[ofa-general] Re: [PATCH] mmu notifier #v11

[Christoph Lameter]

On Sat, 5 Apr 2008, Andrea Arcangeli wrote:

> In short when working with single pages it's a waste to block the
> secondary-mmu page fault, because it's zero cost to invalidate_page
> before put_page. Not even GRU need to do that.

That depends on what the notifier is being used for. Some serialization 
with the external mappings has to be done anyways. And its cleaner to have 
one API that does a lock/unlock scheme. Atomic operations can easily lead
to races.