[igt-dev] [PATCH i-g-t 14/16] i915/gem_exec_balancer: Exercise bonded pairs

[Chris Wilson]

Quoting Chris Wilson (2019-05-15 20:57:18)
> Quoting Tvrtko Ursulin (2019-05-15 11:58:20)
> > 
> > On 08/05/2019 11:09, Chris Wilson wrote:
> > > +                     igt_assert_f(load > 0.90,
> > > +                                  "engine %d (class:instance %d:%d) was found to be only %.1f%% busy\n",
> > > +                                  n, siblings[n].engine_class, siblings[n].engine_instance,
> > > +                                  load*100);
> > 
> > Master also needs to be checked I think. You have the infrastructure to 
> > open two pmus in the previous patch so should be easy.
> 
> Haven't we checked precisely that in earlier tests? What would perhaps
> be fairer here would be to verify the other engine was idle, otherwise
> we could say we fluked it. Furthermore, we should repeat a few times
> with say (0, 1), (0, 1), (1, 0), (1, 0) to further rule out flukes, and
> then to finish with a random smoketest of some description.
> 
> Perhaps even a test is closer to the typical workload would involve
> semaphore communication across the bond. But I don't know a way in which
> I can determine which engine I am on in order to record that from the
> GPU itself.

To remind myself, the importance here is on uABI stressing, it's is much
easier to prove the relationship in the kernel and that is where we do.
-Chris