From mboxrd@z Thu Jan 1 00:00:00 1970 From: Darren Hart Subject: Re: 2.6.33.[56]-rt23: howto create repeatable explosion in wakeup_next_waiter() Date: Thu, 08 Jul 2010 07:12:15 -0700 Message-ID: <4C35DCBF.9070109@us.ibm.com> References: <1278478019.10245.77.camel@marge.simson.net> <4C348940.9070805@us.ibm.com> <1278590730.10399.3.camel@marge.simson.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Thomas Gleixner , linux-rt-users , Peter Zijlstra To: Mike Galbraith Return-path: Received: from e36.co.us.ibm.com ([32.97.110.154]:53753 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755282Ab0GHOMv (ORCPT ); Thu, 8 Jul 2010 10:12:51 -0400 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e36.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id o68E9Ll6029392 for ; Thu, 8 Jul 2010 08:09:21 -0600 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay04.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o68ECYDl111308 for ; Thu, 8 Jul 2010 08:12:35 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id o68ECKMn025430 for ; Thu, 8 Jul 2010 08:12:21 -0600 In-Reply-To: <1278590730.10399.3.camel@marge.simson.net> Sender: linux-rt-users-owner@vger.kernel.org List-ID: On 07/08/2010 05:05 AM, Mike Galbraith wrote: > On Wed, 2010-07-07 at 07:03 -0700, Darren Hart wrote: > >> I see kernel version is: 2.6.33.6-rt23, have you reproduced this on >> earlier kernel versions as well? Any 2.6.31 rt kernel would be a good >> data point. > > FUTEX_CMP/WAIT_REQUEUE_PI first appeared in 2.6.29-rt, as does the > explosion. > Right. I haven't had a chance to look into this yet. I will have some time today. -- Darren Hart IBM Linux Technology Center Real-Time Linux Team