ime looks at the remaining number of outstanding tasks
and sets the timeout to maximize small transaction operation.  If transactions
are large (take more than a few 10s of microseconds to complete) then
performance is not interrupt processing bound, so the small timeouts this
scheme generates are overridden by the time it takes for a completion to
arrive.

Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
^´NŒ‘%x