[RFC PATCH 3/3] powerpc/64s/radix: optimise TLB flush with precise TLB ranges in mmu_gather

[Linus Torvalds]

On Thu, Jun 14, 2018 at 11:49 AM Nicholas Piggin <npiggin at gmail.com> wrote:
>
> +#ifndef pte_free_tlb
>  #define pte_free_tlb(tlb, ptep, address)                       \
>         do {                                                    \
>                 __tlb_adjust_range(tlb, address, PAGE_SIZE);    \
>                 __pte_free_tlb(tlb, ptep, address);             \
>         } while (0)
> +#endif

Do you really want to / need to take over the whole pte_free_tlb macro?

I was hoping that you'd just replace the __tlv_adjust_range() instead.

Something like

 - replace the

        __tlb_adjust_range(tlb, address, PAGE_SIZE);

   with a "page directory" version:

        __tlb_free_directory(tlb, address, size);

 - have the default implementation for that be the old code:

        #ifndef __tlb_free_directory
          #define __tlb_free_directory(tlb,addr,size)
__tlb_adjust_range(tlb, addr, PAGE_SIZE)
        #endif

and that way architectures can now just hook into that
"__tlb_free_directory()" thing.

Hmm?

             Linus