[074/178] mm: memcontrol: move PageMemcgKmem to the scope of CONFIG_MEMCG_KMEM

Commit Message

Andrew Morton April 30, 2021, 5:56 a.m. UTC

From: Muchun Song <[e-mail]>
Subject: mm: memcontrol: move PageMemcgKmem to the scope of CONFIG_MEMCG_KMEM

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.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Muchun Song <[e-mail]>
Acked-by: Roman Gushchin <[e-mail]>
Reviewed-by: Shakeel Butt <[e-mail]>
Acked-by: Johannes Weiner <[e-mail]>
Cc: Michal Hocko <[e-mail]>
Cc: Vladimir Davydov <[e-mail]>
Cc: Xiongchun Duan <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 include/linux/memcontrol.h |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

Patch

--- a/include/linux/memcontrol.h~mm-memcontrol-move-pagememcgkmem-to-the-scope-of-config_memcg_kmem
+++ a/include/linux/memcontrol.h
@@ -523,6 +523,7 @@  static inline struct mem_cgroup *page_me
 	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
@@ -537,7 +538,6 @@  static inline bool PageMemcgKmem(struct
 	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
@@ -579,6 +579,11 @@  static inline struct obj_cgroup **page_o
 }
 
 #else
+static inline bool PageMemcgKmem(struct page *page)
+{
+	return false;
+}
+
 static inline struct obj_cgroup **page_objcgs(struct page *page)
 {
 	return NULL;