[PATCH 31/46] mm: numa: Structures for Migrate On Fault per NUMA migration rate limiting

[Mel Gorman <mgorman@suse.de>]

From: Andrea Arcangeli <aarcange@redhat.com>

This defines the per-node data used by Migrate On Fault in order to
rate limit the migration. The rate limiting is applied independently
to each destination node.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
 include/linux/mmzone.h |   13 +++++++++++++
 mm/page_alloc.c        |    5 +++++
 2 files changed, 18 insertions(+)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index a23923b..1ed16e5 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -717,6 +717,19 @@ typedef struct pglist_data {
 	struct task_struct *kswapd;	/* Protected by lock_memory_hotplug() */
 	int kswapd_max_order;
 	enum zone_type classzone_idx;
+#ifdef CONFIG_BALANCE_NUMA
+	/*
+	 * Lock serializing the per destination node AutoNUMA memory
+	 * migration rate limiting data.
+	 */
+	spinlock_t balancenuma_migrate_lock;
+
+	/* Rate limiting time interval */
+	unsigned long balancenuma_migrate_next_window;
+
+	/* Number of pages migrated during the rate limiting time interval */
+	unsigned long balancenuma_migrate_nr_pages;
+#endif
 } pg_data_t;
 
 #define node_present_pages(nid)	(NODE_DATA(nid)->node_present_pages)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 5953dc2..df58654 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4449,6 +4449,11 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
 	int ret;
 
 	pgdat_resize_init(pgdat);
+#ifdef CONFIG_BALANCE_NUMA
+	spin_lock_init(&pgdat->balancenuma_migrate_lock);
+	pgdat->balancenuma_migrate_nr_pages = 0;
+	pgdat->balancenuma_migrate_next_window = jiffies;
+#endif
 	init_waitqueue_head(&pgdat->kswapd_wait);
 	init_waitqueue_head(&pgdat->pfmemalloc_wait);
 	pgdat_page_cgroup_init(pgdat);
-- 
1.7.9.2