summaryrefslogtreecommitdiff
path: root/kernel/sched
diff options
context:
space:
mode:
authorPeter Zijlstra <peterz@infradead.org>2019-11-08 14:15:55 +0100
committerIngo Molnar <mingo@kernel.org>2019-11-11 08:35:18 +0100
commit7277a34c6be0b2972bdd1fea88c7cef409bed5b4 (patch)
tree3676ac4c75f4b842510d8e9855d6bcc043d58ce7 /kernel/sched
parent6d5a763c303bc9d78b17361d30b692ba2facf9b4 (diff)
sched/fair: Better document newidle_balance()
Whilst chasing the pick_next_task() race, there was some confusion about the newidle_balance() return values. Document them. [ mingo: Minor edits. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: dietmar.eggemann@arm.com Cc: juri.lelli@redhat.com Cc: ktkhai@virtuozzo.com Cc: mgorman@suse.de Cc: qais.yousef@arm.com Cc: qperret@google.com Cc: rostedt@goodmis.org Cc: valentin.schneider@arm.com Cc: vincent.guittot@linaro.org Link: https://lkml.kernel.org/r/20191108131909.488364308@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched')
-rw-r--r--kernel/sched/fair.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 6e622f48c8de..c48a695a140c 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9941,6 +9941,11 @@ static inline void nohz_newidle_balance(struct rq *this_rq) { }
/*
* 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)
{