Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756912AbYGIOwd (ORCPT ); Wed, 9 Jul 2008 10:52:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752916AbYGIOwZ (ORCPT ); Wed, 9 Jul 2008 10:52:25 -0400 Received: from metis.extern.pengutronix.de ([83.236.181.26]:51976 "EHLO metis.extern.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752205AbYGIOwY (ORCPT ); Wed, 9 Jul 2008 10:52:24 -0400 Date: Wed, 9 Jul 2008 16:52:17 +0200 From: Luotao Fu To: Wolfgang Grandegger Cc: Luotao Fu , Steven Rostedt , "Paul E. McKenney" , LKML , RT , Ingo Molnar , Thomas Gleixner Subject: Re: 2.6.24-rc8-rt1: Strange latencies on mpc5200 powerpc - RCU issue? Message-ID: <20080709145217.GB30586@pengutronix.de> Mail-Followup-To: Wolfgang Grandegger , Luotao Fu , Steven Rostedt , "Paul E. McKenney" , LKML , RT , Ingo Molnar , Thomas Gleixner References: <486A3EBB.6030905@grandegger.com> <486A573E.60107@grandegger.com> <486B607F.9040903@grandegger.com> <48709348.6000101@grandegger.com> <20080708150826.GA30586@pengutronix.de> <4873C363.3070306@grandegger.com> <4874B4C0.5090500@pengutronix.de> <4874B9D5.1020309@grandegger.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ncSAzJYg3Aa9+CRW" Content-Disposition: inline In-Reply-To: <4874B9D5.1020309@grandegger.com> X-PGP-Key-ID: 0xE5325261 X-URL: http://www.pengutronix.de/ X-Sent-From: Pengutronix Entwicklungszentrum Nord - Hildesheim X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Impressum: Pengutronix - Linux Solutions for Science and Industry Handelsregister: Amtsgericht Hildesheim, HRA 2686 Hannoversche Str. 2, 31134 Hildesheim, Germany Phone: +49-5121-206917-0 | Fax: +49-5121-206917-9 Inhaber: Dipl.-Ing. Robert Schwebel X-Message-Flag: See Message Headers for Impressum X-Uptime: 15:27:42 up 2 days, 5:07, 2 users, load average: 0.05, 0.08, 0.08 User-Agent: Mutt/1.5.17+20080114 (2008-01-14) X-SA-Exim-Connect-IP: 10.1.0.86 X-SA-Exim-Mail-From: l.fu@pengutronix.de X-SA-Exim-Scanned: No (on metis.extern.pengutronix.de); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1505 Lines: 53 --ncSAzJYg3Aa9+CRW Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Wolfgang, On Wed, Jul 09, 2008 at 03:15:01PM +0200, Wolfgang Grandegger wrote: > Hi Fu (without n) > =2E... > OK, in the past you have been able to reproduce the high latencies with = =20 > 2.6.24-rt1 and CONFIG_RCU_TRACE disabled, IIRC. Did you use a different = =20 > toolchain at that time? > Nope. As mentioned above, trace_mark() does some "real" works (what ever it= is.), while the new mechahnismen use flags to remember the state of preemption. M= aybe something here got optimized away? I take for grant, that you use gcc in yo= ur toolchain. Which version do you have? cheers Fu --=20 Dipl.-Ing. Luotao Fu | Phone: +49-5121-206917-3 Pengutronix - Linux Solutions for Science and Industry Entwicklungszentrum Nord http://www.pengutronix.de --ncSAzJYg3Aa9+CRW Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFIdNChiruQY+UyUmERAu8/AJ0VXl1MceCxuan2VnqdWQanUD4kngCbBWH/ Yk+9LbLLB8xFC8AM/XJ7v/s= =0sZ/ -----END PGP SIGNATURE----- --ncSAzJYg3Aa9+CRW-- -- 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/