From: Jan Kara <jack@suse.cz>
Date: Fri, 12 Apr 2013 04:03:19 +0000 (-0400)
Subject: ext4: clear buffer_uninit flag when submitting IO
X-Git-Tag: omap-for-v3.10/dt-fixes-for-merge-window~83^2~15
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=7b001d6a0c0c7b92e989c2c3b1d8e151f1df1acc

ext4: clear buffer_uninit flag when submitting IO

Currently noone cleared buffer_uninit flag. This results in writeback
needlessly marking io_end as needing extent conversion scanning extent
tree for extents to convert. So clear the buffer_uninit flag once the
buffer is submitted for IO and the flag is transformed into
EXT4_IO_END_UNWRITTEN flag.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
---

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 14f9837350d1..5929cd0baa20 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -387,7 +387,7 @@ submit_and_retry:
 	if (ret != bh->b_size)
 		goto submit_and_retry;
 	io_end = io->io_end;
-	if (buffer_uninit(bh))
+	if (test_clear_buffer_uninit(bh))
 		ext4_set_io_unwritten_flag(inode, io_end);
 	io_end->size += bh->b_size;
 	io->io_next_block++;