Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753996Ab0BSAYu (ORCPT ); Thu, 18 Feb 2010 19:24:50 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:50265 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753409Ab0BSAYn (ORCPT ); Thu, 18 Feb 2010 19:24:43 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Fri, 19 Feb 2010 09:21:11 +0900 From: KAMEZAWA Hiroyuki To: Mel Gorman Cc: Andrea Arcangeli , Christoph Lameter , Adam Litke , Avi Kivity , David Rientjes , KOSAKI Motohiro , Rik van Riel , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 05/12] Allow CONFIG_MIGRATION to be set without CONFIG_NUMA or memory hot-remove Message-Id: <20100219092111.ee280622.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <1266516162-14154-6-git-send-email-mel@csn.ul.ie> References: <1266516162-14154-1-git-send-email-mel@csn.ul.ie> <1266516162-14154-6-git-send-email-mel@csn.ul.ie> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 2.7.1 (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 Content-Length: 2727 Lines: 83 On Thu, 18 Feb 2010 18:02:35 +0000 Mel Gorman wrote: > CONFIG_MIGRATION currently depends on CONFIG_NUMA or on the architecture > being able to hot-remove memory. The main users of page migration such as > sys_move_pages(), sys_migrate_pages() and cpuset process migration are > only beneficial on NUMA so it makes sense. > > As memory compaction will operate within a zone and is useful on both NUMA > and non-NUMA systems, this patch allows CONFIG_MIGRATION to be set if the > user selects CONFIG_COMPACTION as an option. > > Signed-off-by: Mel Gorman > Reviewed-by: Christoph Lameter > Reviewed-by: Rik van Riel Reviewed-by: KAMEZAWA Hiroyuki But see below. > --- > mm/Kconfig | 20 ++++++++++++++++---- > 1 files changed, 16 insertions(+), 4 deletions(-) > > diff --git a/mm/Kconfig b/mm/Kconfig > index 17b8947..b1c2781 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -168,17 +168,29 @@ config SPLIT_PTLOCK_CPUS > default "4" > > # > +# support for memory compaction > +config COMPACTION > + bool "Allow for memory compaction" > + def_bool y > + select MIGRATION > + depends on EXPERIMENTAL && HUGETLBFS > + help > + Allows the compaction of memory for the allocation of huge pages. > + I think + depends on MMU Thanks, -Kame > +# > # support for page migration > # > config MIGRATION > bool "Page migration" > def_bool y > - depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE > + depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE || COMPACTION > help > Allows the migration of the physical location of pages of processes > - while the virtual addresses are not changed. This is useful for > - example on NUMA systems to put pages nearer to the processors accessing > - the page. > + while the virtual addresses are not changed. This is useful in > + two situations. The first is on NUMA systems to put pages nearer > + to the processors accessing. The second is when allocating huge > + pages as migration can relocate pages to satisfy a huge page > + allocation instead of reclaiming. > > config PHYS_ADDR_T_64BIT > def_bool 64BIT || ARCH_PHYS_ADDR_T_64BIT > -- > 1.6.5 > > -- > 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 > -- 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/