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 B931BCCFA05 for ; Thu, 6 Nov 2025 16:23:30 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EA83910E94A; Thu, 6 Nov 2025 16:23:29 +0000 (UTC) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by gabe.freedesktop.org (Postfix) with ESMTP id 387E210E94A for ; Thu, 6 Nov 2025 16:23:29 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 26CEB12FC; Thu, 6 Nov 2025 08:23:21 -0800 (PST) Received: from [10.57.72.2] (unknown [10.57.72.2]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 075243F66E; Thu, 6 Nov 2025 08:23:26 -0800 (PST) Message-ID: <08c03b0b-79dc-4b4b-9c4d-81d188bc8f92@arm.com> Date: Thu, 6 Nov 2025 16:23:24 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1 5/8] drm/panthor: Fix immediate ticking on a disabled tick To: Boris Brezillon , Liviu Dudau , =?UTF-8?Q?Adri=C3=A1n_Larumbe?= Cc: dri-devel@lists.freedesktop.org, Florent Tomasin , Heinrich Fink , kernel@collabora.com References: <20251106144656.1012274-1-boris.brezillon@collabora.com> <20251106144656.1012274-6-boris.brezillon@collabora.com> From: Steven Price Content-Language: en-GB In-Reply-To: <20251106144656.1012274-6-boris.brezillon@collabora.com> Content-Type: text/plain; charset=UTF-8 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On 06/11/2025 14:46, Boris Brezillon wrote: > We have a few path where we schedule the tick work immediately without NIT: s/path/paths/> changing the resched_target. If the tick was stopped, this would lead > to a remaining_jiffies that's always > 0, and it wouldn't force a full > tick in that case. Add extra checks to cover that case properly. > > Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block") > Signed-off-by: Boris Brezillon > --- > drivers/gpu/drm/panthor/panthor_sched.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c > index b6489e9ba1f0..1eba56e7360d 100644 > --- a/drivers/gpu/drm/panthor/panthor_sched.c > +++ b/drivers/gpu/drm/panthor/panthor_sched.c > @@ -2358,8 +2358,12 @@ static void tick_work(struct work_struct *work) > if (drm_WARN_ON(&ptdev->base, ret)) > goto out_dev_exit; > > - if (time_before64(now, sched->resched_target)) > + if (sched->resched_target != U64_MAX && > + time_before64(now, sched->resched_target)) > remaining_jiffies = sched->resched_target - now; > + else if (sched->resched_target == U64_MAX && > + time_before64(now, sched->last_tick + sched->tick_period)) > + remaining_jiffies = sched->last_tick + sched->tick_period - now; I'm wondering if this would be cleaner with an extra variable (and a comment): u64 resched_target = sched->resched_target; /* If the tick is stopped, calculate when the next tick would be */ if (resched_target == U64_MAX) resched_target = sched->last_tick + sched->tick_period; if (time_before64(now, resched_target) remaining_jiffies = resched_target - now; It at least avoids some repetition. Thanks, Steve > > full_tick = remaining_jiffies == 0; >