[PATCH v6 0/9] memcg: per cgroup dirty page accounting

[Vivek Goyal]

On Thu, Mar 17, 2011 at 01:43:50PM +0100, Johannes Weiner wrote:

[..]
> So structures roughly like this:
> 
> struct mem_cgroup {
> 	...
> 	/* key is struct backing_dev_info * */
> 	struct rb_root memcg_bdis;
> };
> 
> struct memcg_bdi {
> 	/* key is struct address_space * */
> 	struct rb_root memcg_mappings;
> 	struct rb_node node;
> };
> 
> struct memcg_mapping {
> 	struct address_space *mapping;
> 	struct mem_cgroup *memcg;
> 	struct rb_node node;
> 	atomic_t count;
> };
> 
> struct page_cgroup {
> 	...
> 	struct memcg_mapping *memcg_mapping;
> };

Johannes, didn't you want page->mapping to point to memcg_mapping instead
of increasing the size of page_cgroup?

Thanks
Vivek