From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id DA52F1FE470 for ; Fri, 14 Mar 2025 13:14:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741958079; cv=none; b=UFKM4Sw7JEENFt9StrttmvjDafadfBa5SzPvMGIBsy4ixxCYYlUfNnBIE5Bm80TO8BzmZqdSbCJzhKAEs7ezdDxzPQgXZXJgOH2iqa4YBDJnD5VzOdtJdfZke5xJadp+/tp3I72qp4HZ6U2Dgxt1dC1t5t0cM4L5Cvta4GURIO4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741958079; c=relaxed/simple; bh=LCOwegfYSlyPxTWUkilJBjC5KUTBoSn6ooShxFJ+aZo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=skrSawIRqmGrKQLXVvCAxkzKWSHGxGPhsjqyThCe5FQgw+4BwfaY1N7EICoyMHZa8Ulu6fgCK4Xc2mf7tH3mpHH857gF8plb1SC8F/oaylhAHZq1w2qMQ6adiN+EKeiyFVItS9ByPVivHEIH/uyVjpKuLRG+fGgIRhKkOYBzHtc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 40CF71424; Fri, 14 Mar 2025 06:14:47 -0700 (PDT) Received: from [10.57.40.41] (unknown [10.57.40.41]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1B3363F673; Fri, 14 Mar 2025 06:14:34 -0700 (PDT) Message-ID: <7dbd7dd3-dbf7-42e0-97c4-c5eb50250947@arm.com> Date: Fri, 14 Mar 2025 13:14:33 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH] sched/util_est: Do not sub the delayed-task's util-est To: Xuewen Yan , dietmar.eggemann@arm.com, vincent.guittot@linaro.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com Cc: rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.co, linux-kernel@vger.kernel.org, qyousef@layalina.io, ke.wang@unisoc.com, di.shen@unisoc.com, xuewen.yan94@gmail.com References: <20250314090909.8404-1-xuewen.yan@unisoc.com> Content-Language: en-US From: Hongyan Xia In-Reply-To: <20250314090909.8404-1-xuewen.yan@unisoc.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 14/03/2025 09:09, Xuewen Yan wrote: > In cpu_util_without, When the task is in rq, we should > sub the task's util_est, however, the delayed_task->on_rq > is true, however, the delayed_task's util had been sub > when sleep, so there is no need to sub the delayed task's > util-est. So add the checking of delayed-task. > > On the other hand, as said in [1], the logic of util_est's > enqueue/dequeue could be simplified. > So simplify it by aligning with the conditions of uclamp. > > [1]https://lore.kernel.org/all/CAB8ipk8pEvOtCm-d0o1rsekwxPWUHk9iBGtt9TLTWW-iWTQKiA@mail.gmail.com/ > > Signed-off-by: Xuewen Yan > --- > kernel/sched/fair.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index c798d2795243..bebf40a0fa4e 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -6930,7 +6930,7 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags) > * Let's add the task's estimated utilization to the cfs_rq's > * estimated utilization, before we update schedutil. > */ > - if (!(p->se.sched_delayed && (task_on_rq_migrating(p) || (flags & ENQUEUE_RESTORE)))) > + if (!p->se.sched_delayed || (flags & ENQUEUE_DELAYED)) > util_est_enqueue(&rq->cfs, p); > > if (flags & ENQUEUE_DELAYED) { > @@ -7168,7 +7168,7 @@ static int dequeue_entities(struct rq *rq, struct sched_entity *se, int flags) > */ > static bool dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) > { > - if (!(p->se.sched_delayed && (task_on_rq_migrating(p) || (flags & DEQUEUE_SAVE)))) > + if (!p->se.sched_delayed) > util_est_dequeue(&rq->cfs, p); > > util_est_update(&rq->cfs, p, flags & DEQUEUE_SLEEP); > @@ -8037,7 +8037,8 @@ cpu_util(int cpu, struct task_struct *p, int dst_cpu, int boost) > */ > if (dst_cpu == cpu) > util_est += _task_util_est(p); > - else if (p && unlikely(task_on_rq_queued(p) || current == p)) > + else if (p && unlikely(current == p || > + (task_on_rq_queued(p) && !p->se.sched_delayed))) > lsub_positive(&util_est, _task_util_est(p)); > > util = max(util, util_est); Have you tested the above changes to make sure util_est enqueue dequeue are balanced? util_est was broken for quite a while when merging delayed dequeue because now enqueue_ and dequeue_task() do not always appear in pairs. Since then, I always have a local patch like this (may be a bit out of date now) to make sure util_est is balanced https://lore.kernel.org/all/752ae417c02b9277ca3ec18893747c54dd5f277f.1724245193.git.hongyan.xia2@arm.com/