From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17EC8C432C0 for ; Fri, 29 Nov 2019 16:07:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DF5C62176D for ; Fri, 29 Nov 2019 16:07:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727131AbfK2QHi (ORCPT ); Fri, 29 Nov 2019 11:07:38 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:37572 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726909AbfK2QHi (ORCPT ); Fri, 29 Nov 2019 11:07:38 -0500 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 42FE5292AB2; Fri, 29 Nov 2019 16:07:37 +0000 (GMT) Date: Fri, 29 Nov 2019 17:07:34 +0100 From: Boris Brezillon To: Steven Price Cc: Rob Herring , Tomeu Vizoso , Alyssa Rosenzweig , stable@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH 8/8] drm/panfrost: Make sure the shrinker does not reclaim referenced BOs Message-ID: <20191129170734.50bb02ad@collabora.com> In-Reply-To: <64a6a09a-e83a-05be-8576-79a74f971286@arm.com> References: <20191129135908.2439529-1-boris.brezillon@collabora.com> <20191129135908.2439529-9-boris.brezillon@collabora.com> <64a6a09a-e83a-05be-8576-79a74f971286@arm.com> Organization: Collabora X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Fri, 29 Nov 2019 15:48:15 +0000 Steven Price wrote: > On 29/11/2019 13:59, Boris Brezillon wrote: > > Userspace might tag a BO purgeable while it's still referenced by GPU > > jobs. We need to make sure the shrinker does not purge such BOs until > > all jobs referencing it are finished. > > > > Fixes: 013b65101315 ("drm/panfrost: Add madvise and shrinker support") > > Cc: > > Signed-off-by: Boris Brezillon > > I'm happy with this, but I would also argue that it was previously user > space's job not to mark a BO purgeable while it's in use by the GPU. I was not aware of this design choice. > This is in some ways an ABI change so we should be sure this is > something that we want to support "forever" more. Well, in that case, the ABI change is bringing extra robustness, with AFAICT, no downside for those that were taking care of that in userspace. > But if Mesa has > 'always' been assuming this behaviour we might as well match. I think so, and VC4 seems to have the same expectations. > > Reviewed-by: Steven Price Thanks for the review.