[Intel-gfx] [PATCH v8 09/13] drm/i915: add a new perf configuration execbuf parameter

[Chris Wilson]

Quoting Lionel Landwerlin (2019-07-09 13:33:47)
> +static int eb_oa_config(struct i915_execbuffer *eb)
> +{
> +       int ret;
> +
> +       if (!eb->oa_config)
> +               return 0;
> +
> +       ret = i915_mutex_lock_interruptible(&eb->i915->drm);
> +       if (ret)
> +               return ret;
> +
> +       ret = i915_active_request_set(&eb->engine->last_oa_config,
> +                                     eb->request);

> diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
> index df5932f5f578..25ef0107d7f5 100644
> --- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
> +++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
> @@ -864,6 +864,8 @@ int intel_engine_init_common(struct intel_engine_cs *engine)
>  
>         engine->set_default_submission(engine);
>  
> +       INIT_ACTIVE_REQUEST(&engine->last_oa_config);

Fwiw, I've written the lockdep tracking patches so that you are forced
to nominate which lock guards the active-request and hopefully that will
help explain why I don't like this under engine.
-Chris