Well personally I prefer the type thing and I don't see much difference
at userspace level anyway. But I am not this kind of hyperspace
architect guy. So, since there is no consensus here, I would say let's
wait for formal reviews of our maintainers and I will align.

 Hah, okay... Don't take it for too much. Anyway your word weighs much more than my one...

hope this eventually works with
ITS ;-)

 You know... There are actually problems with irqfd. However i'm not sure whether they are result of
some bug or of poorly made vGIC CPU interface software emulation. I don't have hardware with working
vGICv3 here. With GICv2m everything is fine, but code path is quite different, and LPI != SPI.
 This is further overcomplicated by the fact that as soon as i start up the profiler, the problem
goes away. Looks like increased number of context switches have impact.
 Actually, the problem is very poor vhost-net throughput, which jumps up when i start the profiler
and goes back down when i stop it. Just to note...
 I'm off since now for a small vacation, will be back on monday or tuesday. See you guys!

Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia