mm: memcontrol: move kmem accounting code to CONFIG_MEMCG

The cgroup2 memory controller will account important in-kernel memory
consumers per default.  Move all necessary components to CONFIG_MEMCG.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 3ffee74..3627d5c 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -86,7 +86,7 @@
 #else
 # define SLAB_FAILSLAB		0x00000000UL
 #endif
-#ifdef CONFIG_MEMCG_KMEM
+#if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
 # define SLAB_ACCOUNT		0x04000000UL	/* Account to memcg */
 #else
 # define SLAB_ACCOUNT		0x00000000UL