From a8855990e382fc81c04187c5fdb48743307baf32 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 9 Jul 2013 22:36:45 +0800 Subject: writeback: Do not sort b_io list only because of block device inode It is very likely that block device inode will be part of BDI dirty list as well. However it doesn't make sence to sort inodes on the b_io list just because of this inode (as it contains buffers all over the device anyway). So save some CPU cycles which is valuable since we hold relatively contented wb->list_lock. Signed-off-by: Jan Kara --- fs/fs-writeback.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'fs/fs-writeback.c') diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 3be57189efd5..cabdece4cb39 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -68,7 +68,7 @@ static inline struct backing_dev_info *inode_to_bdi(struct inode *inode) { struct super_block *sb = inode->i_sb; - if (strcmp(sb->s_type->name, "bdev") == 0) + if (sb_is_blkdev_sb(sb)) return inode->i_mapping->backing_dev_info; return sb->s_bdi; @@ -250,11 +250,13 @@ static int move_expired_inodes(struct list_head *delaying_queue, if (work->older_than_this && inode_dirtied_after(inode, *work->older_than_this)) break; + list_move(&inode->i_wb_list, &tmp); + moved++; + if (sb_is_blkdev_sb(inode->i_sb)) + continue; if (sb && sb != inode->i_sb) do_sb_sort = 1; sb = inode->i_sb; - list_move(&inode->i_wb_list, &tmp); - moved++; } /* just one sb in list, splice to dispatch_queue and we're done */ -- cgit v1.2.1