[Intel-gfx] [PATCH 1/2] drm/i915/guc: Fill preempt context once at init time

[Chris Wilson]

Quoting Chris Wilson (2018-02-26 14:28:36)
> Quoting Michał Winiarski (2018-02-26 13:59:59)
> > +       for_each_engine(engine, dev_priv, id) {
>                 struct intel_engine *ce = &client->owner->engine[id];
> 
>                 /* The preempt context must be pinned on each engine);
>                 GEM_BUG_ON(!ce->pin_count);
> 
>                 /*
>                  * We rely on the context image *not* being saved after
>                  * preemption. This ensures that the RING_HEAD / RING_TAIL
>                  * do not advance and they remain pointing at this command
>                  * sequence forever.
>                  */

Hmm, this is not true. See intel_lr_context_resume().

Does this patch justify a test case for gem_exec_schedule+suspend
specifically? Or do we just repeat every test after a S&R cycle? I think
we could do with the latter!
-Chris