From ed1403ec2bd463050e481cd29be40c504021676c Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Sat, 26 Jul 2014 12:03:59 +0800 Subject: [PATCH] kthread_work: wake up worker only when the worker is idle If the worker is already executing a work item when another is queued, we can safely skip wakeup without worrying about stalling queue thus avoiding waking up the busy worker spuriously. Spurious wakeups should be fine but still isn't nice and avoiding it is trivial here. tj: Updated description. Signed-off-by: Lai Jiangshan Signed-off-by: Tejun Heo --- kernel/kthread.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/kthread.c b/kernel/kthread.c index c2390f41307b..ef483220e855 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -591,7 +591,7 @@ static void insert_kthread_work(struct kthread_worker *worker, list_add_tail(&work->node, pos); work->worker = worker; - if (likely(worker->task)) + if (!worker->current_work && likely(worker->task)) wake_up_process(worker->task); }