Re: [PATCH 2/8] drm/i915/selftests: Prevent the timeslice expiring during suppression tests

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Quoting Mika Kuoppala (2019-08-12 10:39:01)
> Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> writes:
> 
> > When testing whether we prevent suppressing preemption, it helps to
> > avoid a time slice expiring prematurely.
> >
> 
> I did look the test and it does call schedule on it's own.
> 
> So what we want to do is to postpone the defacto schedule tick
> provided by driver not to mess our own schedule? (which we
> use to check that no preemption does occur with equal
> priorities?)

The test is trying to look at our mechanics to ensure that we don't
cause preemptions where we simply put back the same request. As such, we
have a marker in the preemption code that we are trying to avoid, and
must control the scheduling to exclude all other events than the one we
are injecting.

The timeslice could expire and reverse A,B (to B,A) such that our
promotion of A does (correctly) cause a preemption that we expect never
to need.
-Chris
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [AMD Graphics]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux