fs: make fsync_buffers_list() plug

It used WRITE_SYNC_PLUG before and potentially submits a batch
of IO, so lets enable plugging for this case.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index 42534f67d71b..2e6b1a387b7e 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -743,8 +743,10 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list)
         struct list_head tmp;
         struct address_space *mapping;
         int err = 0, err2;
+        struct blk_plug plug;
 
         INIT_LIST_HEAD(&tmp);
+        blk_start_plug(&plug);
 
         spin_lock(lock);
         while (!list_empty(list)) {
@@ -781,6 +783,10 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list)
                 }
         }
 
+        spin_unlock(lock);
+        blk_finish_plug(&plug);
+        spin_lock(lock);
+
         while (!list_empty(&tmp)) {
                 bh = BH_ENTRY(tmp.prev);
                 get_bh(bh);