Re: [igt-dev] [PATCH i-g-t] test/perf_pmu: Dump drpc on C6 failure

["Nilawar, Badal" <badal.nilawar@intel.com>]

On 02-08-2023 15:08, Riana Tauro wrote:
> 
> 
> On 8/2/2023 3:06 PM, Riana Tauro wrote:
>> Hi Anshuman
>>
>> On 8/1/2023 6:55 PM, Anshuman Gupta wrote:
>>> Dump drpc debugfs on RC6/MC6 failure, it will be useful to
>>> debug any C6 failure issue by using drpc debugfs debug info.
>>>
>>> Co-developed-by: Badal Nilawar <badal.nilawar@intel.com>
>>> Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
>>> ---
>>>   tests/i915/perf_pmu.c | 61 +++++++++++++++++++++++++++++--------------
>>>   1 file changed, 42 insertions(+), 19 deletions(-)
>>>
>>> diff --git a/tests/i915/perf_pmu.c b/tests/i915/perf_pmu.c
>>> index 58f4a82a2..bcd6db799 100644
>>> --- a/tests/i915/perf_pmu.c
>>> +++ b/tests/i915/perf_pmu.c
>>> @@ -256,6 +256,18 @@ IGT_TEST_DESCRIPTION("Test the i915 pmu perf 
>>> interface");
>>>   const double tolerance = 0.05f;
>>>   const unsigned long batch_duration_ns = 500e6;
>>> +char *drpc;
>>> +const char *no_debug_data = "\0";
>>> +
>>> +static char *get_drpc(int i915, int gt_id)
>>> +{
>>> +    int gt_dir;
>>> +
>>> +    gt_dir = igt_debugfs_gt_dir(i915, gt_id);
>>> +    igt_assert(gt_dir != -1);
>>> +    return igt_sysfs_get(gt_dir, "drpc");
>>> +}
>>> +
>>>   static int open_pmu(int i915, uint64_t config)
>>>   {
>>>       int fd;
>>> @@ -336,17 +348,19 @@ static uint64_t pmu_read_multi(int fd, unsigned 
>>> int num, uint64_t *val)
>>>       return buf[1];
>>>   }
>>> -#define __assert_within_epsilon(x, ref, tol_up, tol_down) \
>>> +#define __assert_within_epsilon(x, ref, tol_up, tol_down, debug_data) \
>>>       igt_assert_f((double)(x) <= (1.0 + (tol_up)) * (double)(ref) && \
>>>                (double)(x) >= (1.0 - (tol_down)) * (double)(ref), \
>>> -             "'%s' != '%s' (%f not within +%.1f%%/-%.1f%% tolerance 
>>> of %f)\n",\
>>> +             "'%s' != '%s' (%f not within +%.1f%%/-%.1f%% tolerance 
>>> of %f)\n%s\n",\
>>>                #x, #ref, (double)(x), \
>>>                (tol_up) * 100.0, (tol_down) * 100.0, \
>>> -             (double)(ref))
>>> +             (double)(ref), debug_data)
>>>   #define assert_within_epsilon(x, ref, tolerance) \
>>> -    __assert_within_epsilon(x, ref, tolerance, tolerance)
>>> +    __assert_within_epsilon(x, ref, tolerance, tolerance, "\0")
> no_debug_data can be used here
>>> +#define assert_within_epsilon_dump(x, ref, tolerance, debug_data) \
>>> +    __assert_within_epsilon(x, ref, tolerance, tolerance, debug_data)
>> debug instead of dump?
>>>   /*
>>>    * Helper for cases where we assert on time spent sleeping 
>>> (directly or
>>>    * indirectly), so make it more robust by ensuring the system sleep 
>>> time
>>> @@ -1822,7 +1836,7 @@ test_frequency(int gem_fd, unsigned int gt)
>>>        * On thermally throttled devices we cannot be sure maximum 
>>> frequency
>>>        * can be reached so use larger tolerance downards.
>>>        */
>>> -    __assert_within_epsilon(max[0], max_freq, tolerance, 0.15f);
>>> +    __assert_within_epsilon(max[0], max_freq, tolerance, 0.15f, 
>>> no_debug_data);
>>>   }
>>>   static void
>>> @@ -1967,7 +1981,8 @@ test_rc6(int gem_fd, unsigned int gt, unsigned 
>>> int num_gt, unsigned int flags)
>>>           }
>>>       }
>>> -    igt_require(wait_for_rc6(fd[0], 1, pmus, test_idx));
>>> +    igt_require_f(wait_for_rc6(fd[0], 1, pmus, test_idx),
>>> +              "failed to enter rc6/mc6 \n%s\n", drpc = 
>>> get_drpc(gem_fd, test_idx));
>> test_idx is assigned to pmus in this function. Safer to use gt.
test_idx indicate gt under test so it is ok to use test_idx here.

Regards,
Badal
>>
>> Thanks
>> Riana
>>>       /* While idle check full RC6. */
>>>       ts[0] = pmu_read_multi(fd[0], pmus, prev);
>>> @@ -1977,9 +1992,11 @@ test_rc6(int gem_fd, unsigned int gt, unsigned 
>>> int num_gt, unsigned int flags)
>>>       for (gt_ = 0; gt_ < pmus; gt_++) {
>>>           igt_debug("gt%u: idle rc6=%"PRIu64", slept=%lu, 
>>> perf=%"PRIu64"\n",
>>>                 gt_, idle[gt_] - prev[gt_], slept, ts[1] - ts[0]);
>>> -        assert_within_epsilon(idle[gt_] - prev[gt_],
>>> -                      ts[1] - ts[0],
>>> -                      tolerance);
>>> +        drpc = get_drpc(gem_fd, gt_);
>>> +        assert_within_epsilon_dump(idle[gt_] - prev[gt_],
>>> +                       ts[1] - ts[0],
>>> +                       tolerance, drpc);
>>> +        free(drpc);
>>>       }
>>>       if (flags & TEST_S3) {
>>> @@ -2005,7 +2022,8 @@ test_rc6(int gem_fd, unsigned int gt, unsigned 
>>> int num_gt, unsigned int flags)
>>>           }
>>>       }
>>> -    igt_assert(wait_for_rc6(fd[0], 5, pmus, test_idx));
>>> +    igt_require_f(wait_for_rc6(fd[0], 5, pmus, test_idx),
>>> +              "failed to enter rc6/mc6 \n%s\n", drpc = 
>>> get_drpc(gem_fd, test_idx));
>>>       ts[0] = pmu_read_multi(fd[0], pmus, prev);
>>>       slept = measured_usleep(duration_ns / 1000);
>>> @@ -2014,9 +2032,11 @@ test_rc6(int gem_fd, unsigned int gt, unsigned 
>>> int num_gt, unsigned int flags)
>>>       for (gt_ = 0; gt_ < pmus; gt_++) {
>>>           igt_debug("gt%u: idle rc6=%"PRIu64", slept=%lu, 
>>> perf=%"PRIu64"\n",
>>>                 gt_, idle[gt_] - prev[gt_], slept, ts[1] - ts[0]);
>>> -        assert_within_epsilon(idle[gt_] - prev[gt_],
>>> -                      ts[1] - ts[0],
>>> -                      tolerance);
>>> +        drpc = get_drpc(gem_fd, gt_);
>>> +        assert_within_epsilon_dump(idle[gt_] - prev[gt_],
>>> +                       ts[1] - ts[0],
>>> +                       tolerance, drpc);
>>> +        free(drpc);
>>>       }
>>>       /* Wake up device and check no RC6. */
>>> @@ -2048,14 +2068,16 @@ test_rc6(int gem_fd, unsigned int gt, 
>>> unsigned int num_gt, unsigned int flags)
>>>       for (gt_ = 0; gt_ < pmus; gt_++) {
>>>           igt_debug("gt%u: busy rc6=%"PRIu64", slept=%lu, 
>>> perf=%"PRIu64"\n",
>>>                 gt_, busy[gt_] - prev[gt_], slept, ts[1] - ts[0]);
>>> +        drpc = get_drpc(gem_fd, gt_);
>>>           if (gt_ == test_idx || (flags & TEST_ALL))
>>> -            assert_within_epsilon(busy[gt_] - prev[gt_],
>>> -                          0.0,
>>> -                          tolerance);
>>> +            assert_within_epsilon_dump(busy[gt_] - prev[gt_],
>>> +                           0.0,
>>> +                           tolerance, drpc);
>>>           else
>>> -            assert_within_epsilon(busy[gt_] - prev[gt_],
>>> -                          ts[1] - ts[0],
>>> -                          tolerance);
>>> +            assert_within_epsilon_dump(busy[gt_] - prev[gt_],
>>> +                           ts[1] - ts[0],
>>> +                           tolerance, drpc);
>>> +        free(drpc);
>>>       }
>>>   }
>>> @@ -2720,6 +2742,7 @@ igt_main
>>>       igt_fixture {
>>>           intel_ctx_destroy(fd, ctx);
>>>           drm_close_driver(fd);
>>> +        free(drpc);
>>>       }
>>>       igt_subtest("module-unload") {