md/bitmap: clean up plugging calls.

1/ use md_unplug in bitmap.c as we will soon be using bitmaps under
  arrays with no queue attached.

2/ Don't bother plugging the queue when we set a bit in the bitmap.
   The reason for this was to encourage as many bits as possible to
   get set before we unplug and write stuff out.
   However every personality already plugs the queue after
   bitmap_startwrite either directly (raid1/raid10) or be setting
   STRIPE_BIT_DELAY which causes the queue to be plugged later
   (raid5).

Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 1 insertions, 2 deletions

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 8af4d655b2d3..3f04699725db 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1296,7 +1296,7 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect
                         prepare_to_wait(&bitmap->overflow_wait, &__wait,
                                         TASK_UNINTERRUPTIBLE);
                         spin_unlock_irq(&bitmap->lock);
-                        blk_unplug(bitmap->mddev->queue);
+                        md_unplug(bitmap->mddev);
                         schedule();
                         finish_wait(&bitmap->overflow_wait, &__wait);
                         continue;
@@ -1306,7 +1306,6 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect
                 case 0:
                         bitmap_file_set_bit(bitmap, offset);
                         bitmap_count_page(bitmap, offset, 1);
-                        blk_plug_device_unlocked(bitmap->mddev->queue);
                         /* fall through */
                 case 1:
                         *bmc = 2;