From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753583AbcICKxp (ORCPT ); Sat, 3 Sep 2016 06:53:45 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:34489 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752748AbcICKxo (ORCPT ); Sat, 3 Sep 2016 06:53:44 -0400 X-IBM-Helo: d06dlp03.portsmouth.uk.ibm.com X-IBM-MailFrom: heiko.carstens@de.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org;linux-s390@vger.kernel.org Date: Sat, 3 Sep 2016 12:53:34 +0200 From: Heiko Carstens To: Tejun Heo Cc: Bhaktipriya Shridhar , Martin Schwidefsky , Steffen Maier , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] s390: Remove deprecated create_singlethread_workqueue References: <20160830202720.GA31494@Karyakshetra> <20160831143110.GT12660@htj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160831143110.GT12660@htj.duckdns.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16090310-0016-0000-0000-0000022B34A7 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16090310-0017-0000-0000-000022DA3E95 Message-Id: <20160903105334.GA3917@osiris> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-09-03_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1609030158 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 31, 2016 at 10:31:10AM -0400, Tejun Heo wrote: > On Wed, Aug 31, 2016 at 01:57:20AM +0530, Bhaktipriya Shridhar wrote: > > The workqueue "appldata_wq" has been replaced with an ordered dedicated > > workqueue. > > > > WQ_MEM_RECLAIM has not been set since the workqueue is not being used on > > a memory reclaim path. > > > > The adapter->work_queue queues multiple work items viz > > &adapter->scan_work, &port->rport_work, &adapter->ns_up_work, > > &adapter->stat_work, adapter->work_queue, &adapter->events.work, > > &port->gid_pn_work, &port->test_link_work. Hence, an ordered > > dedicated workqueue has been used. > > > > WQ_MEM_RECLAIM has been set to ensure forward progress under memory > > pressure. > > I have no idea what these drivers do. s390 folks, can you please shed > some light on whether these workqueues can be depended on during > memory reclaim? The appldata device driver is only needed to gather statistical data and therefore my wait when memory reclaim is in progress. The zfcp device drivers is a SCSI-over-FC device driver and hence we depend on it during memory reclaim. So setting WQ_MEM_RECLAIM is the right thing to do here. The patch looks ok, and I applied it. Thanks!