[PATCH v3 3/3] memory tiering: count PGPROMOTE_SUCCESS when mem tiering is enabled.

[Zi Yan]

memory tiering can be enabled/disabled at runtime and
sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING is used to check
it. In migrate_misplaced_folio(), the check is missing when
PGPROMOTE_SUCCESS is incremented. Add the missing check.

Reported-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Closes: https://lore.kernel.org/linux-mm/f4ae2c9c-fe40-4807-bdb2-64cf2d716c1a@xxxxxxxxxx/
Fixes: 33024536bafd ("memory tiering: hot page selection with hint page fault latency")
Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
---
 mm/migrate.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index e7296c0fb5d5..826afb82ca56 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2630,7 +2630,9 @@ int migrate_misplaced_folio(struct folio *folio, struct vm_area_struct *vma,
 		putback_movable_pages(&migratepages);
 	if (nr_succeeded) {
 		count_vm_numa_events(NUMA_PAGE_MIGRATE, nr_succeeded);
-		if (!node_is_toptier(folio_nid(folio)) && node_is_toptier(node))
+		if ((sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING)
+		    && !node_is_toptier(folio_nid(folio))
+		    && node_is_toptier(node))
 			mod_node_page_state(pgdat, PGPROMOTE_SUCCESS,
 					    nr_succeeded);
 	}
-- 
2.43.0