Re: [PATCH 36/37] xen/arm: Provide Kconfig options for Arm to enable NUMA

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Thu, 23 Sep 2021, Wei Chen wrote:
> Arm platforms support both ACPI and device tree. We don't
> want users to select device tree NUMA or ACPI NUMA manually.
> We hope usrs can just enable NUMA for Arm, and device tree
          ^ users

> NUMA and ACPI NUMA can be selected depends on device tree
> feature and ACPI feature status automatically. In this case,
> these two kinds of NUMA support code can be co-exist in one
> Xen binary. Xen can check feature flags to decide using
> device tree or ACPI as NUMA based firmware.
> 
> So in this patch, we introduce a generic option:
> CONFIG_ARM_NUMA for user to enable NUMA for Arm.
                      ^ users

> And one CONFIG_DEVICE_TREE_NUMA option for ARM_NUMA
> to select when HAS_DEVICE_TREE option is enabled.
> Once when ACPI NUMA for Arm is supported, ACPI_NUMA
> can be selected here too.
> 
> Signed-off-by: Wei Chen <wei.chen@xxxxxxx>
> ---
>  xen/arch/arm/Kconfig | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig
> index 865ad83a89..ded94ebd37 100644
> --- a/xen/arch/arm/Kconfig
> +++ b/xen/arch/arm/Kconfig
> @@ -34,6 +34,17 @@ config ACPI
>         Advanced Configuration and Power Interface (ACPI) support for Xen is
>         an alternative to device tree on ARM64.
>  
> + config DEVICE_TREE_NUMA
> +     def_bool n
> +     select NUMA
> +
> +config ARM_NUMA
> +     bool "Arm NUMA (Non-Uniform Memory Access) Support (UNSUPPORTED)" if 
> UNSUPPORTED
> +     select DEVICE_TREE_NUMA if HAS_DEVICE_TREE

Should it be: depends on HAS_DEVICE_TREE ?
(And eventually depends on HAS_DEVICE_TREE || ACPI)


> +     ---help---
> +
> +       Enable Non-Uniform Memory Access (NUMA) for Arm architecutres
                                                      ^ architectures


> +
>  config GICV3
>       bool "GICv3 driver"
>       depends on ARM_64 && !NEW_VGIC
> -- 
> 2.25.1
>