From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754587AbdCBIqH (ORCPT ); Thu, 2 Mar 2017 03:46:07 -0500 Received: from mail.free-electrons.com ([62.4.15.54]:33727 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754438AbdCBIqF (ORCPT ); Thu, 2 Mar 2017 03:46:05 -0500 Date: Thu, 2 Mar 2017 09:08:09 +0100 From: Boris Brezillon To: Eric Anholt Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2 RESEND] drm/vc4: Fulfill user BO creation requests from the kernel BO cache. Message-ID: <20170302090809.104c1dac@bbrezillon> In-Reply-To: <20170301185602.6873-1-eric@anholt.net> References: <20170301185602.6873-1-eric@anholt.net> X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 1 Mar 2017 10:56:01 -0800 Eric Anholt wrote: > The from_cache flag was actually "the BO is invisible to userspace", > so we can repurpose it to just zero out a cached BO and return it to > userspace. > > Improves wall time for a loop of 5 glsl-algebraic-add-add-1 by > -1.44989% +/- 0.862891% (n=28, 1 outlier removed from each that > appeared to be other system noise) > > Note that there's an intel-gpu-tools test to check for the proper > zeroing behavior here, which we continue to pass. > > Signed-off-by: Eric Anholt Reviewed-by: Boris Brezillon > --- > drivers/gpu/drm/vc4/vc4_bo.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/vc4/vc4_bo.c b/drivers/gpu/drm/vc4/vc4_bo.c > index 7abcd9c5dbe2..e5c7aa935b4b 100644 > --- a/drivers/gpu/drm/vc4/vc4_bo.c > +++ b/drivers/gpu/drm/vc4/vc4_bo.c > @@ -211,21 +211,22 @@ struct drm_gem_object *vc4_create_object(struct drm_device *dev, size_t size) > } > > struct vc4_bo *vc4_bo_create(struct drm_device *dev, size_t unaligned_size, > - bool from_cache) > + bool allow_unzeroed) > { > size_t size = roundup(unaligned_size, PAGE_SIZE); > struct vc4_dev *vc4 = to_vc4_dev(dev); > struct drm_gem_cma_object *cma_obj; > + struct vc4_bo *bo; > > if (size == 0) > return ERR_PTR(-EINVAL); > > /* First, try to get a vc4_bo from the kernel BO cache. */ > - if (from_cache) { > - struct vc4_bo *bo = vc4_bo_get_from_cache(dev, size); > - > - if (bo) > - return bo; > + bo = vc4_bo_get_from_cache(dev, size); > + if (bo) { > + if (!allow_unzeroed) > + memset(bo->base.vaddr, 0, bo->base.base.size); > + return bo; > } > > cma_obj = drm_gem_cma_create(dev, size);