mm/swap.c: clean up *lru_cache_add* functions

In mm/swap.c, __lru_cache_add() is exported, but actually there are no
users outside this file.

This patch unexports __lru_cache_add(), and makes it static.  It also
exports lru_cache_add_file(), as it is use by cifs and fuse, which can
loaded as modules.

Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/swap.c b/mm/swap.c
index 9ce43ba..c0ed4d6 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -582,13 +582,7 @@
 }
 EXPORT_SYMBOL(mark_page_accessed);
 
-/*
- * Queue the page for addition to the LRU via pagevec. The decision on whether
- * to add the page to the [in]active [file|anon] list is deferred until the
- * pagevec is drained. This gives a chance for the caller of __lru_cache_add()
- * have the page added to the active list using mark_page_accessed().
- */
-void __lru_cache_add(struct page *page)
+static void __lru_cache_add(struct page *page)
 {
 	struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
 
@@ -598,11 +592,32 @@
 	pagevec_add(pvec, page);
 	put_cpu_var(lru_add_pvec);
 }
-EXPORT_SYMBOL(__lru_cache_add);
+
+/**
+ * lru_cache_add: add a page to the page lists
+ * @page: the page to add
+ */
+void lru_cache_add_anon(struct page *page)
+{
+	ClearPageActive(page);
+	__lru_cache_add(page);
+}
+
+void lru_cache_add_file(struct page *page)
+{
+	ClearPageActive(page);
+	__lru_cache_add(page);
+}
+EXPORT_SYMBOL(lru_cache_add_file);
 
 /**
  * lru_cache_add - add a page to a page list
  * @page: the page to be added to the LRU.
+ *
+ * Queue the page for addition to the LRU via pagevec. The decision on whether
+ * to add the page to the [in]active [file|anon] list is deferred until the
+ * pagevec is drained. This gives a chance for the caller of lru_cache_add()
+ * have the page added to the active list using mark_page_accessed().
  */
 void lru_cache_add(struct page *page)
 {