[PATCH v2, part3 08/12] mm: use a dedicated lock to protect totalram_pages and zone->managed_pages

Currently lock_memory_hotplug()/unlock_memory_hotplug() are used to protect totalram_pages and zone->managed_pages. Other than the memory hotplug driver, totalram_pages and zone->managed_pages may be modified by Xen balloon, virtio_balloon etc at runtime. For those case, memory hotplug lock is a

[PATCH v2, part3 08/12] mm: use a dedicated lock to protect totalram_pages and zone-managed_pages

Currently lock_memory_hotplug()/unlock_memory_hotplug() are used to protect totalram_pages and zone-managed_pages. Other than the memory hotplug driver, totalram_pages and zone-managed_pages may be modified by Xen balloon, virtio_balloon etc at runtime. For those case, memory hotplug lock is a