From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752535AbbEGK7H (ORCPT ); Thu, 7 May 2015 06:59:07 -0400 Received: from mail.skyhub.de ([78.46.96.112]:55003 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751511AbbEGK7F (ORCPT ); Thu, 7 May 2015 06:59:05 -0400 Date: Thu, 7 May 2015 12:59:00 +0200 From: Borislav Petkov To: Dave Hansen Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Andy Lutomirski , Fenghua Yu , "H. Peter Anvin" , Linus Torvalds , Oleg Nesterov , Thomas Gleixner Subject: Re: [PATCH 084/208] x86/fpu: Rename xsave.header::xstate_bv to 'xfeatures' Message-ID: <20150507105859.GH6859@pd.tnic> References: <1430848300-27877-1-git-send-email-mingo@kernel.org> <1430848300-27877-6-git-send-email-mingo@kernel.org> <554904A6.8040503@linux.intel.com> <20150505181613.GA28562@gmail.com> <55490B1F.3080409@linux.intel.com> <20150506061603.GA13720@gmail.com> <554A5D23.2030405@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <554A5D23.2030405@linux.intel.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 06, 2015 at 11:27:47AM -0700, Dave Hansen wrote: > But we'd need to get to a point where we are calling 'xsaves' with a > Requested Feature BitMask (aka RFBM[]) that had holes in it. As it > stands today, we always call it with RFBM=-1 and so we always have > XCOMP_BV = XCR0. > > We'd need to determine which fields are in the init state before we do > an xsaves. Btw, do we have any perf data as to the improvement the compacted variant brings? I mean, it means a bunch of jumping through hoops in SW but is it worth it? Thanks. -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. --