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Message-ID: <20250825095056.GA87@bytedance> References: <20250806071848.GA629@bytedance> <20250806083810.27678-1-xupengbo@oppo.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250806083810.27678-1-xupengbo@oppo.com> Hi xupengbo, On Wed, Aug 06, 2025 at 04:38:10PM +0800, xupengbo wrote: ... ... > > It actually becomes: > if (cfs_rq->tg_load_avg_contrib > 0) > if cfs_rq->tg_load_avg_contrib == 0 , it will be false. As it is an unsigned > long, this condition is equivalent to : > if (cfs_rq->tg_load_avg_contrib) I suppose we have reached a conclusion that the right fix is to add a check of cfs_rq->tg_load_avg_contrib in cfs_rq_is_decayed()? Something like below: diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index af33d107d8034..3ebcb683063f0 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4056,6 +4056,9 @@ static inline bool cfs_rq_is_decayed(struct cfs_rq *cfs_rq) if (child_cfs_rq_on_list(cfs_rq)) return false; + if (cfs_rq->tg_load_avg_contrib) + return false; + return true; } If you also agree, can you send an updated patch to fix this problem? Thanks.