[Intel-gfx] [PATCH 05/14] drm/i915: Handle log buffer flush interrupt event from GuC

[Chris Wilson]

On Sun, Jul 03, 2016 at 12:21:22AM +0530, akash.goel at intel.com wrote:
> +static void guc_read_update_log_buffer(struct drm_device *dev, bool capture_all)
> +{
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	struct intel_guc *guc = &dev_priv->guc;
> +	struct guc_log_buffer_state *log_buffer_state;
> +	struct guc_log_buffer_state *log_buffer_copy_state;
> +	void *src_ptr, *dst_ptr;
> +	u32 num_pages_to_copy;
> +	int i;
> +
> +	if (!guc->log.obj)
> +		return;
> +
> +	num_pages_to_copy = guc->log.obj->base.size / PAGE_SIZE;
> +	/* Don't really need to copy crash buffer area in regular cases as there
> +	 * won't be any unread data there.
> +	 */
> +	if (!capture_all)
> +		num_pages_to_copy -= (GUC_LOG_CRASH_PAGES + 1);
> +
> +	log_buffer_state = src_ptr =
> +		kmap_atomic(i915_gem_object_get_page(guc->log.obj, 0));

So why not use i915_gem_object_pin_map() from the start?

That will cut down on the churn later.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre