[Intel-gfx] [PATCH] drm/i915: Skip fence installation for objects with rotated views (v4)

[Ville Syrjälä]

On Thu, Oct 29, 2015 at 06:54:38PM -0700, Vivek Kasireddy wrote:
> While pinning a fb object to the display plane, only install a fence
> if the object is using a normal view. This corresponds with the
> behavior found in i915_gem_object_do_pin() where the fencability
> criteria is determined only for objects with normal views.
> 
> v2:
> Look at the object's map_and_fenceable flag to determine whether to
> install a fence or not (Chris).
> 
> v3:
> Pin and unpin a fence only if the current view type is normal.
> 
> v4:
> Extend the "view type is normal" check for pin_fence as well.
> 
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
> Signed-off-by: Vivek Kasireddy <vivek.kasireddy at intel.com>

lgtm
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

> ---
>  drivers/gpu/drm/i915/intel_display.c | 36 ++++++++++++++++++++----------------
>  1 file changed, 20 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 2fdfca1..9c80968 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -2419,22 +2419,24 @@ intel_pin_and_fence_fb_obj(struct drm_plane *plane,
>  	 * framebuffer compression.  For simplicity, we always install
>  	 * a fence as the cost is not that onerous.
>  	 */
> -	ret = i915_gem_object_get_fence(obj);
> -	if (ret == -EDEADLK) {
> -		/*
> -		 * -EDEADLK means there are no free fences
> -		 * no pending flips.
> -		 *
> -		 * This is propagated to atomic, but it uses
> -		 * -EDEADLK to force a locking recovery, so
> -		 * change the returned error to -EBUSY.
> -		 */
> -		ret = -EBUSY;
> -		goto err_unpin;
> -	} else if (ret)
> -		goto err_unpin;
> +	if (view.type == I915_GGTT_VIEW_NORMAL) {
> +		ret = i915_gem_object_get_fence(obj);
> +		if (ret == -EDEADLK) {
> +			/*
> +			 * -EDEADLK means there are no free fences
> +			 * no pending flips.
> +			 *
> +			 * This is propagated to atomic, but it uses
> +			 * -EDEADLK to force a locking recovery, so
> +			 * change the returned error to -EBUSY.
> +			 */
> +			ret = -EBUSY;
> +			goto err_unpin;
> +		} else if (ret)
> +			goto err_unpin;
>  
> -	i915_gem_object_pin_fence(obj);
> +		i915_gem_object_pin_fence(obj);
> +	}
>  
>  	dev_priv->mm.interruptible = true;
>  	intel_runtime_pm_put(dev_priv);
> @@ -2460,7 +2462,9 @@ static void intel_unpin_fb_obj(struct drm_framebuffer *fb,
>  	ret = intel_fill_fb_ggtt_view(&view, fb, plane_state);
>  	WARN_ONCE(ret, "Couldn't get view from plane state!");
>  
> -	i915_gem_object_unpin_fence(obj);
> +	if (view.type == I915_GGTT_VIEW_NORMAL)
> +		i915_gem_object_unpin_fence(obj);
> +
>  	i915_gem_object_unpin_from_display_plane(obj, &view);
>  }
>  
> -- 
> 2.4.3

-- 
Ville Syrjälä
Intel OTC