Re: [RFC][PATCH] vm_operation to avoid pagefault/inval race

[Andrew Morton]

"Paul E. McKenney" <[e-mail]> wrote:
>
> So the general idea is to do something as follows, right?

It sounds reasonable.  A matter of putting together the appropriate
library functions and refactoring a few things.

> 
> o	Make a function, perhaps named something like
> 	install_new_page(), that does the PTE-installation
> 	and RSS-adjustment tasks currently performed by
> 	both do_no_page() and by do_anonymous_page().

That's similar to mm/fremap.c:install_page().  (Which forgets to call
update_mmu_cache().  Debatably a buglet.)

However there is not a lot of commonality between the various nopage()s and
there may not be a lot to be gained from all this.  There is subtle code in
there and it is performance-critical.  I'd be inclined to try to minimise
overall code churn in this work.