[PATCH v2 09/10] compaction: make compaction use in-order putback

[Minchan Kim <minchan.kim@gmail.com>]

Compaction is good solution to get contiguous page but it makes
LRU churing which is not good.
This patch makes that compaction code use in-order putback so
after compaction completion, migrated pages are keeping LRU ordering.

Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
---
 mm/compaction.c |   26 ++++++++++++++------------
 1 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/mm/compaction.c b/mm/compaction.c
index e218562..00e710a 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -28,7 +28,7 @@
  */
 struct compact_control {
 	struct list_head freepages;	/* List of free pages to migrate to */
-	struct list_head migratepages;	/* List of pages being migrated */
+	struct inorder_lru migratepages;/* List of pages being migrated */
 	unsigned long nr_freepages;	/* Number of isolated free pages */
 	unsigned long nr_migratepages;	/* Number of pages to migrate */
 	unsigned long free_pfn;		/* isolate_freepages search base */
@@ -210,7 +210,7 @@ static void acct_isolated(struct zone *zone, struct compact_control *cc)
 	struct page *page;
 	unsigned int count[2] = { 0, };
 
-	list_for_each_entry(page, &cc->migratepages, lru)
+	list_for_each_migrate_entry(page, &cc->migratepages, ilru)
 		count[!!page_is_file_cache(page)]++;
 
 	__mod_zone_page_state(zone, NR_ISOLATED_ANON, count[0]);
@@ -242,7 +242,7 @@ static unsigned long isolate_migratepages(struct zone *zone,
 	unsigned long low_pfn, end_pfn;
 	unsigned long last_pageblock_nr = 0, pageblock_nr;
 	unsigned long nr_scanned = 0, nr_isolated = 0;
-	struct list_head *migratelist = &cc->migratepages;
+	struct inorder_lru *migratelist = &cc->migratepages;
 	enum ISOLATE_PAGE_MODE mode = ISOLATE_BOTH;
 
 	/* Do not scan outside zone boundaries */
@@ -273,7 +273,7 @@ static unsigned long isolate_migratepages(struct zone *zone,
 	cond_resched();
 	spin_lock_irq(&zone->lru_lock);
 	for (; low_pfn < end_pfn; low_pfn++) {
-		struct page *page;
+		struct page *page, *prev_page;
 		bool locked = true;
 
 		/* give a chance to irqs before checking need_resched() */
@@ -330,14 +330,15 @@ static unsigned long isolate_migratepages(struct zone *zone,
 		/* Try isolate the page */
 		if (!cc->sync)
 			mode |= ISOLATE_CLEAN;
-		if (__isolate_lru_page(page, mode, 0) != 0)
+		if (__isolate_inorder_lru_page(page, mode, 0, &prev_page) != 0)
 			continue;
 
 		VM_BUG_ON(PageTransCompound(page));
 
 		/* Successfully isolated */
 		del_page_from_lru_list(zone, page, page_lru(page));
-		list_add(&page->lru, migratelist);
+		migratelist_add(page, prev_page, migratelist);
+
 		cc->nr_migratepages++;
 		nr_isolated++;
 
@@ -393,7 +394,7 @@ static void update_nr_listpages(struct compact_control *cc)
 	int nr_freepages = 0;
 	struct page *page;
 
-	list_for_each_entry(page, &cc->migratepages, lru)
+	list_for_each_migrate_entry(page, &cc->migratepages, ilru)
 		nr_migratepages++;
 	list_for_each_entry(page, &cc->freepages, lru)
 		nr_freepages++;
@@ -521,7 +522,8 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 			continue;
 
 		nr_migrate = cc->nr_migratepages;
-		err = migrate_pages(&cc->migratepages, compaction_alloc,
+		err = migrate_inorder_lru_pages(&cc->migratepages,
+				compaction_alloc,
 				(unsigned long)cc, false,
 				cc->sync);
 		update_nr_listpages(cc);
@@ -536,7 +538,7 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 
 		/* Release LRU pages not migrated */
 		if (err) {
-			putback_lru_pages(&cc->migratepages);
+			putback_inorder_lru_pages(&cc->migratepages);
 			cc->nr_migratepages = 0;
 		}
 
@@ -562,7 +564,7 @@ unsigned long compact_zone_order(struct zone *zone,
 		.sync = sync,
 	};
 	INIT_LIST_HEAD(&cc.freepages);
-	INIT_LIST_HEAD(&cc.migratepages);
+	INIT_MIGRATE_LIST(&cc.migratepages);
 
 	return compact_zone(zone, &cc);
 }
@@ -644,12 +646,12 @@ static int compact_node(int nid)
 
 		cc.zone = zone;
 		INIT_LIST_HEAD(&cc.freepages);
-		INIT_LIST_HEAD(&cc.migratepages);
+		INIT_MIGRATE_LIST(&cc.migratepages);
 
 		compact_zone(zone, &cc);
 
 		VM_BUG_ON(!list_empty(&cc.freepages));
-		VM_BUG_ON(!list_empty(&cc.migratepages));
+		VM_BUG_ON(!migratelist_empty(&cc.migratepages));
 	}
 
 	return 0;
-- 
1.7.0.4