The per node numa_stat values for shmem don't change on
page migration for THP:
grep shmem /sys/fs/cgroup/machine.slice/.../memory.numa_stat:
shmem N0=1092616192 N1=10485760
shmem_thp N0=1092616192 N1=10485760
migratepages 9181 0 1:
shmem N0=0 N1=1103101952
shmem_thp N0=1092616192 N1=10485760
Fix that by updating shmem_thp counters likewise to shmem counters
on page migration.
Signed-off-by: Jan Glauber <jglauber@xxxxxxxxxxxxxxxx>
---
v3: Use folio_test_pmd_mappable instead of folio_test_transhuge
v2: Fix compile error
---
mm/migrate.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/mm/migrate.c b/mm/migrate.c
index 01cac26a3127..6ef8b1dea2e6 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -492,6 +492,11 @@ int folio_migrate_mapping(struct address_space *mapping,
if (folio_test_swapbacked(folio) && !folio_test_swapcache(folio)) {
__mod_lruvec_state(old_lruvec, NR_SHMEM, -nr);
__mod_lruvec_state(new_lruvec, NR_SHMEM, nr);
+
+ if (folio_test_pmd_mappable(folio)) {
+ __mod_lruvec_state(old_lruvec, NR_SHMEM_THPS, -nr);
+ __mod_lruvec_state(new_lruvec, NR_SHMEM_THPS, nr);
+ }
}
#ifdef CONFIG_SWAP
if (folio_test_swapcache(folio)) {
--
2.25.1
