Re: [kvm-unit-tests patch v6 08/18] x86: pmu: Fix cycles event validation failure

[Mi, Dapeng]

On 2/15/2025 5:07 AM, Sean Christopherson wrote:
> On Sat, Sep 14, 2024, Dapeng Mi wrote:
>> +static void warm_up(void)
>> +{
>> +	int i = 8;
>> +
>> +	/*
>> +	 * Since cycles event is always run as the first event, there would be
>> +	 * a warm-up state to warm up the cache, it leads to the measured cycles
>> +	 * value may exceed the pre-defined cycles upper boundary and cause
>> +	 * false positive. To avoid this, introduce an warm-up state before
>> +	 * the real verification.
>> +	 */
>> +	while (i--)
>> +		loop();
> Use a for-loop.

Sure.


>
>> +}
>> +
>>  static void check_counters(void)
>>  {
>>  	if (is_fep_available())
>>  		check_emulated_instr();
>>  
>> +	warm_up();
>>  	check_gp_counters();
>>  	check_fixed_counters();
>>  	check_rdpmc();
>> -- 
>> 2.40.1
>>