On 3/23/21 2:12 PM, Liu Shixin wrote:
> From: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
>
> The start_pfn and end_pfn are already available in move_freepages_block(),
> there is no need to go back and forth between page and pfn in move_freepages
> and move_freepages_block, and pfn_valid_within() should validate pfn first
> before touching the page.
>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
> Signed-off-by: Liu Shixin <liushixin2@xxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Agreed with Matthew's suggestion, also:
> @@ -2468,25 +2469,22 @@ static int move_freepages(struct zone *zone,
> int move_freepages_block(struct zone *zone, struct page *page,
> int migratetype, int *num_movable)
> {
> - unsigned long start_pfn, end_pfn;
> - struct page *start_page, *end_page;
> + unsigned long start_pfn, end_pfn, pfn;
>
> if (num_movable)
> *num_movable = 0;
>
> - start_pfn = page_to_pfn(page);
> - start_pfn = start_pfn & ~(pageblock_nr_pages-1);
> - start_page = pfn_to_page(start_pfn);
> - end_page = start_page + pageblock_nr_pages - 1;
> + pfn = page_to_pfn(page);
> + start_pfn = pfn & ~(pageblock_nr_pages - 1);
Since you touch this already, consider pageblock_start_pfn()
> end_pfn = start_pfn + pageblock_nr_pages - 1;
I'd also drop the "- 1" here and instead adjust the for loop's ending condition
from "pfn <= end_pfn" to "pfn < end_pfn" as that's more common way of doing it.
Thanks.
>
> /* Do not cross zone boundaries */
> if (!zone_spans_pfn(zone, start_pfn))
> - start_page = page;
> + start_pfn = pfn;
> if (!zone_spans_pfn(zone, end_pfn))
> return 0;
>
> - return move_freepages(zone, start_page, end_page, migratetype,
> + return move_freepages(zone, start_pfn, end_pfn, migratetype,
> num_movable);
> }
>
>
