Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751557AbcDOSkY (ORCPT ); Fri, 15 Apr 2016 14:40:24 -0400 Received: from mail-pa0-f51.google.com ([209.85.220.51]:36549 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750993AbcDOSkW (ORCPT ); Fri, 15 Apr 2016 14:40:22 -0400 Date: Fri, 15 Apr 2016 11:40:20 -0700 From: Gustavo Padovan To: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Daniel Stone , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Riley Andrews , Rob Clark , Greg Hackmann , John Harrison , laurent.pinchart@ideasonboard.com, seanpaul@google.com, marcheu@google.com, m.chehab@samsung.com, Maarten Lankhorst , Gustavo Padovan Subject: Re: [RFC 4/8] drm/fence: add in-fences support Message-ID: <20160415184020.GC23954@joana> Mail-Followup-To: Gustavo Padovan , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Daniel Stone , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Riley Andrews , Rob Clark , Greg Hackmann , John Harrison , laurent.pinchart@ideasonboard.com, seanpaul@google.com, marcheu@google.com, m.chehab@samsung.com, Maarten Lankhorst , Gustavo Padovan References: <1460683781-22535-1-git-send-email-gustavo@padovan.org> <1460683781-22535-5-git-send-email-gustavo@padovan.org> <20160415080538.GR2510@phenom.ffwll.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160415080538.GR2510@phenom.ffwll.local> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3877 Lines: 99 2016-04-15 Daniel Vetter : > On Thu, Apr 14, 2016 at 06:29:37PM -0700, Gustavo Padovan wrote: > > From: Gustavo Padovan > > > > There is now a new property called FENCE_FD attached to every plane > > state that receives the sync_file fd from userspace via the atomic commit > > IOCTL. > > > > The fd is then translated to a fence (that may be a fence_collection > > subclass or just a normal fence) and then used by DRM to fence_wait() for > > all fences in the sync_file to signal. So it only commits when all > > framebuffers are ready to scanout. > > > > Signed-off-by: Gustavo Padovan > > --- > > drivers/gpu/drm/Kconfig | 1 + > > drivers/gpu/drm/drm_atomic.c | 8 ++++++++ > > drivers/gpu/drm/drm_atomic_helper.c | 5 +++++ > > drivers/gpu/drm/drm_crtc.c | 7 +++++++ > > include/drm/drm_crtc.h | 1 + > > 5 files changed, 22 insertions(+) > > > > diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig > > index f2a74d0..3c987e3 100644 > > --- a/drivers/gpu/drm/Kconfig > > +++ b/drivers/gpu/drm/Kconfig > > @@ -12,6 +12,7 @@ menuconfig DRM > > select I2C > > select I2C_ALGOBIT > > select DMA_SHARED_BUFFER > > + select SYNC_FILE > > help > > Kernel-level support for the Direct Rendering Infrastructure (DRI) > > introduced in XFree86 4.0. If you say Y here, you need to select > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > > index 8ee1db8..6702502 100644 > > --- a/drivers/gpu/drm/drm_atomic.c > > +++ b/drivers/gpu/drm/drm_atomic.c > > @@ -30,6 +30,7 @@ > > #include > > #include > > #include > > +#include > > > > /** > > * drm_atomic_state_default_release - > > @@ -680,6 +681,11 @@ int drm_atomic_plane_set_property(struct drm_plane *plane, > > drm_atomic_set_fb_for_plane(state, fb); > > if (fb) > > drm_framebuffer_unreference(fb); > > + } else if (property == config->prop_fence_fd) { > > + state->fence = sync_file_fences_get(val); > > + if (!state->fence) > > + return -EINVAL; > > + fence_get(state->fence); > > Yeah, this fence_get must be part of sync_file_fences_get, this code here > has a race (exercise for the reader to describe where things go wrong > here). Also, you need to explicitly filter out -1 here first I think. Right, I missed this race. Move it sync_file_fences_get() just fixes it. I'll add the filter for -1 too and a testcase. > > Needs an atomic testcase to make sure setting FENCE_FD to -1 doesn't fall > over (since generic userspace might do this in an attempt to restore all > the state). > > > } else if (property == config->prop_crtc_id) { > > struct drm_crtc *crtc = drm_crtc_find(dev, val); > > return drm_atomic_set_crtc_for_plane(state, crtc); > > @@ -737,6 +743,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane, > > > > if (property == config->prop_fb_id) { > > *val = (state->fb) ? state->fb->base.id : 0; > > + } else if (property == config->prop_fence_fd) { > > + *val = -1; > > } else if (property == config->prop_crtc_id) { > > *val = (state->crtc) ? state->crtc->base.id : 0; > > } else if (property == config->prop_crtc_x) { > > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > > index f85ef8c..6ed8339 100644 > > --- a/drivers/gpu/drm/drm_atomic_helper.c > > +++ b/drivers/gpu/drm/drm_atomic_helper.c > > @@ -2687,6 +2687,11 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane *plane, > > { > > if (state->fb) > > drm_framebuffer_unreference(state->fb); > > + > > + if (state->fence) { > > + fence_put(state->fence); > > + state->fence = NULL; > > No need to set to NULL, we don't do that for ->fb either. Ok. Gustavo