1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 046084ebb1fb..1929deb3f29d 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1091,6 +1091,8 @@ static const u32 prio_to_wmult[40] = {
 
 #define DEQUEUE_SLEEP		1
 
+#define RETRY_TASK		((void *)-1UL)
+
 struct sched_class {
 	const struct sched_class *next;
 
@@ -1105,6 +1107,9 @@ struct sched_class {
 	 * It is the responsibility of the pick_next_task() method that will
 	 * return the next task to call put_prev_task() on the @prev task or
 	 * something equivalent.
+	 *
+	 * May return RETRY_TASK when it finds a higher prio class has runnable
+	 * tasks.
 	 */
 	struct task_struct * (*pick_next_task) (struct rq *rq,
 						struct task_struct *prev);