On Sat 15-06-19 11:24:46, Tejun Heo wrote:
> When writeback IOs are bounced through async layers, the IOs should
> only be accounted against the wbc from the original bdi writeback to
> avoid confusing cgroup inode ownership arbitration. Add
> wbc->no_wbc_acct to allow disabling wbc accounting. This will be used
> make btfs compression work well with cgroup IO control.
^^ btrfs
> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
...
> diff --git a/include/linux/writeback.h b/include/linux/writeback.h
> index 738a0c24874f..b8f5f000cde4 100644
> --- a/include/linux/writeback.h
> +++ b/include/linux/writeback.h
> @@ -68,6 +68,7 @@ struct writeback_control {
> unsigned for_reclaim:1; /* Invoked from the page allocator */
> unsigned range_cyclic:1; /* range_start is cyclic */
> unsigned for_sync:1; /* sync(2) WB_SYNC_ALL writeback */
> + unsigned no_wbc_acct:1; /* skip wbc IO accounting */
> #ifdef CONFIG_CGROUP_WRITEBACK
> struct bdi_writeback *wb; /* wb this writeback is issued under */
> struct inode *inode; /* inode being written out */
Can you add comment here that this is for writeback which has been already
accounted for?
Otherwise the patch looks good to me so feel free to add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
