Re: [Qemu-devel] interrupt handling in qemu

[Lluís Vilanova]

Xin Tong writes:

> My main concern here is not how timely the interrupts can be handled,
> i am more interested in reducing the number of TB enters/exits due to
> interrupt. Returning to qemu mainloop requires saving and restoring
> register contexts which are expensive, what i am thinking is that can
> we check and handle interrupts every few TBs executed. But the
> drawback is that I do not know how many TBs would be a good number
> such that the interrupts do not get delayed too much.

I think a maximum amount of guest time for which interrupts can be delayed would
provide a better response (maybe together with a maximum number of delayed
interrupts).

For that you could program a "special" timer that forces a return-from-guest,
whatever the mechanism. But I'm sure that's going to make the system slower than
just checking every fixed number of TBs.


Lluis

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