[PATCH v33 4/7] sched/proxy: Set TASK_RUNNING when shortcuting return migration

[John Stultz]

K Prateek's prior patch optimizing find_proxy_tasks() logic to
shortcut and run previously blocked tasks on the current cpu
made me realize while we are clearing the blocked_on and
is_blocked, we are not setting the task state as TASK_RUNNING
before returning the task to run.

So set the tasks to TASK_RUNNING prior to returning them to run.

Fixes: b049b81bdff6 ("sched: Handle blocked-waiter migration (and return migration)")
Signed-off-by: John Stultz <jstultz@xxxxxxxxxx>
---
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: K Prateek Nayak <kprateek.nayak@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
Cc: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Cc: Valentin Schneider <vschneid@xxxxxxxxxx>
Cc: Suleiman Souhlal <suleiman@xxxxxxxxxx>
Cc: Andrea Righi <arighi@xxxxxxxxxx>
Cc: Metin Kaya <Metin.Kaya@xxxxxxx>
Cc: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Zimuzo Ezeozue <zezeozue@xxxxxxxxxx>
Cc: Waiman Long <longman@xxxxxxxxxx>
Cc: Boqun Feng <boqun.feng@xxxxxxxxx>
Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxx>
Cc: Joel Fernandes <joelagnelf@xxxxxxxxxx>
Cc: Qais Yousef <qyousef@xxxxxxxxxxx>
Cc: Xuewen Yan <xuewen.yan94@xxxxxxxxx>
Cc: kuyo chang <kuyo.chang@xxxxxxxxxxxx>
Cc: hupu <hupu.gm@xxxxxxxxx>
Cc: Zhan Xusheng <zhanxusheng@xxxxxxxxxx>
Cc: zhidao su (Xiaomi) <soolaugust@xxxxxxxxx>
Cc: Hui Su <sh_def@xxxxxxx>
Cc: Shubhang Kaushik (Ampere) <sh@xxxxxxxxxx>
Cc: kernel-team@xxxxxxxxxxx
---
 kernel/sched/core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2cb42de255f7a..43ba76b5a3464 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7028,6 +7028,7 @@ find_proxy_task(struct rq *rq, struct task_struct *donor, struct rq_flags *rf)
 			clear_task_blocked_on(p, mutex);
 			if (task_current(rq, p) || p->wake_cpu == task_cpu(p)) {
 				p->is_blocked = 0;
+				WRITE_ONCE(p->__state, TASK_RUNNING);
 				return p;
 			}
 			goto activate;
@@ -7065,6 +7066,7 @@ find_proxy_task(struct rq *rq, struct task_struct *donor, struct rq_flags *rf)
 			__clear_task_blocked_on(p, NULL);
 			if (task_current(rq, p) || p->wake_cpu == task_cpu(p)) {
 				p->is_blocked = 0;
+				WRITE_ONCE(p->__state, TASK_RUNNING);
 				return p;
 			}
 			goto activate;
-- 
2.56.0.257.gf7497c7d27-goog