On 2012-07-26 13:16, Juan Quintela wrote:
> Jan Kiszka <jan.kis...@siemens.com> wrote:
>> On 2012-07-24 20:36, Juan Quintela wrote:
>>> Hi
>
>>> Appart of the review:
>>> - Are there any locking issues that I have missed (I guess so)
>>> - stop all cpus correctly. vm_stop should be called from the iothread,
>>> I use the trick of using a bottom half to get that working correctly.
>>> but this _implementation_ is ugly as hell. Is there an easy way
>>> of doing it?
>>
>> vm_stop is prepared to be called from vcpu context as well. I'm not sure
>> right now if we actually do, but the code is there.
>
> But this is a migation_thread (i.e. neither iothread of vcpu), and we
> need to wait for vm_stop to finish. My reading is that in vcpu context,
> we just ask the iothread to stop all cpus.
>
> void vm_stop(RunState state)
> {
> if (!qemu_thread_is_self(&io_thread)) {
> qemu_system_vmstop_request(state);
> /*
> * FIXME: should not return to device code in case
> * vm_stop() has been requested.
> */
> cpu_stop_current();
> return;
> }
> do_vm_stop(state);
> }
>
> Or I am reading it wrong?
Ah, indeed. Did you try top make this service ready for such a use case
(sorry, didn't look at the code yet)? Something like issuing
qemu_system_vmstop_request and then resuming the with the next step on a
vmstate change notification?
Jan
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