[Qemu-devel] Re: [PATCH 16/23] Port PCI Bus to VMState design

[Gerd Hoffmann <kraxel@redhat.com>]

On 08/21/09 11:04, Juan Quintela wrote:
> Gerd Hoffmann<kraxel@redhat.com>  wrote:
>> On 08/20/09 19:42, Juan Quintela wrote:
>>> This uses VARRAY and INT32_EQUAL values
>> This is one place where I would change the code to reduce load/save
>> complexity.
>>
>> Quick grep shows that the max value for bus->nirqs is
>> 32. s/*irq_count/irq_count[32]/ for PCIBus, drop dynamic allocation
>> and allways save/load 32 values.  INT32_EQUAL + VARRAY isn't needed
>> then.
>
> I agree to drop INT32_EQUAL, but maintain the VARRAY.
> VARRAY is nice if there is another field in the stuct that tolds you how
> many are used.

If you save all of them anyway you don't need that.
(but you still must save the bus->nirqs field obviously).

> If you change the 32 number, you just need to upgrade the version.
> Will do something like that.
>
> The reason that I don't want to send the whole thing is that there are
> times when we are sending tables that are empty (devices not being
> used).

I still would save it.  If you find a NULL pointer save a bunch of zeros 
instead.  Device state isn't that big, and I think it is good to have 
fixed-size sections.

cheers
   Gerd