From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758267Ab0CaX4J (ORCPT ); Wed, 31 Mar 2010 19:56:09 -0400 Received: from hera.kernel.org ([140.211.167.34]:39273 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757328Ab0CaX4E (ORCPT ); Wed, 31 Mar 2010 19:56:04 -0400 Message-ID: <4BB3E0CA.5060405@kernel.org> Date: Wed, 31 Mar 2010 16:54:50 -0700 From: Yinghai Lu User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.8) Gecko/20100228 SUSE/3.0.3-1.1.1 Thunderbird/3.0.3 MIME-Version: 1.0 To: "H. Peter Anvin" CC: Ingo Molnar , James Morris , linux-kernel@vger.kernel.org, airlied@linux.ie Subject: Re: Config NO_BOOTMEM breaks my amd64 box References: <4BB2EB1B.8090303@zytor.com> <4BB3C739.2020106@kernel.org> <20100331221341.GA20441@elte.hu> <4BB3C9B0.4000205@kernel.org> <20100331224108.GA11284@elte.hu> <4BB3D0F4.902@kernel.org> <4BB3DC23.50005@zytor.com> In-Reply-To: <4BB3DC23.50005@zytor.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/31/2010 04:34 PM, H. Peter Anvin wrote: > On 03/31/2010 03:47 PM, Yinghai Lu wrote: >>> >>> Well and that whole #ifdeffery is disgusting as well - even if the goal was to >>> remove CONFIG_NO_BOOTMEM ASAP. >>> >>> Please learn to use proper intermediate helper functions and at minimum put >>> the conversion ugliness somewhere that doesnt intrude our daily flow in .c >>> files. The best rule is to _never ever_ put an #ifdef construct into a .c >>> file. It doesnt matter what the goal if the #ifdef is - such ugliness in code >>> is never justified. >> >> if you agree that i can have one nobootmem.c in mm/ >> > > That would be better, or more commonly, use inlines. > > I'm still totally puzzled about this patch as well as the comment: > > +#if defined(CONFIG_NO_BOOTMEM) && defined(MAX_NUMNODES) > + /* In case some 32bit systems don't have RAM installed on node0 */ > + totalram_pages += free_all_memory_core_early(MAX_NUMNODES); > +#else > totalram_pages += free_all_bootmem(); > +#endif > > > Why is that "32 bits" specific? Second, MAX_NUMNODES is defined > whenever is included, so what on Earth is this supposed > to signify? Are you trying to say MAX_NUMNODES > 1? Or are you trying > to say CONFIG_NUMA? you are right, this one should be more clear. Subject: [PATCH -v2] nobootmem, x86: Fix 32bit system without RAM on Node0 when 32bit numa is used, free_all_bootmem() will still only go over with node id 0. If node 0 doesn't have RAM installed, We need to go with node1 because early_node_map still use 1 for all ranges, and ram from node1 becom low ram. Try to use MAX_NUMNODES like 64 numa does. Signed-off-by: Yinghai Lu --- mm/bootmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux-2.6/mm/bootmem.c =================================================================== --- linux-2.6.orig/mm/bootmem.c +++ linux-2.6/mm/bootmem.c @@ -303,7 +303,7 @@ unsigned long __init free_all_bootmem_no unsigned long __init free_all_bootmem(void) { #ifdef CONFIG_NO_BOOTMEM - return free_all_memory_core_early(NODE_DATA(0)->node_id); + return free_all_memory_core_early(MAX_NUMNODES); #else return free_all_bootmem_core(NODE_DATA(0)->bdata); #endif > > Furthermore, I really don't see the connection between this and James > Morris' reported problem, which he reports as "amd64", which presumably > is an x86-64 kernel and not 32 bits... James, is that correct? Any > more details you can give about the system? I *really* don't want to go > into cargo cult programming mode, that would suck eggs no matter what. it happened one of my test setup, node0 ram disappear somehow. and i found the 32bit numa doesn't work on that. Thanks Yinghai