lru_activate
struct folio_batch *fbatch = &per_cpu(cpu_fbatches.lru_activate, cpu);
folio_batch_move_lru(fbatch, lru_activate);
folio_batch_add_and_move(folio, lru_activate);
lru_activate(lruvec, folio);
struct folio_batch lru_activate;
folio_batch_count(&fbatches->lru_activate) ||