[PATCH v2] sched_ext: switch class when preempted by higher priority scheduler

[Honglei Wang <jameshongleiwang@126.com>]

ops.cpu_release() function, if defined, must be invoked when preempted by
a higher priority scheduler class task. This scenario was skipped in
commit f422316d7466 ("sched_ext: Remove switch_class_scx()"). Let's fix
it.

Fixes: f422316d7466 ("sched_ext: Remove switch_class_scx()")
Signed-off-by: Honglei Wang <jameshongleiwang@126.com>
---
 kernel/sched/ext.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index 19d2699cf638..ef0e3f2c1e6f 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -3034,7 +3034,7 @@ static void put_prev_task_scx(struct rq *rq, struct task_struct *p,
 		 */
 		if (p->scx.slice && !scx_rq_bypassing(rq)) {
 			dispatch_enqueue(&rq->scx.local_dsq, p, SCX_ENQ_HEAD);
-			return;
+			goto switch_class;
 		}
 
 		/*
@@ -3051,6 +3051,7 @@ static void put_prev_task_scx(struct rq *rq, struct task_struct *p,
 		}
 	}
 
+switch_class:
 	if (next && next->sched_class != &ext_sched_class)
 		switch_class(rq, next);
 }
-- 
2.45.2