Re: [PATCH 3/3] mm/migrate: remove the duplicated code migrate_vma_collect_hole()

[Jerome Glisse]

On Tue, Aug 06, 2019 at 04:00:11PM +0800, Pingfan Liu wrote:
> After the previous patch which sees hole as invalid source,
> migrate_vma_collect_hole() has the same code as migrate_vma_collect_skip().
> Removing the duplicated code.

NAK this one too given previous NAK.

> 
> Signed-off-by: Pingfan Liu <kernelfans@xxxxxxxxx>
> Cc: "Jérôme Glisse" <jglisse@xxxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
> Cc: Jan Kara <jack@xxxxxxx>
> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxx>
> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> To: linux-mm@xxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> ---
>  mm/migrate.c | 22 +++-------------------
>  1 file changed, 3 insertions(+), 19 deletions(-)
> 
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 832483f..95e038d 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -2128,22 +2128,6 @@ struct migrate_vma {
>  	unsigned long		end;
>  };
>  
> -static int migrate_vma_collect_hole(unsigned long start,
> -				    unsigned long end,
> -				    struct mm_walk *walk)
> -{
> -	struct migrate_vma *migrate = walk->private;
> -	unsigned long addr;
> -
> -	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
> -		migrate->src[migrate->npages] = 0;
> -		migrate->dst[migrate->npages] = 0;
> -		migrate->npages++;
> -	}
> -
> -	return 0;
> -}
> -
>  static int migrate_vma_collect_skip(unsigned long start,
>  				    unsigned long end,
>  				    struct mm_walk *walk)
> @@ -2173,7 +2157,7 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp,
>  
>  again:
>  	if (pmd_none(*pmdp))
> -		return migrate_vma_collect_hole(start, end, walk);
> +		return migrate_vma_collect_skip(start, end, walk);
>  
>  	if (pmd_trans_huge(*pmdp)) {
>  		struct page *page;
> @@ -2206,7 +2190,7 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp,
>  				return migrate_vma_collect_skip(start, end,
>  								walk);
>  			if (pmd_none(*pmdp))
> -				return migrate_vma_collect_hole(start, end,
> +				return migrate_vma_collect_skip(start, end,
>  								walk);
>  		}
>  	}
> @@ -2337,7 +2321,7 @@ static void migrate_vma_collect(struct migrate_vma *migrate)
>  
>  	mm_walk.pmd_entry = migrate_vma_collect_pmd;
>  	mm_walk.pte_entry = NULL;
> -	mm_walk.pte_hole = migrate_vma_collect_hole;
> +	mm_walk.pte_hole = migrate_vma_collect_skip;
>  	mm_walk.hugetlb_entry = NULL;
>  	mm_walk.test_walk = NULL;
>  	mm_walk.vma = migrate->vma;
> -- 
> 2.7.5
>