Re: [PATCH 4/4] arm64: tlb: set huge page size to stride for hugepage

[Kefeng Wang]

On 2023/7/31 19:11, Catalin Marinas wrote:
> On Mon, Jul 31, 2023 at 03:48:29PM +0800, Kefeng Wang wrote:
> > +/*
> > + * We cannot use leaf-only invalidation here, since we may be invalidating
> > + * table entries as part of collapsing hugepages or moving page tables.
> > + * Set the tlb_level to 0 because we can not get enough information here.
> > + */
> > +#define flush_tlb_range(vma, start, end)				\
> > +	__flush_tlb_range(vma, start, end,				\
> > +				((vma)->vm_flags & VM_HUGETLB)		\
> > +				? huge_page_size(hstate_vma(vma))	\
> > +				: PAGE_SIZE, false, 0)
>
> This won't work if we use the contiguous PTE to get 64K hugetlb pages on
> a 4K base page configuration. The 16 base pages in the range would have
> to be invalidated individually (the contig PTE bit is just a hint, the
> hardware may or may not take it into account).

Got it, the contig huge page is depended on hardware implementation,
but for normal hugepage(2M/1G), we could use this, right?
>