sched: Fix bug in SCHED_IDLE interaction with group scheduling
One of the isolation modifications for SCHED_IDLE is the
unitization of sleeper credit. However the check for this
assumes that the sched_entity we're placing always belongs to a
task.
This is potentially not true with group scheduling and leaves
us rummaging randomly when we try to pull the policy.
Signed-off-by: Paul Turner <pjt@google.com>
Cc: peterz@infradead.org
LKML-Reference: <alpine.DEB.1.00.0907101649570.29914@kitami.corp.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index ba7fd6e..7c248dc 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -687,7 +687,8 @@
* all of which have the same weight.
*/
if (sched_feat(NORMALIZED_SLEEPER) &&
- task_of(se)->policy != SCHED_IDLE)
+ (!entity_is_task(se) ||
+ task_of(se)->policy != SCHED_IDLE))
thresh = calc_delta_fair(thresh, se);
vruntime -= thresh;