mm: memcontrol: prepare cgroup vmstat infrastructure for native anon counters

Anonymous compound pages can be mapped by ptes, which means that if we
want to track NR_MAPPED_ANON, NR_ANON_THPS on a per-cgroup basis, we have
to be prepared to see tail pages in our accounting functions.

Make mod_lruvec_page_state() and lock_page_memcg() deal with tail pages
correctly, namely by redirecting to the head page which has the
page->mem_cgroup set up.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-9-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Johannes Weiner 2020-06-03 16:01:51 -07:00 committed by Linus Torvalds
parent 49e50d277b
commit 9da7b52168
2 changed files with 9 additions and 5 deletions

View File

@ -709,16 +709,17 @@ static inline void mod_lruvec_state(struct lruvec *lruvec,
static inline void __mod_lruvec_page_state(struct page *page,
enum node_stat_item idx, int val)
{
struct page *head = compound_head(page); /* rmap on tail pages */
pg_data_t *pgdat = page_pgdat(page);
struct lruvec *lruvec;
/* Untracked pages have no memcg, no lruvec. Update only the node */
if (!page->mem_cgroup) {
if (!head->mem_cgroup) {
__mod_node_page_state(pgdat, idx, val);
return;
}
lruvec = mem_cgroup_lruvec(page->mem_cgroup, pgdat);
lruvec = mem_cgroup_lruvec(head->mem_cgroup, pgdat);
__mod_lruvec_state(lruvec, idx, val);
}

View File

@ -1981,6 +1981,7 @@ void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
*/
struct mem_cgroup *lock_page_memcg(struct page *page)
{
struct page *head = compound_head(page); /* rmap on tail pages */
struct mem_cgroup *memcg;
unsigned long flags;
@ -2000,7 +2001,7 @@ struct mem_cgroup *lock_page_memcg(struct page *page)
if (mem_cgroup_disabled())
return NULL;
again:
memcg = page->mem_cgroup;
memcg = head->mem_cgroup;
if (unlikely(!memcg))
return NULL;
@ -2008,7 +2009,7 @@ again:
return memcg;
spin_lock_irqsave(&memcg->move_lock, flags);
if (memcg != page->mem_cgroup) {
if (memcg != head->mem_cgroup) {
spin_unlock_irqrestore(&memcg->move_lock, flags);
goto again;
}
@ -2051,7 +2052,9 @@ void __unlock_page_memcg(struct mem_cgroup *memcg)
*/
void unlock_page_memcg(struct page *page)
{
__unlock_page_memcg(page->mem_cgroup);
struct page *head = compound_head(page);
__unlock_page_memcg(head->mem_cgroup);
}
EXPORT_SYMBOL(unlock_page_memcg);