[dm-devel] [patch 5/5] block: use a driver-specific handler for the "inflight" value

[Christoph Hellwig]

On Thu, Nov 08, 2018 at 12:07:01PM -0500, Mike Snitzer wrote:
> Discussed doing that with Jens and reported as much here:
> 
> https://www.redhat.com/archives/dm-devel/2018-November/msg00068.html
> 
> And Jens gave additional context for why yet another attempt to switch
> block core's in_flight to percpu counters is doomed (having already been
> proposed and rejected twice):
> 
> https://www.redhat.com/archives/dm-devel/2018-November/msg00071.html
> 
> And yes, definitely should've cc'd linux-block (now added).

So how is dm different from the the other 3 handful of drivers using
the make_request interface that the per-cpu counters work for dm and
not the others?