On Tue, Sep 11, 2018 at 02:41:28PM -0400, Dennis Zhou wrote: > From: "Dennis Zhou (Facebook)" <dennisszhou@xxxxxxxxx> > > There are several scenarios where blkg_lookup_create can fail. Examples > include the blkcg dying, request_queue is dying, or simply being OOM. At > the end of the day, most handle this by simply falling back to the > q->root_blkg and calling it a day. > > This patch implements the notion of closest blkg. During > blkg_lookup_create, if it fails to create, return the closest blkg > found or the q->root_blkg. blkg_try_get_closest is introduced and used > during association so a bio is always attached to a blkg. > > Signed-off-by: Dennis Zhou <dennisszhou@xxxxxxxxx> Acked-by: Tejun Heo <tj@xxxxxxxxxx> Thanks. -- tejun
