From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yves-Alexis Perez Subject: Re: [Bug #12152] Huge wakeups number from i1915 Date: Mon, 08 Dec 2008 07:24:08 +0100 Message-ID: <1228717448.9677.3.camel@hidalgo> References: <6VnlupFpCsN.A.2rE.MsEPJB@chimera> <07Xes05z25M.A.VtF.ksEPJB@chimera> <20081207145203.0f998d5b@infradead.org> <200812072352.07151.rjw@sisk.pl> <20081207151203.46c01a0d@infradead.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-gfCYkbYSEa3tvhD/BZvV" Return-path: In-Reply-To: <20081207151203.46c01a0d-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org> Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: To: Arjan van de Ven Cc: "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List --=-gfCYkbYSEa3tvhD/BZvV Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On dim, 2008-12-07 at 15:12 -0800, Arjan van de Ven wrote: >=20 > > > at least in some of the cases where this has been seen the cause > is > > > the following: > > > The i915 DRM driver used to do polling for completion, busy > > > waiting. It moved to be interrupt driven, which is usually better > > > for power, but it will show up as more wakeups in powertop.... > >=20 > > IOW, this is not a regression? >=20 > I don't know about this specifc case (not enough information) but for > the case I described it's not a regression. Going to interrupt driven > from busy waiting is an improvement not a regression :) Well, several thousand or more interrupts really seems like a regression :). But it seems that's the same thing as the =E2=80=9CIRQ spinning=E2=80=9D (there was a thread on dri-devel about that). It seems fixed with a patch from Matthew Garrett applied to drm-intel/for-airlied but I don't think this has been applied to Linus master. Cheers, --=20 Yves-Alexis --=-gfCYkbYSEa3tvhD/BZvV Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAkk8vYEACgkQTUTAIMXAW64vDwCgh1LNVqPipycZnKo+/KVfU+Z0 aA0An1yBDT5SXJHCgc9uo/F+F3O8eJZZ =SR7r -----END PGP SIGNATURE----- --=-gfCYkbYSEa3tvhD/BZvV--