schedule_on_each_cpu(): use preempt_disable()
We take workqueue_mutex in there to keep CPU hotplug away. But
preempt_disable() will suffice for that.
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index b6fa5e6..1ea4bcb 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -638,7 +638,7 @@
if (!works)
return -ENOMEM;
- mutex_lock(&workqueue_mutex);
+ preempt_disable(); /* CPU hotplug */
for_each_online_cpu(cpu) {
struct work_struct *work = per_cpu_ptr(works, cpu);
@@ -646,7 +646,7 @@
set_bit(WORK_STRUCT_PENDING, work_data_bits(work));
__queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu), work);
}
- mutex_unlock(&workqueue_mutex);
+ preempt_enable();
flush_workqueue(keventd_wq);
free_percpu(works);
return 0;