[Intel-gfx] [PATCH 05/15] drm/i915: Check execlist/ring status during hangcheck

[Michel Thierry]

On 17/07/17 02:11, Chris Wilson wrote:
> Before we declare an engine as idle, check if there are any pending
> execlist context-switches and if the ring itself reports as idle.
> Otherwise, we may be left in a situation where we miss a crucial
> execlist event (or something more sinister) yet the requests complete.
> Since the seqno write happens, we believe the engine to be truly idle.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/intel_hangcheck.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_hangcheck.c b/drivers/gpu/drm/i915/intel_hangcheck.c
> index 9b0ece427bdc..d9d87d96fb69 100644
> --- a/drivers/gpu/drm/i915/intel_hangcheck.c
> +++ b/drivers/gpu/drm/i915/intel_hangcheck.c
> @@ -324,7 +324,7 @@ hangcheck_get_action(struct intel_engine_cs *engine,
>   	if (engine->hangcheck.seqno != hc->seqno)
>   		return ENGINE_ACTIVE_SEQNO;
>   
> -	if (i915_seqno_passed(hc->seqno, intel_engine_last_submit(engine)))
> +	if (intel_engine_is_idle(engine))
>   		return ENGINE_IDLE;
>   
>   	return engine_stuck(engine, hc->acthd);
> 

Reviewed-by: Michel Thierry <michel.thierry at intel.com>