From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754050AbcGLRFO (ORCPT ); Tue, 12 Jul 2016 13:05:14 -0400 Received: from mail-pa0-f51.google.com ([209.85.220.51]:36254 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751177AbcGLRFL (ORCPT ); Tue, 12 Jul 2016 13:05:11 -0400 Date: Tue, 12 Jul 2016 10:04:59 -0700 From: Viresh Kumar To: Petr Mladek Cc: Sergey Senozhatsky , Andrew Morton , Jan Kara , Tejun Heo , Tetsuo Handa , "linux-kernel@vger.kernel.org" , Byungchul Park , Sergey Senozhatsky Subject: Re: [PATCH v12 0/3] printk: Make printk() completely async Message-ID: <20160712170459.GC4695@ubuntu> References: <20160513131848.2087-1-sergey.senozhatsky@gmail.com> <20160712155918.GC8597@pathway.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160712155918.GC8597@pathway.suse.cz> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12-07-16, 17:59, Petr Mladek wrote: > On Mon 2016-07-11 12:25:11, Viresh Kumar wrote: > > We were also screwed because of the problem this thread is trying to solve, > > which I posted last week [1]. > > > > And then I found this thread which fixed my issue, thanks a lot guys :) > > > > Tested-by: Viresh Kumar > > > > Though, I would also like to mention one unwanted thing that happened on > > my setup :) > > > > [ 12.874909] sched: RT throttling activated for rt_rq ffffffc0ac13fcd0 (cpu 0) > > [ 12.874909] potential CPU hogs: > > [ 12.874909] printk (292) > > > > On my system, the excessive printing happens during suspend/resume and this > > happened after all the non-boot CPUs were offlined. So, only CPU 0 was left and > > that was doing printing for a long time and so these errors :) > > > > It resulted in missing some print messages eventually as the scheduler probably > > didn't schedule this thread for sometime after that. > > > > Will it be fine to get the priority of this kthread to a somewhat lower value, > > etc ? > > I think that this patch helped only by chance. Sorry got confused a bit here.. Which patch are you taking about here ? As you replied below my message, I believe that you are talking about the 3 patches that were posted in this series. But the rest of your comment looks like the fourth fixup patch that Sergey shared :) So, the fixup patch doesn't fix any issues in my case, to make it clear. I still have my system hanging somewhere. > I am still scratching my head about the problem fixed by this patch > and also about suspend problems. :) -- viresh