From: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> Subject: mm: move mem_cgroup_uncharge out of __page_cache_release() A later patch makes 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. Link: http://lkml.kernel.org/r/1565144277-36240-3-git-send-email-yang.shi@xxxxxxxxxxxxxxxxx Signed-off-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> Suggested-by: "Kirill A . Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Reviewed-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Qian Cai <cai@xxxxxx> Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 1 + mm/swap.c | 2 +- mm/vmscan.c | 6 ++---- 3 files changed, 4 insertions(+), 5 deletions(-) --- a/mm/page_alloc.c~mm-move-mem_cgroup_uncharge-out-of-__page_cache_release +++ a/mm/page_alloc.c @@ -670,6 +670,7 @@ out: void free_compound_page(struct page *page) { + mem_cgroup_uncharge(page); __free_pages_ok(page, compound_order(page)); } --- a/mm/swap.c~mm-move-mem_cgroup_uncharge-out-of-__page_cache_release +++ a/mm/swap.c @@ -71,12 +71,12 @@ static void __page_cache_release(struct 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); } --- a/mm/vmscan.c~mm-move-mem_cgroup_uncharge-out-of-__page_cache_release +++ a/mm/vmscan.c @@ -1487,10 +1487,9 @@ free_it: * 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; @@ -1911,7 +1910,6 @@ static unsigned noinline_for_stack move_ 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 _
