drm/i915: Wait for completion of pending flips when starved of fences

[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / gpu / drm / i915 / i915_gem.c

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 51d4c1a..00c8361 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2388,16 +2388,6 @@ static void i915_gem_reset_ring_status(struct drm_i915_private *dev_priv,
 static void i915_gem_reset_ring_cleanup(struct drm_i915_private *dev_priv,
                                        struct intel_ring_buffer *ring)
 {
-       while (!list_empty(&ring->request_list)) {
-               struct drm_i915_gem_request *request;
-
-               request = list_first_entry(&ring->request_list,
-                                          struct drm_i915_gem_request,
-                                          list);
-
-               i915_gem_free_request(request);
-       }
-
        while (!list_empty(&ring->active_list)) {
                struct drm_i915_gem_object *obj;
 
@@ -2407,6 +2397,23 @@ static void i915_gem_reset_ring_cleanup(struct drm_i915_private *dev_priv,
 
                i915_gem_object_move_to_inactive(obj);
        }
+
+       /*
+        * We must free the requests after all the corresponding objects have
+        * been moved off active lists. Which is the same order as the normal
+        * retire_requests function does. This is important if object hold
+        * implicit references on things like e.g. ppgtt address spaces through
+        * the request.
+        */
+       while (!list_empty(&ring->request_list)) {
+               struct drm_i915_gem_request *request;
+
+               request = list_first_entry(&ring->request_list,
+                                          struct drm_i915_gem_request,
+                                          list);
+
+               i915_gem_free_request(request);
+       }
 }
 
 void i915_gem_restore_fences(struct drm_device *dev)
@@ -3099,7 +3106,7 @@ i915_find_fence_reg(struct drm_device *dev)
        }
 
        if (avail == NULL)
-               return NULL;
+               goto deadlock;
 
        /* None available, try to steal one or wait for a user to finish */
        list_for_each_entry(reg, &dev_priv->mm.fence_list, lru_list) {
@@ -3109,7 +3116,12 @@ i915_find_fence_reg(struct drm_device *dev)
                return reg;
        }
 
-       return NULL;
+deadlock:
+       /* Wait for completion of pending flips which consume fences */
+       if (intel_has_pending_fb_unpin(dev))
+               return ERR_PTR(-EAGAIN);
+
+       return ERR_PTR(-EDEADLK);
 }
 
 /**
@@ -3154,8 +3166,8 @@ i915_gem_object_get_fence(struct drm_i915_gem_object *obj)
                }
        } else if (enable) {
                reg = i915_find_fence_reg(dev);
-               if (reg == NULL)
-                       return -EDEADLK;
+               if (IS_ERR(reg))
+                       return PTR_ERR(reg);
 
                if (reg->obj) {
                        struct drm_i915_gem_object *old = reg->obj;