[RFC PATCH v2 22/25] sched/deadline: Make rt-cgroup's servers pull tasks on timer replenishment

[Yuri Andriaccio <yurand2000@gmail.com>]

From: luca abeni <luca.abeni@santannapisa.it>

Signed-off-by: luca abeni <luca.abeni@santannapisa.it>
Signed-off-by: Yuri Andriaccio <yurand2000@gmail.com>
---
 kernel/sched/deadline.c | 6 +++++-
 kernel/sched/rt.c       | 6 +++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index e263abcdc04..021d7349897 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1308,6 +1308,7 @@ static enum hrtimer_restart dl_server_timer(struct hrtimer *timer, struct sched_
 {
 	struct rq *rq = rq_of_dl_se(dl_se);
 	u64 fw;
+	bool has_tasks;
 
 	scoped_guard (rq_lock, rq) {
 		struct rq_flags *rf = &scope.rf;
@@ -1321,7 +1322,10 @@ static enum hrtimer_restart dl_server_timer(struct hrtimer *timer, struct sched_
 		if (!dl_se->dl_runtime)
 			return HRTIMER_NORESTART;
 
-		if (!dl_se->server_has_tasks(dl_se)) {
+		rq_unpin_lock(rq, rf);
+		has_tasks = dl_se->server_has_tasks(dl_se);
+		rq_repin_lock(rq, rf);
+		if (!has_tasks) {
 			replenish_dl_entity(dl_se);
 			dl_server_stopped(dl_se);
 			return HRTIMER_NORESTART;
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 677ab9e8aa4..116fa0422b9 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1,4 +1,3 @@
-#pragma GCC diagnostic ignored "-Wunused-function"
 // SPDX-License-Identifier: GPL-2.0
 /*
  * Real-Time Scheduling Class (mapped to the SCHED_FIFO and SCHED_RR
@@ -145,6 +144,11 @@ void init_tg_rt_entry(struct task_group *tg, struct rq *served_rq,
 
 static bool rt_server_has_tasks(struct sched_dl_entity *dl_se)
 {
+#ifdef CONFIG_SMP
+	struct rt_rq *rt_rq = &dl_se->my_q->rt;
+
+	group_pull_rt_task(rt_rq);
+#endif
 	return !!dl_se->my_q->rt.rt_nr_running;
 }
 
-- 
2.50.1