From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754690Ab0IIPZc (ORCPT ); Thu, 9 Sep 2010 11:25:32 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:24938 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752863Ab0IIPZb (ORCPT ); Thu, 9 Sep 2010 11:25:31 -0400 Date: Thu, 9 Sep 2010 08:23:31 -0700 From: Randy Dunlap To: sedat.dilek@gmail.com Cc: Sedat Dilek , LKML , linux-mm@kvack.org Subject: Re: mm/Kconfig: warning: (COMPACTION && EXPERIMENTAL && HUGETLB_PAGE && MMU) selects MIGRATION which has unmet direct dependencies (NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE) Message-Id: <20100909082331.7278e76b.randy.dunlap@oracle.com> In-Reply-To: References: Organization: Oracle Linux Eng. X-Mailer: Sylpheed 2.7.1 (GTK+ 2.16.6; x86_64-unknown-linux-gnu) 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 On Thu, 9 Sep 2010 17:10:34 +0200 Sedat Dilek wrote: > Hi, > > while build latest 2.6.36-rc3 I get this warning: > > [ build.log] > ... > warning: (COMPACTION && EXPERIMENTAL && HUGETLB_PAGE && MMU) selects > MIGRATION which has unmet direct dependencies (NUMA || > ARCH_ENABLE_MEMORY_HOTREMOVE) > ... > > Here the excerpt of... > > [ mm/Kconfig ] > ... > # support for memory compaction > config COMPACTION > bool "Allow for memory compaction" > select MIGRATION > depends on EXPERIMENTAL && HUGETLB_PAGE && MMU > help > Allows the compaction of memory for the allocation of huge pages. > ... > > I have set the following kernel-config parameters: > > $ egrep 'COMPACTION|HUGETLB_PAGE|MMU|MIGRATION|NUMA|ARCH_ENABLE_MEMORY_HOTREMOVE' > linux-2.6.36-rc3/debian/build/build_i386_none_686/.config > CONFIG_MMU=y > # CONFIG_IOMMU_HELPER is not set > CONFIG_IOMMU_API=y > CONFIG_COMPACTION=y > CONFIG_MIGRATION=y > CONFIG_MMU_NOTIFIER=y > CONFIG_HUGETLB_PAGE=y > # CONFIG_IOMMU_STRESS is not set > > Looks like I have no NUMA or ARCH_ENABLE_MEMORY_HOTREMOVE set. > > Ok, it is a *warning*... Andrea Arcangeli posted a patch for this on linux-mm on 2010-SEP-03. (below) --- From: Andrea Arcangeli COMPACTION enables MIGRATION, but MIGRATION spawns a warning if numa or memhotplug aren't selected. However MIGRATION doesn't depend on them. I guess it's just trying to be strict doing a double check on who's enabling it, but it doesn't know that compaction also enables MIGRATION. Signed-off-by: Andrea Arcangeli --- diff --git a/mm/Kconfig b/mm/Kconfig --- a/mm/Kconfig +++ b/mm/Kconfig @@ -189,7 +189,7 @@ config COMPACTION 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 in