From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932111AbcGBNoW (ORCPT ); Sat, 2 Jul 2016 09:44:22 -0400 Received: from mail-io0-f195.google.com ([209.85.223.195]:34023 "EHLO mail-io0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751574AbcGBNoV (ORCPT ); Sat, 2 Jul 2016 09:44:21 -0400 Date: Sat, 2 Jul 2016 09:44:17 -0400 From: Tejun Heo To: Bhaktipriya Shridhar Cc: Dave Airlie , David Airlie , Alex Deucher , Sinclair Yeh , Christian =?iso-8859-1?Q?K=F6nig?= , Daniel Vetter , Jonathon Jongsma , Jani Nikula , John Keeping , Ville =?iso-8859-1?Q?Syrj=E4l=E4?= , Noralf =?iso-8859-1?Q?Tr=F8nnes?= , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drm/qxl: Remove deprecated create_singlethread_workqueue Message-ID: <20160702134417.GA17431@htj.duckdns.org> References: <20160702110209.GA3560@Karyakshetra> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160702110209.GA3560@Karyakshetra> User-Agent: Mutt/1.6.1 (2016-04-27) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jul 02, 2016 at 04:32:09PM +0530, Bhaktipriya Shridhar wrote: > System workqueues have been able to handle high level of concurrency > for a long time now and there's no reason to use dedicated workqueues > just to gain concurrency. Since the workqueue in the QXL graphics device > driver is involved in freeing and processing the release ring > (workitem &qdev->gc_workqxl, maps to gc_work which calls > qxl_garbage_collect) and is not being used on a memory reclaim path, > dedicated gc_queue has been replaced with the use of system_wq. > > Unlike a dedicated per-cpu workqueue created with create_workqueue(), > system_wq allows multiple work items to overlap executions even on > the same CPU; however, a per-cpu workqueue doesn't have any CPU > locality or global ordering guarantees unless the target CPU is > explicitly specified and thus the increase of local concurrency > shouldn't make any difference. > > flush_work() has been called in qxl_device_fini() to ensure that there > are no pending tasks while disconnecting the driver. > > Signed-off-by: Bhaktipriya Shridhar Acked-by: Tejun Heo Thanks. -- tejun