Re: [PATCH 01/14] mm, compaction: Shrink compact_control

[Vlastimil Babka]

On 12/15/18 12:02 AM, Mel Gorman wrote:
> The isolate and migrate scanners should never isolate more than a pageblock
> of pages so unsigned int is sufficient saving 8 bytes on a 64-bit build.
> 
> Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>

Acked-by: Vlastimil Babka <vbabka@xxxxxxx>

> ---
>  mm/internal.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/internal.h b/mm/internal.h
> index 536bc2a839b9..5564841fce36 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -185,8 +185,8 @@ struct compact_control {
>  	struct list_head freepages;	/* List of free pages to migrate to */
>  	struct list_head migratepages;	/* List of pages being migrated */
>  	struct zone *zone;
> -	unsigned long nr_freepages;	/* Number of isolated free pages */
> -	unsigned long nr_migratepages;	/* Number of pages to migrate */
> +	unsigned int nr_freepages;	/* Number of isolated free pages */
> +	unsigned int nr_migratepages;	/* Number of pages to migrate */
>  	unsigned long total_migrate_scanned;
>  	unsigned long total_free_scanned;
>  	unsigned long free_pfn;		/* isolate_freepages search base */
>