[CRIU] [PATCH v2 3/3] aio: Restore aio ring content

[Pavel Emelyanov]

On 03/21/2016 03:02 PM, Kirill Tkhai wrote:
> 
> 
> On 21.03.2016 13:15, Pavel Emelyanov wrote:
>> On 03/21/2016 01:10 PM, Kirill Tkhai wrote:
>>
>>>>> I'm going to add plugin to parasite_check_aios(), and to wait inflight requests
>>>>> from there.
>>>>>  
>>>>>> Anyway, I don't think treating aio ring buffer as regular anonymous memory
>>>>>> is good idea.
>>>>>
>>>>> What do you suggest? Add vma_entry_is_private(entry) | vma_entry_is(entry, VMA_AREA_AIORING)
>>>>> every place we used it?
>>>>
>>>> Not every. My current opinion is that soft-dirty tracking should NOT
>>>> be done for AIO rings.
>>>
>>> So, if we skip AIO on pre-dump, but we will dump it like any other private memory,
>>> is this OK for you?
>>
>> I tend to think it's not, since these are objects with structure. However
>> I don't have string arguments against dumping them as raw blobs _provided_
>> we check for ring head magic beforehand.
> 
> I don't completely understand you. What is dumping as raw blobs, but not as like memory?

By "as raw blobs" I mean just read the contents of the memory byte-by-byte w/o
understanding its structure.

> Checking of ring head magic make a sense at a restore, but which way should it be used
> at dump?

I'd say the same -- check magic and go ahead and read ring memory contents starting
from the events array. Reading the header as memory doesn't make sense from my pov.

-- Pavel