[PATCH 1/4] nvme-tcp: per-controller I/O workqueues

[Christoph Hellwig]

Btw, I don't think brd is what we should optimize for.  brd does
synchronous I/O from ->submit_bio which makes it very non-typical.
Trying to get this as good as possible for QD=1 might be fine,
but once we have deeper queue depth and/or bigger I/O size it will
use a lot more time in the submission context (aka the workqueues here)
than a real device.