Re: [PATCH v6 11/18] arm64/mm: Split __flush_tlb_range() to elide trailing DSB

[Catalin Marinas]

On Thu, Feb 15, 2024 at 10:31:58AM +0000, Ryan Roberts wrote:
> Split __flush_tlb_range() into __flush_tlb_range_nosync() +
> __flush_tlb_range(), in the same way as the existing flush_tlb_page()
> arrangement. This allows calling __flush_tlb_range_nosync() to elide the
> trailing DSB. Forthcoming "contpte" code will take advantage of this
> when clearing the young bit from a contiguous range of ptes.
> 
> Ordering between dsb and mmu_notifier_arch_invalidate_secondary_tlbs()
> has changed, but now aligns with the ordering of __flush_tlb_page(). It
> has been discussed that __flush_tlb_page() may be wrong though.
> Regardless, both will be resolved separately if needed.
> 
> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
> Tested-by: John Hubbard <jhubbard@xxxxxxxxxx>
> Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>

Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>