[Intel-gfx] [PATCH 2/2] drm/i915/selftests: exercise cache domain eviction

[Chris Wilson]

On Fri, Mar 03, 2017 at 06:03:35PM +0000, Matthew Auld wrote:
> Signed-off-by: Matthew Auld <matthew.auld at intel.com>
> ---
>  drivers/gpu/drm/i915/selftests/i915_gem_evict.c | 80 +++++++++++++++++++++++++
>  1 file changed, 80 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> index 97af353db218..e92c235d0200 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> +++ b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> @@ -202,6 +202,85 @@ static int igt_evict_for_vma(void *arg)
>  	return err;
>  }
>  
> +static void mock_color_adjust(const struct drm_mm_node *node,
> +			      unsigned long color,
> +			      u64 *start,
> +			      u64 *end)
> +{

Ah. I see, this is because evict_for_node makes the assumption that any
color_adjust is i915_ggtt_color_adjust. I was wondering. Please add a
note here about the magic.

> +}
> +
> +static int igt_evict_for_cache_color(void *arg)
> +{
> +	struct drm_i915_private *i915 = arg;
> +	struct i915_ggtt *ggtt = &i915->ggtt;
> +	const unsigned long flags = PIN_OFFSET_FIXED;
> +	struct drm_mm_node target = {
> +		.start = I915_GTT_PAGE_SIZE * 2,
> +		.size = I915_GTT_PAGE_SIZE,
> +		.color = I915_CACHE_LLC,
> +	};
> +	struct drm_i915_gem_object *obj;
> +	struct i915_vma *vma;
> +	int err;
> +
> +	ggtt->base.mm.color_adjust = mock_color_adjust;
> +
> +	obj = i915_gem_object_create_internal(i915, I915_GTT_PAGE_SIZE);
> +	if (IS_ERR(obj)) {
> +		err = PTR_ERR(obj);
> +		goto cleanup;
> +	}
> +	i915_gem_object_set_cache_level(obj, I915_CACHE_LLC);
> +
> +	vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
> +				       I915_GTT_PAGE_SIZE | flags);
> +	if (IS_ERR(vma)) {
> +		pr_err("[0]i915_gem_object_ggtt_pin failed\n");
> +		err = PTR_ERR(vma);
> +		goto cleanup;
> +	}
> +
> +	obj = i915_gem_object_create_internal(i915, I915_GTT_PAGE_SIZE);
> +	if (IS_ERR(obj)) {
> +		err = PTR_ERR(obj);
> +		goto cleanup;
> +	}
> +	i915_gem_object_set_cache_level(obj, I915_CACHE_LLC);
> +

/* Neighbouring; same colour - should fit */
> +	vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
> +				       (I915_GTT_PAGE_SIZE * 2) | flags);
> +	if (IS_ERR(vma)) {
> +		pr_err("[1]i915_gem_object_ggtt_pin failed\n");
> +		err = PTR_ERR(vma);
> +		goto cleanup;
> +	}
> +
> +	i915_vma_unpin(vma);
> +

/* Remove just the second vma */
> +	err = i915_gem_evict_for_node(&ggtt->base, &target, 0);
> +	if (err) {
> +		pr_err("[0]i915_gem_evict_for_node returned err=%d\n", err);
> +		goto cleanup;
> +	}
> +

/* Attempt to remove the first *pinned* vma, by removing the (empty) neighbour */
> +	target.color = I915_CACHE_L3_LLC;
> +
> +	err = i915_gem_evict_for_node(&ggtt->base, &target, 0);
> +	if (!err) {
> +		pr_err("[1]i915_gem_evict_for_node returned err=%d\n", err);
> +		err = -EINVAL;
> +		goto cleanup;

Your pr_err("[]") are as bad as mine ;)

I see what you're testing, looks ok. So just a couple of comments for
the next reader.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre