kthread_worker: reorganize to prepare for flush_kthread_work() reimplementation

Make the following two non-functional changes.

* Separate out insert_kthread_work() from queue_kthread_work().

* Relocate struct kthread_flush_work and kthread_flush_work_fn()
  definitions above flush_kthread_work().

v2: Added lockdep_assert_held() in insert_kthread_work() as suggested
    by Andy Walls.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Andy Walls <awalls@md.metrocast.net>

1 files changed, 26 insertions, 16 deletions

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 3d3de633702..4bfbff36d44 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -378,6 +378,19 @@ repeat:
 }
 EXPORT_SYMBOL_GPL(kthread_worker_fn);
 
+/* insert @work before @pos in @worker */
+static void insert_kthread_work(struct kthread_worker *worker,
+                               struct kthread_work *work,
+                               struct list_head *pos)
+{
+        lockdep_assert_held(&worker->lock);
+
+        list_add_tail(&work->node, pos);
+        work->queue_seq++;
+        if (likely(worker->task))
+                wake_up_process(worker->task);
+}
+
 /**
  * queue_kthread_work - queue a kthread_work
  * @worker: target kthread_worker
@@ -395,10 +408,7 @@ bool queue_kthread_work(struct kthread_worker *worker,
 
         spin_lock_irqsave(&worker->lock, flags);
         if (list_empty(&work->node)) {
-                list_add_tail(&work->node, &worker->work_list);
-                work->queue_seq++;
-                if (likely(worker->task))
-                        wake_up_process(worker->task);
+                insert_kthread_work(worker, work, &worker->work_list);
                 ret = true;
         }
         spin_unlock_irqrestore(&worker->lock, flags);
@@ -406,6 +416,18 @@ bool queue_kthread_work(struct kthread_worker *worker,
 }
 EXPORT_SYMBOL_GPL(queue_kthread_work);
 
+struct kthread_flush_work {
+        struct kthread_work     work;
+        struct completion       done;
+};
+
+static void kthread_flush_work_fn(struct kthread_work *work)
+{
+        struct kthread_flush_work *fwork =
+                container_of(work, struct kthread_flush_work, work);
+        complete(&fwork->done);
+}
+
 /**
  * flush_kthread_work - flush a kthread_work
  * @work: work to flush
@@ -436,18 +458,6 @@ void flush_kthread_work(struct kthread_work *work)
 }
 EXPORT_SYMBOL_GPL(flush_kthread_work);
 
-struct kthread_flush_work {
-        struct kthread_work     work;
-        struct completion       done;
-};
-
-static void kthread_flush_work_fn(struct kthread_work *work)
-{
-        struct kthread_flush_work *fwork =
-                container_of(work, struct kthread_flush_work, work);
-        complete(&fwork->done);
-}
-
 /**
  * flush_kthread_worker - flush all current works on a kthread_worker
  * @worker: worker to flush