Re: missing madvise functionality

[Rik van Riel <riel@redhat.com>]

Andrew Morton wrote:

> There are other ways of doing it - I guess we could use a new page flag to
> indicate that this is one-of-those-pages, and add new code to handle it in
> all the right places.

That's what I did.  I'm currently working on the
zap_page_range() side of things.

> One thing which we haven't sorted out with all this stuff: once the
> application has marked an address range (and some pages) as
> whatever-were-going-call-this-feature, how does the application undo that
> change? 

It doesn't have to do anything.  Just access the page and the
MMU will mark it dirty/accessed and the VM will not reclaim
it.

> What effect will things like mremap, madvise and mlock have upon
> these pages?

Good point.  I had not thought about these.

Would you mind if I sent an initial proof of concept
patch that does not take these into account, before
we decide on what should happen in these cases? :)

-- 
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