Re: [tip:x86/mm] x86/mm/tlb: Leave lazy TLB mode at page table free time

[Peter Zijlstra]

On Tue, Jul 17, 2018 at 02:34:07AM -0700, tip-bot for Rik van Riel wrote:
> diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h
> index 3063125197ad..e811ef7b8350 100644
> --- a/include/asm-generic/tlb.h
> +++ b/include/asm-generic/tlb.h
> @@ -303,4 +303,14 @@ static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
>  
>  #define tlb_migrate_finish(mm) do {} while (0)
>  
> +/*
> + * Used to flush the TLB when page tables are removed, when lazy
> + * TLB mode may cause a CPU to retain intermediate translations
> + * pointing to about-to-be-freed page table memory.
> + */
> +#ifndef HAVE_TLB_FLUSH_REMOVE_TABLES
> +#define tlb_flush_remove_tables(mm) do {} while (0)
> +#define tlb_flush_remove_tables_local(mm) do {} while (0)
> +#endif

Is there a reason these are not inline functions, which gets us type
checking and the like?