From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754195AbZEIVXR (ORCPT ); Sat, 9 May 2009 17:23:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752699AbZEIVW7 (ORCPT ); Sat, 9 May 2009 17:22:59 -0400 Received: from smtp-out.google.com ([216.239.33.17]:4857 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751005AbZEIVW6 (ORCPT ); Sat, 9 May 2009 17:22:58 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id: references:user-agent:mime-version:content-type:x-system-of-record; b=pPmRrf4e1viZEZjMVzZgzRU3M9MdFvKc+Quin0WMgqzyOBPbGxodhWCLEFTiMwsBF l7HD38v1ZoIzshh9BGfdQ== Date: Sat, 9 May 2009 14:22:48 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: "Rafael J. Wysocki" cc: Andrew Morton , fengguang.wu@intel.com, linux-pm@lists.linux-foundation.org, pavel@ucw.cz, Linus Torvalds , jens.axboe@oracle.com, alan-jenkins@tuffmail.co.uk, linux-kernel@vger.kernel.org, kernel-testers@vger.kernel.org, Mel Gorman Subject: Re: [PATCH 1/5] mm: Add __GFP_NO_OOM_KILL flag In-Reply-To: <200905090155.44635.rjw@sisk.pl> Message-ID: References: <200905072218.50782.rjw@sisk.pl> <200905090155.44635.rjw@sisk.pl> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 9 May 2009, Rafael J. Wysocki wrote: > > All of your tasks are in D state other than kthreads, right? That means > > they won't be in the oom killer (thus no zones are oom locked), so you can > > easily do this > > > > struct zone *z; > > for_each_populated_zone(z) > > zone_set_flag(z, ZONE_OOM_LOCKED); > > > > and then > > > > for_each_populated_zone(z) > > zone_clear_flag(z, ZONE_OOM_LOCKED); > > > > The serialization is done with trylocks so this will never invoke the oom > > killer because all zones in the allocator's zonelist will be oom locked. > > Well, that might have been a good idea if it actually had worked. :-( > > > Why does this not work for you? > > If I set image_size to something below "hard core working set" + > totalreserve_pages, preallocate_image_memory() hangs the > box (please refer to the last patch I sent, > http://patchwork.kernel.org/patch/22423/). > This has been changed in the latest mmotm with Mel's page alloactor patches (and I think yours should be based on mmotm). Specifically, page-allocator-break-up-the-allocator-entry-point-into-fast-and-slow-paths.patch. Before his patchset, zonelists that had ZONE_OOM_LOCKED set for at least one of their zones would unconditionally goto restart. Now, if order > PAGE_ALLOC_COSTLY_ORDER, it gives up and returns NULL. Otherwise, it does goto restart. So if your allocation has order > PAGE_ALLOC_COSTLY_ORDER, using the ZONE_OOM_LOCKED approach to locking out the oom killer will work just fine in mmotm. From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Rientjes Subject: Re: [PATCH 1/5] mm: Add __GFP_NO_OOM_KILL flag Date: Sat, 9 May 2009 14:22:48 -0700 (PDT) Message-ID: References: <200905072218.50782.rjw@sisk.pl> <200905090155.44635.rjw@sisk.pl> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=google.com; s=beta; t=1241904175; bh=sIpjOQLqMJxuwI3RYk11FfJ0HJM=; h=DomainKey-Signature:Date:From:X-X-Sender:To:cc:Subject: In-Reply-To:Message-ID:References:User-Agent:MIME-Version: Content-Type:X-System-Of-Record; b=lQYOpgxh20B/S8knvcDu0p9URx49LfW zKYDx7tZZ9BM6TttUnbrINkI3p4BCmV5/dAj7cB5ytqUvgNssJDA+pQ== In-Reply-To: <200905090155.44635.rjw-KKrjLPT3xs0@public.gmane.org> Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: TEXT/PLAIN; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Rafael J. Wysocki" Cc: Andrew Morton , fengguang.wu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, linux-pm-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, pavel-+ZI9xUNit7I@public.gmane.org, Linus Torvalds , jens.axboe-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, alan-jenkins-cCz0Lq7MMjm9FHfhHBbuYA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kernel-testers-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Mel Gorman On Sat, 9 May 2009, Rafael J. Wysocki wrote: > > All of your tasks are in D state other than kthreads, right? That means > > they won't be in the oom killer (thus no zones are oom locked), so you can > > easily do this > > > > struct zone *z; > > for_each_populated_zone(z) > > zone_set_flag(z, ZONE_OOM_LOCKED); > > > > and then > > > > for_each_populated_zone(z) > > zone_clear_flag(z, ZONE_OOM_LOCKED); > > > > The serialization is done with trylocks so this will never invoke the oom > > killer because all zones in the allocator's zonelist will be oom locked. > > Well, that might have been a good idea if it actually had worked. :-( > > > Why does this not work for you? > > If I set image_size to something below "hard core working set" + > totalreserve_pages, preallocate_image_memory() hangs the > box (please refer to the last patch I sent, > http://patchwork.kernel.org/patch/22423/). > This has been changed in the latest mmotm with Mel's page alloactor patches (and I think yours should be based on mmotm). Specifically, page-allocator-break-up-the-allocator-entry-point-into-fast-and-slow-paths.patch. Before his patchset, zonelists that had ZONE_OOM_LOCKED set for at least one of their zones would unconditionally goto restart. Now, if order > PAGE_ALLOC_COSTLY_ORDER, it gives up and returns NULL. Otherwise, it does goto restart. So if your allocation has order > PAGE_ALLOC_COSTLY_ORDER, using the ZONE_OOM_LOCKED approach to locking out the oom killer will work just fine in mmotm.