From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?ISO-8859-1?Q?Christian_K=F6nig?= Subject: Re: [PATCH 12/13] drm/radeon: fix a bug with the ring syncing code Date: Tue, 24 Apr 2012 16:23:52 +0200 Message-ID: <4F96B778.5020608@vodafone.de> References: <1334875160-5454-1-git-send-email-deathsimple@vodafone.de> <1334875160-5454-13-git-send-email-deathsimple@vodafone.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1"; Format="flowed" Content-Transfer-Encoding: quoted-printable Return-path: Received: from outgoing.email.vodafone.de (outgoing.email.vodafone.de [139.7.28.128]) by gabe.freedesktop.org (Postfix) with ESMTP id 7EECC9E7D0 for ; Tue, 24 Apr 2012 07:23:56 -0700 (PDT) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org Errors-To: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org To: Dave Airlie Cc: dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org On 24.04.2012 16:04, Dave Airlie wrote: > 2012/4/19 Christian K=F6nig: >> Rings need to lock in order, otherwise >> the ring subsystem can deadlock. > No sure if its the commit or not but I was profiling on an r700 and > saw it create a semaphore for ring syncing. > > surely the r700 would have no need? > In theory the first hardware with more than a gfx ring was some r6xx = (but of course we haven't released any code/documentation for that yet), = so it's ok that the code generally checks for inter ring synchronization = needs on r7xx cards. But with the current mainline it should just boil down to an not taken = "if" branch, witch it currently doesn't (*crap*). Just tested with my = RV710 and I can confirm that it unnecessarily allocates a semaphore. = Another bug on my todo list for this patchset, going to send out an v2 = soon, but going to test it through first. Thanks for the comment, Christian.