From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id CDCF06B01B6 for ; Tue, 15 Jun 2010 20:30:56 -0400 (EDT) Message-ID: <4C181AFD.5060503@redhat.com> Date: Tue, 15 Jun 2010 20:29:49 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH 12/12] vmscan: Do not writeback pages in direct reclaim References: <1276514273-27693-1-git-send-email-mel@csn.ul.ie> <1276514273-27693-13-git-send-email-mel@csn.ul.ie> <4C16A567.4080000@redhat.com> <20100615114510.GE26788@csn.ul.ie> <4C17815A.8080402@redhat.com> <20100615135928.GK26788@csn.ul.ie> <4C178868.2010002@redhat.com> <20100615141601.GL26788@csn.ul.ie> <20100616091755.7121c7d3.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100616091755.7121c7d3.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: Mel Gorman , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Dave Chinner , Chris Mason , Nick Piggin , Johannes Weiner , Christoph Hellwig , Andrew Morton List-ID: On 06/15/2010 08:17 PM, KAMEZAWA Hiroyuki wrote: > On Tue, 15 Jun 2010 15:16:01 +0100 > Mel Gorman wrote: >> But in turn, where is mem_cgroup_hierarchical_reclaim called from direct >> reclaim? It appears to be only called from the fault path or as a result >> of the memcg changing size. >> > yes. It's only called from > - page fault > - add_to_page_cache() > > I think we'll see no stack problem. Now, memcg doesn't wakeup kswapd for > reclaiming memory, it needs direct writeback. Of course, a memcg page fault could still be triggered from copy_to_user or copy_from_user, with a fairly arbitrary stack frame above... -- All rights reversed -- 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