From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932123AbWEXOxg (ORCPT ); Wed, 24 May 2006 10:53:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932154AbWEXOxg (ORCPT ); Wed, 24 May 2006 10:53:36 -0400 Received: from mga06.intel.com ([134.134.136.21]:46216 "EHLO orsmga101.jf.intel.com") by vger.kernel.org with ESMTP id S932123AbWEXOxg (ORCPT ); Wed, 24 May 2006 10:53:36 -0400 X-IronPort-AV: i="4.05,167,1146466800"; d="scan'208"; a="40724790:sNHT97369202" Date: Wed, 24 May 2006 07:51:28 -0700 From: Ashok Raj To: KAMEZAWA Hiroyuki Cc: Ashok Raj , linux-kernel@vger.kernel.org, y-goto@jp.fujitsu.com, ktokunag@redhat.com, akpm@osdl.org Subject: Re: [RFC][PATCH] node hotplug : register_cpu() changes [0/3] Message-ID: <20060524075128.A32074@unix-os.sc.intel.com> References: <20060523195636.693e00d6.kamezawa.hiroyu@jp.fujitsu.com> <20060523075202.A24516@unix-os.sc.intel.com> <20060524091816.5a3960b9.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20060524091816.5a3960b9.kamezawa.hiroyu@jp.fujitsu.com>; from kamezawa.hiroyu@jp.fujitsu.com on Wed, May 24, 2006 at 09:18:15AM +0900 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 24, 2006 at 09:18:15AM +0900, KAMEZAWA Hiroyuki wrote: > On Tue, 23 May 2006 07:52:03 -0700 > Ashok Raj wrote: > > > On Tue, May 23, 2006 at 07:56:36PM +0900, KAMEZAWA Hiroyuki wrote: > > > I found acpi container, which describes node, could evaluate cpu before > > > memory. This means cpu-hot-add occurs before memory hot add. > > > > > > > Is it possible to process memory before cpu in container hot-add code? > > > > Maybe No. I know ACPI people doesn't want to add special handling for cpu/memory > in a container. It complicates the code very much. Iam not attached to the API change, so disassociating the node from cpu is ok. It just feels a bit weird to say node is not online. Probably ACPI doesnt give a precise way to put the dependencies (in a certain order), there are EDL/EJD, but they have limitations and not directly imply a dependency like this. But container code having to deal with this dependency for add/remove is probably ok. i hope container would eventually perform onlining the pieces from user space scripts via udev like mechanisms. I remember folks from SGI posting patches to cpu only nodes in the past. Same way there are probably IO only nodes. Are you sure we cover these cases as well. > > > > In most part, cpu-hot-add doesn't depend on node hot add. > > > But register_cpu, which creates symbolic link from node to cpu, requires > > > > Dont you need all per-cpu allocated on that node? Or is it from node0 or > > something for all hotpluggable cpus? > > -- Cheers, Ashok Raj - Open Source Technology Center