From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH v3] drm/i915: Rework GPU reset sequence to match driver load & thaw Date: Tue, 26 Aug 2014 07:09:42 +0100 Message-ID: <20140826060942.GA2328@nuc-i3427.alporthouse.com> References: <8761ht7kiq.fsf@gaia.fi.intel.com> <1408125095-10699-1-git-send-email-alistair.mcaulay@intel.com> <20140820145826.GD12830@nuc-i3427.alporthouse.com> <2F6A3166A8653C4D914E172D478C0F012E4FF8A9@IRSMSX105.ger.corp.intel.com> <20140820155641.GF12830@nuc-i3427.alporthouse.com> <20140825201809.GI15520@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from fireflyinternet.com (mail.fireflyinternet.com [87.106.93.118]) by gabe.freedesktop.org (Postfix) with ESMTP id 609DB6E238 for ; Mon, 25 Aug 2014 23:09:48 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20140825201809.GI15520@phenom.ffwll.local> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Daniel Vetter Cc: "intel-gfx@lists.freedesktop.org" List-Id: intel-gfx@lists.freedesktop.org On Mon, Aug 25, 2014 at 10:18:09PM +0200, Daniel Vetter wrote: > On Wed, Aug 20, 2014 at 04:56:41PM +0100, Chris Wilson wrote: > > On Wed, Aug 20, 2014 at 03:21:55PM +0000, Mcaulay, Alistair wrote: > > > It is not the same. This is a special case when re-initialising the hw. This flag is to allow gem_init_hw() to complete successfully during reset. > > > At any other point during reset, -EAGAIN should be returned. > > > > Indeed. You've missed the point. Look closer at the reset counter and > > reset ordering. > > We could try to mark the gpu as reset again before starting the reinit to > avoid this kludge. But that has the problem that if the ring init fails we > have a bit a mess in marking the gpu terminally wedged. So I think overall > not prettier than what we have here ... And if I'm mistaken I guess I can > put on my idiot hat and merge the fixup ;-) See other patches during the week. Marking the reset as complete after performing the reset and before resuming the hardware is not ugly. If the reset fails, you still have the wedge | in-progress. If the reset succeeds but resume fails, you then have wedge | !in-progress. Seriously read the request patch to see how it straightens out ring access, full stop. -Chris -- Chris Wilson, Intel Open Source Technology Centre