After a system booted, N_CPU is not set to any node as has_cpu shows an empty line. # cat /sys/devices/system/node/has_cpu (show-empty-line) setup_vmstat() registers its CPU notifier callback, vmstat_cpuup_callback(), which marks N_CPU to a node when a CPU is put into online. However, setup_vmstat() is called after all CPUs are launched in the boot sequence. Changed setup_vmstat() to mark N_CPU to the nodes with online CPUs at boot, which is consistent with other operations in vmstat_cpuup_callback(), i.e. start_cpu_timer() and refresh_zone_stat_thresholds(). Also added get_online_cpus() to protect the for_each_online_cpu() loop. Signed-off-by: Toshi Kani <toshi.kani@xxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx> --- mm/vmstat.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/mm/vmstat.c b/mm/vmstat.c index 9bb3145..0a1f7de 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1276,8 +1276,12 @@ static int __init setup_vmstat(void) register_cpu_notifier(&vmstat_notifier); - for_each_online_cpu(cpu) + get_online_cpus(); + for_each_online_cpu(cpu) { start_cpu_timer(cpu); + node_set_state(cpu_to_node(cpu), N_CPU); + } + put_online_cpus(); #endif #ifdef CONFIG_PROC_FS proc_create("buddyinfo", S_IRUGO, NULL, &fragmentation_file_operations); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>