Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756430Ab1DVRhC (ORCPT ); Fri, 22 Apr 2011 13:37:02 -0400 Received: from mail-qy0-f181.google.com ([209.85.216.181]:52282 "EHLO mail-qy0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756210Ab1DVRg7 convert rfc822-to-8bit (ORCPT ); Fri, 22 Apr 2011 13:36:59 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:reply-to:in-reply-to:references:date:message-id :subject:from:to:cc:content-type:content-transfer-encoding; b=tZkXSxWODJOT3AuQYlTCBiK4R20xKyJG2DNJQTzyhRlGPgUexv0ycuWGnoIR759Mmd /bb6kJ0HC5E98lkCAxOO6KPzU/FcIANJKl4wDWcH/mfSMdYZhnlSVgDxBNjJrVlwfuOb k0DU8D+iULjuaZbQm+KJcimoLB/QA5ZXJqTAc= MIME-Version: 1.0 Reply-To: sedat.dilek@gmail.com In-Reply-To: <20110422150222.GA2300@linux.vnet.ibm.com> References: <20110414224411.GF2141@linux.vnet.ibm.com> <20110421050823.GA4487@linux.vnet.ibm.com> <20110421142853.GA2235@linux.vnet.ibm.com> <20110422005046.GQ2235@linux.vnet.ibm.com> <20110422150222.GA2300@linux.vnet.ibm.com> Date: Fri, 22 Apr 2011 19:36:58 +0200 Message-ID: Subject: Re: linux-next: Tree for April 14 (Call-traces: RCU/ACPI/WQ related?) From: Sedat Dilek To: paulmck@linux.vnet.ibm.com Cc: Stephen Rothwell , linux-next@vger.kernel.org, LKML Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3216 Lines: 82 On Fri, Apr 22, 2011 at 5:02 PM, Paul E. McKenney wrote: > On Fri, Apr 22, 2011 at 11:40:54AM +0200, Sedat Dilek wrote: >> On Fri, Apr 22, 2011 at 2:50 AM, Paul E. McKenney >> wrote: >> > 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 >> > >> >> Here are the results of the Sedat's vote (European song contest :-)). > > ;-) > > Very strange.  RCU has told the per-CPU kthread that it needs to get > to work, but this kthread is still waiting from RCU's viewpoint. > Yet the "ps" command believes that this kthread is in fact runnable > at SCHED_FIFO priority 1. > > I can tell that this one will require some thought...  And more > diagnostics... > >                                                        Thanx, Paul > "We are with you in spirit." ( Level XX from Hybris shooter-game on Amiga (1989) ) - Sedat - -- 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/