[RFC] Patch to improve TSO limitation formula in general

[Hans Petter Selasky]

Hi Rick,

I've collected all input from this discussion and committed the 
following patch to -current. I would like to MFC this to 10-stable 
before the coming 10-branchout. Sorry I'm rushing this a bit, hence 
there is only 2 weeks left until the branching happens.

http://svnweb.freebsd.org/changeset/base/271504

Thanks for all good input!

--HPS