From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751017AbVIGGt4 (ORCPT ); Wed, 7 Sep 2005 02:49:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751021AbVIGGt4 (ORCPT ); Wed, 7 Sep 2005 02:49:56 -0400 Received: from colin.muc.de ([193.149.48.1]:12043 "EHLO mail.muc.de") by vger.kernel.org with ESMTP id S1751016AbVIGGtz (ORCPT ); Wed, 7 Sep 2005 02:49:55 -0400 Date: 7 Sep 2005 08:49:50 +0200 Date: Wed, 7 Sep 2005 08:49:50 +0200 From: Andi Kleen To: Ashok Raj Cc: akpm@osdl.org, linux-kernel@vger.kernel.org Subject: Re: [patch 09/14] x86_64: Don't call enforce_max_cpus when hotplug is enabled Message-ID: <20050907064950.GB96684@muc.de> References: <200509032135.j83LZ5Od020541@shell0.pdx.osdl.net> <20050905044821.GH17516@muc.de> <20050906155617.A19439@unix-os.sc.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050906155617.A19439@unix-os.sc.intel.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 06, 2005 at 03:56:17PM -0700, Ashok Raj wrote: > Hi Andi > > On Mon, Sep 05, 2005 at 06:48:21AM +0200, Andi Kleen wrote: > > On Sat, Sep 03, 2005 at 02:33:26PM -0700, akpm@osdl.org wrote: > > > > > > From: Ashok Raj > > > > > > No need to enforce_max_cpus when hotplug code is enabled. This nukes out > > > cpu_present_map and cpu_possible_map making it impossible to add new cpus in > > > the system. > > > > I see the point, but the implementation is wrong. If anything > > we shouldn't do it neither for the !HOTPLUG_CPU case.Why did > > you not do it unconditionally? > > > > I would prefer to keep the special cases for hotplug to be > > as narrow as possible. > > Link to earlier discussion below > > http://marc.theaimsgroup.com/?l=linux-kernel&m=112317327529855&w=2 > > I had suggested that we remove it completely in our discussion but i didnt > hear anything from you after that, so i thought that was acceptable. Just because I don't follow up on everything doesn't necessarily mean the patch is acceptable. > > You had suggested in that discussion that it would be better to add an > option for startup. Iam opposed to adding any option, when we certainly know I suggested to auto detect it based on ACPI information. I don't think I ever wrote anything about an option. If that is not possible it's better to always use the sequence mechanism. > there are no users. Earlier based on your suggestion i added a startup > option to choose ipi broadcast mode, which you promptly removed when you > put physflat changes. I think its better to not add any option without > real need. Do you agree? Yes. > Please reply if you want me to remove the !HOTPLUG case which is my > preference as well, and maybe while the memory is fresh, we can stick > with it this time when we are in the same page :-( Yes, as I wrote earlier hotplug should be removed. -Andi P.S.: Don't bother sending me such "blame game" mails again. I will just d them next time because they're a waste of time.