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