Re: [PATCH v3 06/16] zsmalloc: squeeze inuse into page->mapping

Sergey Senozhatsky
2016-04-17T14:10:24Z

Hello,

On (03/30/16 16:12), Minchan Kim wrote:
[..]
> +static int get_zspage_inuse(struct page *first_page)
> +{
> + struct zs_meta *m;
> +
> + VM_BUG_ON_PAGE(!is_first_page(first_page), first_page);
> +
> + m = (struct zs_meta *)&first_page->mapping;
..
> +static void set_zspage_inuse(struct page *first_page, int val)
> +{
> + struct zs_meta *m;
> +
> + VM_BUG_ON_PAGE(!is_first_page(first_page), first_page);
> +
> + m = (struct zs_meta *)&first_page->mapping;
..
> +static void mod_zspage_inuse(struct page *first_page, int val)
> +{
> + struct zs_meta *m;
> +
> + VM_BUG_ON_PAGE(!is_first_page(first_page), first_page);
> +
> + m = (struct zs_meta *)&first_page->mapping;
..
> static void get_zspage_mapping(struct page *first_page,
> unsigned int *class_idx,
> enum fullness_group *fullness)
> {
> - unsigned long m;
> + struct zs_meta *m;
> +
> VM_BUG_ON_PAGE(!is_first_page(first_page), first_page);
> + m = (struct zs_meta *)&first_page->mapping;
..
> static void set_zspage_mapping(struct page *first_page,
> unsigned int class_idx,
> enum fullness_group fullness)
> {
> + struct zs_meta *m;
> +
> VM_BUG_ON_PAGE(!is_first_page(first_page), first_page);
>
> + m = (struct zs_meta *)&first_page->mapping;
> + m->fullness = fullness;
> + m->class = class_idx;
> }

a nitpick: this

struct zs_meta *m;
VM_BUG_ON_PAGE(!is_first_page(first_page), first_page);
m = (struct zs_meta *)&first_page->mapping;

seems to be common in several places, may be it makes sense to
factor it out and turn into a macro or a static inline helper?

other than that, looks good to me

Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>

-ss