sched_ext: Merge branch 'for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup into for-6.19

Pull cgroup/for-6.19 to receive:

 16dad7801aad ("cgroup: Rename cgroup lifecycle hooks to cgroup_task_*()")
 260fbcb92bbe ("cgroup: Move dying_tasks cleanup from cgroup_task_release() to cgroup_task_free()")
 d245698d727a ("cgroup: Defer task cgroup unlink until after the task is done switching out")

These are needed for the sched_ext cgroup exit ordering fix.

Signed-off-by: Tejun Heo <tj@kernel.org>

4 files changed, 22 insertions, 15 deletions

diff --git a/kernel/sched/autogroup.c b/kernel/sched/autogroup.c
index cdea931aae30..954137775f38 100644
--- a/kernel/sched/autogroup.c
+++ b/kernel/sched/autogroup.c
@@ -178,8 +178,8 @@ autogroup_move_group(struct task_struct *p, struct autogroup *ag)
 	 * this process can already run with task_group() == prev->tg or we can
 	 * race with cgroup code which can read autogroup = prev under rq->lock.
 	 * In the latter case for_each_thread() can not miss a migrating thread,
-	 * cpu_cgroup_attach() must not be possible after cgroup_exit() and it
-	 * can't be removed from thread list, we hold ->siglock.
+	 * cpu_cgroup_attach() must not be possible after cgroup_task_exit()
+	 * and it can't be removed from thread list, we hold ->siglock.
 	 *
 	 * If an exiting thread was already removed from thread list we rely on
 	 * sched_autogroup_exit_task().
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 096e8d03d85e..0324457622d7 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5151,6 +5151,8 @@ static struct rq *finish_task_switch(struct task_struct *prev)
 		if (prev->sched_class->task_dead)
 			prev->sched_class->task_dead(prev);
 
+		cgroup_task_dead(prev);
+
 		/* Task is done with its stack. */
 		put_task_stack(prev);
 
@@ -8474,10 +8476,12 @@ int sched_cpu_dying(unsigned int cpu)
 	sched_tick_stop(cpu);
 
 	rq_lock_irqsave(rq, &rf);
+	update_rq_clock(rq);
 	if (rq->nr_running != 1 || rq_has_pinned_tasks(rq)) {
 		WARN(true, "Dying CPU not properly vacated!");
 		dump_rq_tasks(rq, KERN_WARNING);
 	}
+	dl_server_stop(&rq->fair_server);
 	rq_unlock_irqrestore(rq, &rf);
 
 	calc_load_migrate(rq);
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 48357d4609bf..6b8a9286e2fc 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1582,6 +1582,9 @@ void dl_server_start(struct sched_dl_entity *dl_se)
 	if (!dl_server(dl_se) || dl_se->dl_server_active)
 		return;
 
+	if (WARN_ON_ONCE(!cpu_online(cpu_of(rq))))
+		return;
+
 	dl_se->dl_server_active = 1;
 	enqueue_dl_entity(dl_se, ENQUEUE_WAKEUP);
 	if (!dl_task(dl_se->rq->curr) || dl_entity_preempt(dl_se, &rq->curr->dl))
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 2554055c1ba1..b58e696d7ccc 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -8911,21 +8911,21 @@ simple:
 	return p;
 
 idle:
-	if (!rf)
-		return NULL;
-
-	new_tasks = sched_balance_newidle(rq, rf);
+	if (rf) {
+		new_tasks = sched_balance_newidle(rq, rf);
 
-	/*
-	 * Because sched_balance_newidle() releases (and re-acquires) rq->lock, it is
-	 * possible for any higher priority task to appear. In that case we
-	 * must re-start the pick_next_entity() loop.
-	 */
-	if (new_tasks < 0)
-		return RETRY_TASK;
+		/*
+		 * Because sched_balance_newidle() releases (and re-acquires)
+		 * rq->lock, it is possible for any higher priority task to
+		 * appear. In that case we must re-start the pick_next_entity()
+		 * loop.
+		 */
+		if (new_tasks < 0)
+			return RETRY_TASK;
 
-	if (new_tasks > 0)
-		goto again;
+		if (new_tasks > 0)
+			goto again;
+	}
 
 	/*
 	 * rq is about to be idle, check if we need to update the