From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755893AbaCTKIz (ORCPT ); Thu, 20 Mar 2014 06:08:55 -0400 Received: from e28smtp06.in.ibm.com ([122.248.162.6]:37446 "EHLO e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751449AbaCTKIy (ORCPT ); Thu, 20 Mar 2014 06:08:54 -0400 Date: Thu, 20 Mar 2014 15:38:48 +0530 From: Srikar Dronamraju To: Davidlohr Bueso Cc: Peter Zijlstra , torvalds@linux-foundation.org, LKML , paulus@samba.org, tglx@linutronix.de, Paul McKenney , linuxppc-dev@lists.ozlabs.org, mingo@kernel.org Subject: Re: Tasks stuck in futex code (in 3.14-rc6) Message-ID: <20140320100848.GC10406@linux.vnet.ibm.com> Reply-To: Srikar Dronamraju References: <20140319152619.GB10406@linux.vnet.ibm.com> <20140319154705.GB8557@laptop.programming.kicks-ass.net> <20140319170829.GD8557@laptop.programming.kicks-ass.net> <20140320053350.GB30295@linux.vnet.ibm.com> <1395295019.2612.11.camel@buesod1.americas.hpqcorp.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1395295019.2612.11.camel@buesod1.americas.hpqcorp.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14032010-9574-0000-0000-00000C88AB55 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > This problem suggests that we missed a wakeup for a task that was adding > itself to the queue in a wait path. And the only place that can happen > is with the hb spinlock check for any pending waiters. Just in case we > missed some assumption about checking the hash bucket spinlock as a way > of detecting any waiters (powerpc?), could you revert this commit and > try the original atomic operations variant: > > https://lkml.org/lkml/2013/12/19/630 I think the above url and the commit id that I reverted i.e git://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b0c29f79ecea0b6fbcefc999 are the same. Or am I missing something? -- Thanks and Regards Srikar Dronamraju