[Intel-gfx] [PATCH v2 1/5] drm/i915: Only disable execlist preemption for the duration of the request

[Chris Wilson]

On Mon, Jan 23, 2017 at 02:33:20PM +0200, Mika Kuoppala wrote:
> Chris Wilson <chris at chris-wilson.co.uk> writes:
> 
> > On Mon, Jan 23, 2017 at 12:14:25PM +0000, Chris Wilson wrote:
> >> @@ -558,7 +558,8 @@ static bool execlists_elsp_ready(struct intel_engine_cs *engine)
> >>  	int port;
> >>  
> >>  	port = 1; /* wait for a free slot */
> >> -	if (engine->disable_lite_restore_wa || engine->preempt_wa)
> >> +	if (engine->disable_lite_restore_wa ||
> >> +	    engine->execlist_port[0].count > 1)
> >>  		port = 0; /* wait for GPU to be idle before continuing */
> >
> > The disable_lite_restore_wa is a preproduction wa, right? Do we still
> > want to keep it?
> >
> 
> I was about to suggest to getting rid of it. I remeber doing it
> but patches are lost somewhere.
> 
> The concern with the preempt_wa change is that does it work? =)

engine->preempt_wa is equivalent to engine->execlist_port[0].count == 2
so that identity is preserved here.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre