[COMMON] sched/{fair,rt}: copy sched avg data across switches between class

When switching a task between FAIR and RT, its sched avg data
has to be copied over, so that per-class PELT always works on
updated data.

Refer the I7561e16ceca2635a50f57e9361d351f22f991651

Change-Id: Id4f7c96c87c97441901b8dd8110ba2aed9ccf247
Signed-off-by: Johnlay Park <jonglae.park@samsung.com>

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 72cf9ee92a709809366013a96df10a4ee2ca73ce..0f71c8ef6385fbb6eae3b3d5edd6e1e2c2cfe5f7 100644 (file)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -11035,6 +11035,22 @@ static void attach_task_cfs_rq(struct task_struct *p)
                se->vruntime += cfs_rq->min_vruntime;
 }
 
+#ifdef CONFIG_SMP
+void copy_sched_avg(struct sched_avg *from, struct sched_avg *to, unsigned int ratio)
+{
+       if (ratio < 0)
+               ratio = 0;
+
+       to->last_update_time = from->last_update_time;
+       to->util_avg = (from->util_avg * ratio) / 100;
+       to->util_sum = (from->util_sum * ratio) / 100;
+       to->load_avg = (from->load_avg * ratio) / 100;
+       to->load_sum = (from->load_sum * ratio) / 100;
+}
+#else
+void copy_sched_avg(struct sched_avg *from, struct sched_avg *to, unsigned int ratio) { }
+#endif
+
 static void switched_from_fair(struct rq *rq, struct task_struct *p)
 {
        detach_task_cfs_rq(p);
@@ -11042,6 +11058,11 @@ static void switched_from_fair(struct rq *rq, struct task_struct *p)
 
 static void switched_to_fair(struct rq *rq, struct task_struct *p)
 {
+       /*
+        * Need to scale the applying ratio while migrating.
+        * - Copy rt sched avg into fair sched avg
+        */
+       copy_sched_avg(&p->rt.avg, &p->se.avg, 100);
        attach_task_cfs_rq(p);
 
        if (task_on_rq_queued(p)) {

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 17fb5acac3cd95705366fcfe285e4297652a5361..cc07931eb4a14e10064e259ddae0ec3512fdbde4 100644 (file)
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -2544,6 +2544,9 @@ void update_rt_load_avg(u64 now, struct sched_rt_entity *rt_se)
 }
 #endif /* CONFIG_SMP */
 
+extern void
+copy_sched_avg(struct sched_avg *from, struct sched_avg *to, unsigned int ratio);
+
 /*
  * When switching a task to RT, we may overload the runqueue
  * with RT tasks. In this case we try to push them off to
@@ -2551,6 +2554,8 @@ void update_rt_load_avg(u64 now, struct sched_rt_entity *rt_se)
  */
 static void switched_to_rt(struct rq *rq, struct task_struct *p)
 {
+       /* Copy fair sched avg into rt sched avg */
+       copy_sched_avg(&p->se.avg, &p->rt.avg, 100);
        /*
         * If we are already running, then there's nothing
         * that needs to be done. But if we are not running