mm: memory-hotplug: enable memory hotplug to handle hugepage

[firefly-linux-kernel-4.4.55.git] / mm / page_isolation.c

diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 0cee10ffb98d4cf8e6ad930faa1f4de925bdf3a5..d1473b2e9481731988695755a618baa0991556a7 100644 (file)
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -6,6 +6,7 @@
 #include <linux/page-isolation.h>
 #include <linux/pageblock-flags.h>
 #include <linux/memory.h>
+#include <linux/hugetlb.h>
 #include "internal.h"
 
 int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages)
@@ -252,6 +253,19 @@ struct page *alloc_migrate_target(struct page *page, unsigned long private,
 {
        gfp_t gfp_mask = GFP_USER | __GFP_MOVABLE;
 
+       /*
+        * TODO: allocate a destination hugepage from a nearest neighbor node,
+        * accordance with memory policy of the user process if possible. For
+        * now as a simple work-around, we use the next node for destination.
+        */
+       if (PageHuge(page)) {
+               nodemask_t src = nodemask_of_node(page_to_nid(page));
+               nodemask_t dst;
+               nodes_complement(dst, src);
+               return alloc_huge_page_node(page_hstate(compound_head(page)),
+                                           next_node(page_to_nid(page), dst));
+       }
+
        if (PageHighMem(page))
                gfp_mask |= __GFP_HIGHMEM;