From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262057AbVEXM37 (ORCPT ); Tue, 24 May 2005 08:29:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262038AbVEXM1k (ORCPT ); Tue, 24 May 2005 08:27:40 -0400 Received: from colin.muc.de ([193.149.48.1]:45326 "EHLO mail.muc.de") by vger.kernel.org with ESMTP id S262035AbVEXM1B (ORCPT ); Tue, 24 May 2005 08:27:01 -0400 Date: 24 May 2005 14:27:00 +0200 Date: Tue, 24 May 2005 14:27:00 +0200 From: Andi Kleen To: Ashok Raj Cc: akpm@osdl.org, zwane@arm.linux.org.uk, rusty@rustycorp.com.au, vatsa@in.ibm.com, shaohua.li@intel.com, linux-kernel@vger.kernel.org, discuss@x86-64.org Subject: Re: [patch 3/4] CPU Hotplug support for X86_64 Message-ID: <20050524122700.GC86182@muc.de> References: <20050524081113.409604000@csdlinux-2.jf.intel.com> <20050524081304.805933000@csdlinux-2.jf.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050524081304.805933000@csdlinux-2.jf.intel.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 24, 2005 at 01:11:16AM -0700, Ashok Raj wrote: > =================================================================== > --- linux-2.6.12-rc4-mm2.orig/arch/x86_64/kernel/smpboot.c > +++ linux-2.6.12-rc4-mm2/arch/x86_64/kernel/smpboot.c > @@ -62,9 +62,12 @@ > /* Number of siblings per CPU package */ > int smp_num_siblings = 1; > /* Package ID of each logical CPU */ > -u8 phys_proc_id[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID }; > -u8 cpu_core_id[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID }; > +u8 phys_proc_id[NR_CPUS] __cacheline_aligned = > + { [0 ... NR_CPUS-1] = BAD_APICID }; Why this change? > EXPORT_SYMBOL(phys_proc_id); > + > +u8 cpu_core_id[NR_CPUS] __cacheline_aligned = > + { [0 ... NR_CPUS-1] = BAD_APICID }; And that one? It does not seem related to CPUhotplug. May as a separate patch, but in this case the "per cpu readonly" section C.Lameter recently added should be used for these which are near always read-only (I hope the section made it into -mm* now) -Andi