Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030406AbbEETWe (ORCPT ); Tue, 5 May 2015 15:22:34 -0400 Received: from mail.skyhub.de ([78.46.96.112]:53157 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757223AbbEETW3 (ORCPT ); Tue, 5 May 2015 15:22:29 -0400 Date: Tue, 5 May 2015 21:22:25 +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 207/208] x86/fpu: Add FPU performance measurement subsystem Message-ID: <20150505192225.GP3910@pd.tnic> References: <1430848712-28064-1-git-send-email-mingo@kernel.org> <1430848712-28064-47-git-send-email-mingo@kernel.org> <554916B4.1040809@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <554916B4.1040809@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 Content-Length: 985 Lines: 25 On Tue, May 05, 2015 at 12:15:00PM -0700, Dave Hansen wrote: > On 05/05/2015 10:58 AM, Ingo Molnar wrote: > > x86/fpu: Cost of: XSAVE insn : 104 cycles > > x86/fpu: Cost of: XRSTOR insn : 80 cycles > > Isn't there going to be pretty huge variability here depending on how > much state you are xsave/xrstor'ing and if the init/modified > optimizations are in play? If this is a module, one could modprobe/rmmod it multiple times for an average. But yeah, it would depend in the end on what the system does/has been doing in the recent past and thus how much state has been "accumulated". -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/