1 files changed, 27 insertions, 15 deletions

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 7c248dc30f41..652e8bdef9aa 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -266,6 +266,12 @@ static inline u64 min_vruntime(u64 min_vruntime, u64 vruntime)
 	return min_vruntime;
 }
 
+static inline int entity_before(struct sched_entity *a,
+				struct sched_entity *b)
+{
+	return (s64)(a->vruntime - b->vruntime) < 0;
+}
+
 static inline s64 entity_key(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
 	return se->vruntime - cfs_rq->min_vruntime;
@@ -605,9 +611,13 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
 static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
 #ifdef CONFIG_SCHEDSTATS
+	struct task_struct *tsk = NULL;
+
+	if (entity_is_task(se))
+		tsk = task_of(se);
+
 	if (se->sleep_start) {
 		u64 delta = rq_of(cfs_rq)->clock - se->sleep_start;
-		struct task_struct *tsk = task_of(se);
 
 		if ((s64)delta < 0)
 			delta = 0;
@@ -618,11 +628,11 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 		se->sleep_start = 0;
 		se->sum_sleep_runtime += delta;
 
-		account_scheduler_latency(tsk, delta >> 10, 1);
+		if (tsk)
+			account_scheduler_latency(tsk, delta >> 10, 1);
 	}
 	if (se->block_start) {
 		u64 delta = rq_of(cfs_rq)->clock - se->block_start;
-		struct task_struct *tsk = task_of(se);
 
 		if ((s64)delta < 0)
 			delta = 0;
@@ -633,17 +643,19 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 		se->block_start = 0;
 		se->sum_sleep_runtime += delta;
 
-		/*
-		 * Blocking time is in units of nanosecs, so shift by 20 to
-		 * get a milliseconds-range estimation of the amount of
-		 * time that the task spent sleeping:
-		 */
-		if (unlikely(prof_on == SLEEP_PROFILING)) {
-
-			profile_hits(SLEEP_PROFILING, (void *)get_wchan(tsk),
-				     delta >> 20);
+		if (tsk) {
+			/*
+			 * Blocking time is in units of nanosecs, so shift by
+			 * 20 to get a milliseconds-range estimation of the
+			 * amount of time that the task spent sleeping:
+			 */
+			if (unlikely(prof_on == SLEEP_PROFILING)) {
+				profile_hits(SLEEP_PROFILING,
+						(void *)get_wchan(tsk),
+						delta >> 20);
+			}
+			account_scheduler_latency(tsk, delta >> 10, 0);
 		}
-		account_scheduler_latency(tsk, delta >> 10, 0);
 	}
 #endif
 }
@@ -1017,7 +1029,7 @@ static void yield_task_fair(struct rq *rq)
 	/*
 	 * Already in the rightmost position?
 	 */
-	if (unlikely(!rightmost || rightmost->vruntime < se->vruntime))
+	if (unlikely(!rightmost || entity_before(rightmost, se)))
 		return;
 
 	/*
@@ -1713,7 +1725,7 @@ static void task_new_fair(struct rq *rq, struct task_struct *p)
 
 	/* 'curr' will be NULL if the child belongs to a different group */
 	if (sysctl_sched_child_runs_first && this_cpu == task_cpu(p) &&
-			curr && curr->vruntime < se->vruntime) {
+			curr && entity_before(curr, se)) {
 		/*
 		 * Upon rescheduling, sched_class::put_prev_task() will place
 		 * 'current' within the tree based on its new key value.