From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751683Ab1EJTcX (ORCPT ); Tue, 10 May 2011 15:32:23 -0400 Received: from e2.ny.us.ibm.com ([32.97.182.142]:48407 "EHLO e2.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750704Ab1EJTcW (ORCPT ); Tue, 10 May 2011 15:32:22 -0400 Date: Tue, 10 May 2011 12:32:16 -0700 From: "Paul E. McKenney" To: Yinghai Lu Cc: Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: [GIT PULL rcu/next] rcu commits for 2.6.40 Message-ID: <20110510193216.GN2258@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20110508151848.GA21906@linux.vnet.ibm.com> <20110509073636.GA18247@elte.hu> <20110510085623.GG2258@linux.vnet.ibm.com> <4DC97E49.7040401@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DC97E49.7040401@kernel.org> 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 On Tue, May 10, 2011 at 11:04:57AM -0700, Yinghai Lu wrote: > On 05/10/2011 01:56 AM, Paul E. McKenney wrote: > > On Mon, May 09, 2011 at 02:09:21PM -0700, Yinghai Lu wrote: > >> On Mon, May 9, 2011 at 12:36 AM, Ingo Molnar wrote: > >>> > >>> * Paul E. McKenney wrote: > >>> > >>>> Hello, Ingo, > >>>> > >>>> This pull request covers RCU chnages for 2.6.40. The major new features > >>>> are RCU priority boosting and the addition of kfree_rcu(), the latter > >>>> courtesy of Lai Jiangshan. These two features cover well over half > >>>> of the commits. There are a number of smaller features and bug fixes. > >>>> All have been sent to LKML in the following batches: > >>>> > >>>> 0. https://lkml.org/lkml/2011/2/22/660: RCU priority boosting preview > >>>> 1. https://lkml.org/lkml/2011/5/1/19: RCU priority boosting, kfree_rcu() > >>>> 2. https://lkml.org/lkml/2011/5/2/40: More uses of kfree_rcu() > >>>> 3. https://lkml.org/lkml/2011/5/8/60: miscellaneous > >>>> > >>>> The kfree_rcu() uses in the pull request have Acked-by:s from the > >>>> maintainers. I have some additional kfree_rcu() requests that lack > >>>> Acked-by:s, and I will deal with these later. > >>>> > >>>> These channges are available in the -rcu git repository at: > >>>> > >>>> git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu.git rcu/next > >>> > >>> Pulled, thanks a lot Paul! > >>> > >> > >> it seems with this one in tip, my 8 sockets test setup will report cpu stall. > >> > >> after hard code to enable rcu_cpu_stall_suppress > >> > >> Index: linux-2.6/kernel/rcutree.c > >> =================================================================== > >> --- linux-2.6.orig/kernel/rcutree.c > >> +++ linux-2.6/kernel/rcutree.c > >> @@ -174,7 +174,7 @@ module_param(blimit, int, 0); > >> module_param(qhimark, int, 0); > >> module_param(qlowmark, int, 0); > >> > >> -int rcu_cpu_stall_suppress __read_mostly; > >> +int rcu_cpu_stall_suppress __read_mostly = 1; > >> module_param(rcu_cpu_stall_suppress, int, 0644); > >> > >> static void force_quiescent_state(struct rcu_state *rsp, int relaxed); > >> > >> will get system hang after pnp ACPI init. > > > > Could you please send the stack traces from the RCU CPU stall? Also, > > you do have ce31332d3c77532d6ea97ddcb475a2b02dd358b4 applied, correct? > > > > Thanx, Paul > > Do not have time to bisect it at this point. Could you please send the stack traces from the RCU CPU stall? Thanx, Paul > can you prepare clean revert patch for following commit to test? > > commit a00e0d714fbded07a7a2254391ce9ed5a5cb9d82 > Author: Paul E. McKenney > Date: Tue Feb 8 17:14:39 2011 -0800 > > rcu: Remove conditional compilation for RCU CPU stall warnings > > > Thanks > > Yinghai Lu