The page only can be marked as kmem when CONFIG_MEMCG_KMEM is enabled. So move PageMemcgKmem() to the scope of the CONFIG_MEMCG_KMEM. As a bonus, on !CONFIG_MEMCG_KMEM build some code can be compiled out. Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> --- include/linux/memcontrol.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 07c449af9c0f..d3ca8c8e7fc3 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -469,6 +469,7 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page) return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } +#ifdef CONFIG_MEMCG_KMEM /* * PageMemcgKmem - check if the page has MemcgKmem flag set * @page: a pointer to the page struct @@ -483,7 +484,6 @@ static inline bool PageMemcgKmem(struct page *page) return page->memcg_data & MEMCG_DATA_KMEM; } -#ifdef CONFIG_MEMCG_KMEM /* * page_objcgs - get the object cgroups vector associated with a page * @page: a pointer to the page struct @@ -544,6 +544,11 @@ static inline struct obj_cgroup *page_objcg(struct page *page) return (struct obj_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } #else +static inline bool PageMemcgKmem(struct page *page) +{ + return false; +} + static inline struct obj_cgroup **page_objcgs(struct page *page) { return NULL; -- 2.11.0