diff options
Diffstat (limited to 'kernel/sched/fair.c')
| -rw-r--r-- | kernel/sched/fair.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 25dffc03f0f6..94c3b8469cf6 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5912,6 +5912,20 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) (available_idle_cpu(prev) || sched_idle_cpu(prev))) return prev; + /* + * Allow a per-cpu kthread to stack with the wakee if the + * kworker thread and the tasks previous CPUs are the same. + * The assumption is that the wakee queued work for the + * per-cpu kthread that is now complete and the wakeup is + * essentially a sync wakeup. An obvious example of this + * pattern is IO completions. + */ + if (is_per_cpu_kthread(current) && + prev == smp_processor_id() && + this_rq()->nr_running <= 1) { + return prev; + } + /* Check a recently used CPU as a potential idle candidate: */ recent_used_cpu = p->recent_used_cpu; if (recent_used_cpu != prev && |