mm: move page->mem_cgroup bad page handling into generic code

Now that the external page_cgroup data structure and its lookup is
gone, let the generic bad_page() check for page->mem_cgroup sanity.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 12 insertions, 20 deletions

diff --git a/mm/debug.c b/mm/debug.c
index 5ce45c9a29b5..0e58f3211f89 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -95,7 +95,10 @@ void dump_page_badflags(struct page *page, const char *reason,
                 dump_flags(page->flags & badflags,
                                 pageflag_names, ARRAY_SIZE(pageflag_names));
         }
-        mem_cgroup_print_bad_page(page);
+#ifdef CONFIG_MEMCG
+        if (page->mem_cgroup)
+                pr_alert("page->mem_cgroup:%p\n", page->mem_cgroup);
+#endif
 }
 
 void dump_page(struct page *page, const char *reason)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ab270e34ba3e..1869cb64d089 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3157,21 +3157,6 @@ static inline int mem_cgroup_move_swap_account(swp_entry_t entry,
 }
 #endif
 
-#ifdef CONFIG_DEBUG_VM
-bool mem_cgroup_bad_page_check(struct page *page)
-{
-        if (mem_cgroup_disabled())
-                return false;
-
-        return page->mem_cgroup != NULL;
-}
-
-void mem_cgroup_print_bad_page(struct page *page)
-{
-        pr_alert("page->mem_cgroup:%p\n", page->mem_cgroup);
-}
-#endif
-
 static DEFINE_MUTEX(memcg_limit_mutex);
 
 static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 22cfdeffbf69..a7198c065999 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -640,8 +640,10 @@ static inline int free_pages_check(struct page *page)
                 bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set";
                 bad_flags = PAGE_FLAGS_CHECK_AT_FREE;
         }
-        if (unlikely(mem_cgroup_bad_page_check(page)))
-                bad_reason = "cgroup check failed";
+#ifdef CONFIG_MEMCG
+        if (unlikely(page->mem_cgroup))
+                bad_reason = "page still charged to cgroup";
+#endif
         if (unlikely(bad_reason)) {
                 bad_page(page, bad_reason, bad_flags);
                 return 1;
@@ -900,8 +902,10 @@ static inline int check_new_page(struct page *page)
                 bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag set";
                 bad_flags = PAGE_FLAGS_CHECK_AT_PREP;
         }
-        if (unlikely(mem_cgroup_bad_page_check(page)))
-                bad_reason = "cgroup check failed";
+#ifdef CONFIG_MEMCG
+        if (unlikely(page->mem_cgroup))
+                bad_reason = "page still charged to cgroup";
+#endif
         if (unlikely(bad_reason)) {
                 bad_page(page, bad_reason, bad_flags);
                 return 1;