linux-kernel - [PATCH] sched: Combine ENQUEUE_MIGRATED check in activate

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Message-ID: <20250724121258.1826487-1-quic_zhonhan@quicinc.com>
Date: Thu, 24 Jul 2025 20:12:58 +0800
From: Zhongqiu Han <quic_zhonhan@...cinc.com>
To: <mingo@...hat.com>, <peterz@...radead.org>, <juri.lelli@...hat.com>,
        <vincent.guittot@...aro.org>, <dietmar.eggemann@....com>,
        <rostedt@...dmis.org>, <bsegall@...gle.com>, <mgorman@...e.de>,
        <vschneid@...hat.com>
CC: <linux-kernel@...r.kernel.org>, <quic_zhonhan@...cinc.com>
Subject: [PATCH] sched: Combine ENQUEUE_MIGRATED check in activate_task()

Combine the task_on_rq_migrating() check and the sched_mm_cid_migrate_to()
invocation into a single conditional block. This removes a redundant flag
check and slightly reduces the instruction count in a hot path.

Signed-off-by: Zhongqiu Han <quic_zhonhan@...cinc.com>
---
- This is a slight optimization and code cleanup, please let me know if you'd prefer to keep the current structure.
- Thanks

 kernel/sched/core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2343f5691c54..d6063cf503ee 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2118,10 +2118,10 @@ inline bool dequeue_task(struct rq *rq, struct task_struct *p, int flags)
 
 void activate_task(struct rq *rq, struct task_struct *p, int flags)
 {
-	if (task_on_rq_migrating(p))
+	if (task_on_rq_migrating(p)) {
 		flags |= ENQUEUE_MIGRATED;
-	if (flags & ENQUEUE_MIGRATED)
 		sched_mm_cid_migrate_to(rq, p);
+	}
 
 	enqueue_task(rq, p, flags);
 
-- 
2.43.0