Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761444AbZJIUXp (ORCPT ); Fri, 9 Oct 2009 16:23:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761404AbZJIUXo (ORCPT ); Fri, 9 Oct 2009 16:23:44 -0400 Received: from e8.ny.us.ibm.com ([32.97.182.138]:50375 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761421AbZJIUXn (ORCPT ); Fri, 9 Oct 2009 16:23:43 -0400 Date: Fri, 9 Oct 2009 15:23:04 -0500 From: Robert Jennings To: Andrew Morton Cc: Mel Gorman , Ingo Molnar , Badari Pulavarty , Brian King , Benjamin Herrenschmidt , Paul Mackerras , Martin Schwidefsky , Gerald Schaefer , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@ozlabs.org, KAMEZAWA Hiroyuki Subject: Re: [PATCH 1/2][v2] mm: add notifier in pageblock isolation for balloon drivers Message-ID: <20091009202304.GB19114@austin.ibm.com> Mail-Followup-To: Andrew Morton , Mel Gorman , Ingo Molnar , Badari Pulavarty , Brian King , Benjamin Herrenschmidt , Paul Mackerras , Martin Schwidefsky , Gerald Schaefer , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@ozlabs.org, KAMEZAWA Hiroyuki References: <20091002184458.GC4908@austin.ibm.com> <20091008163449.00dce972.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091008163449.00dce972.akpm@linux-foundation.org> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2066 Lines: 47 * Andrew Morton (akpm@linux-foundation.org) wrote: > On Fri, 2 Oct 2009 13:44:58 -0500 > Robert Jennings wrote: > > > Memory balloon drivers can allocate a large amount of memory which > > is not movable but could be freed to accomodate memory hotplug remove. > > > > Prior to calling the memory hotplug notifier chain the memory in the > > pageblock is isolated. If the migrate type is not MIGRATE_MOVABLE the > > isolation will not proceed, causing the memory removal for that page > > range to fail. > > > > Rather than failing pageblock isolation if the the migrateteype is not > > MIGRATE_MOVABLE, this patch checks if all of the pages in the pageblock > > are owned by a registered balloon driver (or other entity) using a > > notifier chain. If all of the non-movable pages are owned by a balloon, > > they can be freed later through the memory notifier chain and the range > > can still be isolated in set_migratetype_isolate(). > > The patch looks sane enough to me. > > I expect that if the powerpc and s390 guys want to work on CMM over the > next couple of months, they'd like this patch merged into 2.6.32. It's > a bit larger and more involved than one would like, but I guess we can > do that if suitable people (Mel? Kamezawa?) have had a close look and > are OK with it. > > What do people think? I'd love to get it in 2.6.32 if that's possible. I have gone over the comments from Mel and Kamezawa I produced a new patchset. I just finished testing it (and I also tested with CONFIG_MEMORY_HOTPLUG_SPARSE=n) and it will be posted shortly. > > Has it been carefully compile- and run-time tested with > CONFIG_MEMORY_HOTPLUG_SPARSE=n? Yes, I have compiled the kernel CONFIG_MEMORY_HOTPLUG_SPARSE=n and made sure that we didn't have any problems. --Robert Jennings -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/