Re: [PATCH v2 4/5] mm/page_alloc: Inline function to handle CONFIG_DEFERRED_STRUCT_PAGE_INIT

[Michal Hocko]

On Thu 19-07-18 15:27:39, osalvador@xxxxxxxxxxxxxxxxxx wrote:
> From: Oscar Salvador <osalvador@xxxxxxx>
> 
> Let us move the code between CONFIG_DEFERRED_STRUCT_PAGE_INIT
> to an inline function.

... to remove an ugly ifdef in the code.

Please always mention _why_ in the changelog. I can clearly see what
you've done in the diff.

> Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>

Acked-by: Michal Hocko <mhocko@xxxxxxxx>

> ---
>  mm/page_alloc.c | 25 ++++++++++++++++---------
>  1 file changed, 16 insertions(+), 9 deletions(-)
> 
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index f7a6f4e13f41..d77bc2a7ec2c 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -6379,6 +6379,21 @@ static void __ref alloc_node_mem_map(struct pglist_data *pgdat)
>  static void __ref alloc_node_mem_map(struct pglist_data *pgdat) { }
>  #endif /* CONFIG_FLAT_NODE_MEM_MAP */
>  
> +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
> +static inline void pgdat_set_deferred_range(pg_data_t *pgdat)
> +{
> +	/*
> +	 * We start only with one section of pages, more pages are added as
> +	 * needed until the rest of deferred pages are initialized.
> +	 */
> +	pgdat->static_init_pgcnt = min_t(unsigned long, PAGES_PER_SECTION,
> +						pgdat->node_spanned_pages);
> +	pgdat->first_deferred_pfn = ULONG_MAX;
> +}
> +#else
> +static inline void pgdat_set_deferred_range(pg_data_t *pgdat) {}
> +#endif
> +
>  void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
>  		unsigned long node_start_pfn, unsigned long *zholes_size)
>  {
> @@ -6404,16 +6419,8 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
>  				  zones_size, zholes_size);
>  
>  	alloc_node_mem_map(pgdat);
> +	pgdat_set_deferred_range(pgdat);
>  
> -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
> -	/*
> -	 * We start only with one section of pages, more pages are added as
> -	 * needed until the rest of deferred pages are initialized.
> -	 */
> -	pgdat->static_init_pgcnt = min_t(unsigned long, PAGES_PER_SECTION,
> -					 pgdat->node_spanned_pages);
> -	pgdat->first_deferred_pfn = ULONG_MAX;
> -#endif
>  	free_area_init_core(pgdat);
>  }
>  
> -- 
> 2.13.6
> 

-- 
Michal Hocko
SUSE Labs