Install the callbacks via the state machine, but do not invoke them as we
can initialize the node state without calling the callbacks on all online
CPUs.
start_shepherd_timer() is now called outside the get_online_cpus() block
which is safe as it only operates on cpu possible mask.
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Vlastimil Babka <vba...@suse.cz>
Cc: Mel Gorman <mgor...@techsingularity.net>
Cc: Johannes Weiner <han...@cmpxchg.org>
Cc: linux...@kvack.org
Signed-off-by: Sebastian Andrzej Siewior <bige...@linutronix.de>
Signed-off-by: Thomas Gleixner <t...@linutronix.de>
---
include/linux/cpuhotplug.h | 1 +
mm/vmstat.c | 76 +++++++++++++++++++++-------------------------
2 files changed, 36 insertions(+), 41 deletions(-)
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 18bcfeb2463e..4ebd1bc27f8d 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -20,6 +20,7 @@ enum cpuhp_state {
CPUHP_VIRT_NET_DEAD,
CPUHP_SLUB_DEAD,
CPUHP_MM_WRITEBACK_DEAD,
+ CPUHP_MM_VMSTAT_DEAD,
CPUHP_SOFTIRQ_DEAD,
CPUHP_NET_MVNETA_DEAD,
CPUHP_CPUIDLE_DEAD,
diff --git a/mm/vmstat.c b/mm/vmstat.c
index b96dcec7e7d7..dfe3cb9f2c36 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1726,64 +1726,58 @@ static void __init init_cpu_node_state(void)
node_set_state(node, N_CPU);
}
-static void vmstat_cpu_dead(int node)
+static int vmstat_cpu_online(unsigned int cpu)
+{
+ refresh_zone_stat_thresholds();
+ node_set_state(cpu_to_node(cpu), N_CPU);
+ return 0;
+}
+
+static int vmstat_cpu_down_prep(unsigned int cpu)
+{
+ cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu));
+ return 0;
+}
+
+static int vmstat_cpu_dead(unsigned int cpu)
{
const struct cpumask *node_cpus;
+ int node;
+ node = cpu_to_node(cpu);
+
+ refresh_zone_stat_thresholds();
node_cpus = cpumask_of_node(node);
if (cpumask_weight(node_cpus) > 0)
- return;
+ return 0;
node_clear_state(node, N_CPU);
+ return 0;
}
-/*
- * Use the cpu notifier to insure that the thresholds are recalculated
- * when necessary.
- */
-static int vmstat_cpuup_callback(struct notifier_block *nfb,
- unsigned long action,
- void *hcpu)
-{
- long cpu = (long)hcpu;
-
- switch (action) {
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- refresh_zone_stat_thresholds();
- node_set_state(cpu_to_node(cpu), N_CPU);
- break;
- case CPU_DOWN_PREPARE:
- case CPU_DOWN_PREPARE_FROZEN:
- cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu));
- break;
- case CPU_DOWN_FAILED:
- case CPU_DOWN_FAILED_FROZEN:
- break;
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- refresh_zone_stat_thresholds();
- vmstat_cpu_dead(cpu_to_node(cpu));
- break;
- default:
- break;
- }
- return NOTIFY_OK;
-}
-
-static struct notifier_block vmstat_notifier =
- { &vmstat_cpuup_callback, NULL, 0 };
#endif
static int __init setup_vmstat(void)
{
#ifdef CONFIG_SMP
- cpu_notifier_register_begin();
- __register_cpu_notifier(&vmstat_notifier);
+ int ret;
+
+ ret = cpuhp_setup_state_nocalls(CPUHP_MM_VMSTAT_DEAD, "mm/vmstat:dead",
+ NULL, vmstat_cpu_dead);
+ if (ret < 0)
+ pr_err("vmstat: failed to register 'dead' hotplug state\n");
+
+ ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "mm/vmstat:online",
+ vmstat_cpu_online,
+ vmstat_cpu_down_prep);
+ if (ret < 0)
+ pr_err("vmstat: failed to register 'online' hotplug state\n");
+
+ get_online_cpus();
init_cpu_node_state();
+ put_online_cpus();
start_shepherd_timer();
- cpu_notifier_register_done();
#endif
#ifdef CONFIG_PROC_FS
proc_create("buddyinfo", S_IRUGO, NULL, &fragmentation_file_operations);
--
2.10.2
