On Fri 15-09-17 17:23:25, Kemi Wang wrote: [...] > @@ -2743,6 +2745,17 @@ static inline void zone_statistics(struct zone *preferred_zone, struct zone *z) > #ifdef CONFIG_NUMA > enum numa_stat_item local_stat = NUMA_LOCAL; > > + /* > + * skip zone_statistics() if vmstat is a coarse mode or zone statistics > + * is inactive in auto vmstat mode > + */ > + > + if (vmstat_mode) { > + if (vmstat_mode == VMSTAT_COARSE_MODE) > + return; > + } else if (disable_zone_statistics) > + return; > + > if (z->node != numa_node_id()) > local_stat = NUMA_OTHER; A jump label could make this completely out of the way for the case where every single cycle matters. -- Michal Hocko SUSE Labs