[Qemu-devel] Re: [PATCH] fix halt emulation with icount and CONFIG_IOTHREAD

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2011-02-15 18:54, Marcelo Tosatti wrote:
> 
> Note: to be applied to uq/master.
> 
> In icount mode, halt emulation should take into account the nearest event when sleeping.
> 
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
> Reported-and-tested-by: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
> 
> diff --git a/cpus.c b/cpus.c
> index 468544c..21c3eba 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -770,7 +770,7 @@ static void qemu_tcg_wait_io_event(void)
>      CPUState *env;
>  
>      while (all_cpu_threads_idle()) {
> -        qemu_cond_timedwait(tcg_halt_cond, &qemu_global_mutex, 1000);
> +        qemu_cond_timedwait(tcg_halt_cond, &qemu_global_mutex, qemu_calculate_timeout());

checkpatch.pl would complain here.

More important: Paolo was proposing patches to eliminate all those fishy
cond_wait timeouts. That's probably the better way to go. The timeouts
only paper over missing signaling.

>      }
>  
>      qemu_mutex_unlock(&qemu_global_mutex);
> diff --git a/vl.c b/vl.c
> index b436952..8ba7e9d 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -1335,7 +1335,7 @@ void main_loop_wait(int nonblocking)
>      if (nonblocking)
>          timeout = 0;
>      else {
> -        timeout = qemu_calculate_timeout();
> +        timeout = 1000;
>          qemu_bh_update_timeout(&timeout);
>      }
>  

Isn't this path also relevant for !IOTHREAD? What's the impact of this
change for that configuration?

Jan

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