From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754170AbYI0UC3 (ORCPT ); Sat, 27 Sep 2008 16:02:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753269AbYI0UCV (ORCPT ); Sat, 27 Sep 2008 16:02:21 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:48054 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753224AbYI0UCV (ORCPT ); Sat, 27 Sep 2008 16:02:21 -0400 Date: Sat, 27 Sep 2008 22:02:14 +0200 From: Ingo Molnar To: Jack Steiner Cc: tglx@linutronix.de, linux-kernel@vger.kernel.org, "H. Peter Anvin" , Yinghai Lu Subject: Re: [PATCH] - UV fix for size of hub mappings Message-ID: <20080927200214.GB28937@elte.hu> References: <20080925125210.GA22404@sgi.com> <20080927174233.GB26047@elte.hu> <20080927195615.GA244243@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080927195615.GA244243@sgi.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Jack Steiner wrote: > > x2apic support is available in tip/master, so it would be nice to > > glue UV to generic x2apic support properly and remove duplication > > and fixmes. > > Good point. I'll send the fixes to you early next week. Recently, I've > been focused on a distro release which is still waiting for the x2apic > code. However, I don't need to wait to fix this upstream... great! > > For example, do we really need apic_x2apic_uv_x, or could we use > > apic_x2apic_cluster? > > Unfortunately, we really need a uv genapic. IPIs on large UV systems > can't use an x2apic model. Because of the size of our large systems, > APICIDs in the cpu MSRs are not globally unique. We have a special > feature in the UV chipset that must be used for on large systems for > IPIs. Small & medium sized system can and do use the x2apic genapic. not a problem really - it's not really complex or intrusive, we just want to make sure all unnecessary duplication is eliminated. Ingo