diff mbox series

[05/21] libs/guest: introduce helper to fetch a domain cpu policy

Message ID 20210323095849.37858-6-roger.pau@citrix.com (mailing list archive)
State Superseded
Headers show
Series libs/guest: new CPUID/MSR interface | expand

Commit Message

Roger Pau Monne March 23, 2021, 9:58 a.m. UTC
Such helper is based on the existing functions to fetch a CPUID and
MSR policies, but uses the xc_cpu_policy_t type to return the data to
the caller.

No user of the interface introduced on the patch.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
---
 tools/include/xenctrl.h         |  2 ++
 tools/libs/guest/xg_cpuid_x86.c | 34 +++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+)

Comments

Jan Beulich March 30, 2021, 3:37 p.m. UTC | #1
On 23.03.2021 10:58, Roger Pau Monne wrote:
> Such helper is based on the existing functions to fetch a CPUID and
> MSR policies, but uses the xc_cpu_policy_t type to return the data to
> the caller.
> 
> No user of the interface introduced on the patch.
> 
> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>

Reviewed-by: Jan Beulich <jbeulich@suse.com>
with again a minor remark (plus of course the same that I made for
patch 4):

> --- a/tools/include/xenctrl.h
> +++ b/tools/include/xenctrl.h
> @@ -2599,6 +2599,8 @@ void xc_cpu_policy_destroy(xc_cpu_policy_t policy);
>  /* Retrieve a system policy, or get/set a domains policy. */
>  int xc_cpu_policy_get_system(xc_interface *xch, unsigned int idx,
>                               xc_cpu_policy_t policy);
> +int xc_cpu_policy_get_domain(xc_interface *xch, uint32_t domid,
> +                             xc_cpu_policy_t policy);

Generally I'd expect domid_t to be used for domain IDs.

Jan
Roger Pau Monne March 31, 2021, 11:06 a.m. UTC | #2
On Tue, Mar 30, 2021 at 05:37:02PM +0200, Jan Beulich wrote:
> On 23.03.2021 10:58, Roger Pau Monne wrote:
> > Such helper is based on the existing functions to fetch a CPUID and
> > MSR policies, but uses the xc_cpu_policy_t type to return the data to
> > the caller.
> > 
> > No user of the interface introduced on the patch.
> > 
> > Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
> 
> Reviewed-by: Jan Beulich <jbeulich@suse.com>
> with again a minor remark (plus of course the same that I made for
> patch 4):
> 
> > --- a/tools/include/xenctrl.h
> > +++ b/tools/include/xenctrl.h
> > @@ -2599,6 +2599,8 @@ void xc_cpu_policy_destroy(xc_cpu_policy_t policy);
> >  /* Retrieve a system policy, or get/set a domains policy. */
> >  int xc_cpu_policy_get_system(xc_interface *xch, unsigned int idx,
> >                               xc_cpu_policy_t policy);
> > +int xc_cpu_policy_get_domain(xc_interface *xch, uint32_t domid,
> > +                             xc_cpu_policy_t policy);
> 
> Generally I'd expect domid_t to be used for domain IDs.

Me too, but xenctrl.h seems to consistently use uint32_t for domain
ids. I'm fine to use domid_t here, but I assumed there was a reason
for using uint32_t uniformly there.

Thanks, Roger.
Andrew Cooper April 1, 2021, 1:32 p.m. UTC | #3
On 31/03/2021 12:06, Roger Pau Monné wrote:
> On Tue, Mar 30, 2021 at 05:37:02PM +0200, Jan Beulich wrote:
>> On 23.03.2021 10:58, Roger Pau Monne wrote:
>>> Such helper is based on the existing functions to fetch a CPUID and
>>> MSR policies, but uses the xc_cpu_policy_t type to return the data to
>>> the caller.
>>>
>>> No user of the interface introduced on the patch.
>>>
>>> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
>> Reviewed-by: Jan Beulich <jbeulich@suse.com>
>> with again a minor remark (plus of course the same that I made for
>> patch 4):
>>
>>> --- a/tools/include/xenctrl.h
>>> +++ b/tools/include/xenctrl.h
>>> @@ -2599,6 +2599,8 @@ void xc_cpu_policy_destroy(xc_cpu_policy_t policy);
>>>  /* Retrieve a system policy, or get/set a domains policy. */
>>>  int xc_cpu_policy_get_system(xc_interface *xch, unsigned int idx,
>>>                               xc_cpu_policy_t policy);
>>> +int xc_cpu_policy_get_domain(xc_interface *xch, uint32_t domid,
>>> +                             xc_cpu_policy_t policy);
>> Generally I'd expect domid_t to be used for domain IDs.
> Me too, but xenctrl.h seems to consistently use uint32_t for domain
> ids. I'm fine to use domid_t here, but I assumed there was a reason
> for using uint32_t uniformly there.

There was a tools-wide change making everything uint32_t a while ago,
but libxc itself has never used domid_t.  IIRC, it was to do with
problems concerning the INVALID_DOMID constant.

~Andrew
diff mbox series

Patch

diff --git a/tools/include/xenctrl.h b/tools/include/xenctrl.h
index fc8e4b28781..8b8b30a2764 100644
--- a/tools/include/xenctrl.h
+++ b/tools/include/xenctrl.h
@@ -2599,6 +2599,8 @@  void xc_cpu_policy_destroy(xc_cpu_policy_t policy);
 /* Retrieve a system policy, or get/set a domains policy. */
 int xc_cpu_policy_get_system(xc_interface *xch, unsigned int idx,
                              xc_cpu_policy_t policy);
+int xc_cpu_policy_get_domain(xc_interface *xch, uint32_t domid,
+                             xc_cpu_policy_t policy);
 
 int xc_get_cpu_levelling_caps(xc_interface *xch, uint32_t *caps);
 int xc_get_cpu_featureset(xc_interface *xch, uint32_t index,
diff --git a/tools/libs/guest/xg_cpuid_x86.c b/tools/libs/guest/xg_cpuid_x86.c
index 3710fb63839..75ac70996ac 100644
--- a/tools/libs/guest/xg_cpuid_x86.c
+++ b/tools/libs/guest/xg_cpuid_x86.c
@@ -777,3 +777,37 @@  int xc_cpu_policy_get_system(xc_interface *xch, unsigned int idx,
     free(msrs);
     return rc;
 }
+
+int xc_cpu_policy_get_domain(xc_interface *xch, uint32_t domid,
+                             xc_cpu_policy_t policy)
+{
+    unsigned int nr_leaves, nr_msrs;
+    xen_cpuid_leaf_t *leaves = NULL;
+    xen_msr_entry_t *msrs = NULL;
+    int rc;
+
+    rc = allocate_buffers(xch, &nr_leaves, &leaves, &nr_msrs, &msrs);
+    if ( rc )
+    {
+        errno = -rc;
+        return -1;
+    }
+
+    rc = xc_get_domain_cpu_policy(xch, domid, &nr_leaves, leaves, &nr_msrs,
+                                  msrs);
+    if ( rc )
+    {
+        PERROR("Failed to obtain domain %u policy", domid);
+        rc = -1;
+        goto out;
+    }
+
+    rc = deserialize_policy(xch, policy, nr_leaves, leaves, nr_msrs, msrs);
+    if ( rc )
+        errno = -rc;
+
+ out:
+    free(leaves);
+    free(msrs);
+    return rc;
+}