From mboxrd@z Thu Jan 1 00:00:00 1970 From: Damien Lespiau Subject: Re: [PATCH] drm/i915: Revert "drm/i915: Reject the pin ioctl on gen6+" Date: Fri, 19 Sep 2014 15:25:55 +0100 Message-ID: <20140919142555.GA19670@strange.ger.corp.intel.com> References: <1404371555-3760-1-git-send-email-damien.lespiau@intel.com> <20140707210455.GF17271@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id C68E16E674 for ; Fri, 19 Sep 2014 07:26:07 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20140707210455.GF17271@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: Daniel Vetter , intel-gfx@lists.freedesktop.org, Tomasz Madajczak List-Id: intel-gfx@lists.freedesktop.org Hi Daniel, On Mon, Jul 07, 2014 at 11:04:55PM +0200, Daniel Vetter wrote: > On Thu, Jul 03, 2014 at 08:12:35AM +0100, Damien Lespiau wrote: > > This reverts commit 02f6bcccf7c324115747aae2f0addd6af5d321cd. > > > > The OA buffer can contain global data (in particular, not linked to a > > context or a single batch execution) about GPU events (eg. hw context > > switches, rc6 transitions, frequency changes, ...) and needs to be > > mapped to GGTT. The pin ioctl provided a way to do that. > > > > Admittedly, this change broke what seems to be a valid use case of > > pinning a buffer in GGTT, even when PPGTT is used (which is the reason > > invoked in the commit message). > > Global OA buffers should be handled by the kernel and exposed through > perf, imo. I think I'll go lalala on this a bit longer ... Do you think that we can unblock this now that we have somewhat of path forward with Rob Bragg's work? I'm still uneasy with a precedent where we break working applications and it takes a long time for us to revert the offending change? Thanks! -- Damien