writeback: don't resort for a single super_block in move_expired_inodes()
If we only moved inodes from a single super_block to the temporary
list, there's no point in doing a resort for multiple super_blocks.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index b27406d..225c7316 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -336,17 +336,27 @@
{
LIST_HEAD(tmp);
struct list_head *pos, *node;
- struct super_block *sb;
+ struct super_block *sb = NULL;
struct inode *inode;
+ int do_sb_sort = 0;
while (!list_empty(delaying_queue)) {
inode = list_entry(delaying_queue->prev, struct inode, i_list);
if (older_than_this &&
inode_dirtied_after(inode, *older_than_this))
break;
+ if (sb && sb != inode->i_sb)
+ do_sb_sort = 1;
+ sb = inode->i_sb;
list_move(&inode->i_list, &tmp);
}
+ /* just one sb in list, splice to dispatch_queue and we're done */
+ if (!do_sb_sort) {
+ list_splice(&tmp, dispatch_queue);
+ return;
+ }
+
/* Move inodes from one superblock together */
while (!list_empty(&tmp)) {
inode = list_entry(tmp.prev, struct inode, i_list);