Re: [PATCH v24 09/21] qapi/s390x/cpu topology: set-cpu-topology qmp command

[Thomas Huth]

On 26/09/2023 14.15, Nina Schoetterl-Glausch wrote:
> From: Pierre Morel <pmorel@linux.ibm.com>
>
> The modification of the CPU attributes are done through a monitor
> command.
>
> It allows to move the core inside the topology tree to optimize
> the cache usage in the case the host's hypervisor previously
> moved the CPU.
>
> The same command allows to modify the CPU attributes modifiers
> like polarization entitlement and the dedicated attribute to notify
> the guest if the host admin modified scheduling or dedication of a vCPU.
>
> With this knowledge the guest has the possibility to optimize the
> usage of the vCPUs.
>
> The command has a feature unstable for the moment.
>
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> Reviewed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
> Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
> Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
> ---
...
> +
> +void qmp_set_cpu_topology(uint16_t core,
> +                         bool has_socket, uint16_t socket,
> +                         bool has_book, uint16_t book,
> +                         bool has_drawer, uint16_t drawer,
> +                         bool has_entitlement, CpuS390Entitlement entitlement,
> +                         bool has_dedicated, bool dedicated,
> +                         Error **errp)

Nit: Indentation seems to be off by 1 space in the above lines.

 Thomas


> +{
> +    if (!s390_has_topology()) {
> +        error_setg(errp, "This machine doesn't support topology");
> +        return;
> +    }
> +
> +    s390_change_topology(core, has_socket, socket, has_book, book,
> +                         has_drawer, drawer, has_entitlement, entitlement,
> +                         has_dedicated, dedicated, errp);
> +}