vmscan: change type of vm_total_pages to unsigned long

This variable is calculated from nr_free_pagecache_pages so
change its type to unsigned long.
Signed-off-by: NZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/linux/swap.h

@@ -275,7 +275,7 @@ extern unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
-extern long vm_total_pages;
+extern unsigned long vm_total_pages;
 
 #ifdef CONFIG_NUMA
 extern int zone_reclaim_mode;

mm/vmscan.c

@@ -128,7 +128,7 @@ struct scan_control {
  * From 0 .. 100.  Higher means more swappy.
  */
 int vm_swappiness = 60;
-long vm_total_pages;	/* The total number of pages which the VM controls */
+unsigned long vm_total_pages;	/* The total number of pages which the VM controls */
 
 static LIST_HEAD(shrinker_list);
 static DECLARE_RWSEM(shrinker_rwsem);