Re: [RFC v1 00/38] arm cleanup experiment for kvm-only build

[Alex Bennée]

Claudio Fontana <cfontana@suse.de> writes:

> On 2/23/21 10:18 AM, Philippe Mathieu-Daudé wrote:
>> On 2/22/21 8:00 PM, Alex Bennée wrote:
>>>
>>> Claudio Fontana <cfontana@suse.de> writes:
>>>
>>>> Hi all,
>>>>
>>>> this is an experiment, a cleanup based on and requiring the series
>>>> "i386 cleanup PART 2":
>>>>
>>>> https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg05935.html
>>>>
>>>> The goal is to split the code between TCG-only and non-TCG code,
>>>> fixing the KVM-only build (configure --disable-tcg),
>>>>
>>>> and laying the ground for further cleanups and the use of the
>>>> new accel objects in the hierarchy to specialize the cpu
>>>> according to the accelerator.
>>>>
>>>> This is known to be an early state, with probably a lot of work
>>>> still needed.
>>>
>>> Well early work is looking pretty good:
>>>
>>>   18:59:22 [alex@idun:~/l/q/b/default] review/arm-cleanup-rfc1|… ± ls -lh 
>>> qemu-system-aarch64
>>>   -rwxr-xr-x 1 alex alex 107M Feb 22 18:08 qemu-system-aarch64*
>>>   18:59:29 [alex@idun:~/l/q/b/default] review/arm-cleanup-rfc1|… ± ls -lh 
>>> ../disable.tcg/qemu-system-aarch64
>>>   -rwxr-xr-x 1 alex alex 76M Feb 22 17:47 
>>> ../disable.tcg/qemu-system-aarch64*
>> 
>> :~)
>> 
>>>
>>> and I've tested the KVM side works well enough with a basic image.
>> 
>> 
>
> I am working on the next version, one thing I noticed among others as I get 
> close to the v2,
> is the fact that tests/ for arm require tcg in many cases.

I think in a lot of cases they are historical because developers
generally weren't running on native hardware. That said off the top of
my head:

  tests/tcg - linux-user, so implies TCG
  tests/tcg/system - use semihosting (at least for arm/aarch64) - which implies 
TCG
  tests/acceptance/[replay_kernel/reverse_debugging/tcg_plugins] - all need TCG 
features

I don't think there is any reason the others can't run with KVM - and
probably should on real hardware.

>
> So there is even more cleanup needed to discern which are actually tcg-only, 
> and how to tweak the others into working also with only kvm available..
>
> Ciao,
>
> Claudio


-- 
Alex Bennée