Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752770AbdF0QdD (ORCPT ); Tue, 27 Jun 2017 12:33:03 -0400 Received: from mail-qk0-f174.google.com ([209.85.220.174]:35577 "EHLO mail-qk0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751658AbdF0Qc6 (ORCPT ); Tue, 27 Jun 2017 12:32:58 -0400 Subject: Re: [PATCH V2 2/2] rt: Increase/decrease the nr of migratory tasks when enabling/disabling migration To: Henri Roosen , Daniel Bristot de Oliveira , linux-rt-users Cc: "Luis Claudio R . Goncalves" , Clark Williams , Luiz Capitulino , Sebastian Andrzej Siewior , Thomas Gleixner , Steven Rostedt , Peter Zijlstra , Ingo Molnar , LKML References: <94154431-a0b2-b106-8c23-519ce866271f@ginzinger.com> From: Daniel Bristot de Oliveira Message-ID: <998180d6-b4c5-bf04-1088-4d5055e4eaf1@redhat.com> Date: Tue, 27 Jun 2017 18:32:51 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.0 MIME-Version: 1.0 In-Reply-To: <94154431-a0b2-b106-8c23-519ce866271f@ginzinger.com> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 753 Lines: 20 On 06/27/2017 04:55 PM, Henri Roosen wrote: >> >> As rt_nr_migratory is unsigned, it will become > 0, notifying that the >> RQ is overloaded, activating pushing mechanism without need. > > What kind of symptoms might be triggered by this? I'm currently facing a > problem with a continuous-reboot-test where the kernel seems to hang > sometimes at a (seemingly) random place during kernel boot, on > 4.9.33-rt23 with iMX6Q. A back-port of this patch to 4.9-rt seems to fix > it. Or is it covering up a different problem? The side effect is notifying that the RQ is overloaded, activating pushing mechanism without need. I was not seeing system freezes because of it... but, just in case...do you have the console output from your board? -- Daniel