In the controller, QEMUTimer will be used in the implementation of timer
simulation.

I wrote an auto-loading timer with a period of 1ms and the clock source
used is QEMU_CLOCK_VIRTUAL. But it doesn't seem to be very accurate,
because the actual time after I accumulated it to 500 times took about
700ms.

I think qemu's code will consume some time, is it true?


thank you ~