mm: set N_CPU to node_states during boot
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@hp.com>
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 @@
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);