Re: [PATCH v1] drm/i915/selftest: Change throttle criteria for rps

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Wed, Jan 08, 2025 at 11:28:47AM +0200, Raag Jadav wrote:
> On Thu, Jan 02, 2025 at 04:36:18PM +0530, Raag Jadav wrote:
> > Current live_rps_control() implementation errors out on throttling.
> > This was done with the assumption that throttling to minimum frequency
> > is a catastrophic failure, which is incorrect. Throttling can happen
> > due to variety of reasons and often times out of our control. Also,
> > the resulting frequency can be at any given point below the maximum
> > allowed. Change throttle criteria to reflect this logic and drop the
> > error, as it doesn't necessarily mean selftest failure.
> > 
> > Signed-off-by: Raag Jadav <raag.jadav@intel.com>
> > ---
> 
> Rodrigo, does this look okay?

Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

> 
> Raag
> 
> >  drivers/gpu/drm/i915/gt/selftest_rps.c | 11 ++++++-----
> >  1 file changed, 6 insertions(+), 5 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/gt/selftest_rps.c b/drivers/gpu/drm/i915/gt/selftest_rps.c
> > index dcef8d498919..7aac90c1679e 100644
> > --- a/drivers/gpu/drm/i915/gt/selftest_rps.c
> > +++ b/drivers/gpu/drm/i915/gt/selftest_rps.c
> > @@ -477,12 +477,13 @@ int live_rps_control(void *arg)
> >  			limit, intel_gpu_freq(rps, limit),
> >  			min, max, ktime_to_ns(min_dt), ktime_to_ns(max_dt));
> >  
> > -		if (limit == rps->min_freq) {
> > -			pr_err("%s: GPU throttled to minimum!\n",
> > -			       engine->name);
> > +		if (limit != rps->max_freq) {
> > +			u32 throttle = intel_uncore_read(gt->uncore,
> > +							 intel_gt_perf_limit_reasons_reg(gt));
> > +
> > +			pr_warn("%s: GPU throttled with reasons 0x%08x\n",
> > +				engine->name, throttle & GT0_PERF_LIMIT_REASONS_MASK);
> >  			show_pstate_limits(rps);
> > -			err = -ENODEV;
> > -			break;
> >  		}
> >  
> >  		if (igt_flush_test(gt->i915)) {
> > -- 
> > 2.34.1
> >