On Tue, May 29, 2018 at 05:17:12PM -0400, Josef Bacik wrote: > From: Josef Bacik <jbacik@xxxxxx> > > Currently io.low uses a bi_cg_private to stash its private data for the > blkg, however other blkcg policies may want to use this as well. Since > we can get the private data out of the blkg, move this to bi_blkg in the > bio and make it generic, then we can use bio_associate_blkg() to attach > the blkg to the bio. > > Theoretically we could simply replace the bi_css with this since we can > get to all the same information from the blkg, however you have to > lookup the blkg, so for example wbc_init_bio() would have to lookup and > possibly allocate the blkg for the css it was trying to attach to the > bio. This could be problematic and result in us either not attaching > the css at all to the bio, or falling back to the root blkcg if we are > unable to allocate the corresponding blkg. > > So for now do this, and in the future if possible we could just replace > the bi_css with bi_blkg and update the helpers to do the correct > translation. > > Signed-off-by: Josef Bacik <jbacik@xxxxxx> Acked-by: Tejun Heo <tj@xxxxxxxxxx> Thanks. -- tejun