diff --git a/include/linux/mm.h b/include/linux/mm.h
index 52041a638a7d..3f761db945d5 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2544,7 +2544,7 @@ int __must_check write_one_page(struct page *page);
 void task_dirty_inc(struct task_struct *tsk);
 
 /* readahead.c */
-#define VM_READAHEAD_PAGES	(SZ_128K / PAGE_SIZE)
+#define VM_READAHEAD_PAGES	(SZ_512K / PAGE_SIZE)
 
 int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
 			pgoff_t offset, unsigned long nr_to_read);