Commit cb90c8df authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'sched-urgent-2025-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull scheduler fix from Ingo Molnar:
 "Revert a scheduler performance optimization that regressed other
  workloads"

* tag 'sched-urgent-2025-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "sched/core: Reduce cost of sched_move_task when config autogroup"
parents b3ee1e46 76f970ce

kernel/sched/core.c

+3 −18
Original line number Diff line number Diff line
@@ -9016,7 +9016,7 @@ void sched_release_group(struct task_group *tg) 
	spin_unlock_irqrestore(&task_group_lock, flags);

}



static struct task_group *sched_get_task_group(struct task_struct *tsk)

static void sched_change_group(struct task_struct *tsk)

{

	struct task_group *tg;
@@ -9028,13 +9028,7 @@ static struct task_group *sched_get_task_group(struct task_struct *tsk) 
	tg = container_of(task_css_check(tsk, cpu_cgrp_id, true),

			  struct task_group, css);

	tg = autogroup_task_group(tsk, tg);



	return tg;

}



static void sched_change_group(struct task_struct *tsk, struct task_group *group)

{

	tsk->sched_task_group = group;

	tsk->sched_task_group = tg;



#ifdef CONFIG_FAIR_GROUP_SCHED

	if (tsk->sched_class->task_change_group)
@@ -9055,20 +9049,11 @@ void sched_move_task(struct task_struct *tsk, bool for_autogroup) 
{

	int queued, running, queue_flags =

		DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;

	struct task_group *group;

	struct rq *rq;



	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)

		return;



	update_rq_clock(rq);



	running = task_current_donor(rq, tsk);
@@ -9079,7 +9064,7 @@ void sched_move_task(struct task_struct *tsk, bool for_autogroup) 
	if (running)

		put_prev_task(rq, tsk);



	sched_change_group(tsk, group);

	sched_change_group(tsk);

	if (!for_autogroup)

		scx_cgroup_move_task(tsk);