[RFC PATCH 07/14] sched: compute load contribution by a group entity

[Paul Turner]

Unlike task entities who have a fixed weight, group entities instead own a
fraction of their parenting task_group's shares as their contributed weight.

Compute this fraction so that we can correctly account hierarchies and shared
entity nodes.

Signed-off-by: Paul Turner <pjt@xxxxxxxxxx>
Signed-off-by: Ben Segall <bsegall@xxxxxxxxxx>
---
 kernel/sched/fair.c |   29 +++++++++++++++++++++++------
 1 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 7771003..6d8af5e 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1096,17 +1096,34 @@ static inline u64 __synchronize_entity_decay(struct sched_entity *se)
 	return decays;
 }
 
+static inline void __update_task_entity_contrib(struct sched_entity *se)
+{
+	se->avg.load_avg_contrib = div64_u64(se->avg.runnable_avg_sum *
+					     se->load.weight,
+					     se->avg.runnable_avg_period + 1);
+}
+
+static inline void __update_group_entity_contrib(struct sched_entity *se)
+{
+	struct cfs_rq *cfs_rq = group_cfs_rq(se);
+	struct task_group *tg = cfs_rq->tg;
+
+	se->avg.load_avg_contrib = (cfs_rq->tg_load_contrib * tg->shares);
+	se->avg.load_avg_contrib /= atomic64_read(&tg->load_avg) + 1;
+}
+
 /* Compute the current contribution to load_avg by se, return any delta */
 static long __update_entity_load_avg_contrib(struct sched_entity *se)
 {
 	long old_contrib = se->avg.load_avg_contrib;
 
-	if (!entity_is_task(se))
-		return 0;
-
-	se->avg.load_avg_contrib = div64_u64(se->avg.runnable_avg_sum *
-					     se->load.weight,
-					     se->avg.runnable_avg_period + 1);
+	if (entity_is_task(se)) {
+		__update_task_entity_contrib(se);
+	} else {
+		if (!se->on_rq)
+			__synchronize_entity_decay(se);
+		__update_group_entity_contrib(se);
+	}
 
 	return se->avg.load_avg_contrib - old_contrib;
 }


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/