Re: [Qemu-devel] [PATCH] Revert "icount: remove obsolete warp call"

[Pavel Dovgalyuk]

> From: Paolo Bonzini [mailto:address@hidden
> QEMU running with options "-icount,sleep=off -rtc clock=vm" doesn't
> execute emulation at maximum possible speed.
> Target virtual clock may run faster or slower than realtime clock by N
> times, where N value depends on various unrelated conditions (i.e. random
> from the user point of view), or possibly the target hangs completely.
> Bisection shows commit 281b2201e4 ("icount: remove obsolete warp call",
> 2016-03-15) to be the culprit, revert it.
> 
> Suggested-by: Artem Pisarenko <address@hidden>
> Signed-off-by: Paolo Bonzini <address@hidden>
> ---
>  cpus.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/cpus.c b/cpus.c
> index 361678e459..2872e7e37c 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -1224,6 +1224,10 @@ static void qemu_tcg_rr_wait_io_event(CPUState *cpu)
>  {
>      while (all_cpu_threads_idle()) {
>          stop_tcg_kick_timer();
> +
> +        /* Start accounting real time to the virtual clock if the CPUs
> +           are idle.  */
> +        qemu_clock_warp(QEMU_CLOCK_VIRTUAL);

Can't apply, because this function does not exist anymore.

>          qemu_cond_wait(cpu->halt_cond, &qemu_global_mutex);
>      }
> 
> --
> 2.17.1



Pavel Dovgalyuk