From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?Q?Michel_D=c3=a4nzer?= Subject: Re: [PATCH] drm/radeon: Remove deprecated create_singlethread_workqueue Date: Thu, 7 Jul 2016 12:32:33 +0900 Message-ID: <85449fbd-45ba-7eea-8520-d0c19b8af001@daenzer.net> References: <20160702110350.GA3601@Karyakshetra> <20160702134614.GB17431@htj.duckdns.org> <9e69b1fd-eb93-1fee-15af-c905ee3a202f@daenzer.net> <20160705210644.GB25394@htj.duckdns.org> <936c5bae-b8e6-bf64-8be2-d27608814fac@daenzer.net> <20160706134532.GF3262@mtj.duckdns.org> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1818733821==" Return-path: Received: from mail.gna.ch (darkcity.gna.ch [195.226.6.51]) by gabe.freedesktop.org (Postfix) with ESMTP id 763136E714 for ; Thu, 7 Jul 2016 04:16:40 +0000 (UTC) In-Reply-To: <20160706134532.GF3262@mtj.duckdns.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Tejun Heo Cc: Alex Deucher , Bhaktipriya Shridhar , =?UTF-8?Q?Christian_K=c3=b6nig?= , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org List-Id: dri-devel@lists.freedesktop.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --===============1818733821== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="DlISLStch7J8rS84WoFGHRquTmRmXj91o" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --DlISLStch7J8rS84WoFGHRquTmRmXj91o Content-Type: multipart/mixed; boundary="sjWTdQX2kDOdSrBirC0W9PeV5taH4dXdX" From: =?UTF-8?Q?Michel_D=c3=a4nzer?= To: Tejun Heo Cc: Bhaktipriya Shridhar , Alex Deucher , =?UTF-8?Q?Christian_K=c3=b6nig?= , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Message-ID: <85449fbd-45ba-7eea-8520-d0c19b8af001@daenzer.net> Subject: Re: [PATCH] drm/radeon: Remove deprecated create_singlethread_workqueue References: <20160702110350.GA3601@Karyakshetra> <20160702134614.GB17431@htj.duckdns.org> <9e69b1fd-eb93-1fee-15af-c905ee3a202f@daenzer.net> <20160705210644.GB25394@htj.duckdns.org> <936c5bae-b8e6-bf64-8be2-d27608814fac@daenzer.net> <20160706134532.GF3262@mtj.duckdns.org> In-Reply-To: <20160706134532.GF3262@mtj.duckdns.org> --sjWTdQX2kDOdSrBirC0W9PeV5taH4dXdX Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 06.07.2016 22:45, Tejun Heo wrote: > On Wed, Jul 06, 2016 at 12:12:52PM +0900, Michel D=C3=A4nzer wrote: >=20 >> Not being very familiar with the workqueue APIs, I'll describe how it'= s >> supposed to work from a driver POV, which will hopefully help you guys= >> decide on the most appropriate alloc_workqueue parameters. >> >> There is one flip work queue for each hardware CRTC. At most one >> radeon_flip_work_func item can be queued for any of them at any time. >> When a radeon_flip_work_func item is queued, it should be executed ASA= P >> (so WQ_HIGHPRI might be appropriate?). >=20 > Hmmm... the only time WQ_HIGHPRI should be used is when it'd otherwise > require a kthread w/ nice value at -20. Would that be the case here? > What are the consequences of the work item getting delayed? A page flip may be delayed to a later display refresh cycle. > Also, what kind of delays matter here? Is it millisec range or micro? It can be the latter in theory, but normally rather the former. --=20 Earthling Michel D=C3=A4nzer | http://www.amd= =2Ecom Libre software enthusiast | Mesa and X developer --sjWTdQX2kDOdSrBirC0W9PeV5taH4dXdX-- --DlISLStch7J8rS84WoFGHRquTmRmXj91o Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEYEARECAAYFAld9zVEACgkQWoGvjmrbsgDrAQCfekwK1pjysczw5UFSVfhWjvWk WV8AnRSQm1M+QOBvbi1mNsmRh8eMEMs8 =O4ii -----END PGP SIGNATURE----- --DlISLStch7J8rS84WoFGHRquTmRmXj91o-- --===============1818733821== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZHJpLWRldmVs IG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlz dHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVsCg== --===============1818733821==--