workqueue: remove the lock from wq_sysfs_prep_attrs()
Reading to wq->unbound_attrs requires protection of either wq_pool_mutex
or wq->mutex, and wq_sysfs_prep_attrs() is called with wq_pool_mutex held,
so we don't need to grab wq->mutex here.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index bd4b24d..ad8dc2b 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4937,13 +4937,13 @@
{
struct workqueue_attrs *attrs;
+ lockdep_assert_held(&wq_pool_mutex);
+
attrs = alloc_workqueue_attrs(GFP_KERNEL);
if (!attrs)
return NULL;
- mutex_lock(&wq->mutex);
copy_workqueue_attrs(attrs, wq->unbound_attrs);
- mutex_unlock(&wq->mutex);
return attrs;
}