From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 15 Jan 2003 15:08:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 15 Jan 2003 15:08:40 -0500 Received: from holomorphy.com ([66.224.33.161]:48780 "EHLO holomorphy") by vger.kernel.org with ESMTP id ; Wed, 15 Jan 2003 15:08:38 -0500 Date: Wed, 15 Jan 2003 12:17:19 -0800 From: William Lee Irwin III To: "Protasevich, Natalie" Cc: "Pallipadi, Venkatesh" , "Martin J. Bligh" , "Nakajima, Jun" , Christoph Hellwig , James Cleverdon , Linux Kernel Subject: Re: [PATCH] (0/7) Finish moving NUMA-Q into subarch, cleanup Message-ID: <20030115201719.GM919@holomorphy.com> Mail-Followup-To: William Lee Irwin III , "Protasevich, Natalie" , "Pallipadi, Venkatesh" , "Martin J. Bligh" , "Nakajima, Jun" , Christoph Hellwig , James Cleverdon , Linux Kernel References: <3FAD1088D4556046AEC48D80B47B478C022BD907@usslc-exch-4.slc.unisys.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3FAD1088D4556046AEC48D80B47B478C022BD907@usslc-exch-4.slc.unisys.com> User-Agent: Mutt/1.3.25i Organization: The Domain of Holomorphy Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 15, 2003 at 01:30:37PM -0600, Protasevich, Natalie wrote: > ... and one more from me: isn't it time to let IO-APIC id be 8 bit in the > asm/io_apic.h (make it a union fot both?..)? > Look what I have to do in io_apic.h to get around it and ... "mister, have a > heart": Point taken; it doesn't burn NUMA-Q, but this probably hits Summit (with its much more recent APIC and IO-APIC revisions). I don't see why not. The hardware is there, time to drop in the code to handle it. At some point in the past, I wrote: >> There are also somewhat deeper issues with vector assignments to >> interrupt sources that prevent elevating any of the above to useful >> levels and utilizing them. The assumptions based on the vector assignment >> algorithm appear to be widely distributed enough to discourage me after >> an initial attempt or two to get any kind of useful interrupt routing >> for a number of IRQ sources larger than the number of vectors. On Wed, Jan 15, 2003 at 01:30:37PM -0600, Protasevich, Natalie wrote: > I strongly suggest to take a look in IA64 implementation. > They have 1:1 correspondence between IRQ and vector and don't seem to be > able to run out of vectors or IRQs. Given that almost nothing actually cares what the irq numbers are, it sounds like a really good idea to encode the node ID in the upper bits and the vector in the lower bits (SN2 uses cpuid). I'll try it out. Thanks! Bill