Re: [PATCH 00/33] hw/cpu/arm: Remove one use of qemu_get_cpu() in A7/A15 MPCore priv

[Philippe Mathieu-Daudé]

Hi Cédric,

On 2/1/24 15:55, Cédric Le Goater wrote:
> On 12/12/23 17:29, Philippe Mathieu-Daudé wrote:
> > Hi,
> >
> > When a MPCore cluster is used, the Cortex-A cores belong the the
> > cluster container, not to the board/soc layer. This series move
> > the creation of vCPUs to the MPCore private container.
> >
> > Doing so we consolidate the QOM model, moving common code in a
> > central place (abstract MPCore parent).
>
> Changing the QOM hierarchy has an impact on the state of the machine
> and some fixups are then required to maintain migration compatibility.
> This can become a real headache for KVM machines like virt for which
> migration compatibility is a feature, less for emulated ones.

All changes are either moving properties (which are not migrated)
or moving non-migrated QOM members (i.e. pointers of ARMCPU, which
is still migrated elsewhere). So I don't see any obvious migration
problem, but I might be missing something, so I Cc'ed Juan :>

> I don't have a good solution to propose to overcome this problem :/
>
> C.
>
>
> > This eventually allow removing one qemu_get_cpu() use, which we
> > want to remove in heterogeneous machines (machines using MPCore
> > are candidate for heterogeneous emulation).


> >   include/hw/arm/aspeed_soc.h    |   5 +-
> >   include/hw/arm/boot.h          |   4 +-
> >   include/hw/arm/exynos4210.h    |   6 +-
> >   include/hw/arm/fsl-imx6.h      |   6 +-
> >   include/hw/arm/fsl-imx6ul.h    |   8 +-
> >   include/hw/arm/fsl-imx7.h      |   8 +-
> >   include/hw/arm/npcm7xx.h       |   3 +-
> >   include/hw/cpu/a15mpcore.h     |  44 -------
> >   include/hw/cpu/a9mpcore.h      |  39 -------
> >   include/hw/cpu/cortex_mpcore.h | 135 ++++++++++++++++++++++