Migrating a delayed dequeued task doesn't help in balancing the number
of runnable tasks in the system.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
---
kernel/sched/fair.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index dc9725da033e..c34874203da2 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9394,11 +9394,15 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
/*
* We do not migrate tasks that are:
- * 1) throttled_lb_pair, or
- * 2) cannot be migrated to this CPU due to cpus_ptr, or
- * 3) running (obviously), or
- * 4) are cache-hot on their current CPU.
+ * 1) delayed dequeued unless we migrate load, or
+ * 2) throttled_lb_pair, or
+ * 3) cannot be migrated to this CPU due to cpus_ptr, or
+ * 4) running (obviously), or
+ * 5) are cache-hot on their current CPU.
*/
+ if ((p->se.sched_delayed) && (env->migration_type != migrate_load))
+ return 0;
+
if (throttled_lb_pair(task_group(p), env->src_cpu, env->dst_cpu))
return 0;
--
2.43.0