The later patch would make THP deferred split shrinker memcg aware, but it needs page->mem_cgroup information in THP destructor, which is called after mem_cgroup_uncharge() now.
So, move mem_cgroup_uncharge() from __page_cache_release() to compound page destructor, which is called by both THP and other compound pages except HugeTLB. And call it in __put_single_page() for single order page. Suggested-by: "Kirill A . Shutemov" <[email protected]> Cc: Kirill Tkhai <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Shakeel Butt <[email protected]> Cc: David Rientjes <[email protected]> Acked-by: Kirill A. Shutemov <[email protected]> Signed-off-by: Yang Shi <[email protected]> --- mm/page_alloc.c | 1 + mm/swap.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 6c9cf1e..53a7a6c 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -624,6 +624,7 @@ static void bad_page(struct page *page, const char *reason, void free_compound_page(struct page *page) { + mem_cgroup_uncharge(page); __free_pages_ok(page, compound_order(page)); } diff --git a/mm/swap.c b/mm/swap.c index 7ede3ed..170a725 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -71,12 +71,12 @@ static void __page_cache_release(struct page *page) spin_unlock_irqrestore(&pgdat->lru_lock, flags); } __ClearPageWaiters(page); - mem_cgroup_uncharge(page); } static void __put_single_page(struct page *page) { __page_cache_release(page); + mem_cgroup_uncharge(page); free_unref_page(page); } -- 1.8.3.1
