Re: [PATCH-for-10.1 4/4] tcg: Convert TARGET_SUPPORTS_MTTCG to TCGCPUOps::mttcg_supported field

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 23/3/25 23:13, BALATON Zoltan wrote:
> On Sun, 23 Mar 2025, Philippe Mathieu-Daudé wrote:
>> On 23/3/25 20:07, Richard Henderson wrote:
>>>> diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
>>>> index 28fbbb8d3c1..ed79cc1a6b7 100644
>>>> --- a/target/ppc/cpu_init.c
>>>> +++ b/target/ppc/cpu_init.c
>>>> @@ -7490,6 +7490,7 @@ static const TCGCPUOps ppc_tcg_ops = {
>>>>     .translate_code = ppc_translate_code,
>>>>     .restore_state_to_opc = ppc_restore_state_to_opc,
>>>> +  .mttcg_supported = TARGET_LONG_BITS == 64,
>>>>     .guest_default_memory_order = 0,
>>>
>>> Similarly.  I'd be surprised if ppc32 can't use mttcg, really.
>>
>> Per Cédric on IRC our ppc32 implementations are single core,
>> so never tested for mttcg.
> 
> We're just trying to implement more CPUs for G4 mac99 and tested it with 
> -smp 2 and it seems to generally work but we need to implement more of 
> the Mac hardware for this but we could already run Mac OS X with two 
> CPUs and mttcg and Linux too if we add a delay on boot when second CPU 
> is started (it may need implementing timebase control as done on the G4 
> Mac to avoid that but if it gets past that it seems to work). So please 
> leave this enabled. Not tested does not mean it does not work so only 
> disable if there's a known problem.

This patch aims to be a no-op (no logical change), so does not disable
it since it is already disabled:

$ git grep TARGET_SUPPORTS_MTTCG master -- configs/targets/ppc-softmmu.mak
$

Enabling would come as a distinct patch by someone with good
knowledge of the architecture, so not me :)