[PATCH] Trivial optimization of ll_rw_block()

The ll_rw_block() needs to get ref-count only if it submits a buffer().  This
patch avoids the needless get/put of ref-count.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index 5e4a90ee103f..62cfd17dc5fe 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2867,22 +2867,22 @@ void ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
                 else if (test_set_buffer_locked(bh))
                         continue;
 
-                get_bh(bh);
                 if (rw == WRITE || rw == SWRITE) {
                         if (test_clear_buffer_dirty(bh)) {
                                 bh->b_end_io = end_buffer_write_sync;
+                                get_bh(bh);
                                 submit_bh(WRITE, bh);
                                 continue;
                         }
                 } else {
                         if (!buffer_uptodate(bh)) {
                                 bh->b_end_io = end_buffer_read_sync;
+                                get_bh(bh);
                                 submit_bh(rw, bh);
                                 continue;
                         }
                 }
                 unlock_buffer(bh);
-                put_bh(bh);
         }
 }