enum node_stat_item item, int delta)
{
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;
}