Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755713AbYCaSmU (ORCPT ); Mon, 31 Mar 2008 14:42:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754115AbYCaSmL (ORCPT ); Mon, 31 Mar 2008 14:42:11 -0400 Received: from wr-out-0506.google.com ([64.233.184.233]:48394 "EHLO wr-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753708AbYCaSmK (ORCPT ); Mon, 31 Mar 2008 14:42:10 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Q5iHzYI5wBkHqYVajb2Y7FMIkGMtptNZLTWflrXx7kLJldaEkcGTSl97ZFKIW/2RhlvPWKgUhlDBPdvpCkVjIWXDjRQtvSIElFugZ/GKPvKot3ZXMnSkMMAMgCPOPScCdbdJjcxFxsKFae1PgkROvT1sL3iNUfW8gBRYsFY1QB8= Message-ID: <86802c440803311142u4cbbdca9m830e86d46ad020af@mail.gmail.com> Date: Mon, 31 Mar 2008 11:42:09 -0700 From: "Yinghai Lu" To: "Ingo Molnar" Subject: Re: [RFC 8/8] x86_64: Support for new UV apic Cc: "Jack Steiner" , "Andi Kleen" , tglx@linutronix.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org In-Reply-To: <20080331123338.GA14636@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080324182122.GA28327@sgi.com> <20080325175657.GA6262@sgi.com> <20080326073823.GD3442@elte.hu> <86802c440803301323q5c4bd4f4k1f9bdc1d6b1a0a7b@mail.gmail.com> <20080330210356.GA13383@sgi.com> <20080330211848.GA29105@one.firstfloor.org> <86802c440803301629g6d1b896o27e12ef3c84ded2c@mail.gmail.com> <20080331021821.GC20619@sgi.com> <86802c440803301920o47335876yac12a5a09d1a8cc9@mail.gmail.com> <20080331123338.GA14636@elte.hu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1699 Lines: 44 On Mon, Mar 31, 2008 at 5:33 AM, Ingo Molnar wrote: > > > * Yinghai Lu wrote: > > > On Sun, Mar 30, 2008 at 7:18 PM, Jack Steiner wrote: > > > > > > > > if the calling path like GET_APIC_ID is keeping checking if it is > > > > UV box after boot time, that may not good. > > > > > > > > don't need make other hundreds of machine keep running the code > > > > only for several big box all the time. > > > > > > > > YH > > > > > > > > > I added trace code to see how often GET_APIC_ID() is called. For my > > > 8p AMD box, the function is called 6 times per cpu during boot. I > > > have not seen any other calls to the function after early boot > > > although I'm they occur under some circumstances. > > > > then it is ok. > > yes - and even if it were called more frequently, having generic code > and having the possibility of an as generic as possible kernel image > (and kernel rpms) is still a very important feature. In that sense > subarch support is actively harmful and we are trying to move away from > that model. regarding LinuxBIOS = coreboot + TinyKernel. some box need to use 64bit kernel, because 32 bit kernel could mess up the 64 bit resources, and final kernel kexeced is 64 bit. and TinyKernel need to stay with coreboot in MB flash rom, and that flash is about 2M... So hope it is easier to use MACRO to mask platform detect code out. YH -- 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/