From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751377AbVJLVsm (ORCPT ); Wed, 12 Oct 2005 17:48:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751505AbVJLVsm (ORCPT ); Wed, 12 Oct 2005 17:48:42 -0400 Received: from mx1.suse.de ([195.135.220.2]:54411 "EHLO mx1.suse.de") by vger.kernel.org with ESMTP id S1751486AbVJLVsl (ORCPT ); Wed, 12 Oct 2005 17:48:41 -0400 From: Andi Kleen To: discuss@x86-64.org Subject: Re: [discuss] [Patch 1/2] x86, x86_64: Intel HT, Multi core detection fixes Date: Wed, 12 Oct 2005 23:49:04 +0200 User-Agent: KMail/1.8.2 Cc: "Siddha, Suresh B" , linux-kernel@vger.kernel.org, akpm@osdl.org References: <20051005161706.B30098@unix-os.sc.intel.com> <200510081228.39492.ak@suse.de> <20051012143641.B29292@unix-os.sc.intel.com> In-Reply-To: <20051012143641.B29292@unix-os.sc.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200510122349.05312.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 12 October 2005 23:36, Siddha, Suresh B wrote: > Fields obtained through cpuid vector 0x1(ebx[16:23]) and > vector 0x4(eax[14:25], eax[26:31]) indicate the maximum values and might not > always be the same as what is available and what OS sees. So make sure > "siblings" and "cpu cores" values in /proc/cpuinfo reflect the values as seen > by OS instead of what cpuid instruction says. This will also fix the buggy BIOS > cases (for example where cpuid on a single core cpu says there are "2" siblings, > even when HT is disabled in the BIOS. > http://bugzilla.kernel.org/show_bug.cgi?id=4359) I'm not too fond of this new booted_core variable. How about you just put the true number of cores into x86_num_cores? What should x86_num_cores be in your setup anyways if not "booted cores"? Also I must admit the number of different variables to keep track of multicore and siblingness starts to become mindboggling, so I would recommend you add a fat overview comment somewhere that describes their definition and relationship. Or better put something into Documentation, it is probably as confusing for user space /proc/cpuinfo consumer too. -Andi