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Mon, 24 Feb 2025 22:29:36 -0800 (PST) Message-ID: Date: Tue, 25 Feb 2025 14:29:29 +0800 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: Re: [PATCH 2/2] sched/fair: Fix premature check of WAKEUP_PREEMPTION To: Vincent Guittot Cc: Madadi Vineeth Reddy , Peter Zijlstra , Ingo Molnar , Juri Lelli , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Josh Don , Tianchen Ding , "open list:SCHEDULER" References: <20250221111226.64455-1-wuyun.abel@bytedance.com> <20250221111226.64455-3-wuyun.abel@bytedance.com> <6097164a-aa99-4869-b666-9dc7018c1f96@bytedance.com> <9d9d7432-9a5d-4216-ac53-a0f333a35d8f@bytedance.com> <83f8b833-af79-4d77-a179-5065aec994dc@bytedance.com> Content-Language: en-US From: Abel Wu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2/24/25 9:47 PM, Vincent Guittot wrote: > > Or we should just remove it. I'm curious to know who used it during > the last couple of years ? Having in mind that lazy preemption adds TBH I have never used this feature. But since Phil mentioned a case in debugging DELAY_DEQUEUE, I think we'd better keep it, what do you think? > another level as check_preempt_wakeup_fair() uses it so sched-idle > tasks might not always be immediately preempted anyway. Right, thanks for mention that. > > >> >> Thanks, >> Abel >>