mm: clean up mm_counter

Presently, per-mm statistics counter is defined by macro in sched.h

This patch modifies it to
  - defined in mm.h as inlinf functions
  - use array instead of macro's name creation.

This patch is for reducing patch size in future patch to modify
implementation of per-mm counter.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 2370504..35755a4 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -401,8 +401,8 @@
 		       "vsz:%lukB, anon-rss:%lukB, file-rss:%lukB\n",
 		       task_pid_nr(p), p->comm,
 		       K(p->mm->total_vm),
-		       K(get_mm_counter(p->mm, anon_rss)),
-		       K(get_mm_counter(p->mm, file_rss)));
+		       K(get_mm_counter(p->mm, MM_ANONPAGES)),
+		       K(get_mm_counter(p->mm, MM_FILEPAGES)));
 	task_unlock(p);
 
 	/*