[PATCH i-g-t] tests/intel/i915_hangman: Fix spin engine hang

[Krzysztof Karas]

Hi Mikołaj,

> +static bool
> +is_bcs_ccs(const struct intel_execution_engine2 *e) {
> +	return I915_ENGINE_CLASS_COMPUTE == e->class ||
> +		I915_ENGINE_CLASS_COPY == e->class;
I think you could swap these around: e->class ==
I915_ENGINE_CLASS_COMPUTE || e->class == I915_ENGINE_CLASS_COPY.
While logic remains the same, you'll show that you check e->class
for certain values, not other way around.

> +}
> +
>  static void
>  test_engine_hang(const intel_ctx_t *ctx,
>  		 const struct intel_execution_engine2 *e, unsigned int flags)
> @@ -388,6 +394,12 @@ test_engine_hang(const intel_ctx_t *ctx,
>  	 */
>  	num_ctx = 0;
>  	for_each_ctx_engine(device, ctx, other) {
> +		/* Wa_14014494547:DG2 */
> +		if (IS_DG2(intel_get_drm_devid(device)) &&
> +		    is_bcs_ccs(e) &&
> +		    is_bcs_ccs(other))
Does for_each_ctx_engine() "know" if e == other? If it just iterates
over all engines, then you'd also skip cases where both point to the
same engine (e == other == bcs0 and e == other == ccs0), so in result
nothing would be run in background on those.

Krzysztof

> +			continue;
> +