kthread_work: make lockdep happy

spinlock in kthread_worker and wait_queue_head in kthread_work both
should be lockdep sensible, so change the interface to make it
suiltable for CONFIG_LOCKDEP.

tj: comment update

Reported-by: Nicolas <nicolas.mailhot@laposte.net>
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Signed-off-by: Andy Walls <awalls@md.metrocast.net>
Tested-by: Andy Walls <awalls@md.metrocast.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 2dc3786349d1..ca61bbdd44b2 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -265,6 +265,17 @@ int kthreadd(void *unused)
         return 0;
 }
 
+void __init_kthread_worker(struct kthread_worker *worker,
+                                const char *name,
+                                struct lock_class_key *key)
+{
+        spin_lock_init(&worker->lock);
+        lockdep_set_class_and_name(&worker->lock, key, name);
+        INIT_LIST_HEAD(&worker->work_list);
+        worker->task = NULL;
+}
+EXPORT_SYMBOL_GPL(__init_kthread_worker);
+
 /**
  * kthread_worker_fn - kthread function to process kthread_worker
  * @worker_ptr: pointer to initialized kthread_worker