From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756188AbYCKKLz (ORCPT ); Tue, 11 Mar 2008 06:11:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752277AbYCKKLq (ORCPT ); Tue, 11 Mar 2008 06:11:46 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:54617 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754378AbYCKKLp (ORCPT ); Tue, 11 Mar 2008 06:11:45 -0400 Date: Tue, 11 Mar 2008 11:11:26 +0100 From: Ingo Molnar To: Alexey Dobriyan Cc: Suresh Siddha , hpa@zytor.com, tglx@linutronix.de, andi@firstfloor.org, hch@infradead.org, linux-kernel@vger.kernel.org, Arjan van de Ven Subject: Re: [patch 1/2] x86, fpu: split FPU state from task struct - v5 Message-ID: <20080311101126.GY25110@elte.hu> References: <20080310222955.565902000@linux-os.sc.intel.com> <20080311050644.GB4589@martell.zuzino.mipt.ru> <20080311083517.GC25110@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Alexey Dobriyan wrote: > On 3/11/08, Ingo Molnar wrote: > > > > * Alexey Dobriyan wrote: > > > > > > - extern void __bad_fxsave_alignment(void); > > > > - > > > > - if (offsetof(struct task_struct, thread.i387.fxsave) & 15) > > > > - __bad_fxsave_alignment(); > > > > > > I think removal of such checks needs giving necessary alignment to > > > cache. Previously it worked because of __aligned((16)) and > > > L1_CACHE_SHIFT combo. > > > > it's still checked, just elsewhere: > > > > > + WARN_ON((unsigned long)dst->thread.xstate & 15); > > > > i'd not expect us to ever align worse than 16 bytes in the future > > But sysfs tells me alignment of "xstate" is 8 now. Object size is 512 > which is masking it. ok - you are right, that needs to be solved then. (object size could change anytime someone adds a few fields for debugging or whatever) Ingo