Re: [PATCH i-g-t] tests/xe_gt_freq: Avoid RPe usage in subtests

[Riana Tauro <riana.tauro@intel.com>]

Hi Vinay

On 7/26/2024 10:38 AM, Nilawar, Badal wrote:
> Hi Vinay,
> 
> On 24-07-2024 22:29, Vinay Belgaumkar wrote:
>> We are seeing several instances where the RPe, which can be altered by
>> pcode dynamically, is causing subtests to fail randomly. Instead of 
>> relying
>> on it, we can use a mid frequency value for these subtests and avoid 
>> these
>> failures.
>>
>> Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2262
>> Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2256
>>
>> Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
>> ---
>>   tests/intel/xe_gt_freq.c | 37 +++++++++++++++++++++++++++++--------
>>   1 file changed, 29 insertions(+), 8 deletions(-)
>>
>> diff --git a/tests/intel/xe_gt_freq.c b/tests/intel/xe_gt_freq.c
>> index 93ebb5ed0..442f5658f 100644
>> --- a/tests/intel/xe_gt_freq.c
>> +++ b/tests/intel/xe_gt_freq.c
>> @@ -26,6 +26,9 @@
>>   #include <sys/time.h>
>>   #define MAX_N_EXEC_QUEUES 16
>> +#define GT_FREQUENCY_MULTIPLIER    50
>> +#define GT_FREQUENCY_SCALER    3
>> +#define FREQ_UNIT_MHZ (GT_FREQUENCY_MULTIPLIER / GT_FREQUENCY_SCALER)
>>   /*
>>    * Too many intermediate components and steps before freq is adjusted
>> @@ -70,6 +73,16 @@ static uint32_t get_freq(int fd, int gt_id, const 
>> char *freq_name)
>>       return freq;
>>   }
>> +static bool within_expected_range(uint32_t freq, uint32_t val)
>> +{
>> +    /*
>> +     * GT Frequencies are requested at units of 16.66 Mhz, so allow
>> +     * that tolerance.
>> +     */
>> +    return (freq <= val + FREQ_UNIT_MHZ) ||
>> +        (freq >= val - FREQ_UNIT_MHZ);
>> +}
>> +
>>   static uint32_t rpe(int fd, int gt_id)
>>   {
>>       return get_freq(fd, gt_id, "rpe");
>> @@ -128,6 +141,8 @@ static void test_freq_basic_api(int fd, int gt_id)
This test doesn't need the current rpe since it only sets min and max to 
rpe and reads it back.

We could use the previous saved value here
>>   {
>>       uint32_t rpn = get_freq(fd, gt_id, "rpn");
>>       uint32_t rp0 = get_freq(fd, gt_id, "rp0");
>> +    uint32_t rpmid = (rp0 + rpn) / 2;
>> +    uint32_t min_freq, max_freq;
>>       /*
>>        * Negative bound tests
>> @@ -142,16 +157,18 @@ static void test_freq_basic_api(int fd, int gt_id)
>>       /* Assert min requests are respected from rp0 to rpn */
>>       igt_assert(set_freq(fd, gt_id, "min", rp0) > 0);
>>       igt_assert(get_freq(fd, gt_id, "min") == rp0);
>> -    igt_assert(set_freq(fd, gt_id, "min", rpe(fd, gt_id)) > 0);
>> -    igt_assert(get_freq(fd, gt_id, "min") == rpe(fd, gt_id));
>> +    igt_assert(set_freq(fd, gt_id, "min", rpmid) > 0);
>> +    min_freq = get_freq(fd, gt_id, "min");
>> +    igt_assert(within_expected_range(min_freq, rpmid));
>>       igt_assert(set_freq(fd, gt_id, "min", rpn) > 0);
>>       igt_assert(get_freq(fd, gt_id, "min") == rpn);
>>       /* Assert max requests are respected from rpn to rp0 */
>>       igt_assert(set_freq(fd, gt_id, "max", rpn) > 0);
>>       igt_assert(get_freq(fd, gt_id, "max") == rpn);
>> -    igt_assert(set_freq(fd, gt_id, "max", rpe(fd, gt_id)) > 0);
>> -    igt_assert(get_freq(fd, gt_id, "max") == rpe(fd, gt_id));
>> +    igt_assert(set_freq(fd, gt_id, "max", rpmid) > 0);
>> +    max_freq = get_freq(fd, gt_id, "min");
get_freq(fd, gt_id, "max")
>> +    igt_assert(within_expected_range(max_freq, rpmid));
>>       igt_assert(set_freq(fd, gt_id, "max", rp0) > 0);
>>       igt_assert(get_freq(fd, gt_id, "max") == rp0);
>>   }
>> @@ -168,6 +185,8 @@ static void test_freq_fixed(int fd, int gt_id, 
>> bool gt_idle)
>>   {
>>       uint32_t rpn = get_freq(fd, gt_id, "rpn");
>>       uint32_t rp0 = get_freq(fd, gt_id, "rp0");
>> +    uint32_t rpmid = (rp0 + rpn) / 2;
>> +    uint32_t cur_freq, act_freq;
>>       igt_debug("Starting testing fixed request\n");
>> @@ -190,17 +209,19 @@ static void test_freq_fixed(int fd, int gt_id, 
>> bool gt_idle)


The comment in this test needs to be modified since we are not using Rpe 
here anymore


/*
  * For Fixed freq we need to set both min and max to the desired value
  * Then we check if hardware is actually operating at the desired freq
  * And let's do this for all the 3 known Render Performance (RP) values.
  */

Thanks,
Riana

>>           igt_assert(get_freq(fd, gt_id, "act") == rpn);
>>       }
>> -    igt_assert(set_freq(fd, gt_id, "min", rpe(fd, gt_id)) > 0);
>> -    igt_assert(set_freq(fd, gt_id, "max", rpe(fd, gt_id)) > 0);
>> +    igt_assert(set_freq(fd, gt_id, "min", rpmid) > 0);
>> +    igt_assert(set_freq(fd, gt_id, "max", rpmid) > 0);
>>       usleep(ACT_FREQ_LATENCY_US);
>> -    igt_assert(get_freq(fd, gt_id, "cur") == rpe(fd, gt_id));
>> +    cur_freq = get_freq(fd, gt_id, "cur");
>> +    igt_assert(within_expected_range(cur_freq, rpmid));
>>       if (gt_idle) {
>>           igt_assert_f(igt_wait(xe_is_gt_in_c6(fd, gt_id), 1000, 10),
>>                    "GT %d should be in C6\n", gt_id);
>>           igt_assert(get_freq(fd, gt_id, "act") == 0);
>>       } else {
>> -        igt_assert(get_freq(fd, gt_id, "act") == rpe(fd, gt_id));
>> +        act_freq = get_freq(fd, gt_id, "act");
>> +        igt_assert(within_expected_range(act_freq, rpmid));
>>       }
>>       igt_assert(set_freq(fd, gt_id, "min", rp0) > 0);
> 
> We should cover freq range subtests as well.
> 
> https://intel-gfx-ci.01.org/tree/intel-xe/xe-1667-9f8e597a1c39d7e316f9479e6f627c15dbc58e1d/shard-lnl-7/igt@xe_gt_freq@freq_range_exec.html
> 
> Regards,
> Badal