From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757353AbZEHDSS (ORCPT ); Thu, 7 May 2009 23:18:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754238AbZEHDSG (ORCPT ); Thu, 7 May 2009 23:18:06 -0400 Received: from victor.provo.novell.com ([137.65.250.26]:34484 "EHLO victor.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753752AbZEHDSE (ORCPT ); Thu, 7 May 2009 23:18:04 -0400 Message-ID: <4A03A45D.2050102@novell.com> Date: Thu, 07 May 2009 23:17:49 -0400 From: Gregory Haskins User-Agent: Thunderbird 2.0.0.21 (Macintosh/20090302) MIME-Version: 1.0 To: Marcelo Tosatti CC: Chris Wright , Gregory Haskins , Avi Kivity , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Anthony Liguori Subject: Re: [RFC PATCH 0/3] generic hypercall support References: <4A0041BA.6060106@novell.com> <4A004676.4050604@redhat.com> <4A0049CD.3080003@gmail.com> <20090505231718.GT3036@sequoia.sous-sol.org> <4A010927.6020207@novell.com> <20090506072212.GV3036@sequoia.sous-sol.org> <4A018DF2.6010301@novell.com> <20090506160712.GW3036@sequoia.sous-sol.org> <4A031471.7000406@novell.com> <20090507233503.GA9103@amt.cnet> <20090507234311.GA9517@amt.cnet> In-Reply-To: <20090507234311.GA9517@amt.cnet> X-Enigmail-Version: 0.95.7 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig2791DD40DCC0F1447AFC6F7F" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig2791DD40DCC0F1447AFC6F7F Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Marcelo Tosatti wrote: > On Thu, May 07, 2009 at 08:35:03PM -0300, Marcelo Tosatti wrote: > =20 >> Also for PIO/MMIO you're adding this unoptimized lookup to the=20 >> measurement: >> >> pio_dev =3D vcpu_find_pio_dev(vcpu, port, size, !in); >> if (pio_dev) { >> kernel_pio(pio_dev, vcpu, vcpu->arch.pio_data); >> complete_pio(vcpu);=20 >> return 1; >> } >> >> Whereas for hypercall measurement you don't. I believe a fair comparis= on >> would be have a shared guest/host memory area where you store guest/ho= st >> TSC values and then do, on guest: >> >> rdtscll(&shared_area->guest_tsc); >> pio/mmio/hypercall >> ... back to host >> rdtscll(&shared_area->host_tsc); >> >> And then calculate the difference (minus guests TSC_OFFSET of course)?= >> =20 > > Test Machine: Dell Precision 490 - 4-way SMP (2x2) x86_64 "Woodcrest" > Core2 Xeon 5130 @2.00Ghz, 4GB RAM. > > Also it would be interesting to see the MMIO comparison with EPT/NPT, > it probably sucks much less than what you're seeing. > > =20 Agreed. If you or someone on this thread has such a beast, please fire up my test and post the numbers. -Greg --------------enig2791DD40DCC0F1447AFC6F7F Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.11 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkoDpF0ACgkQlOSOBdgZUxkOUACbBSnwGgsdlFH2x6Ab2x05GIiU vqUAn1T5M01EIakX7kxl5vTXhWaGKGDt =X7zr -----END PGP SIGNATURE----- --------------enig2791DD40DCC0F1447AFC6F7F--