From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 091/131] mm: memcontrol: prepare cgroup vmstat infrastructure for native anon counters Date: Wed, 03 Jun 2020 16:01:51 -0700 Message-ID: <20200603230151.3eLAz1hqe%akpm@linux-foundation.org> References: <20200603155549.e041363450869eaae4c7f05b@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:47840 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726563AbgFCXIj (ORCPT ); Wed, 3 Jun 2020 19:08:39 -0400 In-Reply-To: <20200603155549.e041363450869eaae4c7f05b@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: akpm@linux-foundation.org, alex.shi@linux.alibaba.com, bsingharora@gmail.com, guro@fb.com, hannes@cmpxchg.org, hughd@google.com, iamjoonsoo.kim@lge.com, kirill@shutemov.name, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, shakeelb@google.com, torvalds@linux-foundation.org From: Johannes Weiner Subject: 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. Link: http://lkml.kernel.org/r/20200508183105.225460-9-hannes@cmpxchg.org Signed-off-by: Johannes Weiner Reviewed-by: Joonsoo Kim Cc: Alex Shi Cc: Hugh Dickins Cc: "Kirill A. Shutemov" Cc: Michal Hocko Cc: Roman Gushchin Cc: Shakeel Butt Cc: Balbir Singh Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 5 +++-- mm/memcontrol.c | 9 ++++++--- 2 files changed, 9 insertions(+), 5 deletions(-) --- a/include/linux/memcontrol.h~mm-memcontrol-prepare-cgroup-vmstat-infrastructure-for-native-anon-counters +++ a/include/linux/memcontrol.h @@ -709,16 +709,17 @@ static inline void mod_lruvec_state(stru 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); } --- a/mm/memcontrol.c~mm-memcontrol-prepare-cgroup-vmstat-infrastructure-for-native-anon-counters +++ a/mm/memcontrol.c @@ -1981,6 +1981,7 @@ void mem_cgroup_print_oom_group(struct m */ 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(struc 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_cgro */ 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); _