[PATCH] call mm/page-writeback.c:set_ratelimit() when new pages are hot-added

ratelimit_pages in page-writeback.c is recalculated (in set_ratelimit())
every time a CPU is hot-added/removed.  But this value is not recalculated
when new pages are hot-added.

This patch fixes that problem by calling set_ratelimit() when new pages
are hot-added.

[akpm@osdl.org: cleanups]
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 9576ed9..2053bb1 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -13,6 +13,7 @@
 #include <linux/compiler.h>
 #include <linux/module.h>
 #include <linux/pagevec.h>
+#include <linux/writeback.h>
 #include <linux/slab.h>
 #include <linux/sysctl.h>
 #include <linux/cpu.h>
@@ -192,6 +193,7 @@
 	if (need_zonelists_rebuild)
 		build_all_zonelists();
 	vm_total_pages = nr_free_pagecache_pages();
+	writeback_set_ratelimit();
 	return 0;
 }