From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751055Ab0AVFhU (ORCPT ); Fri, 22 Jan 2010 00:37:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750923Ab0AVFhT (ORCPT ); Fri, 22 Jan 2010 00:37:19 -0500 Received: from mga14.intel.com ([143.182.124.37]:47092 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750857Ab0AVFhR (ORCPT ); Fri, 22 Jan 2010 00:37:17 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.47,316,1257148800"; d="scan'208";a="235595968" Date: Fri, 22 Jan 2010 13:37:11 +0800 From: Wu Fengguang To: Xiaotian Feng Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Andrew Morton , Chen Liqin , Lennox Wu , Ralf Baechle , =?utf-8?Q?Am=C3=A9rico?= Wang , "linux-mips@linux-mips.org" , KAMEZAWA Hiroyuki , Yinghai Lu , "x86@kernel.org" , LKML , Andi Kleen , "Zheng, Shaohui" Subject: Re: [PATCH 1/3] resources: introduce generic page_is_ram() Message-ID: <20100122053711.GB3761@localhost> References: <20100122032102.137106635@intel.com> <20100122033004.193166010@intel.com> <7b6bb4a51001212115j741e91c4p61f3f1d6e2ec1de4@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <7b6bb4a51001212115j741e91c4p61f3f1d6e2ec1de4@mail.gmail.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 21, 2010 at 10:15:50PM -0700, Xiaotian Feng wrote: > On Fri, Jan 22, 2010 at 11:21 AM, Wu Fengguang wrote: > > It's based on walk_system_ram_range(), for archs that don't have > > their own page_is_ram(). > > > > The static verions in MIPS and SCORE are also made global. > > > > CC: Chen Liqin > > CC: Lennox Wu > > CC: Ralf Baechle > > CC: Américo Wang > > CC: linux-mips@linux-mips.org > > CC: KAMEZAWA Hiroyuki > > CC: Yinghai Lu > > Signed-off-by: Wu Fengguang > > --- > >  arch/mips/mm/init.c    |    2 +- > >  arch/score/mm/init.c   |    2 +- > >  include/linux/ioport.h |    2 ++ > >  kernel/resource.c      |   11 +++++++++++ > >  4 files changed, 15 insertions(+), 2 deletions(-) > > > > --- linux-mm.orig/kernel/resource.c     2010-01-22 11:20:34.000000000 +0800 > > +++ linux-mm/kernel/resource.c  2010-01-22 11:20:35.000000000 +0800 > > @@ -327,6 +327,17 @@ int walk_system_ram_range(unsigned long > > > >  #endif > > > > +#define PAGE_IS_RAM    24 > > +static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg) > > +{ > > +       return PAGE_IS_RAM; > > +} > > +int __attribute__((weak)) page_is_ram(unsigned long pfn) > > +{ > > +       return PAGE_IS_RAM == walk_system_ram_range(pfn, 1, NULL, __is_ram); > > +} > > +#undef PAGE_IS_RAM > > + > > I'm not sure, but any build test for powerpc/mips/score? Sorry, no build tests yet: /bin/sh: score-linux-gcc: command not found I just make the mips/score page_is_ram() non-static and assume that will make it compile. > walk_system_ram_range is defined when CONFIG_ARCH_HAS_WALK_MEMORY is not set. > Is it safe when CONFIG_ARCH_HAS_WALK_MEMORY is set for some powerpc archs? Good question. Grep shows that CONFIG_ARCH_HAS_WALK_MEMORY is only defined for powerpc, and it has its own page_is_ram() as well as walk_system_ram_range(). walk_system_ram_range() must be defined somewhere because it is expected to be generic routine: exported and called from both in-kernel and out-of-tree code. Thanks, Fengguang