Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934115AbZAPAxc (ORCPT ); Thu, 15 Jan 2009 19:53:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754810AbZAPAxW (ORCPT ); Thu, 15 Jan 2009 19:53:22 -0500 Received: from mail.klingt.org ([86.59.21.178]:37581 "EHLO klingt.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755164AbZAPAxV (ORCPT ); Thu, 15 Jan 2009 19:53:21 -0500 Subject: Re: 2.6.28-rc9: oprofile regression From: Tim Blechmann To: Thomas Gleixner Cc: Andi Kleen , oprofile-list@lists.sf.net, linux-kernel@vger.kernel.org, Robert Richter , venkatesh.pallipadi@intel.com In-Reply-To: References: <1229869416.6911.1.camel@thinkpad> <1229894585.6898.6.camel@thinkpad> <49544497.9020900@linux.intel.com> <1230894257.6072.10.camel@thinkpad> <1231957184.13033.70.camel@thinkpad> <1232010853.6541.4.camel@thinkpad> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-Xp16/VUeoITDrlvq7Qc6" Date: Fri, 16 Jan 2009 01:53:01 +0100 Message-Id: <1232067181.6134.74.camel@thinkpad> Mime-Version: 1.0 X-Mailer: Evolution 2.24.2 X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-3.0 (klingt.org [127.0.0.1]); Fri, 16 Jan 2009 01:53:03 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2378 Lines: 72 --=-Xp16/VUeoITDrlvq7Qc6 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Thu, 2009-01-15 at 21:37 +0100, Thomas Gleixner wrote: > On Thu, 15 Jan 2009, Tim Blechmann wrote: > > On Thu, 2009-01-15 at 09:46 +0100, Thomas Gleixner wrote: > > > Tim, > > >=20 > > > On Wed, 14 Jan 2009, Tim Blechmann wrote: > > > > this code (line 81/82), changes counter_width from 32 to 40. > > > >=20 > > > > if (counter_width < eax.split.bit_width) > > > > counter_width =3D eax.split.bit_width; > > > >=20 > > > > however when removing these lines, and thus keeping the value 32 fo= r > > > > counter_width, doesn't change the behavior, only one NMI per cpu. > > >=20 > > > It would only help, when the reported bit_width would be bogus. We > > > know that you get at least one NMI, so lets look at the results we ge= t > > > there. > >=20 > > it seems, that ppro_check_ctrs is never called: > > [ 982.238639] oprofile: using NMI interrupt. > >=20 > > hth, tim >=20 > Hmm, that confuses the hell out of me. Can you try the patch below, > which restores the original code of writing the counter registers ? no difference ... i must admit, i already spent some time, trying to revert the specific changes of this commit ... i gave up to wait for some help from someone, who actually knows how the code is working ... possibly it makes sense to compile a full kernel of the first bad kommit and introduce the different changes one by one ... i will try to find some time for this during the next few days ... but if you have more patches, that i can test, please let me know ... cheers, tim =20 -- tim@klingt.org http://tim.klingt.org Which is more musical, a truck passing by a factory or a truck passing by a music school? John Cage --=-Xp16/VUeoITDrlvq7Qc6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAklv2msACgkQdL+4qsZfVssuiQCeLwaBrk0KtxJ1+8EWU7KMJe9Z VoYAnAsgByctKiCplVGSvK9f+c3NN+J+ =H5JJ -----END PGP SIGNATURE----- --=-Xp16/VUeoITDrlvq7Qc6-- -- 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/