summaryrefslogtreecommitdiff
path: root/mm/vmstat.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/vmstat.c')
-rw-r--r--mm/vmstat.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 0b0fc3b77789..e60b36f5f0a9 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -342,6 +342,12 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
long t;
if (vmstat_item_in_bytes(item)) {
+ /*
+ * Only cgroups use subpage accounting right now; at
+ * the global level, these items still change in
+ * multiples of whole pages. Store them as pages
+ * internally to keep the per-cpu counters compact.
+ */
VM_WARN_ON_ONCE(delta & (PAGE_SIZE - 1));
delta >>= PAGE_SHIFT;
}
@@ -551,6 +557,12 @@ static inline void mod_node_state(struct pglist_data *pgdat,
long o, n, t, z;
if (vmstat_item_in_bytes(item)) {
+ /*
+ * Only cgroups use subpage accounting right now; at
+ * the global level, these items still change in
+ * multiples of whole pages. Store them as pages
+ * internally to keep the per-cpu counters compact.
+ */
VM_WARN_ON_ONCE(delta & (PAGE_SIZE - 1));
delta >>= PAGE_SHIFT;
}