Re: [PATCH 26/27] mm: vmstat: Replace __count_zone_vm_events with a zone id equivalent

[Vlastimil Babka]

On 06/09/2016 08:04 PM, Mel Gorman wrote:
> This is partially a preparation patch for more vmstat work but it also
> has the slight advantage that __count_zid_vm_events is cheaper to
> calculate than __count_zone_vm_events().
>
> Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>

Acked-by: Vlastimil Babka <vbabka@xxxxxxx>

> ---
>  include/linux/vmstat.h | 5 ++---
>  mm/page_alloc.c        | 2 +-
>  2 files changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
> index 533948c93550..2feab717704d 100644
> --- a/include/linux/vmstat.h
> +++ b/include/linux/vmstat.h
> @@ -107,9 +107,8 @@ static inline void vm_events_fold_cpu(int cpu)
>  #define count_vm_vmacache_event(x) do {} while (0)
>  #endif
>
> -#define __count_zone_vm_events(item, zone, delta) \
> -		__count_vm_events(item##_NORMAL - ZONE_NORMAL + \
> -		zone_idx(zone), delta)
> +#define __count_zid_vm_events(item, zid, delta) \
> +	__count_vm_events(item##_NORMAL - ZONE_NORMAL + zid, delta)
>
>  /*
>   * Zone and node-based page accounting with per cpu differentials.
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 7c6c18a314a1..028d088633c4 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -2621,7 +2621,7 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
>  					  get_pcppage_migratetype(page));
>  	}
>
> -	__count_zone_vm_events(PGALLOC, zone, 1 << order);
> +	__count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
>  	zone_statistics(preferred_zone, zone, gfp_flags);
>  	local_irq_restore(flags);