drm/i915: Search harder for a reusable object

As evict_something() is called by routines that do not repeatedly search
again, try harder in the initial search to find an object that matches
the request.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index d49ac1c..874cce6 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2113,7 +2113,6 @@ i915_gem_evict_something(struct drm_device *dev, int min_size)
 {
        drm_i915_private_t *dev_priv = dev->dev_private;
        struct drm_gem_object *obj;
-       int have_waited = 0;
        int ret;
 
        for (;;) {
@@ -2137,9 +2136,6 @@ i915_gem_evict_something(struct drm_device *dev, int min_size)
                        return i915_gem_object_unbind(obj);
                }
 
-               if (have_waited)
-                       return 0;
-
                /* If we didn't get anything, but the ring is still processing
                 * things, wait for the next to finish and hopefully leave us
                 * a buffer to evict.
@@ -2155,7 +2151,6 @@ i915_gem_evict_something(struct drm_device *dev, int min_size)
                        if (ret)
                                return ret;
 
-                       have_waited = 1;
                        continue;
                }
 
@@ -2166,26 +2161,32 @@ i915_gem_evict_something(struct drm_device *dev, int min_size)
                 */
                if (!list_empty(&dev_priv->mm.flushing_list)) {
                        struct drm_i915_gem_object *obj_priv;
-                       uint32_t seqno;
 
-                       obj_priv = list_first_entry(&dev_priv->mm.flushing_list,
-                                                   struct drm_i915_gem_object,
-                                                   list);
-                       obj = obj_priv->obj;
+                       /* Find an object that we can immediately reuse */
+                       list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, list) {
+                               obj = obj_priv->obj;
+                               if (obj->size >= min_size)
+                                       break;
 
-                       i915_gem_flush(dev,
-                                      obj->write_domain,
-                                      obj->write_domain);
-                       seqno = i915_add_request(dev, NULL, obj->write_domain);
-                       if (seqno == 0)
-                               return -ENOMEM;
+                               obj = NULL;
+                       }
 
-                       ret = i915_wait_request(dev, seqno);
-                       if (ret)
-                               return ret;
+                       if (obj != NULL) {
+                               uint32_t seqno;
 
-                       have_waited = 1;
-                       continue;
+                               i915_gem_flush(dev,
+                                              obj->write_domain,
+                                              obj->write_domain);
+                               seqno = i915_add_request(dev, NULL, obj->write_domain);
+                               if (seqno == 0)
+                                       return -ENOMEM;
+
+                               ret = i915_wait_request(dev, seqno);
+                               if (ret)
+                                       return ret;
+
+                               continue;
+                       }
                }
 
                /* If we didn't do any of the above, there's no single buffer