From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 22 Dec 2002 20:16:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 22 Dec 2002 20:16:15 -0500 Received: from petasus.ch.intel.com ([143.182.124.5]:15072 "EHLO petasus.ch.intel.com") by vger.kernel.org with ESMTP id convert rfc822-to-8bit; Sun, 22 Dec 2002 20:16:14 -0500 content-class: urn:content-classes:message Subject: RE: [PATCH][2.4] generic support for systems with more than 8 CPUs (1/2) Date: Sun, 22 Dec 2002 17:24:15 -0800 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-MS-Has-Attach: Content-Transfer-Encoding: 7BIT X-MS-TNEF-Correlator: Thread-Topic: [PATCH][2.4] generic support for systems with more than 8 CPUs (1/2) Thread-Index: AcKp4GkE0rrhnhXPEde/HABQi2jWFgAP4QqQ X-MimeOLE: Produced By Microsoft Exchange V6.0.6334.0 From: "Pallipadi, Venkatesh" To: "Martin J. Bligh" , "Nakajima, Jun" , "Van Maren, Kevin" , "William Lee Irwin III" , "Christoph Hellwig" , "James Cleverdon" , "John Stultz" , "Mallick, Asit K" , "Saxena, Sunil" , "Linux Kernel" Cc: "Protasevich, Natalie" X-OriginalArrivalTime: 23 Dec 2002 01:24:15.0545 (UTC) FILETIME=[01CA7290:01C2AA22] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > From: Martin J. Bligh [mailto:mbligh@aracnet.com] > > 1/2 : checking for xAPIC support in the system > > OK, that looks pretty sane - one question: > > > - if ((clustered_apic_mode != CLUSTERED_APIC_XAPIC) && > > + if (!xapic_support && > > + (clustered_apic_mode != CLUSTERED_APIC_XAPIC) && > > When does xapic_support differ from > (clustered_apic_mode == CLUSTERED_APIC_XAPIC) ? > They are quite different. Infact CLUSTERED_APIC_XAPIC just means using physical APIC mode and is kind of a misnomer as xAPIC doesn't necessariy mean physical APIC mode. xapic_support says whether xAPIC support is there or not. Then APICs can be configured either in physical or logical modes. I mainly need this as with xAPIC support, we have: - LAPIC and IOAPIC have there own name space, - max or 255 CPUS with 0xff as broadcast, as opposed to 0xf broadcast in case of no xAPIC > Do you want to use a physical flat xapic mode for your stuff, or the > same clustered physical mode as the Summit stuff? If the latter, then > the new switch seems unnecessary .... Now I am getting a bit confused here. I am using physical mode with no clustering whatsoever. Thats what I felt even Summit was doing in 2.4. Thanks, -Venkatesh