Re: [v2 PATCH 1/7] mm: memory: add orig_pmd to struct vm_fault

[Mel Gorman]

On Tue, Apr 13, 2021 at 02:24:10PM -0700, Yang Shi wrote:
> Add orig_pmd to struct vm_fault so the "orig_pmd" parameter used by huge page
> fault could be removed, just like its PTE counterpart does.
> 
> Signed-off-by: Yang Shi <shy828301@xxxxxxxxx>
>
> <SNIP>
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 25b9041f9925..9c5856f8cc81 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -547,6 +547,9 @@ struct vm_fault {
>  					 * the 'address'
>  					 */
>  	pte_t orig_pte;			/* Value of PTE at the time of fault */
> +	pmd_t orig_pmd;			/* Value of PMD at the time of fault,
> +					 * used by PMD fault only.
> +					 */
>  
>  	struct page *cow_page;		/* Page handler may use for COW fault */
>  	struct page *page;		/* ->fault handlers should return a

Could this be a union?

-- 
Mel Gorman
SUSE Labs