Re: [kvm-unit-tests PATCH v2 3/3] x86: Skip perf related tests when pmu is disabled

["Yang, Weijiang" <weijiang.yang@intel.com>]

On 6/17/2022 2:40 AM, Sean Christopherson wrote:
> On Wed, Jun 15, 2022, Yang Weijiang wrote:
>> When pmu is disabled in KVM, reading MSR_CORE_PERF_GLOBAL_CTRL
>> or executing rdpmc leads to #GP, so skip related tests in this case.
>>
>> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
>> ---
>>   x86/vmx_tests.c | 24 ++++++++++++++++++++++++
>>   1 file changed, 24 insertions(+)
>>
>> diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
>> index 4d581e7..dd6fc13 100644
>> --- a/x86/vmx_tests.c
>> +++ b/x86/vmx_tests.c
>> @@ -944,6 +944,16 @@ static void insn_intercept_main(void)
>>   			continue;
>>   		}
>>   
>> +		if (insn_table[cur_insn].flag == CPU_RDPMC) {
>> +			struct cpuid id = cpuid(10);
>> +
>> +			if (!(id.a & 0xff)) {
> Please add helpers to query (a) the PMU version and (b) whether or not PERF_GLOBAL_CTRL
> is supported.
Sure.
>
>> +				printf("\tFeature required for %s is not supported.\n",
>> +				       insn_table[cur_insn].name);
>> +				continue;
>> +			}
>> +		}
>> +
>>   		if (insn_table[cur_insn].disabled) {
>>   			printf("\tFeature required for %s is not supported.\n",
>>   			       insn_table[cur_insn].name);
>> @@ -7490,6 +7500,13 @@ static void test_perf_global_ctrl(u32 nr, const char *name, u32 ctrl_nr,
>>   
>>   static void test_load_host_perf_global_ctrl(void)
>>   {
>> +	struct cpuid id = cpuid(10);
>> +
>> +	if (!(id.a & 0xff)) {
>> +		report_skip("test_load_host_perf_global_ctrl");
>> +		return;
>> +	}
>> +
>>   	if (!(ctrl_exit_rev.clr & EXI_LOAD_PERF)) {
>>   		printf("\"load IA32_PERF_GLOBAL_CTRL\" exit control not supported\n");
>>   		return;
>> @@ -7502,6 +7519,13 @@ static void test_load_host_perf_global_ctrl(void)
>>   
>>   static void test_load_guest_perf_global_ctrl(void)
>>   {
>> +	struct cpuid id = cpuid(10);
>> +
>> +	if (!(id.a & 0xff)) {
>> +		report_skip("test_load_guest_perf_global_ctrl");
>> +		return;
>> +	}
>> +
>>   	if (!(ctrl_enter_rev.clr & ENT_LOAD_PERF)) {
>>   		printf("\"load IA32_PERF_GLOBAL_CTRL\" entry control not supported\n");
>>   		return;
>> -- 
>> 2.31.1
>>