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[173.242.118.39]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2984dca17ffsm33035385ad.71.2025.11.12.06.21.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Nov 2025 06:21:28 -0800 (PST) From: Linwei Wang To: Aaron Lu Cc: Linwei Wang , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , linux-kernel@vger.kernel.org Subject: Re: [PATCH] sched/fair: remove redundant se initialization in unthrottle_cfs_rq Date: Wed, 12 Nov 2025 22:21:19 +0800 Message-Id: <20251112142119.375184-1-wanix1988@gmail.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Aaron, Your commit 956dfda6a708 removes the duplicate assignment after the early return, but still initializes 'se' at declaration: struct sched_entity *se = cfs_rq->tg->se[cpu_of(rq)]; This initialization happens before the early return check at line 6036-6037, so when runtime_remaining <= 0 causes an early return, the array access is wasted. My patch defers initialization until after the early return: - struct sched_entity *se = cfs_rq->tg->se[cpu_of(rq)]; + struct sched_entity *se; ... + se = cfs_rq->tg->se[cpu_of(rq)]; Your commit fixes the duplicate assignment; mine optimizes the early return path. They're independent optimizations. Should I rebase on top of 956dfda6a708? Thanks.