Commit 807a1bd2 authored Nov 12, 2013 by Toshi Kani Committed by Linus Torvalds Nov 13, 2013

mm: clear N_CPU from node_states at CPU offline



vmstat_cpuup_callback() is a CPU notifier callback, which marks N_CPU to a
node at CPU online event.  However, it does not update this N_CPU info at
CPU offline event.

Changed vmstat_cpuup_callback() to clear N_CPU when the last CPU in the
node is put into offline, i.e.  the node no longer has any online CPU.

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>

parent d7e0b37a

mm/vmstat.c

+15 −0

Original line number	Diff line number	Diff line
		@@ -1229,6 +1229,20 @@ static void start_cpu_timer(int cpu)
		schedule_delayed_work_on(cpu, work, __round_jiffies_relative(HZ, cpu));
		}

		static void vmstat_cpu_dead(int node)
		{
		int cpu;

		get_online_cpus();
		for_each_online_cpu(cpu)
		if (cpu_to_node(cpu) == node)
		goto end;

		node_clear_state(node, N_CPU);
		end:
		put_online_cpus();
		}

		/*
		* Use the cpu notifier to insure that the thresholds are recalculated
		* when necessary.
		@@ -1258,6 +1272,7 @@ static int vmstat_cpuup_callback(struct notifier_block *nfb,
		case CPU_DEAD:
		case CPU_DEAD_FROZEN:
		refresh_zone_stat_thresholds();
		vmstat_cpu_dead(cpu_to_node(cpu));
		break;
		default:
		break;