On Wed 30-03-22 07:12:58, Christoph Hellwig wrote: > On Wed, Mar 30, 2022 at 02:42:51PM +0200, Jan Kara wrote: > > Convert BFQ to the new situation where bio->bi_blkg is initialized in > > bio_set_dev() and thus practically always valid. This allows us to save > > blkcg_gq lookup and noticeably simplify the code. > > Is there any case at all where it is not valid these days? > I can't think of any even if we have plenty of boilerplate code trying > to handle that case. So I didn't find any as well but I was not 100% sure since blkg_tryget_closest() seems like it *could* return NULL in some rare error cases. If we either modify blkg_tryget_closest() or handle that case in bio_associate_blkg_from_css() by using root_blkg, we can remove all the boilerplate code I assume. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
