On 23/09/19 13:30, Markus Armbruster wrote:
> -accel is yet another convenience option. We have so many of them. I
> dislike the complexity they add to the CLI. Here's how this one got in:
>
> commit 8d4e9146b3568022ea5730d92841345d41275d66
> Author: KONRAD Frederic <[email protected]>
> Date: Thu Feb 23 18:29:08 2017 +0000
>
> tcg: add options for enabling MTTCG
>
> We know there will be cases where MTTCG won't work until additional work
> is done in the front/back ends to support. It will however be useful to
> be able to turn it on.
>
> As a result MTTCG will default to off unless the combination is
> supported. However the user can turn it on for the sake of testing.
>
> Signed-off-by: KONRAD Frederic <[email protected]>
> [AJB: move to -accel tcg,thread=multi|single, defaults]
> Signed-off-by: Alex Bennée <[email protected]>
> Reviewed-by: Richard Henderson <[email protected]>
>
> Not a peep on why the existing options are so insufficient we must have
> another one.
>
> Our CLI will remain the steaming mess it has become until we reform the
> habits that got us there.
-accel's accel suboption is currently defined as a convenience option,
but it shouldn't be. It's the older "-M accel=foo:bar" that should
become "-accel foo -accel bar" and -accel then is the preferred way.
The existing option "-M accel" was insufficient because it didn't allow
accelerator-specific suboptions; they were all over the place ("-machine
kernel_irqchip", "-tb-size", etc.) and indeed mostly in wrong places.
Paolo
