Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753283AbcD1RnT (ORCPT ); Thu, 28 Apr 2016 13:43:19 -0400 Received: from mail-oi0-f50.google.com ([209.85.218.50]:32852 "EHLO mail-oi0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752194AbcD1RnR convert rfc822-to-8bit (ORCPT ); Thu, 28 Apr 2016 13:43:17 -0400 MIME-Version: 1.0 X-Originating-IP: [2a02:168:56b5:0:ac27:b86c:7764:9429] In-Reply-To: <20160428165619.GD4329@intel.com> References: <20160426143635.GW8291@phenom.ffwll.local> <20160426162621.GU4329@intel.com> <20160426172049.GB2558@phenom.ffwll.local> <20160426174045.GC4329@intel.com> <20160426182346.GC2558@phenom.ffwll.local> <20160426185506.GH4329@intel.com> <20160426200505.GD2558@phenom.ffwll.local> <571FD402.6050407@google.com> <20160428143644.GA3496@joana> <20160428165619.GD4329@intel.com> Date: Thu, 28 Apr 2016 19:43:16 +0200 X-Google-Sender-Auth: lEN1DBLbaQht0md7DuAEPQfqdC8 Message-ID: Subject: Re: [RFC v2 5/8] drm/fence: add in-fences support From: Daniel Vetter To: =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= Cc: Gustavo Padovan , Daniel Stone , Greg Hackmann , Gustavo Padovan , Daniel Stone , Riley Andrews , dri-devel , Linux Kernel Mailing List , =?UTF-8?B?QXJ2ZSBIasO4bm5ldsOlZw==?= , John Harrison 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: 883 Lines: 20 On Thu, Apr 28, 2016 at 6:56 PM, Ville Syrjälä wrote: >> - better for tracing, can identify the buffer/fence promptly > > Can fences be reused somehow while still attached to a plane, or ever? > That might cause some oddness if you, say, leave a fence attached to one > plane and then do a modeset on another crtc perhaps which needs to turn > the first crtc off+on to reconfigure something. Fences auto-disappear of course and don't stick around when you duplicate the drm_plane_state again. I still don't really get the real concerns though ... In the end it's purely a transport question, and both ABI ideas work out semantically exactly the same in the end. It's just that at least in my opinion FENCE_FD prop is a lot more convenient. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch