sched: clean up __pick_last_entity() a bit

[sfrench/cifs-2.6.git] / kernel / sched_fair.c

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 72e25c7a3a186dc9830c206662dca4ad7d5892cb..c8e6492c5925f0dea503d48d04b9a12a6f0ade51 100644 (file)
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -202,17 +202,12 @@ static struct sched_entity *__pick_next_entity(struct cfs_rq *cfs_rq)
 
 static inline struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
 {
-       struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
-       struct sched_entity *se = NULL;
-       struct rb_node *parent;
+       struct rb_node *last = rb_last(&cfs_rq->tasks_timeline);
 
-       while (*link) {
-               parent = *link;
-               se = rb_entry(parent, struct sched_entity, run_node);
-               link = &parent->rb_right;
-       }
+       if (!last)
+               return NULL;
 
-       return se;
+       return rb_entry(last, struct sched_entity, run_node);
 }
 
 /**************************************************************
@@ -520,7 +515,7 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
 
        if (!initial) {
                /* sleeps upto a single latency don't count. */
-               if (sched_feat(NEW_FAIR_SLEEPERS) && entity_is_task(se))
+               if (sched_feat(NEW_FAIR_SLEEPERS))
                        vruntime -= sysctl_sched_latency;
 
                /* ensure we never gain time by being placed backwards. */
@@ -1106,7 +1101,11 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
        }
 
        gran = sysctl_sched_wakeup_granularity;
-       if (unlikely(se->load.weight != NICE_0_LOAD))
+       /*
+        * More easily preempt - nice tasks, while not making
+        * it harder for + nice tasks.
+        */
+       if (unlikely(se->load.weight > NICE_0_LOAD))
                gran = calc_delta_fair(gran, &se->load);
 
        if (pse->vruntime + gran < se->vruntime)