Re: [PATCH] flush_cache_page while pte valid

Ulrich Weigand
2002-11-12T01:02:04Z

Manfred Spraul wrote:

>Is it correct that this are 3 arch hooks that must appear back to back?
>What about one hook with all parameters?
>
> pte = ptep_get_and_clear_and_flush(ptep, vma, address);

This interface would help us on s390 very much. We have a hardware
instruction (INVALIDATE PAGE TABLE ENTRY) that implements the combination
of
pte = ptep_get_and_clear(ptep);
flush_tlb_page(vma, address);

very efficiently, but we cannot use it to implement flush_tlb_page
alone, because it requires the pte to be valid.

This is why our current in-tree flush_tlb_page is quite inefficient
(it always flushes the complete TLB) ...

If we had a combined hook, we could use our IPTE instruction.

Bye,
Ulrich

--
Dr. Ulrich Weigand
weigand@informatik.uni-erlangen.de