1 files changed, 8 insertions, 3 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 956383844116..3b31fc05a0f1 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3287,10 +3287,15 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
         struct task_struct *p;
 
         /*
-         * Optimization: we know that if all tasks are in
-         * the fair class we can call that function directly:
+         * Optimization: we know that if all tasks are in the fair class we can
+         * call that function directly, but only if the @prev task wasn't of a
+         * higher scheduling class, because otherwise those loose the
+         * opportunity to pull in more work from other CPUs.
          */
-        if (likely(rq->nr_running == rq->cfs.h_nr_running)) {
+        if (likely((prev->sched_class == &idle_sched_class ||
+                    prev->sched_class == &fair_sched_class) &&
+                   rq->nr_running == rq->cfs.h_nr_running)) {
+
                 p = fair_sched_class.pick_next_task(rq, prev, rf);
                 if (unlikely(p == RETRY_TASK))
                         goto again;