From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yong Zhang Subject: Re: Tasks schedule/migration issue with CPU hotplug? Date: Thu, 8 Sep 2011 15:39:43 +0800 Message-ID: <20110908073943.GC11124@zhy> References: <20110908072801.GA11124@zhy> Reply-To: Yong Zhang Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20110908072801.GA11124@zhy> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: TAO HU Cc: peterz@infradead.org, Ingo Molnar , linux-omap , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-omap@vger.kernel.org On Thu, Sep 08, 2011 at 03:28:01PM +0800, Yong Zhang wrote: > On Thu, Sep 08, 2011 at 02:47:08PM +0800, TAO HU wrote: > > Resend with linux-kernel mail list included. > > Hmm, could you give a try with commit da7a735e? > > Thanks, > Yong > > --- > commit da7a735e51f9622eb3e1672594d4a41da01d7e4f > Author: Peter Zijlstra > Date: Mon Jan 17 17:03:27 2011 +0100 > > sched: Fix switch_from_fair() > > When a task is taken out of the fair class we must ensure the vruntime > is properly normalized because when we put it back in it will assume > to be normalized. > > The case that goes wrong is when changing away from the fair class > while sleeping. Sleeping tasks have non-normalized vruntime in order > to make sleeper-fairness work. So treat the switch away from fair as a > wakeup and preserve the relative vruntime. > > Also update sysrq-n to call the ->switch_{to,from} methods. > > Reported-by: Onkalo Samu > Signed-off-by: Peter Zijlstra > LKML-Reference: > Signed-off-by: Ingo Molnar > > > > > On Wed, Sep 7, 2011 at 10:22 PM, TAO HU wrote: > > > <4>[ 6950.136230] cfs_rq[0]:/ > > > <4>[ 6950.136230] ? .exec_clock ? ? ? ? ? ? ? ? ? ?: 6520265.283900 > > > <4>[ 6950.136260] ? .MIN_vruntime ? ? ? ? ? ? ? ? ?: 2223057.428522 > > > <4>[ 6950.136260] ? .min_vruntime ? ? ? ? ? ? ? ? ?: 2223057.428522 > > > <4>[ 6950.136291] ? .max_vruntime ? ? ? ? ? ? ? ? ?: 2223114.709956 > > > <4>[ 6950.136291] ? .spread ? ? ? ? ? ? ? ? ? ? ? ?: 57.281434 > > > <4>[ 6950.136291] ? .spread0 ? ? ? ? ? ? ? ? ? ? ? : 0.000000 > > > <4>[ 6950.136322] ? .nr_running ? ? ? ? ? ? ? ? ? ?: 212 > > > <4>[ 6950.136322] ? .load ? ? ? ? ? ? ? ? ? ? ? ? ?: 217650 > > > <4>[ 6950.136352] ? .nr_spread_over ? ? ? ? ? ? ? ?: 125034 > > > <4>[ 6950.136352] ? .shares ? ? ? ? ? ? ? ? ? ? ? ?: 0 > > > <4>[ 6950.136352] > > > <4>[ 6950.136566] runnable tasks: > > > <4>[ 6950.136566] ? ? ? ? ? ? task ? PID ? ? ? ? tree-key ?switches > > > prio ? ? exec-runtime ? ? ? ? sum-exec ? ? ? ?sum-sleep > > > <4>[ 6950.136596] > > > ---------------------------------------------------------------------------------------------------------- > > > <4>[ 6950.136627] ? ? ?omap2_mcspi ? ?21 ? 2223062.886210 ?29451523 The tree-key(2223062.886210) almost equals to cfs_rq.min_vruntime, so maybe you hit the bug which is cured by the mentioned commit. Thanks, Yong