[Intel-gfx] [PATCH 3/3] drm/i915: rename & update eb_select_ring()

[Chris Wilson]

On Wed, Jul 20, 2016 at 06:16:07PM +0100, Dave Gordon wrote:
> 'ring' is an old deprecated term for a GPU engine, so we're trying to
> phase out all such terminology. eb_select_ring() not only has 'ring'
> (meaning engine) in its name, but it has an ugly calling convention
> whereby it returns an errno and stores a pointer-to-engine indirectly
> through an output parameter. As there is only one error it ever returns
> (-EINVAL), we can make it return the pointer directly, and have the
> caller pass back the error code -EINVAL if the pointer result is NULL.
> 
> Thus we can replace
> -	ret = eb_select_ring(dev_priv, file, args, &engine);
> -	if (ret)
> -		return ret;
> with
> +	engine = eb_select_engine(dev_priv, file, args);
> +	if (!engine)
> +		return -EINVAL;
> for increased clarity and maybe save a few cycles too.
> 
> Signed-off-by: Dave Gordon <david.s.gordon at intel.com>

Thanks. I feel foolish for missing that easy transform before.
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>

There's a bsd_ring buried beneath here as well...
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre