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, 1 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 03c64e9735fb..9d4e44e460e9 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -6627,7 +6627,7 @@ int md_allow_write(mddev_t *mddev)
 }
 EXPORT_SYMBOL_GPL(md_allow_write);
 
-static void md_unplug(mddev_t *mddev)
+void md_unplug(mddev_t *mddev)
 {
         if (mddev->queue)
                 blk_unplug(mddev->queue);