From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756890Ab1HEW5I (ORCPT ); Fri, 5 Aug 2011 18:57:08 -0400 Received: from terminus.zytor.com ([198.137.202.10]:44269 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756868Ab1HEW5F (ORCPT ); Fri, 5 Aug 2011 18:57:05 -0400 Message-ID: <4E3C7520.1060808@zytor.com> Date: Fri, 05 Aug 2011 15:56:32 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:5.0) Gecko/20110707 Thunderbird/5.0 MIME-Version: 1.0 To: Borislav Petkov CC: Ingo Molnar , Thomas Gleixner , Linus Torvalds , Andrew Morton , Avi Kivity , "Przywara, Andre" , "Pohlack, Martin" , LKML Subject: Re: [PATCH -v3.2 3/3] x86, AMD: Move BSP code to cpu_dev helper References: <1312550110-24160-1-git-send-email-bp@amd64.org> <4E3C2405.8090309@zytor.com> <20110805175522.GA26217@aftab> <20110805180409.GC26217@aftab> <4E3C4D8C.1010709@zytor.com> <20110805225207.GA27866@aftab> In-Reply-To: <20110805225207.GA27866@aftab> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/05/2011 03:52 PM, Borislav Petkov wrote: > On Fri, Aug 05, 2011 at 04:07:40PM -0400, H. Peter Anvin wrote: >> On 08/05/2011 11:04 AM, Borislav Petkov wrote: >>> Move code which is run once on the BSP during boot into the cpu_dev >>> helper. >>> +static void __cpuinit bsp_init_amd(struct cpuinfo_x86 *c) >>> +{ >>> + if (static_cpu_has(X86_FEATURE_CONSTANT_TSC)) { >>> + >> >> You can't use static_cpu_has() here, since this code runs before >> alternatives -- it will always be false. Furthermore, for code that >> only runs once, it is never a win to do patching. > > Oh crap, this is a leftover from when run_on_bsp was struct > x86_cpuinit_ops member with no args. And I f*cked it up even then > although I went and got myself a pointer to boot_cpu_data: > I fixed it up directly. > >> Arguably bsp_init should be __init and not __cpuinit, but I don't know >> how to make that work with the machinery, and is something that can be >> fixed anyway. > > Yeah, how do we do that? struct cpu_dev is __cpuinitconst, > x86_cpuinit_ops is __cpuinitdata. > > We could add it to identify_boot_cpu() - there's already some per-vendor > stuff like init_amd_e400_c1e_mask() which wouldn't hurt to be behind a > vendor check. early_identify_cpu() does already the vendor check with > get_cpu_vendor() so later, in identify_cpu() we could add a run_on_bsp() > which is __init and switch/case on the ->x86_vendor inside. > > Then we can collect all the run-once-on-the-BSP code in there. > > Hmmm.. > As I said, we can fix this up incrementally. -hpa