[intel-gem] Pin objects during execbuffer

Pinning the objects avoids accidentally evicting them while binding
other objects.

diff --git a/linux-core/i915_gem.c b/linux-core/i915_gem.c
index c2d1fab..d14b2f2 100644 (file)
--- a/linux-core/i915_gem.c
+++ b/linux-core/i915_gem.c
@@ -1298,27 +1298,25 @@ i915_gem_object_check_coherency(struct drm_gem_object *obj, int handle)
 #endif
 
 /**
- * Bind an object to the GTT and evaluate the relocations landing in it.
+ * Pin an object to the GTT and evaluate the relocations landing in it.
  */
 static int
-i915_gem_object_bind_and_relocate(struct drm_gem_object *obj,
-                                 struct drm_file *file_priv,
-                                 struct drm_i915_gem_exec_object *entry)
+i915_gem_object_pin_and_relocate(struct drm_gem_object *obj,
+                                struct drm_file *file_priv,
+                                struct drm_i915_gem_exec_object *entry)
 {
        struct drm_device *dev = obj->dev;
        struct drm_i915_gem_relocation_entry reloc;
        struct drm_i915_gem_relocation_entry __user *relocs;
        struct drm_i915_gem_object *obj_priv = obj->driver_private;
-       int i;
+       int i, ret;
        uint32_t last_reloc_offset = -1;
        void *reloc_page = NULL;
 
        /* Choose the GTT offset for our buffer and put it there. */
-       if (obj_priv->gtt_space == NULL) {
-               i915_gem_object_bind_to_gtt(obj, (unsigned) entry->alignment);
-               if (obj_priv->gtt_space == NULL)
-                       return -ENOMEM;
-       }
+       ret = i915_gem_object_pin(obj, (uint32_t) entry->alignment);
+       if (ret)
+               return ret;
 
        entry->offset = obj_priv->gtt_offset;
 
@@ -1334,13 +1332,17 @@ i915_gem_object_bind_and_relocate(struct drm_gem_object *obj,
                int ret;
 
                ret = copy_from_user(&reloc, relocs + i, sizeof(reloc));
-               if (ret != 0)
+               if (ret != 0) {
+                       i915_gem_object_unpin(obj);
                        return ret;
+               }
 
                target_obj = drm_gem_object_lookup(obj->dev, file_priv,
                                                   reloc.target_handle);
-               if (target_obj == NULL)
+               if (target_obj == NULL) {
+                       i915_gem_object_unpin(obj);
                        return -EINVAL;
+               }
                target_obj_priv = target_obj->driver_private;
 
                /* The target buffer should have appeared before us in the
@@ -1350,6 +1352,7 @@ i915_gem_object_bind_and_relocate(struct drm_gem_object *obj,
                        DRM_ERROR("No GTT space found for object %d\n",
                                  reloc.target_handle);
                        drm_gem_object_unreference(target_obj);
+                       i915_gem_object_unpin(obj);
                        return -EINVAL;
                }
 
@@ -1359,6 +1362,7 @@ i915_gem_object_bind_and_relocate(struct drm_gem_object *obj,
                                  obj, reloc.target_handle,
                                  (int) reloc.offset, (int) obj->size);
                        drm_gem_object_unreference(target_obj);
+                       i915_gem_object_unpin(obj);
                        return -EINVAL;
                }
                if (reloc.offset & 3) {
@@ -1367,6 +1371,7 @@ i915_gem_object_bind_and_relocate(struct drm_gem_object *obj,
                                  obj, reloc.target_handle,
                                  (int) reloc.offset);
                        drm_gem_object_unreference(target_obj);
+                       i915_gem_object_unpin(obj);
                        return -EINVAL;
                }
 
@@ -1380,6 +1385,7 @@ i915_gem_object_bind_and_relocate(struct drm_gem_object *obj,
                                  reloc.write_domain,
                                  target_obj->pending_write_domain);
                        drm_gem_object_unreference(target_obj);
+                       i915_gem_object_unpin(obj);
                        return -EINVAL;
                }
 
@@ -1440,6 +1446,7 @@ i915_gem_object_bind_and_relocate(struct drm_gem_object *obj,
                        last_reloc_offset = reloc_offset;
                        if (reloc_page == NULL) {
                                drm_gem_object_unreference(target_obj);
+                               i915_gem_object_unpin(obj);
                                return -ENOMEM;
                        }
                }
@@ -1462,6 +1469,7 @@ i915_gem_object_bind_and_relocate(struct drm_gem_object *obj,
                ret = copy_to_user(relocs + i, &reloc, sizeof(reloc));
                if (ret != 0) {
                        drm_gem_object_unreference(target_obj);
+                       i915_gem_object_unpin(obj);
                        return ret;
                }
 
@@ -1573,7 +1581,7 @@ i915_gem_execbuffer(struct drm_device *dev, void *data,
        struct drm_i915_gem_exec_object *exec_list = NULL;
        struct drm_gem_object **object_list = NULL;
        struct drm_gem_object *batch_obj;
-       int ret, i;
+       int ret, i, pinned = 0;
        uint64_t exec_offset;
        uint32_t seqno, flush_domains;
 
@@ -1632,13 +1640,14 @@ i915_gem_execbuffer(struct drm_device *dev, void *data,
 
                object_list[i]->pending_read_domains = 0;
                object_list[i]->pending_write_domain = 0;
-               ret = i915_gem_object_bind_and_relocate(object_list[i],
-                                                       file_priv,
-                                                       &exec_list[i]);
+               ret = i915_gem_object_pin_and_relocate(object_list[i],
+                                                      file_priv,
+                                                      &exec_list[i]);
                if (ret) {
                        DRM_ERROR("object bind and relocate failed %d\n", ret);
                        goto err;
                }
+               pinned = i;
        }
 
        /* Set the pending read domains for the batch buffer to COMMAND */
@@ -1735,6 +1744,8 @@ i915_gem_execbuffer(struct drm_device *dev, void *data,
                           args->buffer_count, ret);
 err:
        if (object_list != NULL) {
+               for (i = 0; i < pinned; i++)
+                       i915_gem_object_unpin (object_list[i]);
                for (i = 0; i < args->buffer_count; i++)
                        drm_gem_object_unreference(object_list[i]);
        }
@@ -1752,32 +1763,47 @@ pre_mutex_err:
 int
 i915_gem_object_pin(struct drm_gem_object *obj, uint32_t alignment)
 {
-       struct drm_device *dev = obj->dev;
        struct drm_i915_gem_object *obj_priv = obj->driver_private;
        int ret;
 
        if (obj_priv->gtt_space == NULL) {
                ret = i915_gem_object_bind_to_gtt(obj, alignment);
                if (ret != 0) {
-                       DRM_ERROR("Failure to bind in "
-                                 "i915_gem_pin_ioctl(): %d\n",
-                                 ret);
-                       drm_gem_object_unreference(obj);
-                       mutex_unlock(&dev->struct_mutex);
+                       DRM_ERROR("Failure to bind: %d", ret);
                        return ret;
                }
        }
-
        obj_priv->pin_count++;
+
+       /* If the object is not active and not pending a flush,
+        * remove it from the inactive list
+        */
+       if (obj_priv->pin_count == 1 &&
+           !obj_priv->active &&
+           obj->write_domain == 0)
+               list_del_init(&obj_priv->list);
+
        return 0;
 }
 
 void
 i915_gem_object_unpin(struct drm_gem_object *obj)
 {
+       struct drm_device *dev = obj->dev;
+       drm_i915_private_t *dev_priv = dev->dev_private;
        struct drm_i915_gem_object *obj_priv = obj->driver_private;
 
        obj_priv->pin_count--;
+       BUG_ON(obj_priv->pin_count < 0);
+       BUG_ON(obj_priv->gtt_space == NULL);
+       
+       /* If the object is no longer pinned, and is
+        * neither active nor being flushed, then stick it on
+        * the inactive list
+        */
+       if (obj_priv->pin_count == 0 && 
+           !obj_priv->active && obj->write_domain == 0)
+               list_move_tail(&obj_priv->list, &dev_priv->mm.inactive_list);
 }
 
 int
@@ -1963,8 +1989,10 @@ i915_gem_init_ringbuffer(struct drm_device *dev)
        obj_priv = obj->driver_private;
 
        ret = i915_gem_object_pin(obj, 4096);
-       if (ret != 0)
+       if (ret != 0) {
+               drm_gem_object_unreference(obj);
                return ret;
+       }
 
        /* Set up the kernel mapping for the ring. */
        dev_priv->ring.Size = obj->size;