Re: [RFC 1/4] xen/arm64: Map the redistributor region by max_vcpus of domU danamically

[Julien Grall <julien.grall@citrix.com>]

Hi Chen,

On 14/05/15 15:14, Chen Baozi wrote:
> diff --git a/xen/common/domctl.c b/xen/common/domctl.c
> index e571e76..43b9f79 100644
> --- a/xen/common/domctl.c
> +++ b/xen/common/domctl.c
> @@ -33,6 +33,11 @@
>  #include <public/domctl.h>
>  #include <xsm/xsm.h>
>  
> +#ifdef CONFIG_ARM_64
> +#include <asm/gic.h>
> +#include <asm/vgic.h>
> +#endif
> +
>  static DEFINE_SPINLOCK(domctl_lock);
>  DEFINE_SPINLOCK(vcpu_alloc_lock);
>  
> @@ -680,6 +685,11 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
>              d->max_vcpus = max;
>          }
>  
> +#ifdef CONFIG_ARM_64
> +        if (!is_hardware_domain(d) && d->arch.vgic.version == GIC_V3)
> +            vgic_v3_rdist_map(d);
> +#endif

That is very hackish. It's common with other architecture and we are
trying to be vgic agnostic in general. A vGIC callback would be more
suitable.

Although, as said on the cover letter. It's not necessary to allocate
dynamically. We can expand the current region to support up to 16/128 vCPUs.

Regards,

-- 
Julien Grall