drm/i915: Inline i915_gem_ring_retire_request()

Change the semantics to retire any buffer older than the current seqno
rather than repeatedly calling calling the function to retire the
buffer at the head of the list matching the request seqno.

Whilst this should have no semantic impact on the implementation, Daniel
was wondering if there was a bug where we might miss a retirement and so
end up with a continually growing active list.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/i915_gem.c

@@ -1667,47 +1667,6 @@ i915_retire_commands(struct drm_device *dev, struct intel_ring_buffer *ring)
 			I915_GEM_DOMAIN_COMMAND, flush_domains);
 }
 
-/**
- * Moves buffers associated only with the given active seqno from the active
- * to inactive list, potentially freeing them.
- */
-static void
-i915_gem_retire_request(struct drm_device *dev,
-			struct drm_i915_gem_request *request)
-{
-	trace_i915_gem_request_retire(dev, request->seqno);
-
-	/* Move any buffers on the active list that are no longer referenced
-	 * by the ringbuffer to the flushing/inactive lists as appropriate.
-	 */
-	while (!list_empty(&request->ring->active_list)) {
-		struct drm_gem_object *obj;
-		struct drm_i915_gem_object *obj_priv;
-
-		obj_priv = list_first_entry(&request->ring->active_list,
-					    struct drm_i915_gem_object,
-					    list);
-		obj = &obj_priv->base;
-
-		/* If the seqno being retired doesn't match the oldest in the
-		 * list, then the oldest in the list must still be newer than
-		 * this seqno.
-		 */
-		if (obj_priv->last_rendering_seqno != request->seqno)
-			return;
-
-#if WATCH_LRU
-		DRM_INFO("%s: retire %d moves to inactive list %p\n",
-			 __func__, request->seqno, obj);
-#endif
-
-		if (obj->write_domain != 0)
-			i915_gem_object_move_to_flushing(obj);
-		else
-			i915_gem_object_move_to_inactive(obj);
-	}
-}
-
 /**
  * Returns true if seq1 is later than seq2.
  */
@@ -1733,36 +1692,62 @@ i915_gem_retire_requests_ring(struct drm_device *dev,
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;
 	uint32_t seqno;
+	bool wedged;
 
-	if (!ring->status_page.page_addr
-			|| list_empty(&ring->request_list))
+	if (!ring->status_page.page_addr ||
+	    list_empty(&ring->request_list))
 		return;
 
 	seqno = i915_get_gem_seqno(dev, ring);
+	wedged = atomic_read(&dev_priv->mm.wedged);
 
 	while (!list_empty(&ring->request_list)) {
 		struct drm_i915_gem_request *request;
-		uint32_t retiring_seqno;
 
 		request = list_first_entry(&ring->request_list,
 					   struct drm_i915_gem_request,
 					   list);
-		retiring_seqno = request->seqno;
 
-		if (i915_seqno_passed(seqno, retiring_seqno) ||
-		    atomic_read(&dev_priv->mm.wedged)) {
-			i915_gem_retire_request(dev, request);
+		if (!wedged && !i915_seqno_passed(seqno, request->seqno))
+			break;
+
+		trace_i915_gem_request_retire(dev, request->seqno);
+
+		list_del(&request->list);
+		list_del(&request->client_list);
+		kfree(request);
+	}
+
+	/* Move any buffers on the active list that are no longer referenced
+	 * by the ringbuffer to the flushing/inactive lists as appropriate.
+	 */
+	while (!list_empty(&ring->active_list)) {
+		struct drm_gem_object *obj;
+		struct drm_i915_gem_object *obj_priv;
+
+		obj_priv = list_first_entry(&ring->active_list,
+					    struct drm_i915_gem_object,
+					    list);
 
-			list_del(&request->list);
-			list_del(&request->client_list);
-			kfree(request);
-		} else
+		if (!wedged &&
+		    !i915_seqno_passed(seqno, obj_priv->last_rendering_seqno))
 			break;
+
+		obj = &obj_priv->base;
+
+#if WATCH_LRU
+		DRM_INFO("%s: retire %d moves to inactive list %p\n",
+			 __func__, request->seqno, obj);
+#endif
+
+		if (obj->write_domain != 0)
+			i915_gem_object_move_to_flushing(obj);
+		else
+			i915_gem_object_move_to_inactive(obj);
 	}
 
 	if (unlikely (dev_priv->trace_irq_seqno &&
 		      i915_seqno_passed(dev_priv->trace_irq_seqno, seqno))) {
-
 		ring->user_irq_put(dev, ring);
 		dev_priv->trace_irq_seqno = 0;
 	}