Hi,
Recently I'm working to enable Qemu icount mode with TCG, with source code
review I found that Qemu can give deterministic execution for guest code
timeout. But for exact time point for guest OS, I have a question:
For armv7m_systick.c example, guest OS will use systick_read which will call "t
= qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); " to calculate his exact time point,
and qemu_clock_get_ns will use qemu_icount. But from qemu_tcg_rr_cpu_thread_fn
{ prepare_icount_for_run(cpu); r = tcg_cpu_exec(cpu);
process_icount_data(cpu);}, we know qemu just update qemu_icount value after
tcg_cpu_exec, so for each tcg_cpu_exec execution there is the same qemu_icount
value, and then guest code will get the same time point for that one tcg
execution. Can someone confirm that?
Thanks
