From owner-freebsd-current@FreeBSD.ORG Thu Sep 22 19:05:11 2005 Return-Path: X-Original-To: freebsd-current@FreeBSD.org Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 48BF216A41F; Thu, 22 Sep 2005 19:05:11 +0000 (GMT) (envelope-from jkim@FreeBSD.org) Received: from anuket.mj.niksun.com (gwnew.niksun.com [65.115.46.162]) by mx1.FreeBSD.org (Postfix) with ESMTP id E5AF843D60; Thu, 22 Sep 2005 19:05:07 +0000 (GMT) (envelope-from jkim@FreeBSD.org) Received: from niksun.com (anuket [10.70.0.5]) by anuket.mj.niksun.com (8.13.1/8.13.1) with ESMTP id j8MJB8gs026774; Thu, 22 Sep 2005 15:11:08 -0400 (EDT) (envelope-from jkim@FreeBSD.org) From: Jung-uk Kim To: freebsd-current@FreeBSD.org Date: Thu, 22 Sep 2005 15:04:38 -0400 User-Agent: KMail/1.6.2 References: <200509211550.27524.jkim@FreeBSD.org> <43325114.4090907@gneto.com> <43325364.8090208@freebsd.org> In-Reply-To: <43325364.8090208@freebsd.org> MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="euc-kr" Content-Transfer-Encoding: 7bit Message-Id: <200509221504.44919.jkim@FreeBSD.org> X-Virus-Scanned: ClamAV devel-20050919/1097/Wed Sep 21 14:56:51 2005 on anuket.mj.niksun.com X-Virus-Status: Clean Cc: Colin Percival Subject: Re: [PATCH] AMD multicore detection X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 22 Sep 2005 19:05:11 -0000 On Thursday 22 September 2005 02:47 am, Colin Percival wrote: > Martin Nilsson wrote: > > Jung-uk Kim wrote: > >> New patch is here: > >> http://people.freebsd.org/~jkim/multicore.diff > >> > >> Please test and let me know. I don't have multicore CPU to test > >> it for myself. :-( > > > > The below is on a Pentium D 820 (Dualcore). I don't like that the > > two cores are reported as hyperthreading when the CPU does not > > support hyperthreading (only the 840 EE does). If we ship 6.0 > > with HT disabled I'm afraid that it will turn off one of the > > cores, right? > > It shouldn't. Dual-core processors claim to be hyperthreaded, but > when I wrote the patch which disabled hyperthreading I added extra > (and rather complicated) code to detect dual-core processors and > *not* disable them. > > If I got it wrong, please let me know. :-) I think what's happening is this: /* * If the deterministic cache parameters are not * available, or if no caches were reported to exist, * just accept what the HTT flag indicated. */ if (hyperthreading_cpus == 0) hyperthreading_cpus = logical_cpus; I googled a bit and found this: http://crystalmark.info/BBS/c-board.cgi?cmd=one;no=726;id=report It's japanese but you will be able to read the report. ;-) cpuid with %eax = 4 doesn't seem to return anything. Jung-uk Kim > Colin Percival