On Wed, May 03, 2023 at 09:25:21AM -0600, Keith Busch wrote: > On Wed, May 03, 2023 at 07:04:14AM +0200, Christoph Hellwig wrote: > > On Mon, May 01, 2023 at 08:33:04AM -0700, Keith Busch wrote: > > > From: Keith Busch <kbusch@xxxxxxxxxx> > > > > > > Passthrough requests don't go through the submit_bio() path, so all the > > > overhead of setting up the bio's cgroup is wasted cycles. Provide a path > > > to skip this setup. > > > > These days we should not need to set bi_bdev at all for passthrough, > > so I think we can just drop the assingment. > > We can't really skip it for polling since that needs a bio with a > bdev. I'll take another shot at detandling that requirement. I've got a new version ready to go that removes the bio and bi_dev requirement for polling uring commands, but passthrough still needs to set bi_bdev for metadata since it's used in bio_integrity_add_page(). I suppose we could have that just take the queue limits directly instead of extracting them from an assumed bi_dev.
