[PATCH v3] drm/i915/selftests: Implement frequency check for energy reading validation

[Gupta, Anshuman]

> -----Original Message-----
> From: Pottumuttu, Sai Teja <sai.teja.pottumuttu at intel.com>
> Sent: Thursday, September 19, 2024 2:39 PM
> To: Anirban, Sk <sk.anirban at intel.com>; intel-gfx at lists.freedesktop.org; Gupta,
> Anshuman <anshuman.gupta at intel.com>
> Cc: Poosa, Karthik <karthik.poosa at intel.com>; Pottumuttu, Sai Teja
> <sai.teja.pottumuttu at intel.com>
> Subject: Re: [PATCH v3] drm/i915/selftests: Implement frequency check for
> energy reading validation
> 
> 
> On 19-09-2024 13:53, Sk Anirban wrote:
> > This commit introduces a frequency check mechanism aimed at ensuring
> > the accuracy of energy readings.
> >
> > v2:
> >    - Improved commit message.
> > v3:
> >    - Used pr_err log to display frequency. (Anshuman)
> >    - Sorted headers alphabetically. (Sai Teja)
> >
> > Signed-off-by: Sk Anirban <sk.anirban at intel.com>
> > ---
> >   drivers/gpu/drm/i915/gt/selftest_rc6.c | 8 +++++++-
> >   1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/gt/selftest_rc6.c
> > b/drivers/gpu/drm/i915/gt/selftest_rc6.c
> > index 1aa1446c8fb0..8fd6be7b826e 100644
> > --- a/drivers/gpu/drm/i915/gt/selftest_rc6.c
> > +++ b/drivers/gpu/drm/i915/gt/selftest_rc6.c
> > @@ -8,6 +8,7 @@
> >   #include "intel_gpu_commands.h"
> >   #include "intel_gt_requests.h"
> >   #include "intel_ring.h"
> > +#include "intel_rps.h"
> >   #include "selftest_rc6.h"
> >
> >   #include "selftests/i915_random.h"
> > @@ -38,6 +39,8 @@ int live_rc6_manual(void *arg)
> >   	ktime_t dt;
> >   	u64 res[2];
> >   	int err = 0;
> > +	u32 rc0_freq, rc6_freq;
> > +	struct intel_rps *rps = &gt->rps;
> >
> >   	/*
> >   	 * Our claim is that we can "encourage" the GPU to enter rc6 at will.
> > @@ -66,6 +69,7 @@ int live_rc6_manual(void *arg)
> >   	rc0_power = librapl_energy_uJ() - rc0_power;
> >   	dt = ktime_sub(ktime_get(), dt);
> >   	res[1] = rc6_residency(rc6);
> > +	rc0_freq = intel_rps_read_actual_frequency(rps);
> >   	if ((res[1] - res[0]) >> 10) {
> >   		pr_err("RC6 residency increased by %lldus while disabled for
> 1000ms!\n",
> >   		       (res[1] - res[0]) >> 10);
> > @@ -91,6 +95,7 @@ int live_rc6_manual(void *arg)
> >   	dt = ktime_get();
> >   	rc6_power = librapl_energy_uJ();
> >   	msleep(100);
> > +	rc6_freq = intel_rps_read_actual_frequency(rps);
> >   	rc6_power = librapl_energy_uJ() - rc6_power;
> >   	dt = ktime_sub(ktime_get(), dt);
> >   	res[1] = rc6_residency(rc6);
> > @@ -108,7 +113,8 @@ int live_rc6_manual(void *arg)
> >   		pr_info("GPU consumed %llduW in RC0 and %llduW in RC6\n",
> >   			rc0_power, rc6_power);
> >   		if (2 * rc6_power > rc0_power) {
> > -			pr_err("GPU leaked energy while in RC6!\n");
> > +			pr_err("GPU leaked energy while in RC6!\nGPU Freq:
> %u in RC6 and
> > +%u in RC0\n",
> 
> Probably we could have the complete log in a single line without having \n in
> between? We usually never split logs like this as far as I know.
> 
> But other than that, looks good.
@Anirban, Sk Please address above comment form Sai.

> 
> Reviewed-by: Sai Teja Pottumuttu <sai.teja.pottumuttu at intel.com>
> 
> > +			       rc6_freq, rc0_freq);
> >   			err = -EINVAL;
> >   			goto out_unlock;
> >   		}