1 files changed, 20 insertions, 28 deletions

diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 9d2264ea460..d1473b2e948 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -6,30 +6,9 @@
 #include <linux/page-isolation.h>
 #include <linux/pageblock-flags.h>
 #include <linux/memory.h>
+#include <linux/hugetlb.h>
 #include "internal.h"
 
-/* called while holding zone->lock */
-static void set_pageblock_isolate(struct page *page)
-{
-	if (get_pageblock_migratetype(page) == MIGRATE_ISOLATE)
-		return;
-
-	set_pageblock_migratetype(page, MIGRATE_ISOLATE);
-	page_zone(page)->nr_pageblock_isolate++;
-}
-
-/* called while holding zone->lock */
-static void restore_pageblock_isolate(struct page *page, int migratetype)
-{
-	struct zone *zone = page_zone(page);
-	if (WARN_ON(get_pageblock_migratetype(page) != MIGRATE_ISOLATE))
-		return;
-
-	BUG_ON(zone->nr_pageblock_isolate <= 0);
-	set_pageblock_migratetype(page, migratetype);
-	zone->nr_pageblock_isolate--;
-}
-
 int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages)
 {
 	struct zone *zone;
@@ -80,7 +59,7 @@ out:
 		unsigned long nr_pages;
 		int migratetype = get_pageblock_migratetype(page);
 
-		set_pageblock_isolate(page);
+		set_pageblock_migratetype(page, MIGRATE_ISOLATE);
 		nr_pages = move_freepages_block(zone, page, MIGRATE_ISOLATE);
 
 		__mod_zone_freepage_state(zone, -nr_pages, migratetype);
@@ -103,7 +82,7 @@ void unset_migratetype_isolate(struct page *page, unsigned migratetype)
 		goto out;
 	nr_pages = move_freepages_block(zone, page, migratetype);
 	__mod_zone_freepage_state(zone, nr_pages, migratetype);
-	restore_pageblock_isolate(page, migratetype);
+	set_pageblock_migratetype(page, migratetype);
 out:
 	spin_unlock_irqrestore(&zone->lock, flags);
 }
@@ -248,9 +227,9 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
 	int ret;
 
 	/*
-	 * Note: pageblock_nr_page != MAX_ORDER. Then, chunks of free page
-	 * is not aligned to pageblock_nr_pages.
-	 * Then we just check pagetype fist.
+	 * Note: pageblock_nr_pages != MAX_ORDER. Then, chunks of free pages
+	 * are not aligned to pageblock_nr_pages.
+	 * Then we just check migratetype first.
 	 */
 	for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
 		page = __first_valid_page(pfn, pageblock_nr_pages);
@@ -260,7 +239,7 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
 	page = __first_valid_page(start_pfn, end_pfn - start_pfn);
 	if ((pfn < end_pfn) || !page)
 		return -EBUSY;
-	/* Check all pages are free or Marked as ISOLATED */
+	/* Check all pages are free or marked as ISOLATED */
 	zone = page_zone(page);
 	spin_lock_irqsave(&zone->lock, flags);
 	ret = __test_page_isolated_in_pageblock(start_pfn, end_pfn,
@@ -274,6 +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;