From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4DC38C4727F for ; Wed, 23 Sep 2020 11:32:04 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1260720C09 for ; Wed, 23 Sep 2020 11:32:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1260720C09 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D67276E0DA; Wed, 23 Sep 2020 11:31:58 +0000 (UTC) Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by gabe.freedesktop.org (Postfix) with ESMTPS id E846889D77; Wed, 23 Sep 2020 11:31:56 +0000 (UTC) Received: from xpredator (unknown [IPv6:2a02:2f08:4c14:a400:24d7:51ff:fed6:906d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: mvlad) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 6DDA22964A5; Wed, 23 Sep 2020 12:31:55 +0100 (BST) Date: Wed, 23 Sep 2020 14:31:52 +0300 From: Marius Vlad To: Daniel Vetter Message-ID: <20200923113152.GB8478@xpredator> References: <20180705101043.4883-1-daniel.vetter@ffwll.ch> <20180705102121.5091-1-daniel.vetter@ffwll.ch> <20200922133636.GA2369@xpredator> <20200923111443.GA8478@xpredator> MIME-Version: 1.0 In-Reply-To: Subject: Re: [Intel-gfx] [PATCH] drm: avoid spurious EBUSY due to nonblocking atomic modesets X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Intel Graphics Development , DRI Development , stable , Daniel Vetter , Pekka Paalanen Content-Type: multipart/mixed; boundary="===============1216797471==" Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" --===============1216797471== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="mojUlQ0s9EVzWg2t" Content-Disposition: inline --mojUlQ0s9EVzWg2t Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Sep 23, 2020 at 01:16:42PM +0200, Daniel Vetter wrote: > On Wed, Sep 23, 2020 at 1:14 PM Marius Vlad w= rote: > > > > On Wed, Sep 23, 2020 at 12:58:30PM +0200, Daniel Vetter wrote: > > > On Tue, Sep 22, 2020 at 3:36 PM Marius Vlad wrote: > > > > > > > > On Fri, Jan 31, 2020 at 07:34:00AM +0000, Daniel Stone wrote: > > > > > On Thu, 5 Jul 2018 at 11:21, Daniel Vetter wrote: > > > > > > When doing an atomic modeset with ALLOW_MODESET drivers are all= owed to > > > > > > pull in arbitrary other resources, including CRTCs (e.g. when > > > > > > reconfiguring global resources). > > > > > > > > > > > > But in nonblocking mode userspace has then no idea this happene= d, > > > > > > which can lead to spurious EBUSY calls, both: > > > > > > - when that other CRTC is currently busy doing a page_flip the > > > > > > ALLOW_MODESET commit can fail with an EBUSY > > > > > > - on the other CRTC a normal atomic flip can fail with EBUSY be= cause > > > > > > of the additional commit inserted by the kernel without users= pace's > > > > > > knowledge > > > > > > > > > > > > For blocking commits this isn't a problem, because everyone els= e will > > > > > > just block until all the CRTC are reconfigured. Only thing user= space > > > > > > can notice is the dropped frames without any reason for why fra= mes got > > > > > > dropped. > > > > > > > > > > > > Consensus is that we need new uapi to handle this properly, but= no one > > > > > > has any idea what exactly the new uapi should look like. As a s= top-gap > > > > > > plug this problem by demoting nonblocking commits which might c= ause > > > > > > issues by including CRTCs not in the original request to blocki= ng > > > > > > commits. > > > > Gentle ping. I've tried out Linus's master tree and, and like Pekka, > > > > I've noticed this isn't integrated/added. > > > > > > > > Noticed this is fixing (also) DPMS when multiple outputs are in use. > > > > Wondering if we can just use a _ONCE() variant instead of WARN_ON()= =2E I'm seeing > > > > the warning quite often. > > > > > > On which driver/chip does this happen? > > I've tried it out on i915. >=20 > lspci -nn please. Sure, $ lspci -nn 00:00.0 Host bridge [0600]: Intel Corporation Xeon E3-1200 v6/7th Gen Core = Processor Host Bridge/DRAM Registers [8086:5914] (rev 08) 00:02.0 VGA compatible controller [0300]: Intel Corporation UHD Graphics 62= 0 [8086:5917] (rev 07) 00:04.0 Signal processing controller [1180]: Intel Corporation Xeon E3-1200= v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem [8086:1903] (rev 08) 00:14.0 USB controller [0c03]: Intel Corporation Sunrise Point-LP USB 3.0 x= HCI Controller [8086:9d2f] (rev 21) 00:14.2 Signal processing controller [1180]: Intel Corporation Sunrise Poin= t-LP Thermal subsystem [8086:9d31] (rev 21) 00:15.0 Signal processing controller [1180]: Intel Corporation Sunrise Poin= t-LP Serial IO I2C Controller #0 [8086:9d60] (rev 21) 00:15.1 Signal processing controller [1180]: Intel Corporation Sunrise Poin= t-LP Serial IO I2C Controller #1 [8086:9d61] (rev 21) 00:16.0 Communication controller [0780]: Intel Corporation Sunrise Point-LP= CSME HECI #1 [8086:9d3a] (rev 21) 00:1c.0 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI Express R= oot Port #1 [8086:9d10] (rev f1) 00:1c.2 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI Express R= oot Port #3 [8086:9d12] (rev f1) 00:1c.4 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI Express R= oot Port #5 [8086:9d14] (rev f1) 00:1d.0 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI Express R= oot Port #9 [8086:9d18] (rev f1) 00:1f.0 ISA bridge [0601]: Intel Corporation Sunrise Point LPC Controller/e= SPI Controller [8086:9d4e] (rev 21) 00:1f.2 Memory controller [0580]: Intel Corporation Sunrise Point-LP PMC [8= 086:9d21] (rev 21) 00:1f.3 Audio device [0403]: Intel Corporation Sunrise Point-LP HD Audio [8= 086:9d71] (rev 21) 00:1f.4 SMBus [0c05]: Intel Corporation Sunrise Point-LP SMBus [8086:9d23] = (rev 21) 01:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS525A PC= I Express Card Reader [10ec:525a] (rev 01) 02:00.0 Network controller [0280]: Qualcomm Atheros QCA6174 802.11ac Wirele= ss Network Adapter [168c:003e] (rev 32) 6e:00.0 Non-Volatile memory controller [0108]: Toshiba Corporation Device [= 1179:0116] (it's a xps laptop) >=20 > Also adding Ville, who has an idea where this can all go wrong. The > one he pointed out thus far is gen12+ only though. > -Daniel >=20 > > > -Daniel > > > > > > > > > > > > > > > > > Thanks for writing this up Daniel, and for reminding me about it = some > > > > > time later as well ... > > > > > > > > > > Reviewed-by: Daniel Stone > > > > > > > > > > Cheers, > > > > > Daniel > > > > > _______________________________________________ > > > > > dri-devel mailing list > > > > > dri-devel@lists.freedesktop.org > > > > > https://lists.freedesktop.org/mailman/listinfo/dri-devel > > > > > > > > > > > > -- > > > Daniel Vetter > > > Software Engineer, Intel Corporation > > > http://blog.ffwll.ch >=20 >=20 >=20 > --=20 > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch --mojUlQ0s9EVzWg2t Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEcDKHej6x6uPk3J379jQS5glH1u8FAl9rMiQACgkQ9jQS5glH 1u+vJw//cder6Xw9NHtwbglN1tv7dva+dbXlzNuIf1hVgApnfIwYMtBFIDrrrVIu JQ8IH2MUeS66G5/eLSFgZHYJhL7ujj40mBud1feucGx2Ybfz3l357GSfI7wG8BkL Whct/cKeAZy8knQPsFlt0mip9CMs37OwHbkTBOu5K1SktVWUYg21Eye+76NmvG7s PlaIcftgC4gdfsW8Sma4BxM7XJU3E4igOu27HOaX1DwmsFEbblwC/SDltDQch+hM Do2G89xbpu0IuQSZ/IJqRnWCfzOsiwPgfm3Yt8ofeZDfmlb3RJsCidGGUUuIoGDW Rbl63vZkGtdNd9bjL0cHxdopag+e9Vjg//QaUgpAF2YScexdlYkJnLeJ2UFFU137 QZ6rDluB38sD7k1II5Cb8aMNUapwMi2AP4vBVkr7F7iLmWEgDxbTxvCqbJi4RMK7 iBAXyVJN5pqN6Kj0iaPnwUFVBSo7zWwOHUFKT4qNqN56GGX2/4pYtTdJA5+Ute/i MY+ALtXCxb0a2gleTQa5l9AjIbe3HbMfiDCpBl0wfzbnmS5OOd/xiDO4ZpEUB5G+ kVDVbXd+rEXvwgdqUUfPa6ag1wIdY2IMRs11PmP1FHAIvJA+Mvnzr1rBMe7M2xUG XtcqAc1Khqmg6x7h/Y1/KMSaQ2cIaRTvdHFmecd25hB2mj5rnHI= =sgFU -----END PGP SIGNATURE----- --mojUlQ0s9EVzWg2t-- --===============1216797471== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx --===============1216797471==--