From: Peter Zijlstra <peterz@infradead.org>
Date: Thu, 24 Jul 2008 11:27:05 +0200

Well, not only lockdep, taking a very large number of locks is expensive
as well.

Right now it would be on the order of 16 or 32 for
real hardware.

Much less than the scheduler currently takes on some
of my systems, so currently you are the pot calling the
kettle black. :-)

USHORT_MAX is just the upper hard limit imposed by the
software interface merely as a side effect of storing
the queue number of the SKB as a u16.