[Bf-blender-cvs] [e4edc88] soc-2013-depsgraph_mt: Update metaballs in a single thread

[Sergey Sharybin]

Commit: e4edc882ae7db81b7e2b3552411463febf0a6bcb
Author: Sergey Sharybin
Date:   Tue Dec 10 16:28:03 2013 +0600
http://developer.blender.org/rBe4edc882ae7db81b7e2b3552411463febf0a6bcb

Update metaballs in a single thread

Mballs evaluation uses BKE_scene_base_iter_next which calls
duplilist for all objects in the scene. This leads to conflict
accessing and writing same data from multiple threads.

Ideally Mballs shouldn't do such an iteration and use DAG
queries instead. For the time being we've got new DAG
let's keep it simple and update mballs in a ingle thread.

===================================================================

M	source/blender/blenkernel/intern/scene.c

===================================================================

diff --git a/source/blender/blenkernel/intern/scene.c b/source/blender/blenkernel/intern/scene.c
index 6fd9148..d188d54 100644
--- a/source/blender/blenkernel/intern/scene.c
+++ b/source/blender/blenkernel/intern/scene.c
@@ -1181,6 +1181,16 @@ static void scene_do_rb_simulation_recursive(Scene *scene, float ctime)
  */
 #undef DETAILED_ANALYSIS_OUTPUT
 
+/* Mballs evaluation uses BKE_scene_base_iter_next which calls
+ * duplilist for all objects in the scene. This leads to conflict
+ * accessing and writing same data from multiple threads.
+ *
+ * Ideally Mballs shouldn't do such an iteration and use DAG
+ * queries instead. For the time being we've got new DAG
+ * let's keep it simple and update mballs in a ingle thread.
+ */
+#define MBALL_SINGLETHREAD_HACK
+
 typedef struct StatisicsEntry {
 	struct StatisicsEntry *next, *prev;
 	Object *object;
@@ -1198,6 +1208,10 @@ typedef struct ThreadedObjectUpdateState {
 	/* Execution statistics */
 	ListBase statistics[BLENDER_MAX_THREADS];
 	bool has_updated_objects;
+
+#ifdef MBALL_SINGLETHREAD_HACK
+	bool has_mballs;
+#endif
 } ThreadedObjectUpdateState;
 
 static void scene_update_object_add_task(void *node, void *user_data);
@@ -1233,6 +1247,12 @@ static void scene_update_object_func(TaskPool *pool, void *taskdata, int threadi
 	Scene *scene = state->scene;
 	Scene *scene_parent = state->scene_parent;
 
+#ifdef MBALL_SINGLETHREAD_HACK
+	if (object && object->type == OB_MBALL) {
+		state->has_mballs = true;
+	}
+	else
+#endif
 	if (object) {
 		double start_time = 0.0;
 		bool add_to_stats = false;
@@ -1361,6 +1381,9 @@ static void scene_update_objects(EvaluationContext *evaluation_context, Scene *s
 	memset(state.statistics, 0, sizeof(state.statistics));
 	state.has_updated_objects = false;
 	state.base_time = PIL_check_seconds_timer();
+#ifdef MBALL_SINGLETHREAD_HACK
+	state.has_mballs = false;
+#endif
 
 	task_pool = BLI_task_pool_create(task_scheduler, &state);
 
@@ -1371,6 +1394,12 @@ static void scene_update_objects(EvaluationContext *evaluation_context, Scene *s
 	if (G.debug & G_DEBUG) {
 		print_threads_statistics(&state);
 	}
+
+#ifdef MBALL_SINGLETHREAD_HACK
+	if (state.has_mballs) {
+		scene_update_all_bases(evaluation_context, scene, scene_parent);
+	}
+#endif
 }
 
  static void scene_update_tagged_recursive(EvaluationContext *evaluation_context, Main *bmain, Scene *scene, Scene *scene_parent, bool use_threads)