Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755370Ab1DVAvA (ORCPT ); Thu, 21 Apr 2011 20:51:00 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:46544 "EHLO e39.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751994Ab1DVAu6 (ORCPT ); Thu, 21 Apr 2011 20:50:58 -0400 Date: Thu, 21 Apr 2011 17:50:46 -0700 From: "Paul E. McKenney" To: sedat.dilek@gmail.com Cc: Stephen Rothwell , linux-next@vger.kernel.org, LKML Subject: Re: linux-next: Tree for April 14 (Call-traces: RCU/ACPI/WQ related?) Message-ID: <20110422005046.GQ2235@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20110414224411.GF2141@linux.vnet.ibm.com> <20110421050823.GA4487@linux.vnet.ibm.com> <20110421142853.GA2235@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="Kj7319i9nmIyA2yE" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4192 Lines: 93 --Kj7319i9nmIyA2yE Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit On Thu, Apr 21, 2011 at 04:47:31PM +0200, Sedat Dilek wrote: > On Thu, Apr 21, 2011 at 4:28 PM, Paul E. McKenney > wrote: > > On Thu, Apr 21, 2011 at 02:49:37PM +0200, Sedat Dilek wrote: > >> On Thu, Apr 21, 2011 at 12:24 PM, Sedat Dilek > >> wrote: [ . . . ] > >> Here the results from the 2nd-run (PREEMPT_RCU enabled). > > > > OK, and the grace periods clearly stopped advancing early on. > > > > Beyond that point, the per-CPU kthread is blocked, but RCU has some > > work for it to do. ?So someone has called invoke_rcu_cpu_kthread(), > > but rcu_cpu_kthread() is still blocked. ?I don't see a bug right > > off-hand, but it is early in the morning for me, so I might easily > > be missing something. > > > > Hmmm... > > > > The synchronization between these two assumes that the per-CPU > > kthread is always bound to the respective CPU, so if was somehow > > being migrated off, that might explain these results. > > > > I will add some more diagnostics, test them locally, then push > > out an update. ?Seem reasonable? > > > > And thank you again for the testing!!! > > Ping me when you have new stuff for testing. > Tomorrow (friday), here is public holiday and monday, too. > So a looong weekend. ;-) OK, I have a new sedat.2011.04.21a branch in the -rcu git tree: git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu.git This is against 2.6.39-rc3, as before. (Yes, I do need to rebase to 2.6.39-rc4, but didn't want to change any more than I had to.) I also have an updated script, which is attached. The output is similar to the earlier one, and it operated is pretty much the same way. Have a great weekend, and I look forward to seeing what shows up on this round. I confess to still being quite puzzled! Thanx, Paul --Kj7319i9nmIyA2yE Content-Type: application/x-sh Content-Description: collectdebugfs.sh Content-Disposition: attachment; filename="collectdebugfs.sh" Content-Transfer-Encoding: quoted-printable #!/bin/sh=0A#=0A# Collect RCU-related debugfs data. Set DEBUGFS_MP to the = debugfs=0A# mount point, defaults to /sys/kernel/debug.=0A#=0A# This progra= m is free software; you can redistribute it and/or modify=0A# it under the = terms of the GNU General Public License as published by=0A# the Free Softwa= re Foundation; either version 2 of the License, or=0A# (at your option) any= later version.=0A#=0A# This program is distributed in the hope that it wil= l be useful,=0A# but WITHOUT ANY WARRANTY; without even the implied warrant= y of=0A# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the=0A# = GNU General Public License for more details.=0A#=0A# You should have receiv= ed a copy of the GNU General Public License=0A# along with this program; if= not, write to the Free Software=0A# Foundation, Inc., 59 Temple Place - Su= ite 330, Boston, MA 02111-1307, USA.=0A#=0A# Copyright (C) IBM Corporation,= 2010=0A#=0A# Authors: Paul E. McKenney =0A=0AD= EBUGFS_MP=3D/sys/kernel/debug=0ADRCU=3D$DEBUGFS_MP/rcu=0A=0Awhile :=0Ado=0A= date=0A echo $DRCU/rcugp:=0A cat $DRCU/rcugp || echo no $DRCU/rcugp=0A ech= o $DRCU/rcuhier:=0A cat $DRCU/rcuhier || echo no $DRCU/rcuhier=0A echo $DRC= U/rcudata:=0A cat $DRCU/rcudata || echo no $DRCU/rcudata=0A echo $DRCU/rcu_= pending:=0A cat $DRCU/rcu_pending || echo no $DRCU/rcu_pending=0A echo $DRC= U/rcutorture:=0A cat $DRCU/rcutorture || echo no $DRCU/rcutorture=0A echo $= DRCU/rcuboost:=0A cat $DRCU/rcuboost || echo no $DRCU/rcuboost=0A ps -eo cl= ass,sched,rtprio,stat,state,sgi_p,cmd | grep '\[rcuc[0-9]'=0A ps -eo class,= sched,rtprio,stat,state,sgi_p,cmd | grep '\[rcun[0-9]'=0A ps -eo class,sche= d,rtprio,stat,state,sgi_p,cmd | grep '\[rcub[0-9]'=0A echo=0A sleep 15=0Ado= ne=0A --Kj7319i9nmIyA2yE-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/