Re: [PATCH RFC server v2 05/11] vfio-user: run vfio-user context

[John Levon]

On Wed, Sep 08, 2021 at 04:02:22PM +0100, Stefan Hajnoczi wrote:

> > We'd have to have a whole separate API to do that, so a separate thread 
> > seems a
> > better approach?
> 
> Whether to support non-blocking properly in libvfio-user is a decision
> for you. If libvfio-user doesn't support non-blocking, then QEMU should
> run a dedicated thread instead of the partially non-blocking approach in
> this patch.

Right, sure. At this point we don't have any plans to implement a separate async
API due to the amount of work involved. 

> A non-blocking approach is nice when there are many devices hosted in a
> single process or a lot of async replies (which requires extra thread
> synchronization with the blocking approach).

I suppose this would be more of a problem with devices where the I/O path has to
be handled via the socket.

regards
john