On Fri, May 26, 2023 at 08:52:51AM +0000, Haifeng Xu wrote:
> In calculate_node_totalpages(), zone_start_pfn/zone_end_pfn are already
> calculated in zone_spanned_pages_in_node(), so use them as parameters
> instead of node_start_pfn/node_end_pfn and the duplicated calculation
> process can de dropped.
>
> Signed-off-by: Haifeng Xu <haifeng.xu@xxxxxxxxxx>
> Suggested-by: Mike Rapoport <rppt@xxxxxxxxxx>
Reviewed-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
> ---
> v2:
> - remove unrelated whitespace changes
> - do not replace pgdat->node_id with a local
> variable
> - remove redundant variable 'size'
> - add check that whether a zone is empty or not
> ---
> mm/mm_init.c | 30 ++++++++++++------------------
> 1 file changed, 12 insertions(+), 18 deletions(-)
>
> diff --git a/mm/mm_init.c b/mm/mm_init.c
> index f674e5798f7d..2d91bb52c619 100644
> --- a/mm/mm_init.c
> +++ b/mm/mm_init.c
> @@ -1166,20 +1166,15 @@ unsigned long __init absent_pages_in_range(unsigned long start_pfn,
> /* Return the number of page frames in holes in a zone on a node */
> static unsigned long __init zone_absent_pages_in_node(int nid,
> unsigned long zone_type,
> - unsigned long node_start_pfn,
> - unsigned long node_end_pfn)
> + unsigned long zone_start_pfn,
> + unsigned long zone_end_pfn)
> {
> - unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
> - unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
> - unsigned long zone_start_pfn, zone_end_pfn;
> unsigned long nr_absent;
>
> - zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
> - zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);
> + /* zone is empty, we don't have any absent pages */
> + if (zone_start_pfn == zone_end_pfn)
> + return 0;
>
> - adjust_zone_range_for_zone_movable(nid, zone_type,
> - node_start_pfn, node_end_pfn,
> - &zone_start_pfn, &zone_end_pfn);
> nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
>
> /*
> @@ -1272,7 +1267,7 @@ static void __init calculate_node_totalpages(struct pglist_data *pgdat,
> struct zone *zone = pgdat->node_zones + i;
> unsigned long zone_start_pfn, zone_end_pfn;
> unsigned long spanned, absent;
> - unsigned long size, real_size;
> + unsigned long real_size;
>
> spanned = zone_spanned_pages_in_node(pgdat->node_id, i,
> node_start_pfn,
> @@ -1280,23 +1275,22 @@ static void __init calculate_node_totalpages(struct pglist_data *pgdat,
> &zone_start_pfn,
> &zone_end_pfn);
> absent = zone_absent_pages_in_node(pgdat->node_id, i,
> - node_start_pfn,
> - node_end_pfn);
> + zone_start_pfn,
> + zone_end_pfn);
>
> - size = spanned;
> - real_size = size - absent;
> + real_size = spanned - absent;
>
> - if (size)
> + if (spanned)
> zone->zone_start_pfn = zone_start_pfn;
> else
> zone->zone_start_pfn = 0;
> - zone->spanned_pages = size;
> + zone->spanned_pages = spanned;
> zone->present_pages = real_size;
> #if defined(CONFIG_MEMORY_HOTPLUG)
> zone->present_early_pages = real_size;
> #endif
>
> - totalpages += size;
> + totalpages += spanned;
> realtotalpages += real_size;
> }
>
> --
> 2.25.1
>
--
Sincerely yours,
Mike.
