writeback: Do not sort b_io list only because of block device inode
authorJan Kara <jack@suse.cz>
Tue, 9 Jul 2013 14:36:45 +0000 (22:36 +0800)
committerFengguang Wu <fengguang.wu@intel.com>
Tue, 9 Jul 2013 14:36:45 +0000 (22:36 +0800)
commita8855990e382fc81c04187c5fdb48743307baf32
treee15bfdcd0a629be344d09113991dd2e613b747b7
parent8bb495e3f02401ee6f76d1b1d77f3ac9f079e376
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 <jack@suse.cz>
fs/block_dev.c
fs/fs-writeback.c
include/linux/fs.h