Re: [Qemu-devel] [PATCH v6 11/18] hw/arm/virt: Add memory hotplug framework

[David Hildenbrand <david@redhat.com>]

On 05.02.19 18:32, Eric Auger wrote:
> This patch adds the the memory hot-plug/hot-unplug infrastructure
> in machvirt. It is still not enabled as no device memory is allocated.
> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
> Signed-off-by: Kwangwoo Lee <kwangwoo.lee@sk.com>
> 
> ---
> v4 -> v5:
> - change in pc_dimm_pre_plug signature
> - CONFIG_MEM_HOTPLUG replaced by CONFIG_MEM_DEVICE and CONFIG_DIMM
> 
> v3 -> v4:
> - check the memory device is not hotplugged
> 
> v2 -> v3:
> - change in pc_dimm_plug()'s signature
> - add pc_dimm_pre_plug call
> 
> v1 -> v2:
> - s/virt_dimm_plug|unplug/virt_memory_plug|unplug
> - s/pc_dimm_memory_plug/pc_dimm_plug
> - reworded title and commit message
> - added pre_plug cb
> - don't handle get_memory_region failure anymore
> ---
>  default-configs/arm-softmmu.mak |  2 ++
>  hw/arm/virt.c                   | 64 ++++++++++++++++++++++++++++++++-
>  2 files changed, 65 insertions(+), 1 deletion(-)
> 
> diff --git a/default-configs/arm-softmmu.mak b/default-configs/arm-softmmu.mak
> index be88870799..dc4624794f 100644
> --- a/default-configs/arm-softmmu.mak
> +++ b/default-configs/arm-softmmu.mak
> @@ -160,3 +160,5 @@ CONFIG_PCI_DESIGNWARE=y
>  CONFIG_STRONGARM=y
>  CONFIG_HIGHBANK=y
>  CONFIG_MUSICPAL=y
> +CONFIG_MEM_DEVICE=y
> +CONFIG_DIMM=y
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index f01886da22..783468ba77 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -59,6 +59,8 @@
>  #include "qapi/visitor.h"
>  #include "standard-headers/linux/input.h"
>  #include "hw/arm/smmuv3.h"
> +#include "hw/mem/pc-dimm.h"
> +#include "hw/mem/nvdimm.h"
>  
>  #define DEFINE_VIRT_MACHINE_LATEST(major, minor, latest) \
>      static void virt_##major##_##minor##_class_init(ObjectClass *oc, \
> @@ -1763,6 +1765,49 @@ static const CPUArchIdList *virt_possible_cpu_arch_ids(MachineState *ms)
>      return ms->possible_cpus;
>  }
>  
> +static void virt_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
> +                                 Error **errp)
> +{
> +    const bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM);
> +
> +    if (dev->hotplugged) {
> +        error_setg(errp, "memory hotplug is not supported");
> +    }
> +
> +    if (is_nvdimm) {
> +        error_setg(errp, "nvdimm is not yet supported");
> +        return;
> +    }
> +
> +    pc_dimm_pre_plug(PC_DIMM(dev), MACHINE(hotplug_dev), NULL, errp);
> +}
> +
> +static void virt_memory_plug(HotplugHandler *hotplug_dev,
> +                             DeviceState *dev, Error **errp)
> +{
> +    VirtMachineState *vms = VIRT_MACHINE(hotplug_dev);
> +    Error *local_err = NULL;
> +
> +    pc_dimm_plug(PC_DIMM(dev), MACHINE(vms), &local_err);
> +
> +    error_propagate(errp, local_err);
> +}
> +
> +static void virt_memory_unplug(HotplugHandler *hotplug_dev,
> +                               DeviceState *dev, Error **errp)
> +{
> +    pc_dimm_unplug(PC_DIMM(dev), MACHINE(hotplug_dev));
> +    object_unparent(OBJECT(dev));

Please note that this will soon change with

[PATCH RFCv2 0/9] qdev: Hotplug handler chaining + virtio-pmem

What you'll have to do then is to replace the object_unparent by a

object_property_set_bool(OBJECT(dev), false, "realized", NULL);


-- 

Thanks,

David / dhildenb