[PATCH 0/7 v3] sched: reflect sched_entity move into task_group's load

[Vincent Guittot <vincent.guittot@linaro.org>]

Ensure that the move of a sched_entity will be reflected in load and
utilization of the task_group hierarchy.

When a sched_entity moves between groups or CPUs, load and utilization
of cfs_rq don't reflect the changes immediately but converge to new values.
As a result, the metrics are no more aligned with the new balance of the
load in the system and next decisions will have a biased view.

This patchset synchronizes load/utilization of sched_entity with its child
cfs_rq (se->my-q) only when tasks move to/from child cfs_rq:
-move between task group
-migration between CPUs
Otherwise, PELT is updated as usual.

Changes since v2:
- Propagate both utilization and load
- Synced sched_entity and se->my_q instead of adding the delta  

Changes since v1:
- This patch needs the patch that fixes issue with rq->leaf_cfs_rq_list
  "sched: fix hierarchical order in rq->leaf_cfs_rq_list" in order to work
  correctly. I haven't sent them as a single patchset because the fix is
  independent of this one
- Merge some functions that are always used together
- During update of blocked load, ensure that the sched_entity is synced
  with the cfs_rq applying changes
- Fix an issue when task changes its cpu affinity

Vincent Guittot (7):
  sched: factorize attach entity
  sched: fix hierarchical order in rq->leaf_cfs_rq_list
  sched: factorize PELT update
  sched: propagate load during synchronous attach/detach
  sched: propagate asynchrous detach
  sched: fix task group initialization
  sched: fix wrong utilization accounting when switching to fair class

 kernel/sched/core.c  |  21 ++--
 kernel/sched/fair.c  | 319 ++++++++++++++++++++++++++++++++++++++++-----------
 kernel/sched/sched.h |   2 +
 3 files changed, 264 insertions(+), 78 deletions(-)

-- 
1.9.1