From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH 7/7] Revert "drm/i915: Enable semaphores on BDW" Date: Fri, 8 Aug 2014 09:10:00 +0200 Message-ID: <20140808071000.GI8727@phenom.ffwll.local> References: <1407176119-5294-1-git-send-email-rodrigo.vivi@intel.com> <1407176119-5294-7-git-send-email-rodrigo.vivi@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-we0-f179.google.com (mail-we0-f179.google.com [74.125.82.179]) by gabe.freedesktop.org (Postfix) with ESMTP id 1132C6E809 for ; Fri, 8 Aug 2014 00:09:48 -0700 (PDT) Received: by mail-we0-f179.google.com with SMTP id u57so5214794wes.24 for ; Fri, 08 Aug 2014 00:09:48 -0700 (PDT) Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Rodrigo Vivi Cc: intel-gfx , Rodrigo Vivi List-Id: intel-gfx@lists.freedesktop.org On Thu, Aug 07, 2014 at 01:05:52PM -0700, Rodrigo Vivi wrote: > The rest of the series was a reference for the records of what I had and > let semaphores on bdw a bit more stable. But even with them we still get > hungs so please consider only to get the revert for now. Thanks for the reminder, picked up for -fixes, thanks for the patch. -Daniel > > > On Mon, Aug 4, 2014 at 11:15 AM, Rodrigo Vivi > wrote: > > > This reverts commit 521e62e49a42661a4ee0102644517dbe2f100a23. > > > > Although POST_SYNC brought a bit of stability to Semaphores on BDW > > it didn't solved all issues and some hungs can still occour when > > semaphores are enabled on BDW. Also some sloweness can be found on some > > igt tests, althoguth it apparently doesn't affect real workloads. > > > > Besides that, no real performance gain was found on our tests with > > different > > and even multiple workloads. > > > > Let's disable it again for now. At least until we are sure it is safe > > to re-enable it. > > > > Signed-off-by: Rodrigo Vivi > > --- > > drivers/gpu/drm/i915/i915_drv.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/gpu/drm/i915/i915_drv.c > > b/drivers/gpu/drm/i915/i915_drv.c > > index 6c4b25c..ec96f9a 100644 > > --- a/drivers/gpu/drm/i915/i915_drv.c > > +++ b/drivers/gpu/drm/i915/i915_drv.c > > @@ -481,6 +481,10 @@ bool i915_semaphore_is_enabled(struct drm_device *dev) > > if (i915.semaphores >= 0) > > return i915.semaphores; > > > > + /* Until we get further testing... */ > > + if (IS_GEN8(dev)) > > + return false; > > + > > #ifdef CONFIG_INTEL_IOMMU > > /* Enable semaphores on SNB when IO remapping is off */ > > if (INTEL_INFO(dev)->gen == 6 && intel_iommu_gfx_mapped) > > -- > > 1.9.3 > > > > _______________________________________________ > > Intel-gfx mailing list > > Intel-gfx@lists.freedesktop.org > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx > > > > > > -- > Rodrigo Vivi > Blog: http://blog.vivi.eng.br > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch