Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932676AbVIMPbL (ORCPT ); Tue, 13 Sep 2005 11:31:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932677AbVIMPbL (ORCPT ); Tue, 13 Sep 2005 11:31:11 -0400 Received: from colin.muc.de ([193.149.48.1]:47371 "EHLO mail.muc.de") by vger.kernel.org with ESMTP id S932676AbVIMPbK (ORCPT ); Tue, 13 Sep 2005 11:31:10 -0400 Date: 13 Sep 2005 17:31:06 +0200 Date: Tue, 13 Sep 2005 17:31:06 +0200 From: Andi Kleen To: Zwane Mwaikambo Cc: Ashok Raj , Andrew Morton , Linux Kernel Subject: Re: [patch 13/14] x86_64: Use common functions in cluster and physflat mode Message-ID: <20050913153106.GB14316@muc.de> References: <200509032135.j83LZ8gX020554@shell0.pdx.osdl.net> <20050905231628.GA16476@muc.de> <20050906161215.B19592@unix-os.sc.intel.com> <20050909134503.A29351@unix-os.sc.intel.com> <20050911230220.GA73228@muc.de> <20050912152308.A18649@unix-os.sc.intel.com> <20050913081054.GB37889@muc.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1219 Lines: 29 On Tue, Sep 13, 2005 at 07:53:03AM -0700, Zwane Mwaikambo wrote: > On Tue, 13 Sep 2005, Andi Kleen wrote: > > > > We should probably remove the !HOTPLUG case and just use the mask version > > > for all cases <=8 CPUS, use physflat or the cluster mode for >8cpus as > > > the case may be, instead of defaulting to sequence_IPI which seems > > > a little overkill for the intended purpose. > > > > Or just always use physflat and remove the logical flat case? > > That seems cleanest to me. Any objections? > > My objection is the number of APIC writes required to issue IPIs to a > group of processors, however i do understand that it would help local APIC accesses are cheap, they don't go over any external bus. It's not like a PCI cycle. > maintainability and testing coverage if we reduce the number of operating > modes, are you proposing physflat for _everything_ ? On everything that's currently run by flat yes. Possibly the others too when tested. -Andi - 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/