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authorJohannes Weiner <hannes@cmpxchg.org>2020-06-04 02:01:51 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-04 06:09:47 +0300
commit9da7b5216869f80e91f78403a57c72b42357758c (patch)
tree998e67b708477cb4fcb2be9f8aeb77369150a935 /mm/memcontrol.c
parent49e50d277ba2bb2c6e64632bc3193585674a2261 (diff)
downloadlinux-9da7b5216869f80e91f78403a57c72b42357758c.tar.xz
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>
Diffstat (limited to 'mm/memcontrol.c')
-rw-r--r--mm/memcontrol.c9
1 files changed, 6 insertions, 3 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index f82ae3723760..a875a97067a3 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -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);