linux-hardened/include
Tejun Heo 95a46c65e3 writeback: make bdi_has_dirty_io() take multiple bdi_writeback's into account
bdi_has_dirty_io() used to only reflect whether the root wb
(bdi_writeback) has dirty inodes.  For cgroup writeback support, it
needs to take all active wb's into account.  If any wb on the bdi has
dirty inodes, bdi_has_dirty_io() should return true.

To achieve that, as inode_wb_list_{move|del}_locked() now keep track
of the dirty state transition of each wb, the number of dirty wbs can
be counted in the bdi; however, bdi is already aggregating
wb->avg_write_bandwidth which can easily be guaranteed to be > 0 when
there are any dirty inodes by ensuring wb->avg_write_bandwidth can't
dip below 1.  bdi_has_dirty_io() can simply test whether
bdi->tot_write_bandwidth is zero or not.

While this bumps the value of wb->avg_write_bandwidth to one when it
used to be zero, this shouldn't cause any meaningful behavior
difference.

bdi_has_dirty_io() is made an inline function which tests whether
->tot_write_bandwidth is non-zero.  Also, WARN_ON_ONCE()'s on its
value are added to inode_wb_list_{move|del}_locked().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
..
acpi ACPICA: remove duplicate u8 typedef 2015-04-28 23:58:54 +02:00
asm-generic TTY/Serial patches for 4.1-rc1 2015-04-21 09:33:10 -07:00
clocksource
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-04-15 10:42:15 -07:00
drm Merge tag 'topic/drm-misc-2015-04-15' of git://anongit.freedesktop.org/drm-intel into drm-next 2015-04-16 08:34:24 +10:00
dt-bindings Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma 2015-04-24 09:49:37 -07:00
keys
kvm KVM/ARM changes for v4.1: 2015-04-07 18:09:20 +02:00
linux writeback: make bdi_has_dirty_io() take multiple bdi_writeback's into account 2015-06-02 08:33:36 -06:00
math-emu
media Merge branch 'patchwork' into v4l_for_linus 2015-04-21 06:12:35 -03:00
memory
misc
net net/bonding: Make DRV macros private 2015-04-26 22:59:53 -04:00
pcmcia
ras
rdma
rxrpc RxRPC: Handle VERSION Rx protocol packets 2015-04-01 16:31:26 +01:00
scsi SCSI: add 1024 max sectors black list flag 2015-04-27 09:38:06 -07:00
soc
sound ASoC: Fixes for v4.1 2015-04-30 19:08:06 +02:00
target Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-04-24 10:22:09 -07:00
trace writeback: move bandwidth related fields from backing_dev_info into bdi_writeback 2015-06-02 08:33:34 -06:00
uapi nbd: stop using req->cmd 2015-05-05 13:40:44 -06:00
video fbdev changes for v4.1 2015-04-20 15:16:25 -07:00
xen xenbus_client: Extend interface to support multi-page ring 2015-04-15 10:56:47 +01:00
Kbuild