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[PATCH 2/6] KVM: x86: selftests: Define AMD PMU CPUID leaves

Colton Lewis posted 6 patches 1 year, 6 months ago
There is a newer version of this series
[PATCH 2/6] KVM: x86: selftests: Define AMD PMU CPUID leaves
Posted by Colton Lewis 1 year, 6 months ago 
This defined the CPUID calls to determine what extensions and
properties are available. AMD reference manual names listed below.

* PerfCtrExtCore (six core counters instead of four)
* PerfCtrExtNB (four counters for northbridge events)
* PerfCtrExtL2I (four counters for L2 cache events)
* PerfMonV2 (support for registers to control multiple
  counters with a single register write)
* LbrAndPmcFreeze (support for freezing last branch recorded stack on
  performance counter overflow)
* NumPerfCtrCore (number of core counters)
* NumPerfCtrNB (number of northbridge counters)

Signed-off-by: Colton Lewis <coltonlewis@google.com>
---
 tools/testing/selftests/kvm/include/x86_64/processor.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index a0c1440017bb..9d87b5f8974f 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -183,6 +183,9 @@ struct kvm_x86_cpu_feature {
 #define	X86_FEATURE_GBPAGES		KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 26)
 #define	X86_FEATURE_RDTSCP		KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 27)
 #define	X86_FEATURE_LM			KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 29)
+#define	X86_FEATURE_PERF_CTR_EXT_CORE	KVM_X86_CPU_FEATURE(0x80000001, 0, ECX, 23)
+#define	X86_FEATURE_PERF_CTR_EXT_NB	KVM_X86_CPU_FEATURE(0x80000001, 0, ECX, 24)
+#define	X86_FEATURE_PERF_CTR_EXT_L2I	KVM_X86_CPU_FEATURE(0x80000001, 0, ECX, 28)
 #define	X86_FEATURE_INVTSC		KVM_X86_CPU_FEATURE(0x80000007, 0, EDX, 8)
 #define	X86_FEATURE_RDPRU		KVM_X86_CPU_FEATURE(0x80000008, 0, EBX, 4)
 #define	X86_FEATURE_AMD_IBPB		KVM_X86_CPU_FEATURE(0x80000008, 0, EBX, 12)
@@ -195,6 +198,8 @@ struct kvm_x86_cpu_feature {
 #define	X86_FEATURE_VGIF		KVM_X86_CPU_FEATURE(0x8000000A, 0, EDX, 16)
 #define X86_FEATURE_SEV			KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 1)
 #define X86_FEATURE_SEV_ES		KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 3)
+#define	X86_FEATURE_PERF_MON_V2		KVM_X86_CPU_FEATURE(0x80000022, 0, EAX, 0)
+#define	X86_FEATURE_PERF_LBR_PMC_FREEZE	KVM_X86_CPU_FEATURE(0x80000022, 0, EAX, 2)
 
 /*
  * KVM defined paravirt features.
@@ -281,6 +286,8 @@ struct kvm_x86_cpu_property {
 #define X86_PROPERTY_GUEST_MAX_PHY_ADDR		KVM_X86_CPU_PROPERTY(0x80000008, 0, EAX, 16, 23)
 #define X86_PROPERTY_SEV_C_BIT			KVM_X86_CPU_PROPERTY(0x8000001F, 0, EBX, 0, 5)
 #define X86_PROPERTY_PHYS_ADDR_REDUCTION	KVM_X86_CPU_PROPERTY(0x8000001F, 0, EBX, 6, 11)
+#define X86_PROPERTY_NUM_PERF_CTR_CORE		KVM_X86_CPU_PROPERTY(0x80000022, 0, EBX, 0, 3)
+#define X86_PROPERTY_NUM_PERF_CTR_NB		KVM_X86_CPU_PROPERTY(0x80000022, 0, EBX, 10, 15)
 
 #define X86_PROPERTY_MAX_CENTAUR_LEAF		KVM_X86_CPU_PROPERTY(0xC0000000, 0, EAX, 0, 31)
 
-- 
2.46.0.76.ge559c4bf1a-goog
Re: [PATCH 2/6] KVM: x86: selftests: Define AMD PMU CPUID leaves
Posted by Mingwei Zhang 1 year, 5 months ago 
On Tue, Aug 13, 2024, Colton Lewis wrote:
> This defined the CPUID calls to determine what extensions and
> properties are available. AMD reference manual names listed below.
> 
> * PerfCtrExtCore (six core counters instead of four)
> * PerfCtrExtNB (four counters for northbridge events)
> * PerfCtrExtL2I (four counters for L2 cache events)
> * PerfMonV2 (support for registers to control multiple
>   counters with a single register write)
> * LbrAndPmcFreeze (support for freezing last branch recorded stack on
>   performance counter overflow)
> * NumPerfCtrCore (number of core counters)
> * NumPerfCtrNB (number of northbridge counters)
> 
> Signed-off-by: Colton Lewis <coltonlewis@google.com>
> ---
>  tools/testing/selftests/kvm/include/x86_64/processor.h | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
> index a0c1440017bb..9d87b5f8974f 100644
> --- a/tools/testing/selftests/kvm/include/x86_64/processor.h
> +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
> @@ -183,6 +183,9 @@ struct kvm_x86_cpu_feature {
>  #define	X86_FEATURE_GBPAGES		KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 26)
>  #define	X86_FEATURE_RDTSCP		KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 27)
>  #define	X86_FEATURE_LM			KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 29)
> +#define	X86_FEATURE_PERF_CTR_EXT_CORE	KVM_X86_CPU_FEATURE(0x80000001, 0, ECX, 23)
> +#define	X86_FEATURE_PERF_CTR_EXT_NB	KVM_X86_CPU_FEATURE(0x80000001, 0, ECX, 24)
> +#define	X86_FEATURE_PERF_CTR_EXT_L2I	KVM_X86_CPU_FEATURE(0x80000001, 0, ECX, 28)

You won't be testing Northbridge counters and L2I counters, so these two
could be optional to the patch.
>  #define	X86_FEATURE_INVTSC		KVM_X86_CPU_FEATURE(0x80000007, 0, EDX, 8)
>  #define	X86_FEATURE_RDPRU		KVM_X86_CPU_FEATURE(0x80000008, 0, EBX, 4)
>  #define	X86_FEATURE_AMD_IBPB		KVM_X86_CPU_FEATURE(0x80000008, 0, EBX, 12)
> @@ -195,6 +198,8 @@ struct kvm_x86_cpu_feature {
>  #define	X86_FEATURE_VGIF		KVM_X86_CPU_FEATURE(0x8000000A, 0, EDX, 16)
>  #define X86_FEATURE_SEV			KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 1)
>  #define X86_FEATURE_SEV_ES		KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 3)
> +#define	X86_FEATURE_PERF_MON_V2		KVM_X86_CPU_FEATURE(0x80000022, 0, EAX, 0)

Let's use X86_FEATURE_PERFMON_V2 instead.

> +#define	X86_FEATURE_PERF_LBR_PMC_FREEZE	KVM_X86_CPU_FEATURE(0x80000022, 0, EAX, 2)

You don't use this feature, do you? If not, this can be optional for the
patch.
>  
>  /*
>   * KVM defined paravirt features.
> @@ -281,6 +286,8 @@ struct kvm_x86_cpu_property {
>  #define X86_PROPERTY_GUEST_MAX_PHY_ADDR		KVM_X86_CPU_PROPERTY(0x80000008, 0, EAX, 16, 23)
>  #define X86_PROPERTY_SEV_C_BIT			KVM_X86_CPU_PROPERTY(0x8000001F, 0, EBX, 0, 5)
>  #define X86_PROPERTY_PHYS_ADDR_REDUCTION	KVM_X86_CPU_PROPERTY(0x8000001F, 0, EBX, 6, 11)
> +#define X86_PROPERTY_NUM_PERF_CTR_CORE		KVM_X86_CPU_PROPERTY(0x80000022, 0, EBX, 0, 3)
> +#define X86_PROPERTY_NUM_PERF_CTR_NB		KVM_X86_CPU_PROPERTY(0x80000022, 0, EBX, 10, 15)
>  

ditto.
>  #define X86_PROPERTY_MAX_CENTAUR_LEAF		KVM_X86_CPU_PROPERTY(0xC0000000, 0, EAX, 0, 31)
>  
> -- 
> 2.46.0.76.ge559c4bf1a-goog
>
Re: [PATCH 2/6] KVM: x86: selftests: Define AMD PMU CPUID leaves
Posted by Colton Lewis 1 year, 5 months ago 
Hi Mingwei, thanks for reviewing!

Mingwei Zhang <mizhang@google.com> writes:

> On Tue, Aug 13, 2024, Colton Lewis wrote:
>> This defined the CPUID calls to determine what extensions and
>> properties are available. AMD reference manual names listed below.

>> * PerfCtrExtCore (six core counters instead of four)
>> * PerfCtrExtNB (four counters for northbridge events)
>> * PerfCtrExtL2I (four counters for L2 cache events)
>> * PerfMonV2 (support for registers to control multiple
>>    counters with a single register write)
>> * LbrAndPmcFreeze (support for freezing last branch recorded stack on
>>    performance counter overflow)
>> * NumPerfCtrCore (number of core counters)
>> * NumPerfCtrNB (number of northbridge counters)

>> Signed-off-by: Colton Lewis <coltonlewis@google.com>
>> ---
>>   tools/testing/selftests/kvm/include/x86_64/processor.h | 7 +++++++
>>   1 file changed, 7 insertions(+)

>> diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h  
>> b/tools/testing/selftests/kvm/include/x86_64/processor.h
>> index a0c1440017bb..9d87b5f8974f 100644
>> --- a/tools/testing/selftests/kvm/include/x86_64/processor.h
>> +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
>> @@ -183,6 +183,9 @@ struct kvm_x86_cpu_feature {
>>   #define	X86_FEATURE_GBPAGES		KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 26)
>>   #define	X86_FEATURE_RDTSCP		KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 27)
>>   #define	X86_FEATURE_LM			KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 29)
>> +#define	X86_FEATURE_PERF_CTR_EXT_CORE	KVM_X86_CPU_FEATURE(0x80000001,  
>> 0, ECX, 23)
>> +#define	X86_FEATURE_PERF_CTR_EXT_NB	KVM_X86_CPU_FEATURE(0x80000001, 0,  
>> ECX, 24)
>> +#define	X86_FEATURE_PERF_CTR_EXT_L2I	KVM_X86_CPU_FEATURE(0x80000001, 0,  
>> ECX, 28)

> You won't be testing Northbridge counters and L2I counters, so these two
> could be optional to the patch.

That's correct. Since it was a small thing to include I thought it best
to include and save someone in the future from digging through the
reference manual again.

When you say "optional" is that an endorsement of deleting?

>>   #define	X86_FEATURE_INVTSC		KVM_X86_CPU_FEATURE(0x80000007, 0, EDX, 8)
>>   #define	X86_FEATURE_RDPRU		KVM_X86_CPU_FEATURE(0x80000008, 0, EBX, 4)
>>   #define	X86_FEATURE_AMD_IBPB		KVM_X86_CPU_FEATURE(0x80000008, 0, EBX,  
>> 12)
>> @@ -195,6 +198,8 @@ struct kvm_x86_cpu_feature {
>>   #define	X86_FEATURE_VGIF		KVM_X86_CPU_FEATURE(0x8000000A, 0, EDX, 16)
>>   #define X86_FEATURE_SEV			KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 1)
>>   #define X86_FEATURE_SEV_ES		KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 3)
>> +#define	X86_FEATURE_PERF_MON_V2		KVM_X86_CPU_FEATURE(0x80000022, 0,  
>> EAX, 0)

> Let's use X86_FEATURE_PERFMON_V2 instead.

Done

>> +#define	X86_FEATURE_PERF_LBR_PMC_FREEZE	KVM_X86_CPU_FEATURE(0x80000022,  
>> 0, EAX, 2)

> You don't use this feature, do you? If not, this can be optional for the
> patch.

Correct again, included for the same reasoning above.


>>   /*
>>    * KVM defined paravirt features.
>> @@ -281,6 +286,8 @@ struct kvm_x86_cpu_property {
>>   #define X86_PROPERTY_GUEST_MAX_PHY_ADDR		 
>> KVM_X86_CPU_PROPERTY(0x80000008, 0, EAX, 16, 23)
>>   #define X86_PROPERTY_SEV_C_BIT			KVM_X86_CPU_PROPERTY(0x8000001F, 0,  
>> EBX, 0, 5)
>>   #define X86_PROPERTY_PHYS_ADDR_REDUCTION	 
>> KVM_X86_CPU_PROPERTY(0x8000001F, 0, EBX, 6, 11)
>> +#define X86_PROPERTY_NUM_PERF_CTR_CORE		 
>> KVM_X86_CPU_PROPERTY(0x80000022, 0, EBX, 0, 3)
>> +#define X86_PROPERTY_NUM_PERF_CTR_NB		KVM_X86_CPU_PROPERTY(0x80000022,  
>> 0, EBX, 10, 15)


> ditto.
>>   #define X86_PROPERTY_MAX_CENTAUR_LEAF		KVM_X86_CPU_PROPERTY(0xC0000000,  
>> 0, EAX, 0, 31)

>> --
>> 2.46.0.76.ge559c4bf1a-goog
Re: [PATCH 2/6] KVM: x86: selftests: Define AMD PMU CPUID leaves
Posted by Sean Christopherson 1 year, 5 months ago 
On Wed, Aug 28, 2024, Colton Lewis wrote:
> Hi Mingwei, thanks for reviewing!
> 
> Mingwei Zhang <mizhang@google.com> writes:
> 
> > On Tue, Aug 13, 2024, Colton Lewis wrote:
> > > This defined the CPUID calls to determine what extensions and
> > > properties are available. AMD reference manual names listed below.
> 
> > > * PerfCtrExtCore (six core counters instead of four)
> > > * PerfCtrExtNB (four counters for northbridge events)
> > > * PerfCtrExtL2I (four counters for L2 cache events)
> > > * PerfMonV2 (support for registers to control multiple
> > >    counters with a single register write)
> > > * LbrAndPmcFreeze (support for freezing last branch recorded stack on
> > >    performance counter overflow)
> > > * NumPerfCtrCore (number of core counters)
> > > * NumPerfCtrNB (number of northbridge counters)
> 
> > > Signed-off-by: Colton Lewis <coltonlewis@google.com>
> > > ---
> > >   tools/testing/selftests/kvm/include/x86_64/processor.h | 7 +++++++
> > >   1 file changed, 7 insertions(+)
> 
> > > diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h
> > > b/tools/testing/selftests/kvm/include/x86_64/processor.h
> > > index a0c1440017bb..9d87b5f8974f 100644
> > > --- a/tools/testing/selftests/kvm/include/x86_64/processor.h
> > > +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
> > > @@ -183,6 +183,9 @@ struct kvm_x86_cpu_feature {
> > >   #define	X86_FEATURE_GBPAGES		KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 26)
> > >   #define	X86_FEATURE_RDTSCP		KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 27)
> > >   #define	X86_FEATURE_LM			KVM_X86_CPU_FEATURE(0x80000001, 0, EDX, 29)
> > > +#define	X86_FEATURE_PERF_CTR_EXT_CORE	KVM_X86_CPU_FEATURE(0x80000001,
> > > 0, ECX, 23)
> > > +#define	X86_FEATURE_PERF_CTR_EXT_NB	KVM_X86_CPU_FEATURE(0x80000001,
> > > 0, ECX, 24)
> > > +#define	X86_FEATURE_PERF_CTR_EXT_L2I	KVM_X86_CPU_FEATURE(0x80000001,
> > > 0, ECX, 28)
> 
> > You won't be testing Northbridge counters and L2I counters, so these two
> > could be optional to the patch.
> 
> That's correct. Since it was a small thing to include I thought it best
> to include and save someone in the future from digging through the
> reference manual again.

+1.  They're defines, i.e. have no meaningful cost.  And anything that *might*
save me from having to find CPUID entries in the SDM/APM is worth adding.

Patchew 2.1-devel-b67e4c2

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