On 01/12/2012 11:58 AM, Stefan Hajnoczi wrote:
> This is something I'm looking at right now and will probably want to
> discuss with Paolo.
>
> In a coroutine we're probably using a main loop and timers should be
> available there.  In general, the problem we're starting to see is
> that some block layer features are using timers (I/O throttling, QED
> deferred dirty bit clearing, image streaming).  The question is do we
> isolate this functionality so it is unavailable from a qemu-tool world
> when there's no main loop, or do we move everything into a main loop?

Yes, I would move things into a main loop just like qemu-nbd does.  I 
even had some prototype patches for it.  The qemu-img part is broken 
because it uses callbacks that haven't been made asynchronous yet; the 
one for qemu-io should be okay modulo some more testing.

Paolo