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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id AB10AEB64DA for ; Tue, 4 Jul 2023 09:25:45 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0B7A010E2D2; Tue, 4 Jul 2023 09:25:45 +0000 (UTC) Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id CBA2510E2C2 for ; Tue, 4 Jul 2023 09:25:42 +0000 (UTC) Date: Tue, 4 Jul 2023 11:25:32 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1688462736; 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: in-reply-to:in-reply-to:references:references; bh=qPnlV1qPV+FX8QsFJRDWzuCP7fOxJePUcEoo+JgtoPs=; b=lp21xsRQj2oKCzfdJmcUc1FSy0uY8z3gLG3hShsOf0roe3BWiQj/kve1KTUWYkIrpYCcYK QwOQ89UXgt50/CmoD6I8JHKvE2nbhohfT5PniziHjyf2HhpZb12YDkIOApgfIMiODJYutR 20dJ2ps8Rt8658KiH/XcjtQGDyJeg1SIMN3hgCaBUWc07HChNPXOwunr+9jUVqsYCzN/sj d9cmKy6iS6DL5z3zRv07L34FnFS5n0Vzk1qOTIZBrvlNguBZkMsY/3LQOY6LdrumnhZT6O 9AUsSZh5n3a91hknIVbLJB8ARleXzGmjU+up3QXv4uAvSkJzJRfsEGWQKyPxYA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1688462736; 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: in-reply-to:in-reply-to:references:references; bh=qPnlV1qPV+FX8QsFJRDWzuCP7fOxJePUcEoo+JgtoPs=; b=aMWtnbWJe0xZRfzZFBVo+Yz/KKBAFcoweeZhIKJWwU+3Hj+G7uK8qfv6gktPaluvIOvK90 ZXKoVqzOg9RFcUBQ== From: Sebastian Andrzej Siewior To: Tvrtko Ursulin Message-ID: <20230704092532.k-Fi14oC@linutronix.de> References: <20230630130949.coN0sVU4@linutronix.de> <5af9b5cb-2342-8de3-07f2-86f2be6201eb@linux.intel.com> <20230703161256.21Qmrm9d@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Subject: Re: [Intel-gfx] [RFC] tentative fix for drm/i915/gt regression on preempt-rt X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-rt-users@vger.kernel.org, intel-gfx@lists.freedesktop.org, Chris Wilson , Paul Gortmaker , Rodrigo Vivi , Thomas Gleixner Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 2023-07-04 09:02:07 [+0100], Tvrtko Ursulin wrote: > Lets make it a two patch series and then see. First patch to see if we can > really get away without the top level preempt_disable, and then second patch > to see if we can get away with preemptible short sleeps too. oki. > I guess on RT the top priority is consistent scheduling latency and not so > much potential UI latency in some edge cases? Saying that because if waiting I would says, yes. If you do RT and you provide some kind of GUI then you prefer to meet your deadlines for your RT load over some UI latency. > on the hw reset is made preemptible, _in theory_ it can prolong the reset > completion (as observed by i915), and so result in more UI glitching than it > normally would. Could be a theoretical point only because it requires both > CPU over-subscribe and GPU hangs. It could also easily be that the reset > path is only one path, and not so interesting one even, which can cause this > on RT. I see. > Regards, > > Tvrtko Sebastian