[PATCH sched_ext/for-6.12] sched_ext: Don't trigger ops.quiescent/runnable() on migrations

[Tejun Heo]

A task moving across CPUs should not trigger quiescent/runnable task state
events as the task is staying runnable the whole time and just stopping and
then starting on different CPUs. Suppress quiescent/runnable task state
events if task_on_rq_migrating().

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Suggested-by: David Vernet <void@xxxxxxxxxxxxx>
Cc: Daniel Hodges <hodges.daniel.scott@xxxxxxxxx>
Cc: Changwoo Min <multics69@xxxxxxxxx>
Cc: Andrea Righi <andrea.righi@xxxxxxxxx>
Cc: Dan Schatzberg <schatzberg.dan@xxxxxxxxx>
---
 kernel/sched/ext.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -2050,7 +2050,7 @@ static void enqueue_task_scx(struct rq *
 	rq->scx.nr_running++;
 	add_nr_running(rq, 1);
 
-	if (SCX_HAS_OP(runnable))
+	if (SCX_HAS_OP(runnable) && !task_on_rq_migrating(p))
 		SCX_CALL_OP_TASK(SCX_KF_REST, runnable, p, enq_flags);
 
 	if (enq_flags & SCX_ENQ_WAKEUP)
@@ -2134,7 +2134,7 @@ static bool dequeue_task_scx(struct rq *
 		SCX_CALL_OP_TASK(SCX_KF_REST, stopping, p, false);
 	}
 
-	if (SCX_HAS_OP(quiescent))
+	if (SCX_HAS_OP(quiescent) && !task_on_rq_migrating(p))
 		SCX_CALL_OP_TASK(SCX_KF_REST, quiescent, p, deq_flags);
 
 	if (deq_flags & SCX_DEQ_SLEEP)