Re: [Qemu-ppc] [Qemu-devel] [QEMU PATCH v5 4/6] migration: migrate QTAILQ

[Jianjun Duan]

On 10/07/2016 09:32 AM, Paolo Bonzini wrote:
> 
> 
> On 07/10/2016 18:31, Jianjun Duan wrote:
>>
>>
>> On 10/07/2016 07:34 AM, Dr. David Alan Gilbert wrote:
>>> * Paolo Bonzini (address@hidden) wrote:
>>>>
>>>>
>>>> On 06/10/2016 21:01, Dr. David Alan Gilbert wrote:
>>>>>>>> +                } else if (field->flags & VMS_LINKED) {
>>>>>>>> +                    ret = field->info->get(f, addr, size, field);
>>>>>>>>                  } else {
>>>>>>>>                      ret = field->info->get(f, addr, size, NULL);
>>>>>>>>  
>>>>>>>> @@ -193,6 +197,8 @@ static const char 
>>>>>>>> *vmfield_get_type_name(VMStateField *field)
>>>>>>>>  
>>>>>>>>      if (field->flags & VMS_STRUCT) {
>>>>>>>>          type = "struct";
>>>>>>>> +    } else if (field->flags & VMS_LINKED) {
>>>>>>>> +        type = "linked";
>>>>>>>>      } else if (field->info->name) {
>>>>>>>>          type = field->info->name;
>>>>>>>>      }
>>>>>>>> @@ -327,6 +333,8 @@ void vmstate_save_state(QEMUFile *f, const 
>>>>>>>> VMStateDescription *vmsd,
>>>>>>>>                  }
>>>>>>>>                  if (field->flags & VMS_STRUCT) {
>>>>>>>>                      vmstate_save_state(f, field->vmsd, addr, 
>>>>>>>> vmdesc_loop);
>>>>>>>> +                } else if  (field->flags & VMS_LINKED) {
>>>>>>>> +                    field->info->put(f, addr, size, field, 
>>>>>>>> vmdesc_loop);
>>>>>>>>                  } else {
>>>>>>>>                      field->info->put(f, addr, size, NULL, NULL);
>>>>>>>>                  }
>>>>
>>>> Is VMS_LINKED needed at all, since the fields are unused for every
>>>> VMStateInfo except qtailq?
>>>
>>> No, I think you could easily drop the VMS_LINKED and just always pass them 
>>> in.
>>
>> It is needed if we want to use vmdesc_loop.
> 
> Just always pass it in, can't you?
> 
Could that lead to repetition of array elements? I know it depends on
individual put details.

Thanks,
Jianjun
> Paolo
>