[PATCH v3 0/3] Expose PMU to the guests

[PATCH v3 0/3] Expose PMU to the guests

[Michal Orzel]

This patch series is a rework of an already pushed patch
exposing PMU to the guests. Since the second version the vpmu
parameter is common and prework in the form of reporting
availability of vPMU on the hardware is added.

The third version of the patch series removes the redundant check
from x86 code and modifies the way to define the flags XEN_DOMCTL_CDF and
XEN_SYSCTL_PHYSCAP, meaning not to define bit position and mask separately.

The current status is that the PMU registers are not virtualized
and the physical registers are directly accessible when "vpmu"
parameter is enabled in the guest config file. There is no interrupt
support and Xen will not save/restore the register values on context
switches. This is to be done in the future.

Michal Orzel (3):
  xen+tools: Introduce XEN_SYSCTL_PHYSCAP_vpmu
  xen/arm: Check for PMU platform support
  xen: Expose the PMU to the guests

 docs/man/xl.cfg.5.pod.in             | 17 ++++++++++
 tools/golang/xenlight/helpers.gen.go |  8 +++++
 tools/golang/xenlight/types.gen.go   |  2 ++
 tools/include/libxl.h                | 12 +++++++
 tools/libs/light/libxl.c             |  1 +
 tools/libs/light/libxl_create.c      |  4 +++
 tools/libs/light/libxl_types.idl     |  3 ++
 tools/ocaml/libs/xc/xenctrl.ml       |  2 ++
 tools/ocaml/libs/xc/xenctrl.mli      |  2 ++
 tools/xl/xl_info.c                   |  5 +--
 tools/xl/xl_parse.c                  |  2 ++
 xen/arch/arm/domain.c                | 10 ++++--
 xen/arch/arm/setup.c                 |  1 +
 xen/common/domain.c                  | 11 ++++++-
 xen/common/sysctl.c                  |  3 ++
 xen/include/asm-arm/cpufeature.h     | 49 ++++++++++++++++++++++++++--
 xen/include/asm-arm/domain.h         |  1 +
 xen/include/public/domctl.h          |  4 ++-
 xen/include/public/sysctl.h          |  6 ++--
 xen/include/xen/domain.h             |  2 ++
 20 files changed, 135 insertions(+), 10 deletions(-)

-- 
2.29.0

[PATCH v3 1/3] xen+tools: Introduce XEN_SYSCTL_PHYSCAP_vpmu

[Michal Orzel]

Introduce flag XEN_SYSCTL_PHYSCAP_vpmu which
indicates whether the platform supports vPMU
functionality. Modify Xen and tools accordingly.

Take the opportunity and fix XEN_SYSCTL_PHYSCAP_vmtrace
definition in sysctl.h which wrongly use (1<<6)
instead of (1u<<6).

Signed-off-by: Michal Orzel <michal.orzel@arm.com>
---
Changes since v2:
-do not define bit position and mask separately
Changes since v1:
-new in v2
---
 tools/golang/xenlight/helpers.gen.go | 2 ++
 tools/golang/xenlight/types.gen.go   | 1 +
 tools/include/libxl.h                | 6 ++++++
 tools/libs/light/libxl.c             | 1 +
 tools/libs/light/libxl_types.idl     | 1 +
 tools/ocaml/libs/xc/xenctrl.ml       | 1 +
 tools/ocaml/libs/xc/xenctrl.mli      | 1 +
 tools/xl/xl_info.c                   | 5 +++--
 xen/common/domain.c                  | 2 ++
 xen/common/sysctl.c                  | 3 +++
 xen/include/public/sysctl.h          | 6 ++++--
 xen/include/xen/domain.h             | 2 ++
 12 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/tools/golang/xenlight/helpers.gen.go b/tools/golang/xenlight/helpers.gen.go
index bfc1e7f312..c8669837d8 100644
--- a/tools/golang/xenlight/helpers.gen.go
+++ b/tools/golang/xenlight/helpers.gen.go
@@ -3360,6 +3360,7 @@ x.CapHap = bool(xc.cap_hap)
 x.CapShadow = bool(xc.cap_shadow)
 x.CapIommuHapPtShare = bool(xc.cap_iommu_hap_pt_share)
 x.CapVmtrace = bool(xc.cap_vmtrace)
+x.CapVpmu = bool(xc.cap_vpmu)
 
  return nil}
 
@@ -3391,6 +3392,7 @@ xc.cap_hap = C.bool(x.CapHap)
 xc.cap_shadow = C.bool(x.CapShadow)
 xc.cap_iommu_hap_pt_share = C.bool(x.CapIommuHapPtShare)
 xc.cap_vmtrace = C.bool(x.CapVmtrace)
+xc.cap_vpmu = C.bool(x.CapVpmu)
 
  return nil
  }
diff --git a/tools/golang/xenlight/types.gen.go b/tools/golang/xenlight/types.gen.go
index 09a3bb67e2..45f2cba3d2 100644
--- a/tools/golang/xenlight/types.gen.go
+++ b/tools/golang/xenlight/types.gen.go
@@ -1008,6 +1008,7 @@ CapHap bool
 CapShadow bool
 CapIommuHapPtShare bool
 CapVmtrace bool
+CapVpmu bool
 }
 
 type Connectorinfo struct {
diff --git a/tools/include/libxl.h b/tools/include/libxl.h
index b9ba16d698..ec5e3badae 100644
--- a/tools/include/libxl.h
+++ b/tools/include/libxl.h
@@ -502,6 +502,12 @@
  */
 #define LIBXL_HAVE_X86_MSR_RELAXED 1
 
+/*
+ * LIBXL_HAVE_PHYSINFO_CAP_VPMU indicates that libxl_physinfo has a cap_vpmu
+ * field, which indicates the availability of vPMU functionality.
+ */
+#define LIBXL_HAVE_PHYSINFO_CAP_VPMU 1
+
 /*
  * libxl ABI compatibility
  *
diff --git a/tools/libs/light/libxl.c b/tools/libs/light/libxl.c
index 204eb0be2d..a032723fde 100644
--- a/tools/libs/light/libxl.c
+++ b/tools/libs/light/libxl.c
@@ -404,6 +404,7 @@ int libxl_get_physinfo(libxl_ctx *ctx, libxl_physinfo *physinfo)
         !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share);
     physinfo->cap_vmtrace =
         !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_vmtrace);
+    physinfo->cap_vpmu = !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_vpmu);
 
     GC_FREE;
     return 0;
diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
index 3f9fff653a..993e83acca 100644
--- a/tools/libs/light/libxl_types.idl
+++ b/tools/libs/light/libxl_types.idl
@@ -1061,6 +1061,7 @@ libxl_physinfo = Struct("physinfo", [
     ("cap_shadow", bool),
     ("cap_iommu_hap_pt_share", bool),
     ("cap_vmtrace", bool),
+    ("cap_vpmu", bool),
     ], dir=DIR_OUT)
 
 libxl_connectorinfo = Struct("connectorinfo", [
diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
index a5588c643f..6da3ed3c6f 100644
--- a/tools/ocaml/libs/xc/xenctrl.ml
+++ b/tools/ocaml/libs/xc/xenctrl.ml
@@ -121,6 +121,7 @@ type physinfo_cap_flag =
 	| CAP_Shadow
 	| CAP_IOMMU_HAP_PT_SHARE
 	| CAP_Vmtrace
+	| CAP_Vpmu
 
 type physinfo =
 {
diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
index 6e94940a8a..b8faff6721 100644
--- a/tools/ocaml/libs/xc/xenctrl.mli
+++ b/tools/ocaml/libs/xc/xenctrl.mli
@@ -106,6 +106,7 @@ type physinfo_cap_flag =
   | CAP_Shadow
   | CAP_IOMMU_HAP_PT_SHARE
   | CAP_Vmtrace
+  | CAP_Vpmu
 
 type physinfo = {
   threads_per_core : int;
diff --git a/tools/xl/xl_info.c b/tools/xl/xl_info.c
index 8383e4a6df..2c86b317b7 100644
--- a/tools/xl/xl_info.c
+++ b/tools/xl/xl_info.c
@@ -210,7 +210,7 @@ static void output_physinfo(void)
          info.hw_cap[4], info.hw_cap[5], info.hw_cap[6], info.hw_cap[7]
         );
 
-    maybe_printf("virt_caps              :%s%s%s%s%s%s%s%s\n",
+    maybe_printf("virt_caps              :%s%s%s%s%s%s%s%s%s\n",
          info.cap_pv ? " pv" : "",
          info.cap_hvm ? " hvm" : "",
          info.cap_hvm && info.cap_hvm_directio ? " hvm_directio" : "",
@@ -218,7 +218,8 @@ static void output_physinfo(void)
          info.cap_hap ? " hap" : "",
          info.cap_shadow ? " shadow" : "",
          info.cap_iommu_hap_pt_share ? " iommu_hap_pt_share" : "",
-         info.cap_vmtrace ? " vmtrace" : ""
+         info.cap_vmtrace ? " vmtrace" : "",
+         info.cap_vpmu ? " vpmu" : ""
         );
 
     vinfo = libxl_get_version_info(ctx);
diff --git a/xen/common/domain.c b/xen/common/domain.c
index 6ee5d033b0..4d0e909eec 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -84,6 +84,8 @@ vcpu_info_t dummy_vcpu_info;
 
 bool __read_mostly vmtrace_available;
 
+bool __read_mostly vpmu_is_available;
+
 static void __domain_finalise_shutdown(struct domain *d)
 {
     struct vcpu *v;
diff --git a/xen/common/sysctl.c b/xen/common/sysctl.c
index 3558641cd9..6e7189bb3c 100644
--- a/xen/common/sysctl.c
+++ b/xen/common/sysctl.c
@@ -280,6 +280,9 @@ long do_sysctl(XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl)
         if ( vmtrace_available )
             pi->capabilities |= XEN_SYSCTL_PHYSCAP_vmtrace;
 
+        if ( vpmu_is_available )
+            pi->capabilities |= XEN_SYSCTL_PHYSCAP_vpmu;
+
         if ( copy_to_guest(u_sysctl, op, 1) )
             ret = -EFAULT;
     }
diff --git a/xen/include/public/sysctl.h b/xen/include/public/sysctl.h
index 039ccf885c..b794c9d351 100644
--- a/xen/include/public/sysctl.h
+++ b/xen/include/public/sysctl.h
@@ -100,10 +100,12 @@ struct xen_sysctl_tbuf_op {
 #define _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share 5
 #define XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share  \
     (1u << _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share)
-#define XEN_SYSCTL_PHYSCAP_vmtrace       (1 << 6)
+#define XEN_SYSCTL_PHYSCAP_vmtrace       (1u<<6)
+/* The platform supports vPMU. */
+#define XEN_SYSCTL_PHYSCAP_vpmu          (1u<<7)
 
 /* Max XEN_SYSCTL_PHYSCAP_* constant.  Used for ABI checking. */
-#define XEN_SYSCTL_PHYSCAP_MAX XEN_SYSCTL_PHYSCAP_vmtrace
+#define XEN_SYSCTL_PHYSCAP_MAX XEN_SYSCTL_PHYSCAP_vpmu
 
 struct xen_sysctl_physinfo {
     uint32_t threads_per_core;
diff --git a/xen/include/xen/domain.h b/xen/include/xen/domain.h
index 1708c36964..160c8dbdab 100644
--- a/xen/include/xen/domain.h
+++ b/xen/include/xen/domain.h
@@ -133,4 +133,6 @@ static inline void vnuma_destroy(struct vnuma_info *vnuma) { ASSERT(!vnuma); }
 
 extern bool vmtrace_available;
 
+extern bool vpmu_is_available;
+
 #endif /* __XEN_DOMAIN_H__ */
-- 
2.29.0

Re: [PATCH v3 1/3] xen+tools: Introduce XEN_SYSCTL_PHYSCAP_vpmu

[Bertrand Marquis]

Hi Michal

> On 8 Oct 2021, at 09:19, Michal Orzel <Michal.Orzel@arm.com> wrote:
> 
> Introduce flag XEN_SYSCTL_PHYSCAP_vpmu which
> indicates whether the platform supports vPMU
> functionality. Modify Xen and tools accordingly.
> 
> Take the opportunity and fix XEN_SYSCTL_PHYSCAP_vmtrace
> definition in sysctl.h which wrongly use (1<<6)
> instead of (1u<<6).
> 
> Signed-off-by: Michal Orzel <michal.orzel@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>

Cheers
Bertrand

> ---
> Changes since v2:
> -do not define bit position and mask separately
> Changes since v1:
> -new in v2
> ---
> tools/golang/xenlight/helpers.gen.go | 2 ++
> tools/golang/xenlight/types.gen.go   | 1 +
> tools/include/libxl.h                | 6 ++++++
> tools/libs/light/libxl.c             | 1 +
> tools/libs/light/libxl_types.idl     | 1 +
> tools/ocaml/libs/xc/xenctrl.ml       | 1 +
> tools/ocaml/libs/xc/xenctrl.mli      | 1 +
> tools/xl/xl_info.c                   | 5 +++--
> xen/common/domain.c                  | 2 ++
> xen/common/sysctl.c                  | 3 +++
> xen/include/public/sysctl.h          | 6 ++++--
> xen/include/xen/domain.h             | 2 ++
> 12 files changed, 27 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/golang/xenlight/helpers.gen.go b/tools/golang/xenlight/helpers.gen.go
> index bfc1e7f312..c8669837d8 100644
> --- a/tools/golang/xenlight/helpers.gen.go
> +++ b/tools/golang/xenlight/helpers.gen.go
> @@ -3360,6 +3360,7 @@ x.CapHap = bool(xc.cap_hap)
> x.CapShadow = bool(xc.cap_shadow)
> x.CapIommuHapPtShare = bool(xc.cap_iommu_hap_pt_share)
> x.CapVmtrace = bool(xc.cap_vmtrace)
> +x.CapVpmu = bool(xc.cap_vpmu)
> 
>  return nil}
> 
> @@ -3391,6 +3392,7 @@ xc.cap_hap = C.bool(x.CapHap)
> xc.cap_shadow = C.bool(x.CapShadow)
> xc.cap_iommu_hap_pt_share = C.bool(x.CapIommuHapPtShare)
> xc.cap_vmtrace = C.bool(x.CapVmtrace)
> +xc.cap_vpmu = C.bool(x.CapVpmu)
> 
>  return nil
>  }
> diff --git a/tools/golang/xenlight/types.gen.go b/tools/golang/xenlight/types.gen.go
> index 09a3bb67e2..45f2cba3d2 100644
> --- a/tools/golang/xenlight/types.gen.go
> +++ b/tools/golang/xenlight/types.gen.go
> @@ -1008,6 +1008,7 @@ CapHap bool
> CapShadow bool
> CapIommuHapPtShare bool
> CapVmtrace bool
> +CapVpmu bool
> }
> 
> type Connectorinfo struct {
> diff --git a/tools/include/libxl.h b/tools/include/libxl.h
> index b9ba16d698..ec5e3badae 100644
> --- a/tools/include/libxl.h
> +++ b/tools/include/libxl.h
> @@ -502,6 +502,12 @@
>  */
> #define LIBXL_HAVE_X86_MSR_RELAXED 1
> 
> +/*
> + * LIBXL_HAVE_PHYSINFO_CAP_VPMU indicates that libxl_physinfo has a cap_vpmu
> + * field, which indicates the availability of vPMU functionality.
> + */
> +#define LIBXL_HAVE_PHYSINFO_CAP_VPMU 1
> +
> /*
>  * libxl ABI compatibility
>  *
> diff --git a/tools/libs/light/libxl.c b/tools/libs/light/libxl.c
> index 204eb0be2d..a032723fde 100644
> --- a/tools/libs/light/libxl.c
> +++ b/tools/libs/light/libxl.c
> @@ -404,6 +404,7 @@ int libxl_get_physinfo(libxl_ctx *ctx, libxl_physinfo *physinfo)
>         !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share);
>     physinfo->cap_vmtrace =
>         !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_vmtrace);
> +    physinfo->cap_vpmu = !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_vpmu);
> 
>     GC_FREE;
>     return 0;
> diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
> index 3f9fff653a..993e83acca 100644
> --- a/tools/libs/light/libxl_types.idl
> +++ b/tools/libs/light/libxl_types.idl
> @@ -1061,6 +1061,7 @@ libxl_physinfo = Struct("physinfo", [
>     ("cap_shadow", bool),
>     ("cap_iommu_hap_pt_share", bool),
>     ("cap_vmtrace", bool),
> +    ("cap_vpmu", bool),
>     ], dir=DIR_OUT)
> 
> libxl_connectorinfo = Struct("connectorinfo", [
> diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
> index a5588c643f..6da3ed3c6f 100644
> --- a/tools/ocaml/libs/xc/xenctrl.ml
> +++ b/tools/ocaml/libs/xc/xenctrl.ml
> @@ -121,6 +121,7 @@ type physinfo_cap_flag =
> 	| CAP_Shadow
> 	| CAP_IOMMU_HAP_PT_SHARE
> 	| CAP_Vmtrace
> +	| CAP_Vpmu
> 
> type physinfo =
> {
> diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
> index 6e94940a8a..b8faff6721 100644
> --- a/tools/ocaml/libs/xc/xenctrl.mli
> +++ b/tools/ocaml/libs/xc/xenctrl.mli
> @@ -106,6 +106,7 @@ type physinfo_cap_flag =
>   | CAP_Shadow
>   | CAP_IOMMU_HAP_PT_SHARE
>   | CAP_Vmtrace
> +  | CAP_Vpmu
> 
> type physinfo = {
>   threads_per_core : int;
> diff --git a/tools/xl/xl_info.c b/tools/xl/xl_info.c
> index 8383e4a6df..2c86b317b7 100644
> --- a/tools/xl/xl_info.c
> +++ b/tools/xl/xl_info.c
> @@ -210,7 +210,7 @@ static void output_physinfo(void)
>          info.hw_cap[4], info.hw_cap[5], info.hw_cap[6], info.hw_cap[7]
>         );
> 
> -    maybe_printf("virt_caps              :%s%s%s%s%s%s%s%s\n",
> +    maybe_printf("virt_caps              :%s%s%s%s%s%s%s%s%s\n",
>          info.cap_pv ? " pv" : "",
>          info.cap_hvm ? " hvm" : "",
>          info.cap_hvm && info.cap_hvm_directio ? " hvm_directio" : "",
> @@ -218,7 +218,8 @@ static void output_physinfo(void)
>          info.cap_hap ? " hap" : "",
>          info.cap_shadow ? " shadow" : "",
>          info.cap_iommu_hap_pt_share ? " iommu_hap_pt_share" : "",
> -         info.cap_vmtrace ? " vmtrace" : ""
> +         info.cap_vmtrace ? " vmtrace" : "",
> +         info.cap_vpmu ? " vpmu" : ""
>         );
> 
>     vinfo = libxl_get_version_info(ctx);
> diff --git a/xen/common/domain.c b/xen/common/domain.c
> index 6ee5d033b0..4d0e909eec 100644
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -84,6 +84,8 @@ vcpu_info_t dummy_vcpu_info;
> 
> bool __read_mostly vmtrace_available;
> 
> +bool __read_mostly vpmu_is_available;
> +
> static void __domain_finalise_shutdown(struct domain *d)
> {
>     struct vcpu *v;
> diff --git a/xen/common/sysctl.c b/xen/common/sysctl.c
> index 3558641cd9..6e7189bb3c 100644
> --- a/xen/common/sysctl.c
> +++ b/xen/common/sysctl.c
> @@ -280,6 +280,9 @@ long do_sysctl(XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl)
>         if ( vmtrace_available )
>             pi->capabilities |= XEN_SYSCTL_PHYSCAP_vmtrace;
> 
> +        if ( vpmu_is_available )
> +            pi->capabilities |= XEN_SYSCTL_PHYSCAP_vpmu;
> +
>         if ( copy_to_guest(u_sysctl, op, 1) )
>             ret = -EFAULT;
>     }
> diff --git a/xen/include/public/sysctl.h b/xen/include/public/sysctl.h
> index 039ccf885c..b794c9d351 100644
> --- a/xen/include/public/sysctl.h
> +++ b/xen/include/public/sysctl.h
> @@ -100,10 +100,12 @@ struct xen_sysctl_tbuf_op {
> #define _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share 5
> #define XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share  \
>     (1u << _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share)
> -#define XEN_SYSCTL_PHYSCAP_vmtrace       (1 << 6)
> +#define XEN_SYSCTL_PHYSCAP_vmtrace       (1u<<6)
> +/* The platform supports vPMU. */
> +#define XEN_SYSCTL_PHYSCAP_vpmu          (1u<<7)
> 
> /* Max XEN_SYSCTL_PHYSCAP_* constant.  Used for ABI checking. */
> -#define XEN_SYSCTL_PHYSCAP_MAX XEN_SYSCTL_PHYSCAP_vmtrace
> +#define XEN_SYSCTL_PHYSCAP_MAX XEN_SYSCTL_PHYSCAP_vpmu
> 
> struct xen_sysctl_physinfo {
>     uint32_t threads_per_core;
> diff --git a/xen/include/xen/domain.h b/xen/include/xen/domain.h
> index 1708c36964..160c8dbdab 100644
> --- a/xen/include/xen/domain.h
> +++ b/xen/include/xen/domain.h
> @@ -133,4 +133,6 @@ static inline void vnuma_destroy(struct vnuma_info *vnuma) { ASSERT(!vnuma); }
> 
> extern bool vmtrace_available;
> 
> +extern bool vpmu_is_available;
> +
> #endif /* __XEN_DOMAIN_H__ */
> -- 
> 2.29.0
> 
> 

Re: [PATCH v3 1/3] xen+tools: Introduce XEN_SYSCTL_PHYSCAP_vpmu

[Jan Beulich]

On 08.10.2021 10:19, Michal Orzel wrote:
> --- a/xen/include/public/sysctl.h
> +++ b/xen/include/public/sysctl.h
> @@ -100,10 +100,12 @@ struct xen_sysctl_tbuf_op {
>  #define _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share 5
>  #define XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share  \
>      (1u << _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share)
> -#define XEN_SYSCTL_PHYSCAP_vmtrace       (1 << 6)
> +#define XEN_SYSCTL_PHYSCAP_vmtrace       (1u<<6)
> +/* The platform supports vPMU. */
> +#define XEN_SYSCTL_PHYSCAP_vpmu          (1u<<7)

While purely cosmetic and easily fixable while committing, I still
fail to understand why you did drop the blanks from the expression
you adjust and why you didn't add blanks to the new expression.
./CODING_STYLE is quite clear in this respect, and even the code
in context does not suggest any alternative style. (While code just
outside of visible context does, it should not be used as excuse
to introduce further style violations.)

Jan

Re: [PATCH v3 1/3] xen+tools: Introduce XEN_SYSCTL_PHYSCAP_vpmu

[Michal Orzel]

Hi Jan,

On 08.10.2021 10:33, Jan Beulich wrote:
> On 08.10.2021 10:19, Michal Orzel wrote:
>> --- a/xen/include/public/sysctl.h
>> +++ b/xen/include/public/sysctl.h
>> @@ -100,10 +100,12 @@ struct xen_sysctl_tbuf_op {
>>  #define _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share 5
>>  #define XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share  \
>>      (1u << _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share)
>> -#define XEN_SYSCTL_PHYSCAP_vmtrace       (1 << 6)
>> +#define XEN_SYSCTL_PHYSCAP_vmtrace       (1u<<6)
>> +/* The platform supports vPMU. */
>> +#define XEN_SYSCTL_PHYSCAP_vpmu          (1u<<7)
> 
> While purely cosmetic and easily fixable while committing, I still
> fail to understand why you did drop the blanks from the expression
> you adjust and why you didn't add blanks to the new expression.
> ./CODING_STYLE is quite clear in this respect, and even the code
> in context does not suggest any alternative style. (While code just
> outside of visible context does, it should not be used as excuse
> to introduce further style violations.)
> 
I was just biased by the previous entries.
Previous entries were not added at once but commit after commit.
No one did any remarks on that so I decided to stick to the "section standard".
From now one I will be looking only at the coding style even though the section
is doing something else. If it is possible, please fix it while commiting.

> Jan
> 

Cheers,
Michal

Re: [PATCH v3 1/3] xen+tools: Introduce XEN_SYSCTL_PHYSCAP_vpmu

[Nick Rosbrook]

On Fri, Oct 08, 2021 at 10:19:31AM +0200, Michal Orzel wrote:
> Introduce flag XEN_SYSCTL_PHYSCAP_vpmu which
> indicates whether the platform supports vPMU
> functionality. Modify Xen and tools accordingly.
> 
> Take the opportunity and fix XEN_SYSCTL_PHYSCAP_vmtrace
> definition in sysctl.h which wrongly use (1<<6)
> instead of (1u<<6).
> 
> Signed-off-by: Michal Orzel <michal.orzel@arm.com>
> ---
> Changes since v2:
> -do not define bit position and mask separately
> Changes since v1:
> -new in v2
> ---
>  tools/golang/xenlight/helpers.gen.go | 2 ++
>  tools/golang/xenlight/types.gen.go   | 1 +
>  tools/include/libxl.h                | 6 ++++++
>  tools/libs/light/libxl.c             | 1 +
>  tools/libs/light/libxl_types.idl     | 1 +
>  tools/ocaml/libs/xc/xenctrl.ml       | 1 +
>  tools/ocaml/libs/xc/xenctrl.mli      | 1 +
>  tools/xl/xl_info.c                   | 5 +++--
>  xen/common/domain.c                  | 2 ++
>  xen/common/sysctl.c                  | 3 +++
>  xen/include/public/sysctl.h          | 6 ++++--
>  xen/include/xen/domain.h             | 2 ++
>  12 files changed, 27 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/golang/xenlight/helpers.gen.go b/tools/golang/xenlight/helpers.gen.go
> index bfc1e7f312..c8669837d8 100644
> --- a/tools/golang/xenlight/helpers.gen.go
> +++ b/tools/golang/xenlight/helpers.gen.go
> @@ -3360,6 +3360,7 @@ x.CapHap = bool(xc.cap_hap)
>  x.CapShadow = bool(xc.cap_shadow)
>  x.CapIommuHapPtShare = bool(xc.cap_iommu_hap_pt_share)
>  x.CapVmtrace = bool(xc.cap_vmtrace)
> +x.CapVpmu = bool(xc.cap_vpmu)
>  
>   return nil}
>  
> @@ -3391,6 +3392,7 @@ xc.cap_hap = C.bool(x.CapHap)
>  xc.cap_shadow = C.bool(x.CapShadow)
>  xc.cap_iommu_hap_pt_share = C.bool(x.CapIommuHapPtShare)
>  xc.cap_vmtrace = C.bool(x.CapVmtrace)
> +xc.cap_vpmu = C.bool(x.CapVpmu)
>  
>   return nil
>   }
> diff --git a/tools/golang/xenlight/types.gen.go b/tools/golang/xenlight/types.gen.go
> index 09a3bb67e2..45f2cba3d2 100644
> --- a/tools/golang/xenlight/types.gen.go
> +++ b/tools/golang/xenlight/types.gen.go
> @@ -1008,6 +1008,7 @@ CapHap bool
>  CapShadow bool
>  CapIommuHapPtShare bool
>  CapVmtrace bool
> +CapVpmu bool
>  }

For the golang re-gen,

Acked-by: Nick Rosbrook <rosbrookn@ainfosec.com>

Thanks,
NR

Re: [PATCH v3 1/3] xen+tools: Introduce XEN_SYSCTL_PHYSCAP_vpmu

[Stefano Stabellini]

On Fri, 8 Oct 2021, Michal Orzel wrote:
> Introduce flag XEN_SYSCTL_PHYSCAP_vpmu which
> indicates whether the platform supports vPMU
> functionality. Modify Xen and tools accordingly.
> 
> Take the opportunity and fix XEN_SYSCTL_PHYSCAP_vmtrace
> definition in sysctl.h which wrongly use (1<<6)
> instead of (1u<<6).
> 
> Signed-off-by: Michal Orzel <michal.orzel@arm.com>

Aside from the minor style issue Jan pointed out:

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
> Changes since v2:
> -do not define bit position and mask separately
> Changes since v1:
> -new in v2
> ---
>  tools/golang/xenlight/helpers.gen.go | 2 ++
>  tools/golang/xenlight/types.gen.go   | 1 +
>  tools/include/libxl.h                | 6 ++++++
>  tools/libs/light/libxl.c             | 1 +
>  tools/libs/light/libxl_types.idl     | 1 +
>  tools/ocaml/libs/xc/xenctrl.ml       | 1 +
>  tools/ocaml/libs/xc/xenctrl.mli      | 1 +
>  tools/xl/xl_info.c                   | 5 +++--
>  xen/common/domain.c                  | 2 ++
>  xen/common/sysctl.c                  | 3 +++
>  xen/include/public/sysctl.h          | 6 ++++--
>  xen/include/xen/domain.h             | 2 ++
>  12 files changed, 27 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/golang/xenlight/helpers.gen.go b/tools/golang/xenlight/helpers.gen.go
> index bfc1e7f312..c8669837d8 100644
> --- a/tools/golang/xenlight/helpers.gen.go
> +++ b/tools/golang/xenlight/helpers.gen.go
> @@ -3360,6 +3360,7 @@ x.CapHap = bool(xc.cap_hap)
>  x.CapShadow = bool(xc.cap_shadow)
>  x.CapIommuHapPtShare = bool(xc.cap_iommu_hap_pt_share)
>  x.CapVmtrace = bool(xc.cap_vmtrace)
> +x.CapVpmu = bool(xc.cap_vpmu)
>  
>   return nil}
>  
> @@ -3391,6 +3392,7 @@ xc.cap_hap = C.bool(x.CapHap)
>  xc.cap_shadow = C.bool(x.CapShadow)
>  xc.cap_iommu_hap_pt_share = C.bool(x.CapIommuHapPtShare)
>  xc.cap_vmtrace = C.bool(x.CapVmtrace)
> +xc.cap_vpmu = C.bool(x.CapVpmu)
>  
>   return nil
>   }
> diff --git a/tools/golang/xenlight/types.gen.go b/tools/golang/xenlight/types.gen.go
> index 09a3bb67e2..45f2cba3d2 100644
> --- a/tools/golang/xenlight/types.gen.go
> +++ b/tools/golang/xenlight/types.gen.go
> @@ -1008,6 +1008,7 @@ CapHap bool
>  CapShadow bool
>  CapIommuHapPtShare bool
>  CapVmtrace bool
> +CapVpmu bool
>  }
>  
>  type Connectorinfo struct {
> diff --git a/tools/include/libxl.h b/tools/include/libxl.h
> index b9ba16d698..ec5e3badae 100644
> --- a/tools/include/libxl.h
> +++ b/tools/include/libxl.h
> @@ -502,6 +502,12 @@
>   */
>  #define LIBXL_HAVE_X86_MSR_RELAXED 1
>  
> +/*
> + * LIBXL_HAVE_PHYSINFO_CAP_VPMU indicates that libxl_physinfo has a cap_vpmu
> + * field, which indicates the availability of vPMU functionality.
> + */
> +#define LIBXL_HAVE_PHYSINFO_CAP_VPMU 1
> +
>  /*
>   * libxl ABI compatibility
>   *
> diff --git a/tools/libs/light/libxl.c b/tools/libs/light/libxl.c
> index 204eb0be2d..a032723fde 100644
> --- a/tools/libs/light/libxl.c
> +++ b/tools/libs/light/libxl.c
> @@ -404,6 +404,7 @@ int libxl_get_physinfo(libxl_ctx *ctx, libxl_physinfo *physinfo)
>          !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share);
>      physinfo->cap_vmtrace =
>          !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_vmtrace);
> +    physinfo->cap_vpmu = !!(xcphysinfo.capabilities & XEN_SYSCTL_PHYSCAP_vpmu);
>  
>      GC_FREE;
>      return 0;
> diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
> index 3f9fff653a..993e83acca 100644
> --- a/tools/libs/light/libxl_types.idl
> +++ b/tools/libs/light/libxl_types.idl
> @@ -1061,6 +1061,7 @@ libxl_physinfo = Struct("physinfo", [
>      ("cap_shadow", bool),
>      ("cap_iommu_hap_pt_share", bool),
>      ("cap_vmtrace", bool),
> +    ("cap_vpmu", bool),
>      ], dir=DIR_OUT)
>  
>  libxl_connectorinfo = Struct("connectorinfo", [
> diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
> index a5588c643f..6da3ed3c6f 100644
> --- a/tools/ocaml/libs/xc/xenctrl.ml
> +++ b/tools/ocaml/libs/xc/xenctrl.ml
> @@ -121,6 +121,7 @@ type physinfo_cap_flag =
>  	| CAP_Shadow
>  	| CAP_IOMMU_HAP_PT_SHARE
>  	| CAP_Vmtrace
> +	| CAP_Vpmu
>  
>  type physinfo =
>  {
> diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
> index 6e94940a8a..b8faff6721 100644
> --- a/tools/ocaml/libs/xc/xenctrl.mli
> +++ b/tools/ocaml/libs/xc/xenctrl.mli
> @@ -106,6 +106,7 @@ type physinfo_cap_flag =
>    | CAP_Shadow
>    | CAP_IOMMU_HAP_PT_SHARE
>    | CAP_Vmtrace
> +  | CAP_Vpmu
>  
>  type physinfo = {
>    threads_per_core : int;
> diff --git a/tools/xl/xl_info.c b/tools/xl/xl_info.c
> index 8383e4a6df..2c86b317b7 100644
> --- a/tools/xl/xl_info.c
> +++ b/tools/xl/xl_info.c
> @@ -210,7 +210,7 @@ static void output_physinfo(void)
>           info.hw_cap[4], info.hw_cap[5], info.hw_cap[6], info.hw_cap[7]
>          );
>  
> -    maybe_printf("virt_caps              :%s%s%s%s%s%s%s%s\n",
> +    maybe_printf("virt_caps              :%s%s%s%s%s%s%s%s%s\n",
>           info.cap_pv ? " pv" : "",
>           info.cap_hvm ? " hvm" : "",
>           info.cap_hvm && info.cap_hvm_directio ? " hvm_directio" : "",
> @@ -218,7 +218,8 @@ static void output_physinfo(void)
>           info.cap_hap ? " hap" : "",
>           info.cap_shadow ? " shadow" : "",
>           info.cap_iommu_hap_pt_share ? " iommu_hap_pt_share" : "",
> -         info.cap_vmtrace ? " vmtrace" : ""
> +         info.cap_vmtrace ? " vmtrace" : "",
> +         info.cap_vpmu ? " vpmu" : ""
>          );
>  
>      vinfo = libxl_get_version_info(ctx);
> diff --git a/xen/common/domain.c b/xen/common/domain.c
> index 6ee5d033b0..4d0e909eec 100644
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -84,6 +84,8 @@ vcpu_info_t dummy_vcpu_info;
>  
>  bool __read_mostly vmtrace_available;
>  
> +bool __read_mostly vpmu_is_available;
> +
>  static void __domain_finalise_shutdown(struct domain *d)
>  {
>      struct vcpu *v;
> diff --git a/xen/common/sysctl.c b/xen/common/sysctl.c
> index 3558641cd9..6e7189bb3c 100644
> --- a/xen/common/sysctl.c
> +++ b/xen/common/sysctl.c
> @@ -280,6 +280,9 @@ long do_sysctl(XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl)
>          if ( vmtrace_available )
>              pi->capabilities |= XEN_SYSCTL_PHYSCAP_vmtrace;
>  
> +        if ( vpmu_is_available )
> +            pi->capabilities |= XEN_SYSCTL_PHYSCAP_vpmu;
> +
>          if ( copy_to_guest(u_sysctl, op, 1) )
>              ret = -EFAULT;
>      }
> diff --git a/xen/include/public/sysctl.h b/xen/include/public/sysctl.h
> index 039ccf885c..b794c9d351 100644
> --- a/xen/include/public/sysctl.h
> +++ b/xen/include/public/sysctl.h
> @@ -100,10 +100,12 @@ struct xen_sysctl_tbuf_op {
>  #define _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share 5
>  #define XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share  \
>      (1u << _XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share)
> -#define XEN_SYSCTL_PHYSCAP_vmtrace       (1 << 6)
> +#define XEN_SYSCTL_PHYSCAP_vmtrace       (1u<<6)
> +/* The platform supports vPMU. */
> +#define XEN_SYSCTL_PHYSCAP_vpmu          (1u<<7)
>  
>  /* Max XEN_SYSCTL_PHYSCAP_* constant.  Used for ABI checking. */
> -#define XEN_SYSCTL_PHYSCAP_MAX XEN_SYSCTL_PHYSCAP_vmtrace
> +#define XEN_SYSCTL_PHYSCAP_MAX XEN_SYSCTL_PHYSCAP_vpmu
>  
>  struct xen_sysctl_physinfo {
>      uint32_t threads_per_core;
> diff --git a/xen/include/xen/domain.h b/xen/include/xen/domain.h
> index 1708c36964..160c8dbdab 100644
> --- a/xen/include/xen/domain.h
> +++ b/xen/include/xen/domain.h
> @@ -133,4 +133,6 @@ static inline void vnuma_destroy(struct vnuma_info *vnuma) { ASSERT(!vnuma); }
>  
>  extern bool vmtrace_available;
>  
> +extern bool vpmu_is_available;
> +
>  #endif /* __XEN_DOMAIN_H__ */
> -- 
> 2.29.0
> 

[PATCH v3 2/3] xen/arm: Check for PMU platform support

[Michal Orzel]

ID_AA64DFR0_EL1/ID_DFR0_EL1 registers provide
information about PMU support. Replace structure
dbg64/dbg32 with a union and fill in all the
register fields according to document:
ARM Architecture Registers(DDI 0595, 2021-06).

Add macros boot_dbg_feature64/boot_dbg_feature32
to check for a debug feature. Add macro
cpu_has_pmu to check for PMU support.

Signed-off-by: Michal Orzel <michal.orzel@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---
Changes since v2:
-none
Changes since v1:
-new in v2
---
 xen/include/asm-arm/cpufeature.h | 49 ++++++++++++++++++++++++++++++--
 1 file changed, 47 insertions(+), 2 deletions(-)

diff --git a/xen/include/asm-arm/cpufeature.h b/xen/include/asm-arm/cpufeature.h
index 5ca09b0bff..4fce23844d 100644
--- a/xen/include/asm-arm/cpufeature.h
+++ b/xen/include/asm-arm/cpufeature.h
@@ -4,6 +4,7 @@
 #ifdef CONFIG_ARM_64
 #define cpu_feature64(c, feat)         ((c)->pfr64.feat)
 #define boot_cpu_feature64(feat)       (system_cpuinfo.pfr64.feat)
+#define boot_dbg_feature64(feat)       (system_cpuinfo.dbg64.feat)
 
 #define cpu_feature64_has_el0_32(c)    (cpu_feature64(c, el0) == 2)
 
@@ -22,6 +23,7 @@
 
 #define cpu_feature32(c, feat)         ((c)->pfr32.feat)
 #define boot_cpu_feature32(feat)       (system_cpuinfo.pfr32.feat)
+#define boot_dbg_feature32(feat)       (system_cpuinfo.dbg32.feat)
 
 #define cpu_has_arm       (boot_cpu_feature32(arm) == 1)
 #define cpu_has_thumb     (boot_cpu_feature32(thumb) >= 1)
@@ -32,8 +34,10 @@
 
 #ifdef CONFIG_ARM_32
 #define cpu_has_gentimer  (boot_cpu_feature32(gentimer) == 1)
+#define cpu_has_pmu       (boot_dbg_feature32(perfmon) >= 1)
 #else
 #define cpu_has_gentimer  (1)
+#define cpu_has_pmu       (boot_dbg_feature64(pmu_ver) >= 1)
 #endif
 #define cpu_has_security  (boot_cpu_feature32(security) > 0)
 
@@ -181,8 +185,28 @@ struct cpuinfo_arm {
         };
     } pfr64;
 
-    struct {
+    union {
         register_t bits[2];
+        struct {
+            /* DFR0 */
+            unsigned long debug_ver:4;
+            unsigned long trace_ver:4;
+            unsigned long pmu_ver:4;
+            unsigned long brps:4;
+            unsigned long __res0:4;
+            unsigned long wrps:4;
+            unsigned long __res1:4;
+            unsigned long ctx_cmps:4;
+            unsigned long pms_ver:4;
+            unsigned long double_lock:4;
+            unsigned long trace_filt:4;
+            unsigned long __res2:4;
+            unsigned long mtpmu:4;
+            unsigned long __res3:12;
+
+            /* DFR1 */
+            unsigned long __res4:64;
+        };
     } dbg64;
 
     struct {
@@ -321,8 +345,29 @@ struct cpuinfo_arm {
         };
     } pfr32;
 
-    struct {
+    union {
         register_t bits[2];
+        struct {
+            /* DFR0 */
+            unsigned long copdbg:4;
+            unsigned long copsdbg:4;
+            unsigned long mmapdbg:4;
+            unsigned long coptrc:4;
+            unsigned long mmaptrc:4;
+            unsigned long mprofdbg:4;
+            unsigned long perfmon:4;
+            unsigned long tracefilt:4;
+#ifdef CONFIG_ARM_64
+            unsigned long __res0:32;
+#endif
+
+            /* DFR1 */
+            unsigned long mtpmu:4;
+            unsigned long __res1:28;
+#ifdef CONFIG_ARM_64
+            unsigned long __res2:32;
+#endif
+        };
     } dbg32;
 
     struct {
-- 
2.29.0

Re: [PATCH v3 2/3] xen/arm: Check for PMU platform support

[Bertrand Marquis]

Hi Michal,

> On 8 Oct 2021, at 09:19, Michal Orzel <Michal.Orzel@arm.com> wrote:
> 
> ID_AA64DFR0_EL1/ID_DFR0_EL1 registers provide
> information about PMU support. Replace structure
> dbg64/dbg32 with a union and fill in all the
> register fields according to document:
> ARM Architecture Registers(DDI 0595, 2021-06).
> 
> Add macros boot_dbg_feature64/boot_dbg_feature32
> to check for a debug feature. Add macro
> cpu_has_pmu to check for PMU support.
> 
> Signed-off-by: Michal Orzel <michal.orzel@arm.com>
> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>

Cheers
Bertrand

> ---
> Changes since v2:
> -none
> Changes since v1:
> -new in v2
> ---
> xen/include/asm-arm/cpufeature.h | 49 ++++++++++++++++++++++++++++++--
> 1 file changed, 47 insertions(+), 2 deletions(-)
> 
> diff --git a/xen/include/asm-arm/cpufeature.h b/xen/include/asm-arm/cpufeature.h
> index 5ca09b0bff..4fce23844d 100644
> --- a/xen/include/asm-arm/cpufeature.h
> +++ b/xen/include/asm-arm/cpufeature.h
> @@ -4,6 +4,7 @@
> #ifdef CONFIG_ARM_64
> #define cpu_feature64(c, feat)         ((c)->pfr64.feat)
> #define boot_cpu_feature64(feat)       (system_cpuinfo.pfr64.feat)
> +#define boot_dbg_feature64(feat)       (system_cpuinfo.dbg64.feat)
> 
> #define cpu_feature64_has_el0_32(c)    (cpu_feature64(c, el0) == 2)
> 
> @@ -22,6 +23,7 @@
> 
> #define cpu_feature32(c, feat)         ((c)->pfr32.feat)
> #define boot_cpu_feature32(feat)       (system_cpuinfo.pfr32.feat)
> +#define boot_dbg_feature32(feat)       (system_cpuinfo.dbg32.feat)
> 
> #define cpu_has_arm       (boot_cpu_feature32(arm) == 1)
> #define cpu_has_thumb     (boot_cpu_feature32(thumb) >= 1)
> @@ -32,8 +34,10 @@
> 
> #ifdef CONFIG_ARM_32
> #define cpu_has_gentimer  (boot_cpu_feature32(gentimer) == 1)
> +#define cpu_has_pmu       (boot_dbg_feature32(perfmon) >= 1)
> #else
> #define cpu_has_gentimer  (1)
> +#define cpu_has_pmu       (boot_dbg_feature64(pmu_ver) >= 1)
> #endif
> #define cpu_has_security  (boot_cpu_feature32(security) > 0)
> 
> @@ -181,8 +185,28 @@ struct cpuinfo_arm {
>         };
>     } pfr64;
> 
> -    struct {
> +    union {
>         register_t bits[2];
> +        struct {
> +            /* DFR0 */
> +            unsigned long debug_ver:4;
> +            unsigned long trace_ver:4;
> +            unsigned long pmu_ver:4;
> +            unsigned long brps:4;
> +            unsigned long __res0:4;
> +            unsigned long wrps:4;
> +            unsigned long __res1:4;
> +            unsigned long ctx_cmps:4;
> +            unsigned long pms_ver:4;
> +            unsigned long double_lock:4;
> +            unsigned long trace_filt:4;
> +            unsigned long __res2:4;
> +            unsigned long mtpmu:4;
> +            unsigned long __res3:12;
> +
> +            /* DFR1 */
> +            unsigned long __res4:64;
> +        };
>     } dbg64;
> 
>     struct {
> @@ -321,8 +345,29 @@ struct cpuinfo_arm {
>         };
>     } pfr32;
> 
> -    struct {
> +    union {
>         register_t bits[2];
> +        struct {
> +            /* DFR0 */
> +            unsigned long copdbg:4;
> +            unsigned long copsdbg:4;
> +            unsigned long mmapdbg:4;
> +            unsigned long coptrc:4;
> +            unsigned long mmaptrc:4;
> +            unsigned long mprofdbg:4;
> +            unsigned long perfmon:4;
> +            unsigned long tracefilt:4;
> +#ifdef CONFIG_ARM_64
> +            unsigned long __res0:32;
> +#endif
> +
> +            /* DFR1 */
> +            unsigned long mtpmu:4;
> +            unsigned long __res1:28;
> +#ifdef CONFIG_ARM_64
> +            unsigned long __res2:32;
> +#endif
> +        };
>     } dbg32;
> 
>     struct {
> -- 
> 2.29.0
> 
> 

[PATCH v3 3/3] xen: Expose the PMU to the guests

[Michal Orzel]

Add parameter vpmu to xl domain configuration syntax
to enable the access to PMU registers by disabling
the PMU traps(currently only for ARM).

The current status is that the PMU registers are not
virtualized and the physical registers are directly
accessible when this parameter is enabled. There is no
interrupt support and Xen will not save/restore the
register values on context switches.

Please note that this feature is experimental.

Signed-off-by: Michal Orzel <michal.orzel@arm.com>
Signed-off-by: Julien Grall <julien@xen.org>
---
Changes since v2:
-remove redundant check from x86 code
-do not define bit position and mask separately
Changes since v1:
-modify vpmu parameter to be common rather than arch specific
---
 docs/man/xl.cfg.5.pod.in             | 17 +++++++++++++++++
 tools/golang/xenlight/helpers.gen.go |  6 ++++++
 tools/golang/xenlight/types.gen.go   |  1 +
 tools/include/libxl.h                |  6 ++++++
 tools/libs/light/libxl_create.c      |  4 ++++
 tools/libs/light/libxl_types.idl     |  2 ++
 tools/ocaml/libs/xc/xenctrl.ml       |  1 +
 tools/ocaml/libs/xc/xenctrl.mli      |  1 +
 tools/xl/xl_parse.c                  |  2 ++
 xen/arch/arm/domain.c                | 10 ++++++++--
 xen/arch/arm/setup.c                 |  1 +
 xen/common/domain.c                  |  9 ++++++++-
 xen/include/asm-arm/domain.h         |  1 +
 xen/include/public/domctl.h          |  4 +++-
 14 files changed, 61 insertions(+), 4 deletions(-)

diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
index 4b1e3028d2..55c4881205 100644
--- a/docs/man/xl.cfg.5.pod.in
+++ b/docs/man/xl.cfg.5.pod.in
@@ -690,6 +690,23 @@ default.
 B<NOTE>: Acceptable values are platform specific.  For Intel Processor
 Trace, this value must be a power of 2 between 4k and 16M.
 
+=item B<vpmu=BOOLEAN>
+
+Currently ARM only.
+
+Specifies whether to enable the access to PMU registers by disabling
+the PMU traps.
+
+The PMU registers are not virtualized and the physical registers are directly
+accessible when this parameter is enabled. There is no interrupt support and
+Xen will not save/restore the register values on context switches.
+
+vPMU, by design and purpose, exposes system level performance
+information to the guest. Only to be used by sufficiently privileged
+domains. This feature is currently in experimental state.
+
+If this option is not specified then it will default to B<false>.
+
 =back
 
 =head2 Devices
diff --git a/tools/golang/xenlight/helpers.gen.go b/tools/golang/xenlight/helpers.gen.go
index c8669837d8..2449580bad 100644
--- a/tools/golang/xenlight/helpers.gen.go
+++ b/tools/golang/xenlight/helpers.gen.go
@@ -1119,6 +1119,9 @@ return fmt.Errorf("converting field ArchX86.MsrRelaxed: %v", err)
 }
 x.Altp2M = Altp2MMode(xc.altp2m)
 x.VmtraceBufKb = int(xc.vmtrace_buf_kb)
+if err := x.Vpmu.fromC(&xc.vpmu);err != nil {
+return fmt.Errorf("converting field Vpmu: %v", err)
+}
 
  return nil}
 
@@ -1600,6 +1603,9 @@ return fmt.Errorf("converting field ArchX86.MsrRelaxed: %v", err)
 }
 xc.altp2m = C.libxl_altp2m_mode(x.Altp2M)
 xc.vmtrace_buf_kb = C.int(x.VmtraceBufKb)
+if err := x.Vpmu.toC(&xc.vpmu); err != nil {
+return fmt.Errorf("converting field Vpmu: %v", err)
+}
 
  return nil
  }
diff --git a/tools/golang/xenlight/types.gen.go b/tools/golang/xenlight/types.gen.go
index 45f2cba3d2..b2e8bd1a85 100644
--- a/tools/golang/xenlight/types.gen.go
+++ b/tools/golang/xenlight/types.gen.go
@@ -521,6 +521,7 @@ MsrRelaxed Defbool
 }
 Altp2M Altp2MMode
 VmtraceBufKb int
+Vpmu Defbool
 }
 
 type DomainBuildInfoTypeUnion interface {
diff --git a/tools/include/libxl.h b/tools/include/libxl.h
index ec5e3badae..ee73eb06f1 100644
--- a/tools/include/libxl.h
+++ b/tools/include/libxl.h
@@ -508,6 +508,12 @@
  */
 #define LIBXL_HAVE_PHYSINFO_CAP_VPMU 1
 
+/*
+ * LIBXL_HAVE_VPMU indicates that libxl_domain_build_info has a vpmu parameter,
+ * which allows to enable the access to PMU registers.
+ */
+#define LIBXL_HAVE_VPMU 1
+
 /*
  * libxl ABI compatibility
  *
diff --git a/tools/libs/light/libxl_create.c b/tools/libs/light/libxl_create.c
index e356b2106d..d123c2f703 100644
--- a/tools/libs/light/libxl_create.c
+++ b/tools/libs/light/libxl_create.c
@@ -91,6 +91,7 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc,
     }
 
     libxl_defbool_setdefault(&b_info->device_model_stubdomain, false);
+    libxl_defbool_setdefault(&b_info->vpmu, false);
 
     if (libxl_defbool_val(b_info->device_model_stubdomain) &&
         !b_info->device_model_ssidref)
@@ -622,6 +623,9 @@ int libxl__domain_make(libxl__gc *gc, libxl_domain_config *d_config,
                 create.flags |= XEN_DOMCTL_CDF_nested_virt;
         }
 
+        if ( libxl_defbool_val(b_info->vpmu) )
+            create.flags |= XEN_DOMCTL_CDF_vpmu;
+
         assert(info->passthrough != LIBXL_PASSTHROUGH_DEFAULT);
         LOG(DETAIL, "passthrough: %s",
             libxl_passthrough_to_string(info->passthrough));
diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
index 993e83acca..b96fb5c47e 100644
--- a/tools/libs/light/libxl_types.idl
+++ b/tools/libs/light/libxl_types.idl
@@ -655,6 +655,8 @@ libxl_domain_build_info = Struct("domain_build_info",[
     # Use zero value to disable this feature.
     ("vmtrace_buf_kb", integer),
 
+    ("vpmu", libxl_defbool),
+
     ], dir=DIR_IN,
        copy_deprecated_fn="libxl__domain_build_info_copy_deprecated",
 )
diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
index 6da3ed3c6f..addcf4cc59 100644
--- a/tools/ocaml/libs/xc/xenctrl.ml
+++ b/tools/ocaml/libs/xc/xenctrl.ml
@@ -69,6 +69,7 @@ type domain_create_flag =
 	| CDF_XS_DOMAIN
 	| CDF_IOMMU
 	| CDF_NESTED_VIRT
+	| CDF_VPMU
 
 type domain_create_iommu_opts =
 	| IOMMU_NO_SHAREPT
diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
index b8faff6721..0a5ce529e9 100644
--- a/tools/ocaml/libs/xc/xenctrl.mli
+++ b/tools/ocaml/libs/xc/xenctrl.mli
@@ -62,6 +62,7 @@ type domain_create_flag =
   | CDF_XS_DOMAIN
   | CDF_IOMMU
   | CDF_NESTED_VIRT
+  | CDF_VPMU
 
 type domain_create_iommu_opts =
   | IOMMU_NO_SHAREPT
diff --git a/tools/xl/xl_parse.c b/tools/xl/xl_parse.c
index 17dddb4cd5..c503b9be00 100644
--- a/tools/xl/xl_parse.c
+++ b/tools/xl/xl_parse.c
@@ -2750,6 +2750,8 @@ skip_usbdev:
                     "If it fixes an issue you are having please report to "
                     "xen-devel@lists.xenproject.org.\n");
 
+    xlu_cfg_get_defbool(config, "vpmu", &b_info->vpmu, 0);
+
     xlu_cfg_destroy(config);
 }
 
diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 19c756ac3d..2dd474da09 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -276,6 +276,8 @@ static void ctxt_switch_to(struct vcpu *n)
      * timer. The interrupt needs to be injected into the guest. */
     WRITE_SYSREG(n->arch.cntkctl, CNTKCTL_EL1);
     virt_timer_restore(n);
+
+    WRITE_SYSREG(n->arch.mdcr_el2, MDCR_EL2);
 }
 
 /* Update per-VCPU guest runstate shared memory area (if registered). */
@@ -586,6 +588,10 @@ int arch_vcpu_create(struct vcpu *v)
 
     v->arch.hcr_el2 = get_default_hcr_flags();
 
+    v->arch.mdcr_el2 = HDCR_TDRA | HDCR_TDOSA | HDCR_TDA;
+    if ( !(v->domain->options & XEN_DOMCTL_CDF_vpmu) )
+        v->arch.mdcr_el2 |= HDCR_TPM | HDCR_TPMCR;
+
     if ( (rc = vcpu_vgic_init(v)) != 0 )
         goto fail;
 
@@ -622,8 +628,8 @@ int arch_sanitise_domain_config(struct xen_domctl_createdomain *config)
 {
     unsigned int max_vcpus;
 
-    /* HVM and HAP must be set. IOMMU may or may not be */
-    if ( (config->flags & ~XEN_DOMCTL_CDF_iommu) !=
+    /* HVM and HAP must be set. IOMMU and PMU may or may not be */
+    if ( (config->flags & ~(XEN_DOMCTL_CDF_iommu | XEN_DOMCTL_CDF_vpmu)) !=
          (XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap) )
     {
         dprintk(XENLOG_INFO, "Unsupported configuration %#x\n",
diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 49dc90d198..85386a765a 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -108,6 +108,7 @@ static void __init processor_id(void)
 
     identify_cpu(c);
     current_cpu_data = *c;
+    vpmu_is_available = cpu_has_pmu;
 
     if ( c->midr.implementer < ARRAY_SIZE(processor_implementers) &&
          processor_implementers[c->midr.implementer] )
diff --git a/xen/common/domain.c b/xen/common/domain.c
index 4d0e909eec..8b53c49d1e 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -480,12 +480,13 @@ static int sanitise_domain_config(struct xen_domctl_createdomain *config)
     bool hvm = config->flags & XEN_DOMCTL_CDF_hvm;
     bool hap = config->flags & XEN_DOMCTL_CDF_hap;
     bool iommu = config->flags & XEN_DOMCTL_CDF_iommu;
+    bool vpmu = config->flags & XEN_DOMCTL_CDF_vpmu;
 
     if ( config->flags &
          ~(XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap |
            XEN_DOMCTL_CDF_s3_integrity | XEN_DOMCTL_CDF_oos_off |
            XEN_DOMCTL_CDF_xs_domain | XEN_DOMCTL_CDF_iommu |
-           XEN_DOMCTL_CDF_nested_virt) )
+           XEN_DOMCTL_CDF_nested_virt | XEN_DOMCTL_CDF_vpmu) )
     {
         dprintk(XENLOG_INFO, "Unknown CDF flags %#x\n", config->flags);
         return -EINVAL;
@@ -534,6 +535,12 @@ static int sanitise_domain_config(struct xen_domctl_createdomain *config)
         return -EINVAL;
     }
 
+    if ( vpmu && !vpmu_is_available )
+    {
+        dprintk(XENLOG_INFO, "vpmu requested but cannot be enabled this way\n");
+        return -EINVAL;
+    }
+
     return arch_sanitise_domain_config(config);
 }
 
diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
index c9277b5c6d..14e575288f 100644
--- a/xen/include/asm-arm/domain.h
+++ b/xen/include/asm-arm/domain.h
@@ -166,6 +166,7 @@ struct arch_vcpu
 
     /* HYP configuration */
     register_t hcr_el2;
+    register_t mdcr_el2;
 
     uint32_t teecr, teehbr; /* ThumbEE, 32-bit guests only */
 #ifdef CONFIG_ARM_32
diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index 96696e3842..238384b5ae 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -70,9 +70,11 @@ struct xen_domctl_createdomain {
 #define XEN_DOMCTL_CDF_iommu          (1U<<_XEN_DOMCTL_CDF_iommu)
 #define _XEN_DOMCTL_CDF_nested_virt   6
 #define XEN_DOMCTL_CDF_nested_virt    (1U << _XEN_DOMCTL_CDF_nested_virt)
+/* Should we expose the vPMU to the guest? */
+#define XEN_DOMCTL_CDF_vpmu           (1U << 7)
 
 /* Max XEN_DOMCTL_CDF_* constant.  Used for ABI checking. */
-#define XEN_DOMCTL_CDF_MAX XEN_DOMCTL_CDF_nested_virt
+#define XEN_DOMCTL_CDF_MAX XEN_DOMCTL_CDF_vpmu
 
     uint32_t flags;
 
-- 
2.29.0

Re: [PATCH v3 3/3] xen: Expose the PMU to the guests

[Bertrand Marquis]

Hi Michal,

> On 8 Oct 2021, at 09:19, Michal Orzel <Michal.Orzel@arm.com> wrote:
> 
> Add parameter vpmu to xl domain configuration syntax
> to enable the access to PMU registers by disabling
> the PMU traps(currently only for ARM).
> 
> The current status is that the PMU registers are not
> virtualized and the physical registers are directly
> accessible when this parameter is enabled. There is no
> interrupt support and Xen will not save/restore the
> register values on context switches.
> 
> Please note that this feature is experimental.
> 
> Signed-off-by: Michal Orzel <michal.orzel@arm.com>
> Signed-off-by: Julien Grall <julien@xen.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>

Cheers
Bertrand

> ---
> Changes since v2:
> -remove redundant check from x86 code
> -do not define bit position and mask separately
> Changes since v1:
> -modify vpmu parameter to be common rather than arch specific
> ---
> docs/man/xl.cfg.5.pod.in             | 17 +++++++++++++++++
> tools/golang/xenlight/helpers.gen.go |  6 ++++++
> tools/golang/xenlight/types.gen.go   |  1 +
> tools/include/libxl.h                |  6 ++++++
> tools/libs/light/libxl_create.c      |  4 ++++
> tools/libs/light/libxl_types.idl     |  2 ++
> tools/ocaml/libs/xc/xenctrl.ml       |  1 +
> tools/ocaml/libs/xc/xenctrl.mli      |  1 +
> tools/xl/xl_parse.c                  |  2 ++
> xen/arch/arm/domain.c                | 10 ++++++++--
> xen/arch/arm/setup.c                 |  1 +
> xen/common/domain.c                  |  9 ++++++++-
> xen/include/asm-arm/domain.h         |  1 +
> xen/include/public/domctl.h          |  4 +++-
> 14 files changed, 61 insertions(+), 4 deletions(-)
> 
> diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
> index 4b1e3028d2..55c4881205 100644
> --- a/docs/man/xl.cfg.5.pod.in
> +++ b/docs/man/xl.cfg.5.pod.in
> @@ -690,6 +690,23 @@ default.
> B<NOTE>: Acceptable values are platform specific.  For Intel Processor
> Trace, this value must be a power of 2 between 4k and 16M.
> 
> +=item B<vpmu=BOOLEAN>
> +
> +Currently ARM only.
> +
> +Specifies whether to enable the access to PMU registers by disabling
> +the PMU traps.
> +
> +The PMU registers are not virtualized and the physical registers are directly
> +accessible when this parameter is enabled. There is no interrupt support and
> +Xen will not save/restore the register values on context switches.
> +
> +vPMU, by design and purpose, exposes system level performance
> +information to the guest. Only to be used by sufficiently privileged
> +domains. This feature is currently in experimental state.
> +
> +If this option is not specified then it will default to B<false>.
> +
> =back
> 
> =head2 Devices
> diff --git a/tools/golang/xenlight/helpers.gen.go b/tools/golang/xenlight/helpers.gen.go
> index c8669837d8..2449580bad 100644
> --- a/tools/golang/xenlight/helpers.gen.go
> +++ b/tools/golang/xenlight/helpers.gen.go
> @@ -1119,6 +1119,9 @@ return fmt.Errorf("converting field ArchX86.MsrRelaxed: %v", err)
> }
> x.Altp2M = Altp2MMode(xc.altp2m)
> x.VmtraceBufKb = int(xc.vmtrace_buf_kb)
> +if err := x.Vpmu.fromC(&xc.vpmu);err != nil {
> +return fmt.Errorf("converting field Vpmu: %v", err)
> +}
> 
>  return nil}
> 
> @@ -1600,6 +1603,9 @@ return fmt.Errorf("converting field ArchX86.MsrRelaxed: %v", err)
> }
> xc.altp2m = C.libxl_altp2m_mode(x.Altp2M)
> xc.vmtrace_buf_kb = C.int(x.VmtraceBufKb)
> +if err := x.Vpmu.toC(&xc.vpmu); err != nil {
> +return fmt.Errorf("converting field Vpmu: %v", err)
> +}
> 
>  return nil
>  }
> diff --git a/tools/golang/xenlight/types.gen.go b/tools/golang/xenlight/types.gen.go
> index 45f2cba3d2..b2e8bd1a85 100644
> --- a/tools/golang/xenlight/types.gen.go
> +++ b/tools/golang/xenlight/types.gen.go
> @@ -521,6 +521,7 @@ MsrRelaxed Defbool
> }
> Altp2M Altp2MMode
> VmtraceBufKb int
> +Vpmu Defbool
> }
> 
> type DomainBuildInfoTypeUnion interface {
> diff --git a/tools/include/libxl.h b/tools/include/libxl.h
> index ec5e3badae..ee73eb06f1 100644
> --- a/tools/include/libxl.h
> +++ b/tools/include/libxl.h
> @@ -508,6 +508,12 @@
>  */
> #define LIBXL_HAVE_PHYSINFO_CAP_VPMU 1
> 
> +/*
> + * LIBXL_HAVE_VPMU indicates that libxl_domain_build_info has a vpmu parameter,
> + * which allows to enable the access to PMU registers.
> + */
> +#define LIBXL_HAVE_VPMU 1
> +
> /*
>  * libxl ABI compatibility
>  *
> diff --git a/tools/libs/light/libxl_create.c b/tools/libs/light/libxl_create.c
> index e356b2106d..d123c2f703 100644
> --- a/tools/libs/light/libxl_create.c
> +++ b/tools/libs/light/libxl_create.c
> @@ -91,6 +91,7 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc,
>     }
> 
>     libxl_defbool_setdefault(&b_info->device_model_stubdomain, false);
> +    libxl_defbool_setdefault(&b_info->vpmu, false);
> 
>     if (libxl_defbool_val(b_info->device_model_stubdomain) &&
>         !b_info->device_model_ssidref)
> @@ -622,6 +623,9 @@ int libxl__domain_make(libxl__gc *gc, libxl_domain_config *d_config,
>                 create.flags |= XEN_DOMCTL_CDF_nested_virt;
>         }
> 
> +        if ( libxl_defbool_val(b_info->vpmu) )
> +            create.flags |= XEN_DOMCTL_CDF_vpmu;
> +
>         assert(info->passthrough != LIBXL_PASSTHROUGH_DEFAULT);
>         LOG(DETAIL, "passthrough: %s",
>             libxl_passthrough_to_string(info->passthrough));
> diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
> index 993e83acca..b96fb5c47e 100644
> --- a/tools/libs/light/libxl_types.idl
> +++ b/tools/libs/light/libxl_types.idl
> @@ -655,6 +655,8 @@ libxl_domain_build_info = Struct("domain_build_info",[
>     # Use zero value to disable this feature.
>     ("vmtrace_buf_kb", integer),
> 
> +    ("vpmu", libxl_defbool),
> +
>     ], dir=DIR_IN,
>        copy_deprecated_fn="libxl__domain_build_info_copy_deprecated",
> )
> diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
> index 6da3ed3c6f..addcf4cc59 100644
> --- a/tools/ocaml/libs/xc/xenctrl.ml
> +++ b/tools/ocaml/libs/xc/xenctrl.ml
> @@ -69,6 +69,7 @@ type domain_create_flag =
> 	| CDF_XS_DOMAIN
> 	| CDF_IOMMU
> 	| CDF_NESTED_VIRT
> +	| CDF_VPMU
> 
> type domain_create_iommu_opts =
> 	| IOMMU_NO_SHAREPT
> diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
> index b8faff6721..0a5ce529e9 100644
> --- a/tools/ocaml/libs/xc/xenctrl.mli
> +++ b/tools/ocaml/libs/xc/xenctrl.mli
> @@ -62,6 +62,7 @@ type domain_create_flag =
>   | CDF_XS_DOMAIN
>   | CDF_IOMMU
>   | CDF_NESTED_VIRT
> +  | CDF_VPMU
> 
> type domain_create_iommu_opts =
>   | IOMMU_NO_SHAREPT
> diff --git a/tools/xl/xl_parse.c b/tools/xl/xl_parse.c
> index 17dddb4cd5..c503b9be00 100644
> --- a/tools/xl/xl_parse.c
> +++ b/tools/xl/xl_parse.c
> @@ -2750,6 +2750,8 @@ skip_usbdev:
>                     "If it fixes an issue you are having please report to "
>                     "xen-devel@lists.xenproject.org.\n");
> 
> +    xlu_cfg_get_defbool(config, "vpmu", &b_info->vpmu, 0);
> +
>     xlu_cfg_destroy(config);
> }
> 
> diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
> index 19c756ac3d..2dd474da09 100644
> --- a/xen/arch/arm/domain.c
> +++ b/xen/arch/arm/domain.c
> @@ -276,6 +276,8 @@ static void ctxt_switch_to(struct vcpu *n)
>      * timer. The interrupt needs to be injected into the guest. */
>     WRITE_SYSREG(n->arch.cntkctl, CNTKCTL_EL1);
>     virt_timer_restore(n);
> +
> +    WRITE_SYSREG(n->arch.mdcr_el2, MDCR_EL2);
> }
> 
> /* Update per-VCPU guest runstate shared memory area (if registered). */
> @@ -586,6 +588,10 @@ int arch_vcpu_create(struct vcpu *v)
> 
>     v->arch.hcr_el2 = get_default_hcr_flags();
> 
> +    v->arch.mdcr_el2 = HDCR_TDRA | HDCR_TDOSA | HDCR_TDA;
> +    if ( !(v->domain->options & XEN_DOMCTL_CDF_vpmu) )
> +        v->arch.mdcr_el2 |= HDCR_TPM | HDCR_TPMCR;
> +
>     if ( (rc = vcpu_vgic_init(v)) != 0 )
>         goto fail;
> 
> @@ -622,8 +628,8 @@ int arch_sanitise_domain_config(struct xen_domctl_createdomain *config)
> {
>     unsigned int max_vcpus;
> 
> -    /* HVM and HAP must be set. IOMMU may or may not be */
> -    if ( (config->flags & ~XEN_DOMCTL_CDF_iommu) !=
> +    /* HVM and HAP must be set. IOMMU and PMU may or may not be */
> +    if ( (config->flags & ~(XEN_DOMCTL_CDF_iommu | XEN_DOMCTL_CDF_vpmu)) !=
>          (XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap) )
>     {
>         dprintk(XENLOG_INFO, "Unsupported configuration %#x\n",
> diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
> index 49dc90d198..85386a765a 100644
> --- a/xen/arch/arm/setup.c
> +++ b/xen/arch/arm/setup.c
> @@ -108,6 +108,7 @@ static void __init processor_id(void)
> 
>     identify_cpu(c);
>     current_cpu_data = *c;
> +    vpmu_is_available = cpu_has_pmu;
> 
>     if ( c->midr.implementer < ARRAY_SIZE(processor_implementers) &&
>          processor_implementers[c->midr.implementer] )
> diff --git a/xen/common/domain.c b/xen/common/domain.c
> index 4d0e909eec..8b53c49d1e 100644
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -480,12 +480,13 @@ static int sanitise_domain_config(struct xen_domctl_createdomain *config)
>     bool hvm = config->flags & XEN_DOMCTL_CDF_hvm;
>     bool hap = config->flags & XEN_DOMCTL_CDF_hap;
>     bool iommu = config->flags & XEN_DOMCTL_CDF_iommu;
> +    bool vpmu = config->flags & XEN_DOMCTL_CDF_vpmu;
> 
>     if ( config->flags &
>          ~(XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap |
>            XEN_DOMCTL_CDF_s3_integrity | XEN_DOMCTL_CDF_oos_off |
>            XEN_DOMCTL_CDF_xs_domain | XEN_DOMCTL_CDF_iommu |
> -           XEN_DOMCTL_CDF_nested_virt) )
> +           XEN_DOMCTL_CDF_nested_virt | XEN_DOMCTL_CDF_vpmu) )
>     {
>         dprintk(XENLOG_INFO, "Unknown CDF flags %#x\n", config->flags);
>         return -EINVAL;
> @@ -534,6 +535,12 @@ static int sanitise_domain_config(struct xen_domctl_createdomain *config)
>         return -EINVAL;
>     }
> 
> +    if ( vpmu && !vpmu_is_available )
> +    {
> +        dprintk(XENLOG_INFO, "vpmu requested but cannot be enabled this way\n");
> +        return -EINVAL;
> +    }
> +
>     return arch_sanitise_domain_config(config);
> }
> 
> diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
> index c9277b5c6d..14e575288f 100644
> --- a/xen/include/asm-arm/domain.h
> +++ b/xen/include/asm-arm/domain.h
> @@ -166,6 +166,7 @@ struct arch_vcpu
> 
>     /* HYP configuration */
>     register_t hcr_el2;
> +    register_t mdcr_el2;
> 
>     uint32_t teecr, teehbr; /* ThumbEE, 32-bit guests only */
> #ifdef CONFIG_ARM_32
> diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
> index 96696e3842..238384b5ae 100644
> --- a/xen/include/public/domctl.h
> +++ b/xen/include/public/domctl.h
> @@ -70,9 +70,11 @@ struct xen_domctl_createdomain {
> #define XEN_DOMCTL_CDF_iommu          (1U<<_XEN_DOMCTL_CDF_iommu)
> #define _XEN_DOMCTL_CDF_nested_virt   6
> #define XEN_DOMCTL_CDF_nested_virt    (1U << _XEN_DOMCTL_CDF_nested_virt)
> +/* Should we expose the vPMU to the guest? */
> +#define XEN_DOMCTL_CDF_vpmu           (1U << 7)
> 
> /* Max XEN_DOMCTL_CDF_* constant.  Used for ABI checking. */
> -#define XEN_DOMCTL_CDF_MAX XEN_DOMCTL_CDF_nested_virt
> +#define XEN_DOMCTL_CDF_MAX XEN_DOMCTL_CDF_vpmu
> 
>     uint32_t flags;
> 
> -- 
> 2.29.0
> 
> 

Re: [PATCH v3 3/3] xen: Expose the PMU to the guests

[Nick Rosbrook]

On Fri, Oct 08, 2021 at 10:19:33AM +0200, Michal Orzel wrote:
> Add parameter vpmu to xl domain configuration syntax
> to enable the access to PMU registers by disabling
> the PMU traps(currently only for ARM).
> 
> The current status is that the PMU registers are not
> virtualized and the physical registers are directly
> accessible when this parameter is enabled. There is no
> interrupt support and Xen will not save/restore the
> register values on context switches.
> 
> Please note that this feature is experimental.
> 
> Signed-off-by: Michal Orzel <michal.orzel@arm.com>
> Signed-off-by: Julien Grall <julien@xen.org>
> ---
> Changes since v2:
> -remove redundant check from x86 code
> -do not define bit position and mask separately
> Changes since v1:
> -modify vpmu parameter to be common rather than arch specific
> ---
>  docs/man/xl.cfg.5.pod.in             | 17 +++++++++++++++++
>  tools/golang/xenlight/helpers.gen.go |  6 ++++++
>  tools/golang/xenlight/types.gen.go   |  1 +
>  tools/include/libxl.h                |  6 ++++++
>  tools/libs/light/libxl_create.c      |  4 ++++
>  tools/libs/light/libxl_types.idl     |  2 ++
>  tools/ocaml/libs/xc/xenctrl.ml       |  1 +
>  tools/ocaml/libs/xc/xenctrl.mli      |  1 +
>  tools/xl/xl_parse.c                  |  2 ++
>  xen/arch/arm/domain.c                | 10 ++++++++--
>  xen/arch/arm/setup.c                 |  1 +
>  xen/common/domain.c                  |  9 ++++++++-
>  xen/include/asm-arm/domain.h         |  1 +
>  xen/include/public/domctl.h          |  4 +++-
>  14 files changed, 61 insertions(+), 4 deletions(-)
> 
> diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
> index 4b1e3028d2..55c4881205 100644
> --- a/docs/man/xl.cfg.5.pod.in
> +++ b/docs/man/xl.cfg.5.pod.in
> @@ -690,6 +690,23 @@ default.
>  B<NOTE>: Acceptable values are platform specific.  For Intel Processor
>  Trace, this value must be a power of 2 between 4k and 16M.
>  
> +=item B<vpmu=BOOLEAN>
> +
> +Currently ARM only.
> +
> +Specifies whether to enable the access to PMU registers by disabling
> +the PMU traps.
> +
> +The PMU registers are not virtualized and the physical registers are directly
> +accessible when this parameter is enabled. There is no interrupt support and
> +Xen will not save/restore the register values on context switches.
> +
> +vPMU, by design and purpose, exposes system level performance
> +information to the guest. Only to be used by sufficiently privileged
> +domains. This feature is currently in experimental state.
> +
> +If this option is not specified then it will default to B<false>.
> +
>  =back
>  
>  =head2 Devices
> diff --git a/tools/golang/xenlight/helpers.gen.go b/tools/golang/xenlight/helpers.gen.go
> index c8669837d8..2449580bad 100644
> --- a/tools/golang/xenlight/helpers.gen.go
> +++ b/tools/golang/xenlight/helpers.gen.go
> @@ -1119,6 +1119,9 @@ return fmt.Errorf("converting field ArchX86.MsrRelaxed: %v", err)
>  }
>  x.Altp2M = Altp2MMode(xc.altp2m)
>  x.VmtraceBufKb = int(xc.vmtrace_buf_kb)
> +if err := x.Vpmu.fromC(&xc.vpmu);err != nil {
> +return fmt.Errorf("converting field Vpmu: %v", err)
> +}
>  
>   return nil}
>  
> @@ -1600,6 +1603,9 @@ return fmt.Errorf("converting field ArchX86.MsrRelaxed: %v", err)
>  }
>  xc.altp2m = C.libxl_altp2m_mode(x.Altp2M)
>  xc.vmtrace_buf_kb = C.int(x.VmtraceBufKb)
> +if err := x.Vpmu.toC(&xc.vpmu); err != nil {
> +return fmt.Errorf("converting field Vpmu: %v", err)
> +}
>  
>   return nil
>   }
> diff --git a/tools/golang/xenlight/types.gen.go b/tools/golang/xenlight/types.gen.go
> index 45f2cba3d2..b2e8bd1a85 100644
> --- a/tools/golang/xenlight/types.gen.go
> +++ b/tools/golang/xenlight/types.gen.go
> @@ -521,6 +521,7 @@ MsrRelaxed Defbool
>  }
>  Altp2M Altp2MMode
>  VmtraceBufKb int
> +Vpmu Defbool
>  }
>  
>  type DomainBuildInfoTypeUnion interface {

For the golang re-gen,

Acked-by: Nick Rosbrook <rosbrookn@ainfosec.com>

Thanks,
NR

Re: [PATCH v3 3/3] xen: Expose the PMU to the guests

[Stefano Stabellini]

On Fri, 8 Oct 2021, Michal Orzel wrote:
> Add parameter vpmu to xl domain configuration syntax
> to enable the access to PMU registers by disabling
> the PMU traps(currently only for ARM).
> 
> The current status is that the PMU registers are not
> virtualized and the physical registers are directly
> accessible when this parameter is enabled. There is no
> interrupt support and Xen will not save/restore the
> register values on context switches.
> 
> Please note that this feature is experimental.
> 
> Signed-off-by: Michal Orzel <michal.orzel@arm.com>
> Signed-off-by: Julien Grall <julien@xen.org>

The patch needs rebasing


> ---
> Changes since v2:
> -remove redundant check from x86 code
> -do not define bit position and mask separately
> Changes since v1:
> -modify vpmu parameter to be common rather than arch specific
> ---
>  docs/man/xl.cfg.5.pod.in             | 17 +++++++++++++++++
>  tools/golang/xenlight/helpers.gen.go |  6 ++++++
>  tools/golang/xenlight/types.gen.go   |  1 +
>  tools/include/libxl.h                |  6 ++++++
>  tools/libs/light/libxl_create.c      |  4 ++++
>  tools/libs/light/libxl_types.idl     |  2 ++
>  tools/ocaml/libs/xc/xenctrl.ml       |  1 +
>  tools/ocaml/libs/xc/xenctrl.mli      |  1 +
>  tools/xl/xl_parse.c                  |  2 ++
>  xen/arch/arm/domain.c                | 10 ++++++++--
>  xen/arch/arm/setup.c                 |  1 +
>  xen/common/domain.c                  |  9 ++++++++-
>  xen/include/asm-arm/domain.h         |  1 +
>  xen/include/public/domctl.h          |  4 +++-
>  14 files changed, 61 insertions(+), 4 deletions(-)
> 
> diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
> index 4b1e3028d2..55c4881205 100644
> --- a/docs/man/xl.cfg.5.pod.in
> +++ b/docs/man/xl.cfg.5.pod.in
> @@ -690,6 +690,23 @@ default.
>  B<NOTE>: Acceptable values are platform specific.  For Intel Processor
>  Trace, this value must be a power of 2 between 4k and 16M.
>  
> +=item B<vpmu=BOOLEAN>
> +
> +Currently ARM only.
> +
> +Specifies whether to enable the access to PMU registers by disabling
> +the PMU traps.
> +
> +The PMU registers are not virtualized and the physical registers are directly
> +accessible when this parameter is enabled. There is no interrupt support and
> +Xen will not save/restore the register values on context switches.
> +
> +vPMU, by design and purpose, exposes system level performance
> +information to the guest. Only to be used by sufficiently privileged
> +domains. This feature is currently in experimental state.
> +
> +If this option is not specified then it will default to B<false>.
> +
>  =back
>  
>  =head2 Devices
> diff --git a/tools/golang/xenlight/helpers.gen.go b/tools/golang/xenlight/helpers.gen.go
> index c8669837d8..2449580bad 100644
> --- a/tools/golang/xenlight/helpers.gen.go
> +++ b/tools/golang/xenlight/helpers.gen.go
> @@ -1119,6 +1119,9 @@ return fmt.Errorf("converting field ArchX86.MsrRelaxed: %v", err)
>  }
>  x.Altp2M = Altp2MMode(xc.altp2m)
>  x.VmtraceBufKb = int(xc.vmtrace_buf_kb)
> +if err := x.Vpmu.fromC(&xc.vpmu);err != nil {
> +return fmt.Errorf("converting field Vpmu: %v", err)
> +}
>  
>   return nil}
>  
> @@ -1600,6 +1603,9 @@ return fmt.Errorf("converting field ArchX86.MsrRelaxed: %v", err)
>  }
>  xc.altp2m = C.libxl_altp2m_mode(x.Altp2M)
>  xc.vmtrace_buf_kb = C.int(x.VmtraceBufKb)
> +if err := x.Vpmu.toC(&xc.vpmu); err != nil {
> +return fmt.Errorf("converting field Vpmu: %v", err)
> +}
>  
>   return nil
>   }
> diff --git a/tools/golang/xenlight/types.gen.go b/tools/golang/xenlight/types.gen.go
> index 45f2cba3d2..b2e8bd1a85 100644
> --- a/tools/golang/xenlight/types.gen.go
> +++ b/tools/golang/xenlight/types.gen.go
> @@ -521,6 +521,7 @@ MsrRelaxed Defbool
>  }
>  Altp2M Altp2MMode
>  VmtraceBufKb int
> +Vpmu Defbool
>  }
>  
>  type DomainBuildInfoTypeUnion interface {
> diff --git a/tools/include/libxl.h b/tools/include/libxl.h
> index ec5e3badae..ee73eb06f1 100644
> --- a/tools/include/libxl.h
> +++ b/tools/include/libxl.h
> @@ -508,6 +508,12 @@
>   */
>  #define LIBXL_HAVE_PHYSINFO_CAP_VPMU 1
>  
> +/*
> + * LIBXL_HAVE_VPMU indicates that libxl_domain_build_info has a vpmu parameter,
> + * which allows to enable the access to PMU registers.
> + */
> +#define LIBXL_HAVE_VPMU 1
> +
>  /*
>   * libxl ABI compatibility
>   *
> diff --git a/tools/libs/light/libxl_create.c b/tools/libs/light/libxl_create.c
> index e356b2106d..d123c2f703 100644
> --- a/tools/libs/light/libxl_create.c
> +++ b/tools/libs/light/libxl_create.c
> @@ -91,6 +91,7 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc,
>      }
>  
>      libxl_defbool_setdefault(&b_info->device_model_stubdomain, false);
> +    libxl_defbool_setdefault(&b_info->vpmu, false);
>  
>      if (libxl_defbool_val(b_info->device_model_stubdomain) &&
>          !b_info->device_model_ssidref)
> @@ -622,6 +623,9 @@ int libxl__domain_make(libxl__gc *gc, libxl_domain_config *d_config,
>                  create.flags |= XEN_DOMCTL_CDF_nested_virt;
>          }
>  
> +        if ( libxl_defbool_val(b_info->vpmu) )
> +            create.flags |= XEN_DOMCTL_CDF_vpmu;

As Andrew recently pointed out in another thread
(https://marc.info/?l=xen-devel&m=163372953907637), it would be good to
check that vpmu is actually available from Xen before setting
XEN_DOMCTL_CDF_vpmu. You have already added XEN_SYSCTL_PHYSCAP_vpmu in
patch #1, so it should be only a matter of checking for it.

So that we can fail explicitly if vpmu is set in the config file but
XEN_SYSCTL_PHYSCAP_vpmu is not available.

Everything else looks fine to me.



>          assert(info->passthrough != LIBXL_PASSTHROUGH_DEFAULT);
>          LOG(DETAIL, "passthrough: %s",
>              libxl_passthrough_to_string(info->passthrough));
> diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
> index 993e83acca..b96fb5c47e 100644
> --- a/tools/libs/light/libxl_types.idl
> +++ b/tools/libs/light/libxl_types.idl
> @@ -655,6 +655,8 @@ libxl_domain_build_info = Struct("domain_build_info",[
>      # Use zero value to disable this feature.
>      ("vmtrace_buf_kb", integer),
>  
> +    ("vpmu", libxl_defbool),
> +
>      ], dir=DIR_IN,
>         copy_deprecated_fn="libxl__domain_build_info_copy_deprecated",
>  )
> diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
> index 6da3ed3c6f..addcf4cc59 100644
> --- a/tools/ocaml/libs/xc/xenctrl.ml
> +++ b/tools/ocaml/libs/xc/xenctrl.ml
> @@ -69,6 +69,7 @@ type domain_create_flag =
>  	| CDF_XS_DOMAIN
>  	| CDF_IOMMU
>  	| CDF_NESTED_VIRT
> +	| CDF_VPMU
>  
>  type domain_create_iommu_opts =
>  	| IOMMU_NO_SHAREPT
> diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
> index b8faff6721..0a5ce529e9 100644
> --- a/tools/ocaml/libs/xc/xenctrl.mli
> +++ b/tools/ocaml/libs/xc/xenctrl.mli
> @@ -62,6 +62,7 @@ type domain_create_flag =
>    | CDF_XS_DOMAIN
>    | CDF_IOMMU
>    | CDF_NESTED_VIRT
> +  | CDF_VPMU
>  
>  type domain_create_iommu_opts =
>    | IOMMU_NO_SHAREPT
> diff --git a/tools/xl/xl_parse.c b/tools/xl/xl_parse.c
> index 17dddb4cd5..c503b9be00 100644
> --- a/tools/xl/xl_parse.c
> +++ b/tools/xl/xl_parse.c
> @@ -2750,6 +2750,8 @@ skip_usbdev:
>                      "If it fixes an issue you are having please report to "
>                      "xen-devel@lists.xenproject.org.\n");
>  
> +    xlu_cfg_get_defbool(config, "vpmu", &b_info->vpmu, 0);
> +
>      xlu_cfg_destroy(config);
>  }
>  
> diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
> index 19c756ac3d..2dd474da09 100644
> --- a/xen/arch/arm/domain.c
> +++ b/xen/arch/arm/domain.c
> @@ -276,6 +276,8 @@ static void ctxt_switch_to(struct vcpu *n)
>       * timer. The interrupt needs to be injected into the guest. */
>      WRITE_SYSREG(n->arch.cntkctl, CNTKCTL_EL1);
>      virt_timer_restore(n);
> +
> +    WRITE_SYSREG(n->arch.mdcr_el2, MDCR_EL2);
>  }
>  
>  /* Update per-VCPU guest runstate shared memory area (if registered). */
> @@ -586,6 +588,10 @@ int arch_vcpu_create(struct vcpu *v)
>  
>      v->arch.hcr_el2 = get_default_hcr_flags();
>  
> +    v->arch.mdcr_el2 = HDCR_TDRA | HDCR_TDOSA | HDCR_TDA;
> +    if ( !(v->domain->options & XEN_DOMCTL_CDF_vpmu) )
> +        v->arch.mdcr_el2 |= HDCR_TPM | HDCR_TPMCR;
> +
>      if ( (rc = vcpu_vgic_init(v)) != 0 )
>          goto fail;
>  
> @@ -622,8 +628,8 @@ int arch_sanitise_domain_config(struct xen_domctl_createdomain *config)
>  {
>      unsigned int max_vcpus;
>  
> -    /* HVM and HAP must be set. IOMMU may or may not be */
> -    if ( (config->flags & ~XEN_DOMCTL_CDF_iommu) !=
> +    /* HVM and HAP must be set. IOMMU and PMU may or may not be */
> +    if ( (config->flags & ~(XEN_DOMCTL_CDF_iommu | XEN_DOMCTL_CDF_vpmu)) !=
>           (XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap) )
>      {
>          dprintk(XENLOG_INFO, "Unsupported configuration %#x\n",
> diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
> index 49dc90d198..85386a765a 100644
> --- a/xen/arch/arm/setup.c
> +++ b/xen/arch/arm/setup.c
> @@ -108,6 +108,7 @@ static void __init processor_id(void)
>  
>      identify_cpu(c);
>      current_cpu_data = *c;
> +    vpmu_is_available = cpu_has_pmu;
>  
>      if ( c->midr.implementer < ARRAY_SIZE(processor_implementers) &&
>           processor_implementers[c->midr.implementer] )
> diff --git a/xen/common/domain.c b/xen/common/domain.c
> index 4d0e909eec..8b53c49d1e 100644
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -480,12 +480,13 @@ static int sanitise_domain_config(struct xen_domctl_createdomain *config)
>      bool hvm = config->flags & XEN_DOMCTL_CDF_hvm;
>      bool hap = config->flags & XEN_DOMCTL_CDF_hap;
>      bool iommu = config->flags & XEN_DOMCTL_CDF_iommu;
> +    bool vpmu = config->flags & XEN_DOMCTL_CDF_vpmu;
>  
>      if ( config->flags &
>           ~(XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap |
>             XEN_DOMCTL_CDF_s3_integrity | XEN_DOMCTL_CDF_oos_off |
>             XEN_DOMCTL_CDF_xs_domain | XEN_DOMCTL_CDF_iommu |
> -           XEN_DOMCTL_CDF_nested_virt) )
> +           XEN_DOMCTL_CDF_nested_virt | XEN_DOMCTL_CDF_vpmu) )
>      {
>          dprintk(XENLOG_INFO, "Unknown CDF flags %#x\n", config->flags);
>          return -EINVAL;
> @@ -534,6 +535,12 @@ static int sanitise_domain_config(struct xen_domctl_createdomain *config)
>          return -EINVAL;
>      }
>  
> +    if ( vpmu && !vpmu_is_available )
> +    {
> +        dprintk(XENLOG_INFO, "vpmu requested but cannot be enabled this way\n");
> +        return -EINVAL;
> +    }
> +
>      return arch_sanitise_domain_config(config);
>  }
>  
> diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
> index c9277b5c6d..14e575288f 100644
> --- a/xen/include/asm-arm/domain.h
> +++ b/xen/include/asm-arm/domain.h
> @@ -166,6 +166,7 @@ struct arch_vcpu
>  
>      /* HYP configuration */
>      register_t hcr_el2;
> +    register_t mdcr_el2;
>  
>      uint32_t teecr, teehbr; /* ThumbEE, 32-bit guests only */
>  #ifdef CONFIG_ARM_32
> diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
> index 96696e3842..238384b5ae 100644
> --- a/xen/include/public/domctl.h
> +++ b/xen/include/public/domctl.h
> @@ -70,9 +70,11 @@ struct xen_domctl_createdomain {
>  #define XEN_DOMCTL_CDF_iommu          (1U<<_XEN_DOMCTL_CDF_iommu)
>  #define _XEN_DOMCTL_CDF_nested_virt   6
>  #define XEN_DOMCTL_CDF_nested_virt    (1U << _XEN_DOMCTL_CDF_nested_virt)
> +/* Should we expose the vPMU to the guest? */
> +#define XEN_DOMCTL_CDF_vpmu           (1U << 7)
>  
>  /* Max XEN_DOMCTL_CDF_* constant.  Used for ABI checking. */
> -#define XEN_DOMCTL_CDF_MAX XEN_DOMCTL_CDF_nested_virt
> +#define XEN_DOMCTL_CDF_MAX XEN_DOMCTL_CDF_vpmu
>  
>      uint32_t flags;
>  
> -- 
> 2.29.0
>