Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756943AbYKDQ6w (ORCPT ); Tue, 4 Nov 2008 11:58:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754098AbYKDQ6n (ORCPT ); Tue, 4 Nov 2008 11:58:43 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:42420 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752404AbYKDQ6m (ORCPT ); Tue, 4 Nov 2008 11:58:42 -0500 Date: Tue, 4 Nov 2008 17:58:11 +0100 From: Ingo Molnar To: Cyrill Gorcunov Cc: Alexander van Heukelum , Alexander van Heukelum , LKML , Thomas Gleixner , "H. Peter Anvin" , lguest@ozlabs.org, jeremy@xensource.com, Steven Rostedt , Mike Travis , Jeremy Fitzhardinge , Andi Kleen Subject: Re: [PATCH RFC/RFB] x86_64, i386: interrupt dispatch changes Message-ID: <20081104165811.GA1664@elte.hu> References: <20081104122839.GA22864@mailshack.com> <20081104124242.GA6795@elte.hu> <1225805399.25337.1282903253@webmail.messagingengine.com> <20081104140030.GA16178@elte.hu> <1225815789.30706.1282936457@webmail.messagingengine.com> <20081104164717.GD21470@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081104164717.GD21470@localhost> User-Agent: Mutt/1.5.18 (2008-05-17) 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,DNS_FROM_SECURITYSAGE autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] 0.0 DNS_FROM_SECURITYSAGE RBL: Envelope sender in blackholes.securitysage.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 997 Lines: 27 * Cyrill Gorcunov wrote: > [Alexander van Heukelum - Tue, Nov 04, 2008 at 05:23:09PM +0100] > ... > | > | I did some timings using the little program below (32-bit only), doing > | 1024 times the same sequence. TEST1 is just pushing a constant onto > | the stack; TEST2 is pushing the cs register; TEST3 is the sequence > | from the patch to extract the vector number from the cs register. > | > | Opteron (cycles): 1024 / 1157 / 3527 > | Xeon E5345 (cycles): 1092 / 1085 / 6622 > | Athlon XP (cycles): 1028 / 1166 / 5192 > > Xeon is defenitely out of luck :-) it's still OK - i.e. no outrageous showstopper overhead anywhere in that instruction sequence. The total round-trip overhead is what will matter most. Ingo -- 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/