Re: [PATCH v4 07/12] x86: expose CBM length and COS number information

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 09/04/2015 10:18, Chao Peng wrote:
> General CAT information such as maximum COS and CBM length are exposed to
> user space by a SYSCTL hypercall, to help user space to construct the CBM.
>
> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

> ---
>  xen/arch/x86/psr.c          | 31 +++++++++++++++++++++++++++++++
>  xen/arch/x86/sysctl.c       | 18 ++++++++++++++++++
>  xen/include/asm-x86/psr.h   |  3 +++
>  xen/include/public/sysctl.h | 16 ++++++++++++++++
>  4 files changed, 68 insertions(+)
>
> diff --git a/xen/arch/x86/psr.c b/xen/arch/x86/psr.c
> index 51faa70..e390fd9 100644
> --- a/xen/arch/x86/psr.c
> +++ b/xen/arch/x86/psr.c
> @@ -221,6 +221,37 @@ void psr_ctxt_switch_to(struct domain *d)
>      }
>  }
>  
> +static int get_cat_socket_info(unsigned int socket,
> +                               struct psr_cat_socket_info **info)
> +{
> +    if ( !cat_socket_info )
> +        return -ENODEV;
> +
> +    if ( socket >= nr_sockets )
> +        return -EBADSLT;
> +
> +    if ( !cat_socket_info[socket].enabled )
> +        return -ENOENT;
> +
> +    *info = cat_socket_info + socket;
> +    return 0;
> +}
> +
> +int psr_get_cat_l3_info(unsigned int socket, uint32_t *cbm_len,
> +                        uint32_t *cos_max)
> +{
> +    struct psr_cat_socket_info *info;
> +    int ret = get_cat_socket_info(socket, &info);
> +
> +    if ( ret )
> +        return ret;
> +
> +    *cbm_len = info->cbm_len;
> +    *cos_max = info->cos_max;
> +
> +    return 0;
> +}
> +
>  /* Called with domain lock held, no psr specific lock needed */
>  static void psr_free_cos(struct domain *d)
>  {
> diff --git a/xen/arch/x86/sysctl.c b/xen/arch/x86/sysctl.c
> index 611a291..8a9e120 100644
> --- a/xen/arch/x86/sysctl.c
> +++ b/xen/arch/x86/sysctl.c
> @@ -171,6 +171,24 @@ long arch_do_sysctl(
>  
>          break;
>  
> +    case XEN_SYSCTL_psr_cat_op:
> +        switch ( sysctl->u.psr_cat_op.cmd )
> +        {
> +        case XEN_SYSCTL_PSR_CAT_get_l3_info:
> +            ret = psr_get_cat_l3_info(sysctl->u.psr_cat_op.target,
> +                                      &sysctl->u.psr_cat_op.u.l3_info.cbm_len,
> +                                      &sysctl->u.psr_cat_op.u.l3_info.cos_max);
> +
> +            if ( !ret && __copy_to_guest(u_sysctl, sysctl, 1) )
> +                ret = -EFAULT;
> +
> +            break;
> +        default:
> +            ret = -EOPNOTSUPP;
> +            break;
> +        }
> +        break;
> +
>      default:
>          ret = -ENOSYS;
>          break;
> diff --git a/xen/include/asm-x86/psr.h b/xen/include/asm-x86/psr.h
> index 45392bf..3a8a406 100644
> --- a/xen/include/asm-x86/psr.h
> +++ b/xen/include/asm-x86/psr.h
> @@ -52,6 +52,9 @@ void psr_free_rmid(struct domain *d);
>  
>  void psr_ctxt_switch_to(struct domain *d);
>  
> +int psr_get_cat_l3_info(unsigned int socket, uint32_t *cbm_len,
> +                        uint32_t *cos_max);
> +
>  int psr_domain_init(struct domain *d);
>  void psr_domain_free(struct domain *d);
>  
> diff --git a/xen/include/public/sysctl.h b/xen/include/public/sysctl.h
> index 8552dc6..91d90b8 100644
> --- a/xen/include/public/sysctl.h
> +++ b/xen/include/public/sysctl.h
> @@ -656,6 +656,20 @@ struct xen_sysctl_psr_cmt_op {
>  typedef struct xen_sysctl_psr_cmt_op xen_sysctl_psr_cmt_op_t;
>  DEFINE_XEN_GUEST_HANDLE(xen_sysctl_psr_cmt_op_t);
>  
> +#define XEN_SYSCTL_PSR_CAT_get_l3_info               0
> +struct xen_sysctl_psr_cat_op {
> +    uint32_t cmd;       /* IN: XEN_SYSCTL_PSR_CAT_* */
> +    uint32_t target;    /* IN: socket to be operated on */
> +    union {
> +        struct {
> +            uint32_t cbm_len;   /* OUT: CBM length */
> +            uint32_t cos_max;   /* OUT: Maximum COS */
> +        } l3_info;
> +    } u;
> +};
> +typedef struct xen_sysctl_psr_cat_op xen_sysctl_psr_cat_op_t;
> +DEFINE_XEN_GUEST_HANDLE(xen_sysctl_psr_cat_op_t);
> +
>  struct xen_sysctl {
>      uint32_t cmd;
>  #define XEN_SYSCTL_readconsole                    1
> @@ -678,6 +692,7 @@ struct xen_sysctl {
>  #define XEN_SYSCTL_scheduler_op                  19
>  #define XEN_SYSCTL_coverage_op                   20
>  #define XEN_SYSCTL_psr_cmt_op                    21
> +#define XEN_SYSCTL_psr_cat_op                    22
>      uint32_t interface_version; /* XEN_SYSCTL_INTERFACE_VERSION */
>      union {
>          struct xen_sysctl_readconsole       readconsole;
> @@ -700,6 +715,7 @@ struct xen_sysctl {
>          struct xen_sysctl_scheduler_op      scheduler_op;
>          struct xen_sysctl_coverage_op       coverage_op;
>          struct xen_sysctl_psr_cmt_op        psr_cmt_op;
> +        struct xen_sysctl_psr_cat_op        psr_cat_op;
>          uint8_t                             pad[128];
>      } u;
>  };