[RFC -V4 6/6] autonuma, memory tiering: Add page promotion counter

[Huang Ying]

To distinguish the number of promotion from the original inter-socket
NUMA balancing migration.  The counter is per-node (target node).
This is to identify imbalance among NUMA nodes.

Signed-off-by: "Huang, Ying" <ying.hu...@intel.com>
---
 include/linux/mmzone.h |  1 +
 mm/migrate.c           | 10 +++++++++-
 mm/vmstat.c            |  1 +
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index c10efdc92b17..b384489897b7 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -209,6 +209,7 @@ enum node_stat_item {
 #endif
 #ifdef CONFIG_NUMA_BALANCING
        PGPROMOTE_CANDIDATE,    /* candidate pages to promote */
+       PGPROMOTE_SUCCESS,      /* promote successfully */
 #endif
        NR_VM_NODE_STAT_ITEMS
 };
diff --git a/mm/migrate.c b/mm/migrate.c
index d8d80b111a6a..0f4106b6c4fe 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2161,8 +2161,13 @@ int migrate_misplaced_page(struct page *page, struct 
vm_area_struct *vma,
                        putback_lru_page(page);
                }
                isolated = 0;
-       } else
+       } else {
                count_vm_numa_event(NUMA_PAGE_MIGRATE);
+               if (sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING 
&&
+                   !node_is_toptier(page_to_nid(page)) && 
node_is_toptier(node))
+                       mod_node_page_state(NODE_DATA(node), PGPROMOTE_SUCCESS,
+                                           nr_succeeded);
+       }
        BUG_ON(!list_empty(&migratepages));
        return isolated;
 
@@ -2287,6 +2292,9 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
        mod_node_page_state(page_pgdat(page),
                        NR_ISOLATED_ANON + page_lru,
                        -HPAGE_PMD_NR);
+       if (!node_is_toptier(page_to_nid(page)) && node_is_toptier(node))
+               mod_node_page_state(NODE_DATA(node), PGPROMOTE_SUCCESS,
+                                   HPAGE_PMD_NR);
        return isolated;
 
 out_fail:
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 2e60cc0232ef..ba5f6f987711 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1217,6 +1217,7 @@ const char * const vmstat_text[] = {
 #endif
 #ifdef CONFIG_NUMA_BALANCING
        "pgpromote_candidate",
+       "pgpromote_success",
 #endif
 
        /* enum writeback_stat_item counters */
-- 
2.28.0