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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=no 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 DC646C11F68 for ; Fri, 2 Jul 2021 14:09:28 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9063661103 for ; Fri, 2 Jul 2021 14:09:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9063661103 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1CCD089F6D; Fri, 2 Jul 2021 14:09:28 +0000 (UTC) Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5254B89F6D for ; Fri, 2 Jul 2021 14:09:26 +0000 (UTC) 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 B42861F44C5D; Fri, 2 Jul 2021 15:09:24 +0100 (BST) Date: Fri, 2 Jul 2021 16:09:21 +0200 From: Boris Brezillon To: Alyssa Rosenzweig Subject: Re: [PATCH v2 4/7] drm/panfrost: Add the ability to create submit queues Message-ID: <20210702160921.31fbe935@collabora.com> In-Reply-To: References: <20210701091224.3209803-1-boris.brezillon@collabora.com> <20210701091224.3209803-5-boris.brezillon@collabora.com> <20210702124320.1bd0f228@collabora.com> Organization: Collabora X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jason Ekstrand , Tomeu Vizoso , dri-devel@lists.freedesktop.org, Steven Price , Rob Herring , Alyssa Rosenzweig , Robin Murphy Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Fri, 2 Jul 2021 09:58:06 -0400 Alyssa Rosenzweig wrote: > > > My Vulkan knowledge is limited so I'm not sure whether this is the right > > > approach or not. In particular is it correct that an application can > > > create a high priority queue which could affect other (normal priority) > > > applications? > > > > That's what msm does (with no extra CAPS check AFAICT), and the > > freedreno driver can already create high priority queues if > > PIPE_CONTEXT_HIGH_PRIORITY is passed. Not saying that's okay to allow > > userspace to tweak the priority, but if that's a problem, other drivers > > are in trouble too ;-). > > Speaking of, how will PIPE_CONTEXT_HIGH_PRIORITY be implemented with the > new ioctl()? I envisioned something much simpler (for the old ioctl), > just adding a "high priority?" flag to the submit and internally > creating the two queues of normal/high priority for drm_sched to work > out. Is this juggling now moved to userspace? That's what freedreno does. I guess we could create 2 default queues (one normal and one high prio) and extend the old submit ioctl() to do what you suggest if you see a good reason to not switch to the new ioctl() directly. I mean, we'll have to keep support for both anyway, but switching to the new ioctl()) shouldn't be that hard (I can prepare a MR transitioning the gallium driver to BATCH_SUBMIT if you want).