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: Johannes Weiner <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Shakeel Butt <[email protected]> Cc: David Rientjes <[email protected]> Cc: Qian Cai <[email protected]> Acked-by: Kirill A. Shutemov <[email protected]> Reviewed-by: Kirill Tkhai <[email protected]> Signed-off-by: Yang Shi <[email protected]> --- mm/page_alloc.c | 1 + mm/swap.c | 2 +- mm/vmscan.c | 6 ++---- 3 files changed, 4 insertions(+), 5 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index df02a88..1d1c5d3 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -670,6 +670,7 @@ 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 ae30039..d4242c8 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); } diff --git a/mm/vmscan.c b/mm/vmscan.c index dbdc46a..b1b5e5f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1490,10 +1490,9 @@ static unsigned long shrink_page_list(struct list_head *page_list, * Is there need to periodically free_page_list? It would * appear not as the counts should be low */ - if (unlikely(PageTransHuge(page))) { - mem_cgroup_uncharge(page); + if (unlikely(PageTransHuge(page))) (*get_compound_page_dtor(page))(page); - } else + else list_add(&page->lru, &free_pages); continue; @@ -1914,7 +1913,6 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, if (unlikely(PageCompound(page))) { spin_unlock_irq(&pgdat->lru_lock); - mem_cgroup_uncharge(page); (*get_compound_page_dtor(page))(page); spin_lock_irq(&pgdat->lru_lock); } else -- 1.8.3.1
