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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 170E2C83F1A for ; Wed, 30 Aug 2023 18:45:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237268AbjH3ShW (ORCPT ); Wed, 30 Aug 2023 14:37:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245488AbjH3PT2 (ORCPT ); Wed, 30 Aug 2023 11:19:28 -0400 Received: from mout-p-101.mailbox.org (mout-p-101.mailbox.org [IPv6:2001:67c:2050:0:465::101]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE891E8 for ; Wed, 30 Aug 2023 08:19:24 -0700 (PDT) Received: from smtp1.mailbox.org (smtp1.mailbox.org [IPv6:2001:67c:2050:b231:465::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-101.mailbox.org (Postfix) with ESMTPS id 4RbSd40xTdz9sqG; Wed, 30 Aug 2023 17:19:20 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1693408760; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7WVr6sfDlpT+GcV4fVg5JZuFi7yMzbTGXcyHxed6FE0=; b=ECCXCyFcA0Z9AtLh4GVXYwvmh0ILfOF0IsPNnDYeXa865+ppe/T+TKmnEuo8rdavdc+GNl LJzvUM+lBrtuu//KNoH9/9U/xiDW9sVQb6HSZANVor5TTdI+HkD0HjGT7cxO79TfuQTvOJ PEAP6PMLX0Ur6mqXxD5dqaDuQa2jrD8JFIXPsZ9zk3Wo/TULizxhuBtt2DIIuYYdfFMeIk frPr+uxDZ7XVgOZ5NwPYxpQW5wEqLE9Fx68+vg4UMEBj/CaBHMGFEGBX/PdWGvVhxBFB9/ ZcMRNicBuEOcStC2hdLtJD4ykdiUO5kF9T+nJ6YCnT9IGC7gUML4098MfTcorA== Message-ID: <1f311318-aaf5-85fa-8f2c-dd0fafb8bfbb@mailbox.org> Date: Wed, 30 Aug 2023 17:19:17 +0200 MIME-Version: 1.0 Subject: Re: [PATCH v3 0/7] GPU workload hints for better performance Content-Language: de-CH-frami, en-CA To: "Lazar, Lijo" , "Yadav, Arvind" , "Koenig, Christian" , "Deucher, Alexander" , "Sharma, Shashank" , "Pan, Xinhui" , "airlied@gmail.com" , "daniel@ffwll.ch" , "Kuehling, Felix" , "amd-gfx@lists.freedesktop.org" Cc: "dri-devel@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" References: <20230828122614.3815122-1-Arvind.Yadav@amd.com> From: =?UTF-8?Q?Michel_D=c3=a4nzer?= In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-MBO-RS-ID: f95517fd879b3f33af4 X-MBO-RS-META: sajakrcg4hnowsbo5jugcgcqtuxus9uj Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/28/23 17:02, Lazar, Lijo wrote: > [AMD Official Use Only - General] > > > As mentioned with an older version of this series, this is an 'abuse' of power profile interface. > > This series is oversimplifying what PMFW algorithms are supposed to be doing. Whatever this series is doing, FW can do it better. > > To explain in simpler terms - it just tries to boost a profile based on ring type without even knowing how much of activity a job can trigger on a particular ring. A job scheduled to a GFX ring doesn't deserve a profile boost unless it can create a certain level of activity. In CPU terms, a job scheduled to a processor doesn't mean it deserves a frequency boost of that CPU.  At minimum it depends on more details like whether that job is compute bound or memory bound or memory bound.  > > While FW algorithms are designed to do that, this series tries to trivialise all such things. > > Unless you are able to show the tangible benefits in some terms like performance, power, or performance per watt,  I don't think this should be the default behaviour where driver tries to override FW just based on job submissions to rings. I know at least one tangible benefit this would have: a snappier GNOME desktop with lower input → output latency on many laptops. The bootup default profile doesn't work well for that IME. It should also help for issues like https://gitlab.freedesktop.org/drm/amd/-/issues/1500 . That said, I agree this approach is very aggressive. I think it might be acceptable with AC power, not sure about on battery though. (There might be better performance/power profile mechanisms to hook into than AC vs battery) -- Earthling Michel Dänzer | https://redhat.com Libre software enthusiast | Mesa and Xwayland developer