sched: track cfs_rq->curr on !group-scheduling too

Noticed by Roman Zippel: use cfs_rq->curr in the !group-scheduling
case too. Small micro-optimization and cleanup effect:

   text    data     bss     dec     hex filename
   36269    3482      24   39775    9b5f sched.o.before
   36177    3486      24   39687    9b07 sched.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 10 insertions, 23 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index f6a81061fd50..3209e2cc2c2e 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -189,11 +189,11 @@ struct cfs_rq {
         struct rb_root tasks_timeline;
         struct rb_node *rb_leftmost;
         struct rb_node *rb_load_balance_curr;
-#ifdef CONFIG_FAIR_GROUP_SCHED
         /* 'curr' points to currently running entity on this cfs_rq.
          * It is set to NULL otherwise (i.e when none are currently running).
          */
         struct sched_entity *curr;
+#ifdef CONFIG_FAIR_GROUP_SCHED
         struct rq *rq;  /* cpu runqueue to which this cfs_rq is attached */
 
         /* leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 105d57b41aa2..335faf06a561 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -111,51 +111,38 @@ extern struct sched_class fair_sched_class;
  * CFS operations on generic schedulable entities:
  */
 
-#ifdef CONFIG_FAIR_GROUP_SCHED
-
-/* cpu runqueue to which this cfs_rq is attached */
-static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
-{
-        return cfs_rq->rq;
-}
-
 /* currently running entity (if any) on this cfs_rq */
 static inline struct sched_entity *cfs_rq_curr(struct cfs_rq *cfs_rq)
 {
         return cfs_rq->curr;
 }
 
-/* An entity is a task if it doesn't "own" a runqueue */
-#define entity_is_task(se)      (!se->my_q)
-
 static inline void
 set_cfs_rq_curr(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
         cfs_rq->curr = se;
 }
 
-#else   /* CONFIG_FAIR_GROUP_SCHED */
+#ifdef CONFIG_FAIR_GROUP_SCHED
 
+/* cpu runqueue to which this cfs_rq is attached */
 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
 {
-        return container_of(cfs_rq, struct rq, cfs);
+        return cfs_rq->rq;
 }
 
-static inline struct sched_entity *cfs_rq_curr(struct cfs_rq *cfs_rq)
-{
-        struct rq *rq = rq_of(cfs_rq);
+/* An entity is a task if it doesn't "own" a runqueue */
+#define entity_is_task(se)      (!se->my_q)
 
-        if (unlikely(rq->curr->sched_class != &fair_sched_class))
-                return NULL;
+#else   /* CONFIG_FAIR_GROUP_SCHED */
 
-        return &rq->curr->se;
+static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
+{
+        return container_of(cfs_rq, struct rq, cfs);
 }
 
 #define entity_is_task(se)      1
 
-static inline void
-set_cfs_rq_curr(struct cfs_rq *cfs_rq, struct sched_entity *se) { }
-
 #endif  /* CONFIG_FAIR_GROUP_SCHED */
 
 static inline struct task_struct *task_of(struct sched_entity *se)