Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030614AbXBGKIa (ORCPT ); Wed, 7 Feb 2007 05:08:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030618AbXBGKIa (ORCPT ); Wed, 7 Feb 2007 05:08:30 -0500 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:39864 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030614AbXBGKI3 (ORCPT ); Wed, 7 Feb 2007 05:08:29 -0500 Date: Wed, 7 Feb 2007 19:07:38 +0900 From: KAMEZAWA Hiroyuki To: Andi Kleen Cc: linux-kernel@vger.kernel.org, y-goto@jp.fujitsu.com, clameter@engr.sgi.com, akpm@osdl.org Subject: Re: [2.6.20][PATCH] fix mempolicy error check on a system with memory-less-node Message-Id: <20070207190738.30f1d419.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: References: <20070206202312.4f979bcf.kamezawa.hiroyu@jp.fujitsu.com> Organization: Fujitsu X-Mailer: Sylpheed version 2.2.0 (GTK+ 2.6.10; 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 X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1261 Lines: 32 On 07 Feb 2007 11:20:06 +0100 Andi Kleen wrote: > KAMEZAWA Hiroyuki writes: > > > current mempolicy just checks whether a node is online or not. > > If there is memory-less-node, mempolicy's target node can be > > invalid. > > This patch adds a check whether a node has memory or not. > > IMHO there shouldn't be any memory less nodes. The architecture code > should not create them. The CPU should be assigned to a nearby node instead. > At least x86-64 ensures that. > AFAIK, ia64 creates nodes just depends on SRAT's possible resource information. Then, ia64 can create cpu-memory-less-node(node with no available resource.). (*)I don't like this. If we don't allow memory-less-node, we may have to add several codes for cpu-hot-add. cpus should be moved to nearby node at hotadd . And node-hot-add have to care that cpus mustn't be added before memory, cpu-driven node-hot-add will never occur. (ACPI's 'container' device spec can't guaranntee this.) -Kame - 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/