Re: [Qemu-devel] [PATCH v2 1/3] pc-dimm: add a function to calculate VM's current RAM size

[zhanghailiang <zhang.zhanghailiang@huawei.com>]

On 2014/11/19 18:32, Michael S. Tsirkin wrote:
> On Mon, Nov 17, 2014 at 01:11:08PM +0800, zhanghailiang wrote:
>> The global parameter 'ram_size' does not take into account
>> the hotplugged memory.
>>
>> In some codes, we use 'ram_size' as current VM's real RAM size,
>> which is not correct.
>>
>> Add function 'get_current_ram_size' to calculate VM's current RAM size,
>> it will enumerate present memory devices and also plus ram_size.
>>
>> Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
>
>
> This affects QMP right?

Yes, will affect the results of balloon commands ;)

> Cc Luiz.
>
>
>> ---
>>   hw/mem/pc-dimm.c                | 26 ++++++++++++++++++++++++++
>>   include/exec/cpu-common.h       |  1 +
>>   stubs/qmp_pc_dimm_device_list.c |  5 +++++
>>   3 files changed, 32 insertions(+)
>>
>> diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
>> index a800ea7..38465d0 100644
>> --- a/hw/mem/pc-dimm.c
>> +++ b/hw/mem/pc-dimm.c
>> @@ -62,6 +62,32 @@ int qmp_pc_dimm_device_list(Object *obj, void *opaque)
>>       return 0;
>>   }
>>
>> +ram_addr_t get_current_ram_size(void)
>> +{
>> +    MemoryDeviceInfoList *info_list = NULL;
>> +    MemoryDeviceInfoList **prev = &info_list;
>> +    MemoryDeviceInfoList *info;
>> +    ram_addr_t size = ram_size;
>> +
>> +    qmp_pc_dimm_device_list(qdev_get_machine(), &prev);
>> +    for (info = info_list; info; info = info->next) {
>> +        MemoryDeviceInfo *value = info->value;
>> +
>> +        if (value) {
>> +            switch (value->kind) {
>> +            case MEMORY_DEVICE_INFO_KIND_DIMM:
>> +                size += value->dimm->size;
>> +                break;
>> +            default:
>> +                break;
>> +            }
>> +        }
>> +    }
>> +    qapi_free_MemoryDeviceInfoList(info_list);
>> +
>> +    return size;
>> +}
>> +
>>   static int pc_dimm_slot2bitmap(Object *obj, void *opaque)
>>   {
>>       unsigned long *bitmap = opaque;
>> diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
>> index 427b851..fcc3162 100644
>> --- a/include/exec/cpu-common.h
>> +++ b/include/exec/cpu-common.h
>> @@ -52,6 +52,7 @@ typedef uintptr_t ram_addr_t;
>>   #endif
>>
>>   extern ram_addr_t ram_size;
>> +ram_addr_t get_current_ram_size(void);
>>
>>   /* memory API */
>>
>> diff --git a/stubs/qmp_pc_dimm_device_list.c b/stubs/qmp_pc_dimm_device_list.c
>> index 5cb220c..b584bd8 100644
>> --- a/stubs/qmp_pc_dimm_device_list.c
>> +++ b/stubs/qmp_pc_dimm_device_list.c
>> @@ -5,3 +5,8 @@ int qmp_pc_dimm_device_list(Object *obj, void *opaque)
>>   {
>>      return 0;
>>   }
>> +
>> +ram_addr_t get_current_ram_size(void)
>> +{
>> +    return ram_size;
>> +}
>> --
>> 1.7.12.4
>>
>
> .
>