Re: [virtio-dev] Re: [PATCH] virtio-balloon: Disable free page hinting/reporting if page poison is disabled

[David Hildenbrand <david@redhat.com>]

On 17.04.20 12:29, Michael S. Tsirkin wrote:
> On Fri, Apr 17, 2020 at 12:26:24PM +0200, David Hildenbrand wrote:
>> On 17.04.20 12:19, Michael S. Tsirkin wrote:
>>> On Fri, Apr 17, 2020 at 12:09:38PM +0200, David Hildenbrand wrote:
>>>>  > What do you call "hinting ends" though? The fact we put
>>>>> a page in the VQ is not a guarantee that it's been consumed
>>>>> by the hypervisor.
>>>>>
>>>>
>>>> I'd say hinting ends once the hypervisor sets FREE_PAGE_REPORT_S_DONE.
>>>
>>> Can't find that one anywhere. what did I miss?
>>
>> Sorry, the QEMU implementation is confusing. FREE_PAGE_REPORT_S_DONE is
>> translated to VIRTIO_BALLOON_CMD_ID_DONE
> 
> Well VIRTIO_BALLOON_CMD_ID_DONE just means "don't give me any
> more hints, I finished migration".
> Guest will stop hinting even without that once it scans all
> free memory.

Yeah, that's the end of the whole process where you can be sure the host
processed all requests definetly.

-- 
Thanks,

David / dhildenb