1 files changed, 271 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
new file mode 100644
index 00000000000..72cae3cccad
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_gem_evict.c
@@ -0,0 +1,271 @@
+/*
+ * Copyright © 2008-2010 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * Authors:
+ *    Eric Anholt <eric@anholt.net>
+ *    Chris Wilson <chris@chris-wilson.co.uuk>
+ *
+ */
+
+#include "drmP.h"
+#include "drm.h"
+#include "i915_drv.h"
+#include "i915_drm.h"
+
+static struct drm_i915_gem_object *
+i915_gem_next_active_object(struct drm_device *dev,
+			    struct list_head **render_iter,
+			    struct list_head **bsd_iter)
+{
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct drm_i915_gem_object *render_obj = NULL, *bsd_obj = NULL;
+
+	if (*render_iter != &dev_priv->render_ring.active_list)
+		render_obj = list_entry(*render_iter,
+					struct drm_i915_gem_object,
+					list);
+
+	if (HAS_BSD(dev)) {
+		if (*bsd_iter != &dev_priv->bsd_ring.active_list)
+			bsd_obj = list_entry(*bsd_iter,
+					     struct drm_i915_gem_object,
+					     list);
+
+		if (render_obj == NULL) {
+			*bsd_iter = (*bsd_iter)->next;
+			return bsd_obj;
+		}
+
+		if (bsd_obj == NULL) {
+			*render_iter = (*render_iter)->next;
+			return render_obj;
+		}
+
+		/* XXX can we handle seqno wrapping? */
+		if (render_obj->last_rendering_seqno < bsd_obj->last_rendering_seqno) {
+			*render_iter = (*render_iter)->next;
+			return render_obj;
+		} else {
+			*bsd_iter = (*bsd_iter)->next;
+			return bsd_obj;
+		}
+	} else {
+		*render_iter = (*render_iter)->next;
+		return render_obj;
+	}
+}
+
+static bool
+mark_free(struct drm_i915_gem_object *obj_priv,
+	   struct list_head *unwind)
+{
+	list_add(&obj_priv->evict_list, unwind);
+	return drm_mm_scan_add_block(obj_priv->gtt_space);
+}
+
+#define i915_for_each_active_object(OBJ, R, B) \
+	*(R) = dev_priv->render_ring.active_list.next; \
+	*(B) = dev_priv->bsd_ring.active_list.next; \
+	while (((OBJ) = i915_gem_next_active_object(dev, (R), (B))) != NULL)
+
+int
+i915_gem_evict_something(struct drm_device *dev, int min_size, unsigned alignment)
+{
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct list_head eviction_list, unwind_list;
+	struct drm_i915_gem_object *obj_priv, *tmp_obj_priv;
+	struct list_head *render_iter, *bsd_iter;
+	int ret = 0;
+
+	i915_gem_retire_requests(dev);
+
+	/* Re-check for free space after retiring requests */
+	if (drm_mm_search_free(&dev_priv->mm.gtt_space,
+			       min_size, alignment, 0))
+		return 0;
+
+	/*
+	 * The goal is to evict objects and amalgamate space in LRU order.
+	 * The oldest idle objects reside on the inactive list, which is in
+	 * retirement order. The next objects to retire are those on the (per
+	 * ring) active list that do not have an outstanding flush. Once the
+	 * hardware reports completion (the seqno is updated after the
+	 * batchbuffer has been finished) the clean buffer objects would
+	 * be retired to the inactive list. Any dirty objects would be added
+	 * to the tail of the flushing list. So after processing the clean
+	 * active objects we need to emit a MI_FLUSH to retire the flushing
+	 * list, hence the retirement order of the flushing list is in
+	 * advance of the dirty objects on the active lists.
+	 *
+	 * The retirement sequence is thus:
+	 *   1. Inactive objects (already retired)
+	 *   2. Clean active objects
+	 *   3. Flushing list
+	 *   4. Dirty active objects.
+	 *
+	 * On each list, the oldest objects lie at the HEAD with the freshest
+	 * object on the TAIL.
+	 */
+
+	INIT_LIST_HEAD(&unwind_list);
+	drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment);
+
+	/* First see if there is a large enough contiguous idle region... */
+	list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, list) {
+		if (mark_free(obj_priv, &unwind_list))
+			goto found;
+	}
+
+	/* Now merge in the soon-to-be-expired objects... */
+	i915_for_each_active_object(obj_priv, &render_iter, &bsd_iter) {
+		/* Does the object require an outstanding flush? */
+		if (obj_priv->base.write_domain || obj_priv->pin_count)
+			continue;
+
+		if (mark_free(obj_priv, &unwind_list))
+			goto found;
+	}
+
+	/* Finally add anything with a pending flush (in order of retirement) */
+	list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, list) {
+		if (obj_priv->pin_count)
+			continue;
+
+		if (mark_free(obj_priv, &unwind_list))
+			goto found;
+	}
+	i915_for_each_active_object(obj_priv, &render_iter, &bsd_iter) {
+		if (! obj_priv->base.write_domain || obj_priv->pin_count)
+			continue;
+
+		if (mark_free(obj_priv, &unwind_list))
+			goto found;
+	}
+
+	/* Nothing found, clean up and bail out! */
+	list_for_each_entry(obj_priv, &unwind_list, evict_list) {
+		ret = drm_mm_scan_remove_block(obj_priv->gtt_space);
+		BUG_ON(ret);
+	}
+
+	/* We expect the caller to unpin, evict all and try again, or give up.
+	 * So calling i915_gem_evict_everything() is unnecessary.
+	 */
+	return -ENOSPC;
+
+found:
+	INIT_LIST_HEAD(&eviction_list);
+	list_for_each_entry_safe(obj_priv, tmp_obj_priv,
+				 &unwind_list, evict_list) {
+		if (drm_mm_scan_remove_block(obj_priv->gtt_space)) {
+			/* drm_mm doesn't allow any other other operations while
+			 * scanning, therefore store to be evicted objects on a
+			 * temporary list. */
+			list_move(&obj_priv->evict_list, &eviction_list);
+		}
+	}
+
+	/* Unbinding will emit any required flushes */
+	list_for_each_entry_safe(obj_priv, tmp_obj_priv,
+				 &eviction_list, evict_list) {
+#if WATCH_LRU
+		DRM_INFO("%s: evicting %p\n", __func__, obj);
+#endif
+		ret = i915_gem_object_unbind(&obj_priv->base);
+		if (ret)
+			return ret;
+	}
+
+	/* The just created free hole should be on the top of the free stack
+	 * maintained by drm_mm, so this BUG_ON actually executes in O(1).
+	 * Furthermore all accessed data has just recently been used, so it
+	 * should be really fast, too. */
+	BUG_ON(!drm_mm_search_free(&dev_priv->mm.gtt_space, min_size,
+				   alignment, 0));
+
+	return 0;
+}
+
+int
+i915_gem_evict_everything(struct drm_device *dev)
+{
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	int ret;
+	bool lists_empty;
+
+	spin_lock(&dev_priv->mm.active_list_lock);
+	lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
+		       list_empty(&dev_priv->mm.flushing_list) &&
+		       list_empty(&dev_priv->render_ring.active_list) &&
+		       (!HAS_BSD(dev)
+			|| list_empty(&dev_priv->bsd_ring.active_list)));
+	spin_unlock(&dev_priv->mm.active_list_lock);
+
+	if (lists_empty)
+		return -ENOSPC;
+
+	/* Flush everything (on to the inactive lists) and evict */
+	ret = i915_gpu_idle(dev);
+	if (ret)
+		return ret;
+
+	BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
+
+	ret = i915_gem_evict_inactive(dev);
+	if (ret)
+		return ret;
+
+	spin_lock(&dev_priv->mm.active_list_lock);
+	lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
+		       list_empty(&dev_priv->mm.flushing_list) &&
+		       list_empty(&dev_priv->render_ring.active_list) &&
+		       (!HAS_BSD(dev)
+			|| list_empty(&dev_priv->bsd_ring.active_list)));
+	spin_unlock(&dev_priv->mm.active_list_lock);
+	BUG_ON(!lists_empty);
+
+	return 0;
+}
+
+/** Unbinds all inactive objects. */
+int
+i915_gem_evict_inactive(struct drm_device *dev)
+{
+	drm_i915_private_t *dev_priv = dev->dev_private;
+
+	while (!list_empty(&dev_priv->mm.inactive_list)) {
+		struct drm_gem_object *obj;
+		int ret;
+
+		obj = &list_first_entry(&dev_priv->mm.inactive_list,
+					struct drm_i915_gem_object,
+					list)->base;
+
+		ret = i915_gem_object_unbind(obj);
+		if (ret != 0) {
+			DRM_ERROR("Error unbinding object: %d\n", ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}