Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932581Ab2F1HxV (ORCPT ); Thu, 28 Jun 2012 03:53:21 -0400 Received: from smtp.witbe.net ([81.88.96.48]:37615 "EHLO smtp.witbe.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932496Ab2F1HxT (ORCPT ); Thu, 28 Jun 2012 03:53:19 -0400 Date: Thu, 28 Jun 2012 09:51:03 +0200 From: Paul Rolland To: Tejun Heo Cc: Linux Kernel Mailing List , Jens Axboe Subject: Re: 3.5.0-rc3 - Issue with CFQ and cgroup Message-ID: <20120628095103.3c6c0a1e@tux.DEF.witbe.net> In-Reply-To: <20120627182202.GO15811@google.com> References: <20120627195808.31714295@tux.DEF.witbe.net> <20120627182202.GO15811@google.com> Organization: AS2917.net X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.7; x86_64-unknown-linux-gnu) Face: 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 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2664 Lines: 88 Hello, On Wed, 27 Jun 2012 11:22:02 -0700 Tejun Heo wrote: > Hello, > > > io scheduler noop registered > Can you please test the following branch? > > git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git > for-linus Well code is the same.... so is the result : [root@tux ~]# uname -a Linux tux.DEF.witbe.net 3.5.0-rc4-g6b16351 #1 SMP PREEMPT Thu Jun 28 09:11:07 CEST 2012 x86_64 x86_64 x86_64 GNU/Linux and ------------[ cut here ]------------ WARNING: at block/blk-cgroup.c:867 blkcg_policy_register+0xb5/0xc0() Hardware name: Vostro 1520 Modules linked in: Pid: 1, comm: swapper/0 Not tainted 3.5.0-rc4-g6b16351 #1 Call Trace: [] warn_slowpath_common+0x7a/0xb0 [] ? deadline_init+0x12/0x12 [] warn_slowpath_null+0x15/0x20 [] blkcg_policy_register+0xb5/0xc0 [] cfq_init+0x42/0x9f [] do_one_initcall+0x3a/0x160 [] kernel_init+0x137/0x1bb [] ? do_early_param+0x87/0x87 [] kernel_thread_helper+0x4/0x10 [] ? start_kernel+0x3b2/0x3b2 [] ? gs_change+0xb/0xb ---[ end trace 82bc55f036371117 ]--- and of course cfq is missing in : [root@tux ~]# cat /sys/block/sda/queue/scheduler [noop] deadline Looking at the code, it seems strange that cfq_init requires blkcg_policy_register to be successfull, wether you have defined CFQ_CGROUP_IOSCHED or not. So, I applied the following patch, and I now have: [root@tux ~]# cat /sys/block/sda/queue/scheduler noop deadline [cfq] Not sure this is the correct patch, but at least it works for me (tm) ;) Signed-Off-by: Paul Rolland diff -urN block/cfq-iosched.orig block/cfq-iosched.c --- block/cfq-iosched.orig 2012-06-28 09:39:06.000000000 +0200 +++ block/cfq-iosched.c 2012-06-28 09:39:31.000000000 +0200 @@ -4198,9 +4198,11 @@ cfq_group_idle = 0; #endif +#ifdef CONFIG_CFQ_GROUP_IOSCHED ret = blkcg_policy_register(&blkcg_policy_cfq); if (ret) return ret; +#endif cfq_pool = KMEM_CACHE(cfq_queue, 0); if (!cfq_pool) @@ -4215,7 +4217,9 @@ err_free_pool: kmem_cache_destroy(cfq_pool); err_pol_unreg: +#ifdef CONFIG_CFQ_GROUP_IOSCHED blkcg_policy_unregister(&blkcg_policy_cfq); +#endif return ret; } Paul -- 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/