Re: [patch 15/26] Xen-paravirt_ops: Add apply_to_page_range() which applies a function to a pte range.

Jeremy Fitzhardinge
2007-03-16T17:08:49Z

Ingo Molnar wrote:
> nice one! I suspect we could simplify some of the less
> performance-critical open-coded pagetable walker loops in the kernel
> with this? (i'm not even sure it's all that much of a performance loss
> to pass a function pointer around - would be nice to convert say
> mprotect() to this and see the performance difference?)
>

apply_page_to_range has the side-effect of allocating all the pagetable
levels for the address range it walks. Xen uses this to populate
pagetables (for example, build out the pagetable, and let the hypervisor
plug a mapping into the pte page).

If that's OK for the other uses, then it should be good.

J