Re: [PATCH v3 4/6] mm/cma: remove ALLOC_CMA

[Vlastimil Babka]

On 05/26/2016 08:22 AM, js1304@xxxxxxxxx wrote:
> From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
>
> Now, all reserved pages for CMA region are belong to the ZONE_CMA
> and it only serves for GFP_HIGHUSER_MOVABLE. Therefore, we don't need to
> consider ALLOC_CMA at all.
>
> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
> ---
>  mm/internal.h   |  3 +--
>  mm/page_alloc.c | 27 +++------------------------
>  2 files changed, 4 insertions(+), 26 deletions(-)

[...]

> @@ -2833,10 +2827,8 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
>  		}
>
>  #ifdef CONFIG_CMA
> -		if ((alloc_flags & ALLOC_CMA) &&
> -		    !list_empty(&area->free_list[MIGRATE_CMA])) {
> +		if (!list_empty(&area->free_list[MIGRATE_CMA]))
>  			return true;
> -		}
>  #endif

Nitpick: it would be more logical to remove the whole block in this 
patch, as removing ALLOC_CMA means it's effectively false? Also less churn.