Re: [PATCH v5 3/4] mm: introduce page memcg flags

From: Johannes Weiner
Date: Mon Oct 05 2020 - 10:59:26 EST


On Fri, Oct 02, 2020 at 10:25:58AM -0700, Roman Gushchin wrote:
> The lowest bit in page->memcg_data is used to distinguish between
> struct memory_cgroup pointer and a pointer to a objcgs array.
> All checks and modifications of this bit are open-coded.
>
> Let's formalize it using page memcg flags, defined in enum
> page_memcg_data_flags.
>
> Additional flags might be added later.
>
> Signed-off-by: Roman Gushchin <guro@xxxxxx>
> Reviewed-by: Shakeel Butt <shakeelb@xxxxxxxxxx>

Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>