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 91C51233718 for ; Wed, 16 Apr 2025 10:55:55 +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=1744800957; cv=none; b=hOlQhGwgHk4sX++p+FRocGuAVfiBvafFa/uSJXWsV1VoaSsz9I8nf9BinFVPSdcxlBagotXlNYGh2jDk+ukLzPffa8EiJ8JD2xA+EWHPO342XVGhtSjRouCFFjQHlmZVQW0Vja+Wxy8ZGI4Xbjgsi+LpWzb+78fIG6kYvqNVujw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744800957; c=relaxed/simple; bh=BX29mFmxNs7GRBvA+Nt3iMZeGvNwbVcTiCJ/uRpP9/E=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=hiRQP3pmuOa+53zfCth+3sF5M0NKlsmPyca+GKHnzhL2Ou3Sc5GT+PiT38f8TaolT0zgq75vRfoAr+k+Bvgd+dPNXlsumMmgfahjmLUkvWAijR8Z5zdcGIZdhiS6WI/Euv2ivyxCthryD/k00hiSoIGTJDVUN8+SSQKCT4ayyMQ= 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 AB693152B; Wed, 16 Apr 2025 03:55:52 -0700 (PDT) Received: from [192.168.178.115] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 053793F66E; Wed, 16 Apr 2025 03:55:51 -0700 (PDT) Message-ID: Date: Wed, 16 Apr 2025 12:55:44 +0200 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: Hongyan Xia , Xuewen Yan , 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> From: Dietmar Eggemann Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 14/04/2025 15:39, Hongyan Xia wrote: > 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); > > Tested this patch on several workloads and added util_est warnings. No > util_est overflow or underflow warnings were seen. > > Tested-by: Hongyan Xia Just to make sure, does this 'Tested-by' also apply to the current v2 version of this patch? https://lkml.kernel.org/r/20250325014733.18405-1-xuewen.yan@unisoc.com In this case Xuewen should apply it on his next version.