Re: [PATCH 13/27] mm, memcg: Move memcg limit enforcement from zones to nodes

Mel Gorman
2016-06-16T15:53:26Z

On Thu, Jun 16, 2016 at 05:06:46PM +0200, Vlastimil Babka wrote:
> >@@ -323,13 +319,10 @@ EXPORT_SYMBOL(memcg_kmem_enabled_key);
> >
> > #endif /* !CONFIG_SLOB */
> >
> >-static struct mem_cgroup_per_zone *
> >-mem_cgroup_zone_zoneinfo(struct mem_cgroup *memcg, struct zone *zone)
> >+static struct mem_cgroup_per_node *
> >+mem_cgroup_nodeinfo(struct mem_cgroup *memcg, pg_data_t *pgdat)
> > {
> >- int nid = zone_to_nid(zone);
> >- int zid = zone_idx(zone);
> >-
> >- return &memcg->nodeinfo[nid]->zoneinfo[zid];
> >+ return memcg->nodeinfo[pgdat->node_id];
>
> I've noticed most callers pass NODE_DATA(nid) as second parameter, which is
> quite wasteful to just obtain back the node_id (I doubt the compiler can
> know that they will be the same?). So it would be more efficient to use nid
> instead of pg_data_t pointer in the signature.
>

No harm in making the conversion, done now.

> > }
> >
> > /**
> >@@ -383,37 +376,35 @@ ino_t page_cgroup_ino(struct page *page)
> > return ino;
> > }
> >
> >-static struct mem_cgroup_per_zone *
> >+static struct mem_cgroup_per_node *
> > mem_cgroup_page_zoneinfo(struct mem_cgroup *memcg, struct page *page)
>
> This could be renamed to _nodeinfo()?
>

Renamed.

--
Mel Gorman
SUSE Labs