Re: [Xen-devel] [PATCH 06/14] xen: arm: precalculate VTTBR_EL2 for a domain when setting up its p2m

[Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>]

On Tue, 12 Mar 2013, Ian Campbell wrote:
> From: Ian Campbell <ian.campbell@xxxxxxxxxx>
> 
> Mostly just to help with upcoming vcpu_show_registers changes.
> 
> Signed-off-by: Ian Campbell <ijc@xxxxxxxxxxxxxx>

Acked-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>


>  xen/arch/arm/p2m.c           |   16 +++++++++-------
>  xen/include/asm-arm/domain.h |    3 +++
>  2 files changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
> index 1e8c8b4..175216c 100644
> --- a/xen/arch/arm/p2m.c
> +++ b/xen/arch/arm/p2m.c
> @@ -23,13 +23,10 @@ void dump_p2m_lookup(struct domain *d, paddr_t addr)
>  
>  void p2m_load_VTTBR(struct domain *d)
>  {
> -    struct p2m_domain *p2m = &d->arch.p2m;
> -    paddr_t maddr = page_to_maddr(p2m->first_level);
> -    uint64_t vttbr = maddr;
> -
> -    vttbr |= ((uint64_t)p2m->vmid&0xff)<<48;
> -
> -    WRITE_SYSREG64(vttbr, VTTBR_EL2);
> +    if ( is_idle_domain(d) )
> +        return;
> +    BUG_ON(!d->arch.vttbr);
> +    WRITE_SYSREG64(d->arch.vttbr, VTTBR_EL2);
>      isb(); /* Ensure update is visible */
>  }
>  
> @@ -300,6 +297,9 @@ int p2m_alloc_table(struct domain *d)
>  
>      p2m->first_level = page;
>  
> +    d->arch.vttbr = page_to_maddr(p2m->first_level)
> +        | ((uint64_t)p2m->vmid&0xff)<<48;
> +
>      spin_unlock(&p2m->lock);
>  
>      return 0;
> @@ -331,6 +331,8 @@ int p2m_init(struct domain *d)
>      /* Zero is reserved */
>      p2m->vmid = d->domain_id + 1;
>  
> +    d->arch.vttbr = 0;
> +
>      p2m->first_level = NULL;
>  
>      return 0;
> diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
> index bf9caff..3da9163 100644
> --- a/xen/include/asm-arm/domain.h
> +++ b/xen/include/asm-arm/domain.h
> @@ -53,7 +53,10 @@ struct arch_domain
>      enum domain_type type;
>  #endif
>  
> +    /* Virtual MMU */
>      struct p2m_domain p2m;
> +    uint64_t vttbr;
> +
>      struct hvm_domain hvm_domain;
>      xen_pfn_t *grant_table_gpfn;
>  
> -- 
> 1.7.10.4
> 

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel