On Tue, 2012-05-15 at 19:52 +1000, Nick Piggin wrote:

It could be warranted to change tlb_flush_mmu to a range API to
avoid doing the per-entry tracking which those architectures do? 

The per-entry could result in a much smaller range, there's no point in
flushing tlbs for unpopulated pages.

Anyway, I don't think even think we'd need to change the API for that,
you could track the entire range through tlb_start_vma() if you wanted
(although nobody does that IIRC).