[PATCH 2/7] sched/fair: Better document newidle_balance()

[Peter Zijlstra]

Whilst chasing the pick_next_task() race, there was some confusion
about the newidle_balance() return values. Document them.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 kernel/sched/fair.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9920,6 +9920,11 @@ static inline void nohz_newidle_balance(
 /*
  * idle_balance is called by schedule() if this_cpu is about to become
  * idle. Attempts to pull tasks from other CPUs.
+ *
+ * Returns:
+ *  <0 - we released the lock and there are !fair tasks present
+ *   0 - failed, no new tasks
+ *  >0 - success, new (fair) tasks present
  */
 int newidle_balance(struct rq *this_rq, struct rq_flags *rf)
 {