| Message ID | 20211129153355.60338-6-roger.pau@citrix.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | libs/guest: new CPUID/MSR interface | expand |
On 29.11.2021 16:33, Roger Pau Monne wrote: > --- a/tools/libs/guest/xg_cpuid_x86.c > +++ b/tools/libs/guest/xg_cpuid_x86.c > @@ -878,6 +878,26 @@ int xc_cpu_policy_get_cpuid(xc_interface *xch, const xc_cpu_policy_t *policy, > return 0; > } > > +int xc_cpu_policy_get_msr(xc_interface *xch, const xc_cpu_policy_t *policy, > + uint32_t msr, xen_msr_entry_t *out) > +{ > + const uint64_t *val; > + > + *out = (xen_msr_entry_t){}; Unless there's a specific reason for the divergence, this just-in- case initialization should imo be consistently there (or absent) in both the MSR and the CPUID function. Jan
On Mon, Dec 06, 2021 at 04:27:25PM +0100, Jan Beulich wrote: > On 29.11.2021 16:33, Roger Pau Monne wrote: > > --- a/tools/libs/guest/xg_cpuid_x86.c > > +++ b/tools/libs/guest/xg_cpuid_x86.c > > @@ -878,6 +878,26 @@ int xc_cpu_policy_get_cpuid(xc_interface *xch, const xc_cpu_policy_t *policy, > > return 0; > > } > > > > +int xc_cpu_policy_get_msr(xc_interface *xch, const xc_cpu_policy_t *policy, > > + uint32_t msr, xen_msr_entry_t *out) > > +{ > > + const uint64_t *val; > > + > > + *out = (xen_msr_entry_t){}; > > Unless there's a specific reason for the divergence, this just-in- > case initialization should imo be consistently there (or absent) > in both the MSR and the CPUID function. Right - will add the initialization to the CPUID function. Thanks, Roger.
diff --git a/tools/include/xenguest.h b/tools/include/xenguest.h index 0a6fd99306..2672fd043c 100644 --- a/tools/include/xenguest.h +++ b/tools/include/xenguest.h @@ -810,6 +810,8 @@ int xc_cpu_policy_update_msrs(xc_interface *xch, xc_cpu_policy_t *policy, int xc_cpu_policy_get_cpuid(xc_interface *xch, const xc_cpu_policy_t *policy, uint32_t leaf, uint32_t subleaf, xen_cpuid_leaf_t *out); +int xc_cpu_policy_get_msr(xc_interface *xch, const xc_cpu_policy_t *policy, + uint32_t msr, xen_msr_entry_t *out); /* Compatibility calculations. */ bool xc_cpu_policy_is_compatible(xc_interface *xch, xc_cpu_policy_t *host, diff --git a/tools/libs/guest/xg_cpuid_x86.c b/tools/libs/guest/xg_cpuid_x86.c index 7779a3e1dd..859c885c15 100644 --- a/tools/libs/guest/xg_cpuid_x86.c +++ b/tools/libs/guest/xg_cpuid_x86.c @@ -878,6 +878,26 @@ int xc_cpu_policy_get_cpuid(xc_interface *xch, const xc_cpu_policy_t *policy, return 0; } +int xc_cpu_policy_get_msr(xc_interface *xch, const xc_cpu_policy_t *policy, + uint32_t msr, xen_msr_entry_t *out) +{ + const uint64_t *val; + + *out = (xen_msr_entry_t){}; + + val = x86_msr_get_entry(&policy->msr, msr); + if ( !val ) + { + errno = ENOENT; + return -1; + } + + out->idx = msr; + out->val = *val; + + return 0; +} + bool xc_cpu_policy_is_compatible(xc_interface *xch, xc_cpu_policy_t *host, xc_cpu_policy_t *guest) {
Introduce an interface that returns a specific MSR entry from a cpu policy in xen_msr_entry_t format. This is useful to callers can peek data from the opaque xc_cpu_policy_t type. No caller of the interface introduced on this patch. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> --- Changes since v3: - Use x86_msr_get_entry. Changes since v1: - Introduce a helper to perform a binary search of the MSR entries array. --- tools/include/xenguest.h | 2 ++ tools/libs/guest/xg_cpuid_x86.c | 20 ++++++++++++++++++++ 2 files changed, 22 insertions(+)