vmstat: update zone stat threshold when onlining a cpu

refresh_zone_stat_thresholds() calculates parameter based on the number of
online cpus.  It's called at cpu offlining but needs to be called at
onlining, too.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/mm/vmstat.c b/mm/vmstat.c
index f389168f9a83..a8d6b59e609a 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -998,6 +998,7 @@ static int __cpuinit vmstat_cpuup_callback(struct notifier_block *nfb,
         switch (action) {
         case CPU_ONLINE:
         case CPU_ONLINE_FROZEN:
+                refresh_zone_stat_thresholds();
                 start_cpu_timer(cpu);
                 node_set_state(cpu_to_node(cpu), N_CPU);
                 break;