From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935886AbdJQOTU (ORCPT ); Tue, 17 Oct 2017 10:19:20 -0400 Received: from mail-qk0-f178.google.com ([209.85.220.178]:51563 "EHLO mail-qk0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935871AbdJQOTR (ORCPT ); Tue, 17 Oct 2017 10:19:17 -0400 X-Google-Smtp-Source: ABhQp+TLHYOl3GxnhmeydQQW2uCFvP0NWMJvtzf298NwVUv80pfoCl803RcQzVxprckcXFXqqCgnZA== Message-ID: <1508249953.19297.4.camel@ndufresne.ca> Subject: Re: [PATCH] media: vb2: unify calling of set_page_dirty_lock From: Nicolas Dufresne To: Sakari Ailus Cc: Stanimir Varbanov , Mauro Carvalho Chehab , Pawel Osciak , Marek Szyprowski , Kyungmin Park , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Date: Tue, 17 Oct 2017 10:19:13 -0400 In-Reply-To: <20171017101420.5a5cvyhkadmcqgfy@valkosipuli.retiisi.org.uk> References: <20170829112603.32732-1-stanimir.varbanov@linaro.org> <1507650010.2784.11.camel@ndufresne.ca> <20171015204014.2awhhygw6hi3lxas@valkosipuli.retiisi.org.uk> <1508108964.4502.6.camel@ndufresne.ca> <20171017101420.5a5cvyhkadmcqgfy@valkosipuli.retiisi.org.uk> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-JsLkc7swhun6acwfzwAf" X-Mailer: Evolution 3.24.6 (3.24.6-1.fc26) Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-JsLkc7swhun6acwfzwAf Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Le mardi 17 octobre 2017 =C3=A0 13:14 +0300, Sakari Ailus a =C3=A9crit : > On Sun, Oct 15, 2017 at 07:09:24PM -0400, Nicolas Dufresne wrote: > > Le dimanche 15 octobre 2017 =C3=A0 23:40 +0300, Sakari Ailus a =C3=A9cr= it : > > > Hi Nicolas, > > >=20 > > > On Tue, Oct 10, 2017 at 11:40:10AM -0400, Nicolas Dufresne wrote: > > > > Le mardi 29 ao=C3=BBt 2017 =C3=A0 14:26 +0300, Stanimir Varbanov a = =C3=A9crit : > > > > > Currently videobuf2-dma-sg checks for dma direction for > > > > > every single page and videobuf2-dc lacks any dma direction > > > > > checks and calls set_page_dirty_lock unconditionally. > > > > >=20 > > > > > Thus unify and align the invocations of set_page_dirty_lock > > > > > for videobuf2-dc, videobuf2-sg memory allocators with > > > > > videobuf2-vmalloc, i.e. the pattern used in vmalloc has been > > > > > copied to dc and dma-sg. > > > >=20 > > > > Just before we go too far in "doing like vmalloc", I would like to > > > > share this small video that display coherency issues when rendering > > > > vmalloc backed DMABuf over various KMS/DRM driver. I can reproduce > > > > this > > > > easily with Intel and MSM display drivers using UVC or Vivid as > > > > source. > > > >=20 > > > > The following is an HDMI capture of the following GStreamer > > > > pipeline > > > > running on Dragonboard 410c. > > > >=20 > > > > gst-launch-1.0 -v v4l2src device=3D/dev/video2 ! video/x- > > > > raw,format=3DNV16,width=3D1280,height=3D720 ! kmssink > > > > https://people.collabora.com/~nicolas/vmalloc-issue.mov > > > >=20 > > > > Feedback on this issue would be more then welcome. It's not clear > > > > to me > > > > who's bug is this (v4l2, drm or iommu). The software is unlikely to > > > > be > > > > blamed as this same pipeline works fine with non-vmalloc based > > > > sources. > > >=20 > > > Could you elaborate this a little bit more? Which Intel CPU do you > > > have > > > there? > >=20 > > I have tested with Skylake and Ivy Bridge and on Dragonboard 410c > > (Qualcomm APQ8016 SoC) (same visual artefact) >=20 > I presume kmssink draws on the display. Which GPU did you use? In order, GPU will be Iris Pro 580, Intel=C2=AE Ivybridge Mobile and an Adreno (3x ?). Why does it matter ? I'm pretty sure the GPU is not used on the DB410c for this use case. regards, Nicolas --=-JsLkc7swhun6acwfzwAf Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iF0EABECAB0WIQSScpfJiL+hb5vvd45xUwItrAaoHAUCWeYRYQAKCRBxUwItrAao HCu8AJ0SPGvrlZIu+P36chXlt/NH1Z12/gCfVl0RptQ1atVEfCJK3jeoxVGO23g= =sb/s -----END PGP SIGNATURE----- --=-JsLkc7swhun6acwfzwAf--