mm: rename NR_ANON_PAGES to NR_ANON_MAPPED

NR_FILE_PAGES  is the number of        file pages.
NR_FILE_MAPPED is the number of mapped file pages.
NR_ANON_PAGES  is the number of mapped anon pages.

This is unhelpful naming as it's easy to confuse NR_FILE_MAPPED and
NR_ANON_PAGES for mapped pages.  This patch renames NR_ANON_PAGES so we
have

NR_FILE_PAGES  is the number of        file pages.
NR_FILE_MAPPED is the number of mapped file pages.
NR_ANON_MAPPED is the number of mapped anon pages.

Link: http://lkml.kernel.org/r/1467970510-21195-19-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/rmap.c b/mm/rmap.c
index a46aef3..fdb3b5b 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1214,7 +1214,7 @@
 		 */
 		if (compound)
 			__inc_zone_page_state(page, NR_ANON_THPS);
-		__mod_node_page_state(page_pgdat(page), NR_ANON_PAGES, nr);
+		__mod_node_page_state(page_pgdat(page), NR_ANON_MAPPED, nr);
 	}
 	if (unlikely(PageKsm(page)))
 		return;
@@ -1258,7 +1258,7 @@
 		/* increment count (starts at -1) */
 		atomic_set(&page->_mapcount, 0);
 	}
-	__mod_node_page_state(page_pgdat(page), NR_ANON_PAGES, nr);
+	__mod_node_page_state(page_pgdat(page), NR_ANON_MAPPED, nr);
 	__page_set_anon_rmap(page, vma, address, 1);
 }
 
@@ -1375,7 +1375,7 @@
 		clear_page_mlock(page);
 
 	if (nr) {
-		__mod_node_page_state(page_pgdat(page), NR_ANON_PAGES, -nr);
+		__mod_node_page_state(page_pgdat(page), NR_ANON_MAPPED, -nr);
 		deferred_split_huge_page(page);
 	}
 }
@@ -1404,7 +1404,7 @@
 	 * these counters are not modified in interrupt context, and
 	 * pte lock(a spinlock) is held, which implies preemption disabled.
 	 */
-	__dec_node_page_state(page, NR_ANON_PAGES);
+	__dec_node_page_state(page, NR_ANON_MAPPED);
 
 	if (unlikely(PageMlocked(page)))
 		clear_page_mlock(page);