Btrfs: Catch missed bios in the async bio submission thread

The async bio submission thread was missing some bios that were
added after it had decided there was no work left to do.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 9 insertions, 1 deletions

diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index d5f4e94f2ca2..f2e80f3768ec 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -349,6 +349,7 @@ int btrfs_requeue_work(struct btrfs_work *work)
 {
         struct btrfs_worker_thread *worker = work->worker;
         unsigned long flags;
+        int wake = 0;
 
         if (test_and_set_bit(WORK_QUEUED_BIT, &work->flags))
                 goto out;
@@ -367,10 +368,16 @@ int btrfs_requeue_work(struct btrfs_work *work)
                                &worker->workers->worker_list);
                 spin_unlock_irqrestore(&worker->workers->lock, flags);
         }
+        if (!worker->working) {
+                wake = 1;
+                worker->working = 1;
+        }
 
         spin_unlock_irqrestore(&worker->lock, flags);
-
+        if (wake)
+                wake_up_process(worker->task);
 out:
+
         return 0;
 }
 
@@ -397,6 +404,7 @@ int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work)
         }
 
         spin_lock_irqsave(&worker->lock, flags);
+
         atomic_inc(&worker->num_pending);
         check_busy_worker(worker);
         list_add_tail(&work->list, &worker->pending);