From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukas Hejtmanek Subject: Re: Possible wrong flushes on SNB Date: Wed, 12 Oct 2011 15:56:47 +0200 Message-ID: <20111012135647.GG22289@ics.muni.cz> References: <20111011121316.GJ14679@ics.muni.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: quoted-printable Return-path: Received: from minas.ics.muni.cz (minas.ics.muni.cz [147.251.4.40]) by gabe.freedesktop.org (Postfix) with ESMTP id A67F2A088B for ; Wed, 12 Oct 2011 06:57:32 -0700 (PDT) Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Chris Wilson Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org Chris, On Tue, Oct 11, 2011 at 09:01:20PM +0100, Chris Wilson wrote: > If you are using SNA, the likely cause of the flash is the flush, read, > modify, write of a fallback. That is we flush pending operations in the > batchbuffer (likely a fill to the scanout), read back from the scanout > the just modified region and perform the fallback with the CPU. That > modification is then queued up to be written out sometime in the near > future. That delay between the fill and the final write can cause > flickering. > = > By contrast UXA performs its fallbacks inplace and so such flicker > should not be any more perceivable than any other drawing operation. > = > File a bug. If you are using SNA, I'd like to prevent the fallback and > so avoid the flicker. Or I may have misdiagnosed it entirely, so in any > case I want sufficient information to reproduce. I did: #41718 = -- = Luk=E1=B9 Hejtm=E1nek