 Dec 2009 10:55:26 +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 B0E4F1DB803C for ; Thu, 3 Dec 2009 10:55:26 +0900 (JST) Received: from m108.s.css.fujitsu.com (m108.s.css.fujitsu.com [10.249.87.108]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 5089D1DB8038 for ; Thu, 3 Dec 2009 10:55:26 +0900 (JST) Date: Thu, 3 Dec 2009 10:52:29 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH 22/24] HWPOISON: add memory cgroup filter Message-Id: <20091203105229.afb0efc4.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20091202125842.GA13277@localhost> References: <20091202031231.735876003@intel.com> <20091202043046.519053333@intel.com> <20091202124446.GA18989@one.firstfloor.org> <20091202125842.GA13277@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Andi Kleen , Andrew Morton , KOSAKI Motohiro , Hugh Dickins , Daisuke Nishimura , Balbir Singh , Li Zefan , Paul Menage , Nick Piggin , "linux-mm@kvack.org" , LKML List-ID: On Wed, 2 Dec 2009 20:58:42 +0800 Wu Fengguang wrote: > On Wed, Dec 02, 2009 at 08:44:46PM +0800, Andi Kleen wrote: > > > > > > +static int hwpoison_filter_task(struct page *p) > > > +{ > > > > Can we make that ifdef instead of depends on ? > > Sure. Here is the updated patch. > > --- > HWPOISON: add memory cgroup filter > > The hwpoison test suite need to inject hwpoison to a collection of > selected task pages, and must not touch pages not owned by them and > thus kill important system processes such as init. (But it's OK to > mis-hwpoison free/unowned pages as well as shared clean pages. > Mis-hwpoison of shared dirty pages will kill all tasks, so the test > suite will target all or non of such tasks in the first place.) > > The memory cgroup serves this purpose well. We can put the target > processes under the control of a memory cgroup, and tell the hwpoison > injection code to only kill pages associated with some active memory > cgroup. > > The prerequisite for doing hwpoison stress tests with mem_cgroup is, > the mem_cgroup code tracks task pages _accurately_ (unless page is > locked). Which we believe is/should be true. > > The benifits are simplification of hwpoison injector code. Also the > mem_cgroup code will automatically be tested by hwpoison test cases. > > The alternative interfaces pin-pfn/unpin-pfn can also delegate the > (process and page flags) filtering functions reliably to user space. > However prototype implementation shows that this scheme adds more > complexity than we wanted. > > CC: KOSAKI Motohiro > CC: Hugh Dickins > CC: Daisuke Nishimura > CC: Balbir Singh > CC: KAMEZAWA Hiroyuki > CC: Li Zefan > CC: Paul Menage > CC: Nick Piggin > CC: Andi Kleen > Signed-off-by: Wu Fengguang > --- > mm/Kconfig | 2 +- > mm/hwpoison-inject.c | 7 +++++++ > mm/internal.h | 1 + > mm/memory-failure.c | 28 ++++++++++++++++++++++++++++ > 4 files changed, 37 insertions(+), 1 deletion(-) > > --- linux-mm.orig/mm/memory-failure.c 2009-12-01 09:56:06.000000000 +0800 > +++ linux-mm/mm/memory-failure.c 2009-12-02 20:56:55.000000000 +0800 > @@ -96,6 +96,31 @@ static int hwpoison_filter_flags(struct > return -EINVAL; > } > > +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP > +u32 hwpoison_filter_memcg; > +static int hwpoison_filter_task(struct page *p) > +{ > + struct mem_cgroup *mem; > + struct cgroup_subsys_state *css; > + > + if (!hwpoison_filter_memcg) > + return 0; > + > + mem = try_get_mem_cgroup_from_page(p); > + if (!mem) > + return -EINVAL; > + > + css = mem_cgroup_css(mem); > + if (!css) > + return -EINVAL; > + > + css_put(css); > + return 0; > +} Hmm..can you adds comment ? What does this function is for ? Is this more meaningful than PageLRU(page) etc..? Thanks, -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/ . Don't email: email@kvack.org