linux-kernel - [PATCH v3 19/57] sched: Simplify sched_move

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Message-ID: <20230612093538.871533689@infradead.org>
Date:   Mon, 12 Jun 2023 11:07:32 +0200
From:   Peter Zijlstra <peterz@...radead.org>
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Subject: [PATCH v3 19/57] sched: Simplify sched_move_task()

Use guards to reduce gotos and simplify control flow.

Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
---
 kernel/sched/core.c |   10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -10361,17 +10361,18 @@ void sched_move_task(struct task_struct
 	int queued, running, queue_flags =
 		DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;
 	struct task_group *group;
-	struct rq_flags rf;
 	struct rq *rq;
 
-	rq = task_rq_lock(tsk, &rf);
+	CLASS(task_rq_lock, rq_guard)(tsk);
+	rq = rq_guard.rq;
+
 	/*
 	 * Esp. with SCHED_AUTOGROUP enabled it is possible to get superfluous
 	 * group changes.
 	 */
 	group = sched_get_task_group(tsk);
 	if (group == tsk->sched_task_group)
-		goto unlock;
+		return;
 
 	update_rq_clock(rq);
 
@@ -10396,9 +10397,6 @@ void sched_move_task(struct task_struct
 		 */
 		resched_curr(rq);
 	}
-
-unlock:
-	task_rq_unlock(rq, tsk, &rf);
 }
 
 static inline struct task_group *css_tg(struct cgroup_subsys_state *css)