From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754290AbZHYJGA (ORCPT ); Tue, 25 Aug 2009 05:06:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752771AbZHYJF7 (ORCPT ); Tue, 25 Aug 2009 05:05:59 -0400 Received: from nef2.ens.fr ([129.199.96.40]:4504 "EHLO nef2.ens.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751682AbZHYJF6 (ORCPT ); Tue, 25 Aug 2009 05:05:58 -0400 X-Greylist: delayed 944 seconds by postgrey-1.27 at vger.kernel.org; Tue, 25 Aug 2009 05:05:56 EDT Date: Tue, 25 Aug 2009 10:50:13 +0200 From: Nicolas George To: linux-kernel@vger.kernel.org, cpufreq@vger.kernel.org Subject: [cpufreq] Autoloading governors blocks Message-ID: <20090825085013.GA7577@phare.normalesup.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="tKW2IUtsqtDRztdT" Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.1.4 (nef2.ens.fr [129.199.96.32]); Tue, 25 Aug 2009 10:50:13 +0200 (CEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --tKW2IUtsqtDRztdT Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi. Yesterday, on a freshly-compiled 2.6.30.5 kernel, I noticed that changing to a governor that exists as a module but is not loaded causes the process that did the change to go to state D, along with any process later accessing the cpufreq nodes. The CPU is a Thurion64, working with powernow-k8. The kernel is configured with CONFIG_X86_64, CONFIG_PREEMPT, CONFIG_NO_HZ. The governor, at the time the problem happened, was ondemand. The problem happened either when loading powersave or userspace. On the other hand, selecting a governor that is already loaded works fine, and trying to autoload a governor that does not exist fails normally. I do not have a lot of time to investigate, I hope this bug report may be useful. Regards, --=20 Nicolas George [34560.087058] INFO: task kondemand/0:5412 blocked for more than 120 second= s. [34560.087066] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables = this message. [34560.087073] kondemand/0 D 0000000000000000 0 5412 2 [34560.087084] ffffffff80586380 0000000000000046 0000000000000001 ffff8800= 3c9fed30 [34560.087094] ffff88003c9fefd8 ffff88003c9fefd8 ffffffff80596700 ffffffff= 80596f20 [34560.087104] ffff88003f853a00 ffff88003c9fed30 ffffffff805cbec0 ffffffff= a02f1b00 [34560.087113] Call Trace: [34560.087150] [] ? do_dbs_timer+0x0/0x320 [cpufreq_onde= mand] [34560.087162] [] ? schedule+0x13/0x40 [34560.087172] [] ? __down_write_nested+0x85/0xe0 [34560.087186] [] ? lock_policy_rwsem_write+0x18/0x40 [34560.087199] [] ? do_dbs_timer+0x6f/0x320 [cpufreq_ond= emand] [34560.087215] [] ? do_dbs_timer+0x0/0x320 [cpufreq_onde= mand] [34560.087226] [] ? worker_thread+0x19c/0x2c0 [34560.087234] [] ? autoremove_wake_function+0x0/0x30 [34560.087243] [] ? worker_thread+0x0/0x2c0 [34560.087251] [] ? worker_thread+0x0/0x2c0 [34560.087259] [] ? kthread+0x4e/0x90 [34560.087267] [] ? child_rip+0xa/0x20 [34560.087275] [] ? kthread+0x0/0x90 [34560.087282] [] ? child_rip+0x0/0x20 [34560.087310] INFO: task cpufreq-set:25132 blocked for more than 120 secon= ds. [34560.087315] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables = this message. [34560.087320] cpufreq-set D 0000000000000000 0 25132 1 [34560.087329] ffff880030d8c110 0000000000000082 0000000000000092 ffff8800= 3d014d70 [34560.087338] ffff88003d015018 ffff88003d015018 ffff88003e467e48 7fffffff= ffffffff [34560.087348] ffff88003e467bb8 7fffffffffffffff 7fffffffffffffff 00000000= 00000000 [34560.087357] Call Trace: [34560.087367] [] ? schedule+0x13/0x40 [34560.087376] [] ? schedule_timeout+0x175/0x1c0 [34560.087385] [] ? call_usermodehelper_exec+0x8d/0xd0 [34560.087394] [] ? wait_for_common+0x15a/0x1a0 [34560.087404] [] ? default_wake_function+0x0/0x10 [34560.087413] [] ? __wake_up+0x54/0xb0 [34560.087425] [] ? __cancel_work_timer+0x16a/0x1d0 [34560.087434] [] ? wq_barrier_func+0x0/0x10 [34560.087448] [] ? cpufreq_governor_dbs+0xa1/0x2bc [cpu= freq_ondemand] [34560.087458] [] ? __cpufreq_governor+0xc9/0x130 [34560.087468] [] ? __cpufreq_set_policy+0x122/0x180 [34560.087477] [] ? store_scaling_governor+0xff/0x280 [34560.087486] [] ? handle_update+0x0/0x10 [34560.087498] [] ? store+0x6b/0xa0 [34560.087507] [] ? sysfs_write_file+0xce/0x160 [34560.087517] [] ? vfs_write+0xc9/0x170 [34560.087526] [] ? sys_write+0x53/0xa0 [34560.087534] [] ? system_call_fastpath+0x16/0x1b --tKW2IUtsqtDRztdT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkqTpcUACgkQsGPZlzblTJO1zQCff00WLqJT7pp+DDc3n1vDZkGK hksAnjO9RpRHnY2g/Q6d4R3RUqwQIdc2 =Lmdj -----END PGP SIGNATURE----- --tKW2IUtsqtDRztdT--