From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932959AbaFDGuA (ORCPT ); Wed, 4 Jun 2014 02:50:00 -0400 Received: from casper.infradead.org ([85.118.1.10]:45049 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932747AbaFDGt4 (ORCPT ); Wed, 4 Jun 2014 02:49:56 -0400 Date: Wed, 4 Jun 2014 08:49:46 +0200 From: Peter Zijlstra To: Lai Jiangshan Cc: jjherne@linux.vnet.ibm.com, Sasha Levin , Tejun Heo , LKML , Dave Jones , Ingo Molnar , Thomas Gleixner , Steven Rostedt Subject: Re: workqueue: WARN at at kernel/workqueue.c:2176 Message-ID: <20140604064946.GF30445@twins.programming.kicks-ass.net> References: <53758B12.8060609@cn.fujitsu.com> <20140516115737.GP11096@twins.programming.kicks-ass.net> <20140516162945.GZ11096@twins.programming.kicks-ass.net> <53849EB7.9090302@linux.vnet.ibm.com> <20140527142637.GB19143@laptop.programming.kicks-ass.net> <53875F09.3090607@linux.vnet.ibm.com> <538DB076.4090704@cn.fujitsu.com> <20140603141659.GO30445@twins.programming.kicks-ass.net> <538E840D.2040300@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="2504uJlMzHih+KB5" Content-Disposition: inline In-Reply-To: <538E840D.2040300@cn.fujitsu.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --2504uJlMzHih+KB5 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Jun 04, 2014 at 10:27:25AM +0800, Lai Jiangshan wrote: > > Hmm, yes I think you're right. A queued wakeup can miss an affinity > > change like that. > >=20 > > Something like the below ought to cure that I suppose.. >=20 > As a non-scheduler developer, I can't find anything wrong with the patch > (I searched all on_rq in kernel/sched). You did fine finding that hole, so who knows, you might become one real soon now ;-) > but I think __migrate_task() is slow path comparing to sched_ttwu_pending= (). > So I prefer to change set_cpus_allowed_ptr() and __migrate_task() rather = than > to sched_ttwu_pending(). Yes, I agree, something there would be better, but I couldn't find anything without holes in. --2504uJlMzHih+KB5 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJTjsGKAAoJEHZH4aRLwOS6gDUQAIUXKx4afQOsdMh8+7RJiEBU 7wostf98eHEnoGm55l3pbP99SwD+VLqvvy5csUTxmZlhbjpB2iWmrpvKvTzITApv jUId+UN+9Fv2ycXK1201CykoClWeN/s2RsczkziZT1F9ZSfLoznaRFAzgvgmK/JX sbqhZSjY+/hvwF/W8rc5DqX+IuDPkVKIhrFx/TBXV+2BFJ+tsUdJuDT5C5E3b0cS 66wCyaiWEGlJaixhhDgfTovZewTSFTIighNeQSEJWW3upVk+zkuSt6+yYuIyazu7 KebVB7bFwEvkquqeCy4BZdR85LLZxafPLcCpuC5c5KrksXsHcAYdmXPlQsIqtMeq Wq/aWG5jA+U9gWKJSOVWyaEOb50Wl13BkIThoWQ5qT40Nm6HdXgpPhY/72EkFvpI UCF495gftXtq8NA6A+hgcovWmnFVIz4IvvJY76IPy6pCEDPPS/8HvynWDCRL5PlN U/byNI1WXvCgZ9Z2BrgDM57WZa7a0zDx+EZePuAleCgDPMdgo+/uvWc7Fm8h45ZE j/3hanF/nEA6He621bGZM4+xOTYCyi1ujAOnWkKm+1T72J7tvbzDckIaQU4VaQU2 UdB1TVLtpbwugfSd5VXXNRGVrkFuV5l8vQGPmOkQbAuPNFR+ssf857eGpAxBSvpM m4oHsHPJYrJnViy6DtOr =6EzU -----END PGP SIGNATURE----- --2504uJlMzHih+KB5--