Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757310AbXEIUOc (ORCPT ); Wed, 9 May 2007 16:14:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754958AbXEIUOZ (ORCPT ); Wed, 9 May 2007 16:14:25 -0400 Received: from turing-police.cc.vt.edu ([128.173.14.107]:53354 "EHLO turing-police.cc.vt.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751744AbXEIUOY (ORCPT ); Wed, 9 May 2007 16:14:24 -0400 X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.2 To: Jeremy Fitzhardinge Cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: 2.6.21-mm2 - 100% CPU on ksoftirqd/1 In-Reply-To: Your message of "Wed, 09 May 2007 11:12:39 PDT." <46420F17.2050106@goop.org> From: Valdis.Kletnieks@vt.edu References: <20070509012322.199f292b.akpm@linux-foundation.org> <4123.1178726923@turing-police.cc.vt.edu> <46420F17.2050106@goop.org> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1178741608_3418P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Wed, 09 May 2007 16:13:29 -0400 Message-ID: <15321.1178741609@turing-police.cc.vt.edu> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1342 Lines: 36 --==_Exmh_1178741608_3418P Content-Type: text/plain; charset=us-ascii On Wed, 09 May 2007 11:12:39 PDT, Jeremy Fitzhardinge said: > It always seems to happen on the last CPU; when I run the kernel as Xen > guest with 4 vcpus, it happens on events/3. Probably something different - at least once, I've caught it on /0 with 2 real cores online (T7200). Looking at kernel/softirq.c, the ksoftirqd() function is basically 2 nested while() loops. Looks like either local_softirq_pending() gets stuck true, but no obvious reason why, or something odd is getting set in the current-> structure so when we call schedule(), we end up returning rather than hitting the idle loop. Off to go see how much mm-bisect I can do before dinnertime - the rest will be later tonight... --==_Exmh_1178741608_3418P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQFGQitocC3lWbTT17ARAttRAJ0RtvzCMgBmp05GnEtWpO3xjns4zQCfcnub jQBTAP6bgUYml7aV43QwBfA= =ppyi -----END PGP SIGNATURE----- --==_Exmh_1178741608_3418P-- - 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/