[Intel-gfx] drm/i915: Watchdog timeout: IRQ handler for gen8+

[Chris Wilson]

Quoting Tvrtko Ursulin (2019-01-07 13:43:29)
> 
> On 07/01/2019 11:58, Tvrtko Ursulin wrote:
> 
> [snip]
> 
> >> Note about future interaction with preemption: Preemption could happen
> >> in a command sequence prior to watchdog counter getting disabled,
> >> resulting in watchdog being triggered following preemption (e.g. when
> >> watchdog had been enabled in the low priority batch). The driver will
> >> need to explicitly disable the watchdog counter as part of the
> >> preemption sequence.
> > 
> > Does the series take care of preemption?
> 
> I did not find that it does.

Oh. I hoped that the watchdog was saved as part of the context... Then
despite preemption, the timeout would resume from where we left off as
soon as it was back on the gpu.

If the timeout remaining was context saved it would be much simpler (at
least on first glance), please say it is.
-Chris