{
int cpu, node;
- hotcpu_notifier(memcg_cpu_hotplug_callback, 0);
+ #ifndef CONFIG_SLOB
+ /*
+ * Kmem cache creation is mostly done with the slab_mutex held,
+ * so use a special workqueue to avoid stalling all worker
+ * threads in case lots of cgroups are created simultaneously.
+ */
+ memcg_kmem_cache_create_wq =
+ alloc_ordered_workqueue("memcg_kmem_cache_create", 0);
+ BUG_ON(!memcg_kmem_cache_create_wq);
+ #endif
+
+ cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL,
+ memcg_hotplug_cpu_dead);
for_each_possible_cpu(cpu)
INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work,