drm/i915: Track objects in global active list (as well as per-ring)

To handle retirements, we need per-ring tracking of active objects.
To handle evictions, we need global tracking of active objects.

As we enable more rings, rebuilding the global list from the individual
per-ring lists quickly grows tiresome and overly complicated. Tracking the
active objects in two lists is the lesser of two evils.

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

drivers/gpu/drm/i915/i915_debugfs.c

@@ -41,8 +41,7 @@
 #if defined(CONFIG_DEBUG_FS)
 
 enum {
-	RENDER_LIST,
-	BSD_LIST,
+	ACTIVE_LIST,
 	FLUSHING_LIST,
 	INACTIVE_LIST,
 	PINNED_LIST,
@@ -125,6 +124,8 @@ describe_obj(struct seq_file *m, struct drm_i915_gem_object *obj)
 		seq_printf(m, " (fence: %d)", obj->fence_reg);
 	if (obj->gtt_space != NULL)
 		seq_printf(m, " (gtt_offset: %08x)", obj->gtt_offset);
+	if (obj->ring != NULL)
+		seq_printf(m, " (%s)", obj->ring->name);
 }
 
 static int i915_gem_object_list_info(struct seq_file *m, void *data)
@@ -143,13 +144,9 @@ static int i915_gem_object_list_info(struct seq_file *m, void *data)
 		return ret;
 
 	switch (list) {
-	case RENDER_LIST:
-		seq_printf(m, "Render:\n");
-		head = &dev_priv->render_ring.active_list;
-		break;
-	case BSD_LIST:
-		seq_printf(m, "BSD:\n");
-		head = &dev_priv->bsd_ring.active_list;
+	case ACTIVE_LIST:
+		seq_printf(m, "Active:\n");
+		head = &dev_priv->mm.active_list;
 		break;
 	case INACTIVE_LIST:
 		seq_printf(m, "Inactive:\n");
@@ -173,7 +170,7 @@ static int i915_gem_object_list_info(struct seq_file *m, void *data)
 	}
 
 	total_obj_size = total_gtt_size = count = 0;
-	list_for_each_entry(obj_priv, head, list) {
+	list_for_each_entry(obj_priv, head, mm_list) {
 		seq_printf(m, "   ");
 		describe_obj(m, obj_priv);
 		seq_printf(m, "\n");
@@ -460,8 +457,7 @@ static int i915_batchbuffer_info(struct seq_file *m, void *data)
 	if (ret)
 		return ret;
 
-	list_for_each_entry(obj_priv, &dev_priv->render_ring.active_list,
-			list) {
+	list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
 		obj = &obj_priv->base;
 		if (obj->read_domains & I915_GEM_DOMAIN_COMMAND) {
 		    seq_printf(m, "--- gtt_offset = 0x%08x\n",
@@ -1020,8 +1016,7 @@ static int i915_wedged_create(struct dentry *root, struct drm_minor *minor)
 static struct drm_info_list i915_debugfs_list[] = {
 	{"i915_capabilities", i915_capabilities, 0, 0},
 	{"i915_gem_objects", i915_gem_object_info, 0},
-	{"i915_gem_render_active", i915_gem_object_list_info, 0, (void *) RENDER_LIST},
-	{"i915_gem_bsd_active", i915_gem_object_list_info, 0, (void *) BSD_LIST},
+	{"i915_gem_active", i915_gem_object_list_info, 0, (void *) ACTIVE_LIST},
 	{"i915_gem_flushing", i915_gem_object_list_info, 0, (void *) FLUSHING_LIST},
 	{"i915_gem_inactive", i915_gem_object_list_info, 0, (void *) INACTIVE_LIST},
 	{"i915_gem_pinned", i915_gem_object_list_info, 0, (void *) PINNED_LIST},

drivers/gpu/drm/i915/i915_drv.h

@@ -547,6 +547,17 @@ typedef struct drm_i915_private {
 		 */
 		struct list_head shrink_list;
 
+		/**
+		 * List of objects currently involved in rendering.
+		 *
+		 * Includes buffers having the contents of their GPU caches
+		 * flushed, not necessarily primitives.  last_rendering_seqno
+		 * represents when the rendering involved will be completed.
+		 *
+		 * A reference is held on the buffer while on this list.
+		 */
+		struct list_head active_list;
+
 		/**
 		 * List of objects which are not in the ringbuffer but which
 		 * still have a write_domain which needs to be flushed before
@@ -714,7 +725,8 @@ struct drm_i915_gem_object {
 	struct drm_mm_node *gtt_space;
 
 	/** This object's place on the active/flushing/inactive lists */
-	struct list_head list;
+	struct list_head ring_list;
+	struct list_head mm_list;
 	/** This object's place on GPU write list */
 	struct list_head gpu_write_list;
 	/** This object's place on eviction list */

drivers/gpu/drm/i915/i915_gem.c

@@ -1139,7 +1139,7 @@ i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
 
 	/* Maintain LRU order of "inactive" objects */
 	if (ret == 0 && i915_gem_object_is_inactive(obj_priv))
-		list_move_tail(&obj_priv->list, &dev_priv->mm.inactive_list);
+		list_move_tail(&obj_priv->mm_list, &dev_priv->mm.inactive_list);
 
 	drm_gem_object_unreference(obj);
 unlock:
@@ -1271,7 +1271,7 @@ int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 	}
 
 	if (i915_gem_object_is_inactive(obj_priv))
-		list_move_tail(&obj_priv->list, &dev_priv->mm.inactive_list);
+		list_move_tail(&obj_priv->mm_list, &dev_priv->mm.inactive_list);
 
 	pfn = ((dev->agp->base + obj_priv->gtt_offset) >> PAGE_SHIFT) +
 		page_offset;
@@ -1565,6 +1565,7 @@ i915_gem_object_move_to_active(struct drm_gem_object *obj,
 			       struct intel_ring_buffer *ring)
 {
 	struct drm_device *dev = obj->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
 	uint32_t seqno = i915_gem_next_request_seqno(dev, ring);
 
@@ -1578,7 +1579,8 @@ i915_gem_object_move_to_active(struct drm_gem_object *obj,
 	}
 
 	/* Move from whatever list we were on to the tail of execution. */
-	list_move_tail(&obj_priv->list, &ring->active_list);
+	list_move_tail(&obj_priv->mm_list, &dev_priv->mm.active_list);
+	list_move_tail(&obj_priv->ring_list, &ring->active_list);
 	obj_priv->last_rendering_seqno = seqno;
 }
 
@@ -1590,7 +1592,8 @@ i915_gem_object_move_to_flushing(struct drm_gem_object *obj)
 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
 
 	BUG_ON(!obj_priv->active);
-	list_move_tail(&obj_priv->list, &dev_priv->mm.flushing_list);
+	list_move_tail(&obj_priv->mm_list, &dev_priv->mm.flushing_list);
+	list_del_init(&obj_priv->ring_list);
 	obj_priv->last_rendering_seqno = 0;
 }
 
@@ -1629,9 +1632,10 @@ i915_gem_object_move_to_inactive(struct drm_gem_object *obj)
 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
 
 	if (obj_priv->pin_count != 0)
-		list_move_tail(&obj_priv->list, &dev_priv->mm.pinned_list);
+		list_move_tail(&obj_priv->mm_list, &dev_priv->mm.pinned_list);
 	else
-		list_move_tail(&obj_priv->list, &dev_priv->mm.inactive_list);
+		list_move_tail(&obj_priv->mm_list, &dev_priv->mm.inactive_list);
+	list_del_init(&obj_priv->ring_list);
 
 	BUG_ON(!list_empty(&obj_priv->gpu_write_list));
 
@@ -1780,7 +1784,7 @@ static void i915_gem_reset_ring_lists(struct drm_i915_private *dev_priv,
 
 		obj_priv = list_first_entry(&ring->active_list,
 					    struct drm_i915_gem_object,
-					    list);
+					    ring_list);
 
 		obj_priv->base.write_domain = 0;
 		list_del_init(&obj_priv->gpu_write_list);
@@ -1804,7 +1808,7 @@ void i915_gem_reset(struct drm_device *dev)
 	while (!list_empty(&dev_priv->mm.flushing_list)) {
 		obj_priv = list_first_entry(&dev_priv->mm.flushing_list,
 					    struct drm_i915_gem_object,
-					    list);
+					    mm_list);
 
 		obj_priv->base.write_domain = 0;
 		list_del_init(&obj_priv->gpu_write_list);
@@ -1816,7 +1820,7 @@ void i915_gem_reset(struct drm_device *dev)
 	 */
 	list_for_each_entry(obj_priv,
 			    &dev_priv->mm.inactive_list,
-			    list)
+			    mm_list)
 	{
 		obj_priv->base.read_domains &= ~I915_GEM_GPU_DOMAINS;
 	}
@@ -1876,7 +1880,7 @@ i915_gem_retire_requests_ring(struct drm_device *dev,
 
 		obj_priv = list_first_entry(&ring->active_list,
 					    struct drm_i915_gem_object,
-					    list);
+					    ring_list);
 
 		if (!i915_seqno_passed(seqno, obj_priv->last_rendering_seqno))
 			break;
@@ -1912,7 +1916,7 @@ i915_gem_retire_requests(struct drm_device *dev)
 	     */
 	    list_for_each_entry_safe(obj_priv, tmp,
 				     &dev_priv->mm.deferred_free_list,
-				     list)
+				     mm_list)
 		    i915_gem_free_object_tail(&obj_priv->base);
 	}
 
@@ -2145,7 +2149,7 @@ i915_gem_object_unbind(struct drm_gem_object *obj)
 	BUG_ON(obj_priv->pages_refcount);
 
 	i915_gem_info_remove_gtt(dev_priv, obj->size);
-	list_del_init(&obj_priv->list);
+	list_del_init(&obj_priv->mm_list);
 
 	drm_mm_put_block(obj_priv->gtt_space);
 	obj_priv->gtt_space = NULL;
@@ -2700,7 +2704,7 @@ i915_gem_object_bind_to_gtt(struct drm_gem_object *obj, unsigned alignment)
 	}
 
 	/* keep track of bounds object by adding it to the inactive list */
-	list_add_tail(&obj_priv->list, &dev_priv->mm.inactive_list);
+	list_add_tail(&obj_priv->mm_list, &dev_priv->mm.inactive_list);
 	i915_gem_info_add_gtt(dev_priv, obj->size);
 
 	/* Assert that the object is not currently in any GPU domain. As it
@@ -4022,7 +4026,7 @@ i915_gem_object_pin(struct drm_gem_object *obj, uint32_t alignment)
 	if (obj_priv->pin_count == 1) {
 		i915_gem_info_add_pin(dev_priv, obj->size);
 		if (!obj_priv->active)
-			list_move_tail(&obj_priv->list,
+			list_move_tail(&obj_priv->mm_list,
 				       &dev_priv->mm.pinned_list);
 	}
 
@@ -4048,7 +4052,7 @@ i915_gem_object_unpin(struct drm_gem_object *obj)
 	 */
 	if (obj_priv->pin_count == 0) {
 		if (!obj_priv->active)
-			list_move_tail(&obj_priv->list,
+			list_move_tail(&obj_priv->mm_list,
 				       &dev_priv->mm.inactive_list);
 		i915_gem_info_remove_pin(dev_priv, obj->size);
 	}
@@ -4280,7 +4284,8 @@ struct drm_gem_object * i915_gem_alloc_object(struct drm_device *dev,
 	obj->agp_type = AGP_USER_MEMORY;
 	obj->base.driver_private = NULL;
 	obj->fence_reg = I915_FENCE_REG_NONE;
-	INIT_LIST_HEAD(&obj->list);
+	INIT_LIST_HEAD(&obj->mm_list);
+	INIT_LIST_HEAD(&obj->ring_list);
 	INIT_LIST_HEAD(&obj->gpu_write_list);
 	obj->madv = I915_MADV_WILLNEED;
 
@@ -4303,7 +4308,7 @@ static void i915_gem_free_object_tail(struct drm_gem_object *obj)
 
 	ret = i915_gem_object_unbind(obj);
 	if (ret == -ERESTARTSYS) {
-		list_move(&obj_priv->list,
+		list_move(&obj_priv->mm_list,
 			  &dev_priv->mm.deferred_free_list);
 		return;
 	}
@@ -4511,6 +4516,7 @@ i915_gem_entervt_ioctl(struct drm_device *dev, void *data,
 		return ret;
 	}
 
+	BUG_ON(!list_empty(&dev_priv->mm.active_list));
 	BUG_ON(!list_empty(&dev_priv->render_ring.active_list));
 	BUG_ON(!list_empty(&dev_priv->bsd_ring.active_list));
 	BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
@@ -4564,6 +4570,7 @@ i915_gem_load(struct drm_device *dev)
 	int i;
 	drm_i915_private_t *dev_priv = dev->dev_private;
 
+	INIT_LIST_HEAD(&dev_priv->mm.active_list);
 	INIT_LIST_HEAD(&dev_priv->mm.flushing_list);
 	INIT_LIST_HEAD(&dev_priv->mm.gpu_write_list);
 	INIT_LIST_HEAD(&dev_priv->mm.inactive_list);
@@ -4859,7 +4866,7 @@ i915_gem_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
 			if (mutex_trylock(&dev->struct_mutex)) {
 				list_for_each_entry(obj_priv,
 						    &dev_priv->mm.inactive_list,
-						    list)
+						    mm_list)
 					cnt++;
 				mutex_unlock(&dev->struct_mutex);
 			}
@@ -4885,7 +4892,7 @@ rescan:
 
 		list_for_each_entry_safe(obj_priv, next_obj,
 					 &dev_priv->mm.inactive_list,
-					 list) {
+					 mm_list) {
 			if (i915_gem_object_is_purgeable(obj_priv)) {
 				i915_gem_object_unbind(&obj_priv->base);
 				if (--nr_to_scan <= 0)
@@ -4914,7 +4921,7 @@ rescan:
 
 		list_for_each_entry_safe(obj_priv, next_obj,
 					 &dev_priv->mm.inactive_list,
-					 list) {
+					 mm_list) {
 			if (nr_to_scan > 0) {
 				i915_gem_object_unbind(&obj_priv->base);
 				nr_to_scan--;

drivers/gpu/drm/i915/i915_gem_evict.c

@@ -31,49 +31,6 @@
 #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)
@@ -83,18 +40,12 @@ mark_free(struct drm_i915_gem_object *obj_priv,
 	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;
-	struct list_head *render_iter, *bsd_iter;
 	int ret = 0;
 
 	i915_gem_retire_requests(dev);
@@ -131,13 +82,13 @@ i915_gem_evict_something(struct drm_device *dev, int min_size, unsigned alignmen
 	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) {
+	list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, mm_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) {
+	list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
 		/* Does the object require an outstanding flush? */
 		if (obj_priv->base.write_domain || obj_priv->pin_count)
 			continue;
@@ -147,14 +98,14 @@ i915_gem_evict_something(struct drm_device *dev, int min_size, unsigned alignmen
 	}
 
 	/* Finally add anything with a pending flush (in order of retirement) */
-	list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, list) {
+	list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, mm_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) {
+	list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
 		if (! obj_priv->base.write_domain || obj_priv->pin_count)
 			continue;
 
@@ -251,7 +202,7 @@ i915_gem_evict_inactive(struct drm_device *dev)
 
 		obj = &list_first_entry(&dev_priv->mm.inactive_list,
 					struct drm_i915_gem_object,
-					list)->base;
+					mm_list)->base;
 
 		ret = i915_gem_object_unbind(obj);
 		if (ret != 0) {

drivers/gpu/drm/i915/i915_irq.c

@@ -608,9 +608,7 @@ static void i915_capture_error_state(struct drm_device *dev)
 	batchbuffer[0] = NULL;
 	batchbuffer[1] = NULL;
 	count = 0;
-	list_for_each_entry(obj_priv,
-			&dev_priv->render_ring.active_list, list) {
-
+	list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
 		struct drm_gem_object *obj = &obj_priv->base;
 
 		if (batchbuffer[0] == NULL &&
@@ -627,7 +625,7 @@ static void i915_capture_error_state(struct drm_device *dev)
 	}
 	/* Scan the other lists for completeness for those bizarre errors. */
 	if (batchbuffer[0] == NULL || batchbuffer[1] == NULL) {
-		list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, list) {
+		list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, mm_list) {
 			struct drm_gem_object *obj = &obj_priv->base;
 
 			if (batchbuffer[0] == NULL &&
@@ -645,7 +643,7 @@ static void i915_capture_error_state(struct drm_device *dev)
 		}
 	}
 	if (batchbuffer[0] == NULL || batchbuffer[1] == NULL) {
-		list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, list) {
+		list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, mm_list) {
 			struct drm_gem_object *obj = &obj_priv->base;
 
 			if (batchbuffer[0] == NULL &&
@@ -686,8 +684,7 @@ static void i915_capture_error_state(struct drm_device *dev)
 
 	if (error->active_bo) {
 		int i = 0;
-		list_for_each_entry(obj_priv,
-				&dev_priv->render_ring.active_list, list) {
+		list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
 			struct drm_gem_object *obj = &obj_priv->base;
 
 			error->active_bo[i].size = obj->size;