From becacb04fdd439d7d1f2a93739161706a2e3e947 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 30 Dec 2022 15:08:42 +0800 Subject: mm: memcg: add folio_memcg_check() Patch series "mm: convert page_idle/damon to use folios", v4. This patch (of 8): Convert page_memcg_check() into folio_memcg_check() and add a page_memcg_check() wrapper. The behaviour of page_memcg_check() is unchanged; tail pages always had a NULL ->memcg_data. Link: https://lkml.kernel.org/r/20221230070849.63358-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20221230070849.63358-2-wangkefeng.wang@huawei.com Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Kefeng Wang Cc: David Hildenbrand Cc: SeongJae Park Cc: Vishal Moola (Oracle) Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 40 ++++++++++++++++++++++++++-------------- 1 file changed, 26 insertions(+), 14 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 2e08b05bc6bf..26667bf16da5 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -466,34 +466,34 @@ static inline struct mem_cgroup *folio_memcg_rcu(struct folio *folio) } /* - * page_memcg_check - get the memory cgroup associated with a page - * @page: a pointer to the page struct + * folio_memcg_check - Get the memory cgroup associated with a folio. + * @folio: Pointer to the folio. * - * Returns a pointer to the memory cgroup associated with the page, - * or NULL. This function unlike page_memcg() can take any page - * as an argument. It has to be used in cases when it's not known if a page + * Returns a pointer to the memory cgroup associated with the folio, + * or NULL. This function unlike folio_memcg() can take any folio + * as an argument. It has to be used in cases when it's not known if a folio * has an associated memory cgroup pointer or an object cgroups vector or * an object cgroup. * - * For a non-kmem page any of the following ensures page and memcg binding + * For a non-kmem folio any of the following ensures folio and memcg binding * stability: * - * - the page lock + * - the folio lock * - LRU isolation - * - lock_page_memcg() + * - lock_folio_memcg() * - exclusive reference * - mem_cgroup_trylock_pages() * - * For a kmem page a caller should hold an rcu read lock to protect memcg - * associated with a kmem page from being released. + * For a kmem folio a caller should hold an rcu read lock to protect memcg + * associated with a kmem folio from being released. */ -static inline struct mem_cgroup *page_memcg_check(struct page *page) +static inline struct mem_cgroup *folio_memcg_check(struct folio *folio) { /* - * Because page->memcg_data might be changed asynchronously - * for slab pages, READ_ONCE() should be used here. + * Because folio->memcg_data might be changed asynchronously + * for slabs, READ_ONCE() should be used here. */ - unsigned long memcg_data = READ_ONCE(page->memcg_data); + unsigned long memcg_data = READ_ONCE(folio->memcg_data); if (memcg_data & MEMCG_DATA_OBJCGS) return NULL; @@ -508,6 +508,13 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page) return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } +static inline struct mem_cgroup *page_memcg_check(struct page *page) +{ + if (PageTail(page)) + return NULL; + return folio_memcg_check((struct folio *)page); +} + static inline struct mem_cgroup *get_mem_cgroup_from_objcg(struct obj_cgroup *objcg) { struct mem_cgroup *memcg; @@ -1170,6 +1177,11 @@ static inline struct mem_cgroup *folio_memcg_rcu(struct folio *folio) return NULL; } +static inline struct mem_cgroup *folio_memcg_check(struct folio *folio) +{ + return NULL; +} + static inline struct mem_cgroup *page_memcg_check(struct page *page) { return NULL; -- cgit v1.2.3-58-ga151