ext4: make __ext4_get_inode_loc plug

Add a blk_plug to prevent the inode table readahead from being
submitted as small I/O requests.

Signed-off-by: zhangjs <zachary@baishancloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
This commit is contained in:
zhangjs 2019-06-19 23:41:29 -04:00 committed by Theodore Ts'o
parent c60990b361
commit b03755ad6f

View file

@ -4570,6 +4570,7 @@ static int __ext4_get_inode_loc(struct inode *inode,
struct buffer_head *bh;
struct super_block *sb = inode->i_sb;
ext4_fsblk_t block;
struct blk_plug plug;
int inodes_per_block, inode_offset;
iloc->bh = NULL;
@ -4658,6 +4659,7 @@ static int __ext4_get_inode_loc(struct inode *inode,
* If we need to do any I/O, try to pre-readahead extra
* blocks from the inode table.
*/
blk_start_plug(&plug);
if (EXT4_SB(sb)->s_inode_readahead_blks) {
ext4_fsblk_t b, end, table;
unsigned num;
@ -4688,6 +4690,7 @@ static int __ext4_get_inode_loc(struct inode *inode,
get_bh(bh);
bh->b_end_io = end_buffer_read_sync;
submit_bh(REQ_OP_READ, REQ_META | REQ_PRIO, bh);
blk_finish_plug(&plug);
wait_on_buffer(bh);
if (!buffer_uptodate(bh)) {
EXT4_ERROR_INODE_BLOCK(inode, block,