Cleanup: BLI_task - API changes.

Based on usages so far:
- Split callback worker func in two, 'basic' and 'extended' versions. The former goes back
  to the simplest verion, while the later keeps the 'userdata_chunk', and gets the thread_id too.
- Add use_threading to simple BLI_task_parallel_range(), turns out we need this pretty much systematically,
  and allows to get rid of most usages of BLI_task_parallel_range_ex().
- Now BLI_task_parallel_range() expects 'basic' version of callback, while BLI_task_parallel_range_ex()
  expectes 'extended' version of the callback.

All in all, this should make common usage of BLI_task_parallel_range simpler (less verbose), and add
access to advanced callback to thread id, which is mandatory in some (future) cases.

11 files changed, 218 insertions, 132 deletions

diff --git a/source/blender/blenkernel/intern/ocean.c b/source/blender/blenkernel/intern/ocean.c
index 5a755058963..c5179e5a428 100644
--- a/source/blender/blenkernel/intern/ocean.c
+++ b/source/blender/blenkernel/intern/ocean.c
@@ -502,7 +502,7 @@ typedef struct OceanSimulateData {
 	float chop_amount;
 } OceanSimulateData;
 
-static void ocean_compute_htilda(void *userdata, void *UNUSED(userdata_chunk), int i)
+static void ocean_compute_htilda(void *userdata, const int i)
 {
 	OceanSimulateData *osd = userdata;
 	const Ocean *o = osd->o;
@@ -748,7 +748,7 @@ void BKE_ocean_simulate(struct Ocean *o, float t, float scale, float chop_amount
 	 * This is not optimal in all cases, but remains reasonably simple and should be OK most of the time. */
 
 	/* compute a new htilda */
-	BLI_task_parallel_range(0, o->_M, &osd, ocean_compute_htilda);
+	BLI_task_parallel_range(0, o->_M, &osd, ocean_compute_htilda, o->_M > 16);
 
 	if (o->_do_disp_y) {
 		BLI_task_pool_push(pool, ocean_compute_displacement_y, NULL, false, TASK_PRIORITY_HIGH);
diff --git a/source/blender/blenlib/BLI_task.h b/source/blender/blenlib/BLI_task.h
index 7b9a3c59430..63a07957336 100644
--- a/source/blender/blenlib/BLI_task.h
+++ b/source/blender/blenlib/BLI_task.h
@@ -112,19 +112,20 @@ ThreadMutex *BLI_task_pool_user_mutex(TaskPool *pool);
 size_t BLI_task_pool_tasks_done(TaskPool *pool);
 
 /* Parallel for routines */
-typedef void (*TaskParallelRangeFunc)(void *userdata, void *userdata_chunk, int iter);
+typedef void (*TaskParallelRangeFunc)(void *userdata, const int iter);
+typedef void (*TaskParallelRangeFuncEx)(void *userdata, void *userdata_chunk, const int iter, const int thread_id);
 void BLI_task_parallel_range_ex(
         int start, int stop,
         void *userdata,
         void *userdata_chunk,
-        const size_t userdata_chunk_size,
-        TaskParallelRangeFunc func,
+        const size_t userdata_chunk_size, TaskParallelRangeFuncEx func_ex,
         const bool use_threading,
         const bool use_dynamic_scheduling);
 void BLI_task_parallel_range(
         int start, int stop,
         void *userdata,
-        TaskParallelRangeFunc func);
+        TaskParallelRangeFunc func,
+        const bool use_threading);
 
 #ifdef __cplusplus
 }
diff --git a/source/blender/blenlib/intern/BLI_kdopbvh.c b/source/blender/blenlib/intern/BLI_kdopbvh.c
index f1ed49f74e0..c4bf2ae6910 100644
--- a/source/blender/blenlib/intern/BLI_kdopbvh.c
+++ b/source/blender/blenlib/intern/BLI_kdopbvh.c
@@ -750,7 +750,7 @@ typedef struct BVHDivNodesData {
 	int first_of_next_level;
 } BVHDivNodesData;
 
-static void non_recursive_bvh_div_nodes_task_cb(void *userdata, void *UNUSED(userdata_chunk), int j)
+static void non_recursive_bvh_div_nodes_task_cb(void *userdata, const int j)
 {
 	BVHDivNodesData *data = userdata;
 
@@ -873,9 +873,9 @@ static void non_recursive_bvh_div_nodes(BVHTree *tree, BVHNode *branches_array,
 		cb_data.i = i;
 		cb_data.depth = depth;
 
-		BLI_task_parallel_range_ex(
-		            i, end_j, &cb_data, NULL, 0, non_recursive_bvh_div_nodes_task_cb,
-		            num_leafs > KDOPBVH_THREAD_LEAF_THRESHOLD, false);
+		BLI_task_parallel_range(
+		            i, end_j, &cb_data, non_recursive_bvh_div_nodes_task_cb,
+		            num_leafs > KDOPBVH_THREAD_LEAF_THRESHOLD);
 	}
 }
 
@@ -1195,7 +1195,7 @@ int BLI_bvhtree_overlap_thread_num(const BVHTree *tree)
 	return (int)MIN2(tree->tree_type, tree->nodes[tree->totleaf]->totnode);
 }
 
-static void bvhtree_overlap_task_cb(void *userdata, void *UNUSED(userdata_chunk), int j)
+static void bvhtree_overlap_task_cb(void *userdata, const int j)
 {
 	BVHOverlapData_Thread *data = &((BVHOverlapData_Thread *)userdata)[j];
 	BVHOverlapData_Shared *data_shared = data->shared;
@@ -1260,9 +1260,9 @@ BVHTreeOverlap *BLI_bvhtree_overlap(
 		data[j].thread = j;
 	}
 
-	BLI_task_parallel_range_ex(
-	            0, thread_num, data, NULL, 0, bvhtree_overlap_task_cb,
-	            tree1->totleaf > KDOPBVH_THREAD_LEAF_THRESHOLD, false);
+	BLI_task_parallel_range(
+	            0, thread_num, data, bvhtree_overlap_task_cb,
+	            tree1->totleaf > KDOPBVH_THREAD_LEAF_THRESHOLD);
 	
 	for (j = 0; j < thread_num; j++)
 		total += BLI_stack_count(data[j].overlap);
diff --git a/source/blender/blenlib/intern/math_statistics.c b/source/blender/blenlib/intern/math_statistics.c
index 97c224e0878..fbd6563e039 100644
--- a/source/blender/blenlib/intern/math_statistics.c
+++ b/source/blender/blenlib/intern/math_statistics.c
@@ -46,7 +46,7 @@ typedef struct CovarianceData {
 	int nbr_cos_vn;
 } CovarianceData;
 
-static void covariance_m_vn_ex_task_cb(void *userdata, void *UNUSED(userdata_chunk), int a)
+static void covariance_m_vn_ex_task_cb(void *userdata, const int a)
 {
 	CovarianceData *data = userdata;
 	const float *cos_vn = data->cos_vn;
@@ -117,8 +117,8 @@ void BLI_covariance_m_vn_ex(
 	    .covfac = covfac, .n = n, .nbr_cos_vn = nbr_cos_vn,
 	};
 
-	BLI_task_parallel_range_ex(
-	            0, n * n, &data, NULL, 0, covariance_m_vn_ex_task_cb, (nbr_cos_vn * n * n) >= 10000, false);
+	BLI_task_parallel_range(
+	            0, n * n, &data, covariance_m_vn_ex_task_cb, (nbr_cos_vn * n * n) >= 10000);
 }
 
 /**
diff --git a/source/blender/blenlib/intern/task.c b/source/blender/blenlib/intern/task.c
index 2be688a3d8c..f0edcc73345 100644
--- a/source/blender/blenlib/intern/task.c
+++ b/source/blender/blenlib/intern/task.c
@@ -584,7 +584,9 @@ typedef struct ParallelRangeState {
 	void *userdata;
 	void *userdata_chunk;
 	size_t userdata_chunk_size;
+
 	TaskParallelRangeFunc func;
+	TaskParallelRangeFuncEx func_ex;
 
 	int iter;
 	int chunk_size;
@@ -610,23 +612,31 @@ BLI_INLINE bool parallel_range_next_iter_get(
 static void parallel_range_func(
         TaskPool * __restrict pool,
         void *UNUSED(taskdata),
-        int UNUSED(threadid))
+        int threadid)
 {
 	ParallelRangeState * __restrict state = BLI_task_pool_userdata(pool);
 	int iter, count;
 
-	const bool use_userdata_chunk = (state->userdata_chunk_size != 0) && (state->userdata_chunk != NULL);
+	const bool use_userdata_chunk = (state->func_ex != NULL) &&
+	                                (state->userdata_chunk_size != 0) && (state->userdata_chunk != NULL);
 	void *userdata_chunk = use_userdata_chunk ? MALLOCA(state->userdata_chunk_size) : NULL;
 
 	while (parallel_range_next_iter_get(state, &iter, &count)) {
 		int i;
 
-		if (use_userdata_chunk) {
-			memcpy(userdata_chunk, state->userdata_chunk, state->userdata_chunk_size);
-		}
+		if (state->func_ex) {
+			if (use_userdata_chunk) {
+				memcpy(userdata_chunk, state->userdata_chunk, state->userdata_chunk_size);
+			}
 
-		for (i = 0; i < count; ++i) {
-			state->func(state->userdata, userdata_chunk, iter + i);
+			for (i = 0; i < count; ++i) {
+				state->func_ex(state->userdata, userdata_chunk, iter + i, threadid);
+			}
+		}
+		else {
+			for (i = 0; i < count; ++i) {
+				state->func(state->userdata, iter + i);
+			}
 		}
 	}
 
@@ -642,18 +652,20 @@ static void parallel_range_func(
  * \param userdata_chunk Optional, each instance of looping chunks will get a copy of this data
  *                       (similar to OpenMP's firstprivate).
  * \param userdata_chunk_size Memory size of \a userdata_chunk.
- * \param func Callback function.
+ * \param func Callback function (simple version).
+ * \param func_ex Callback function (advanced version).
  * \param use_threading If \a true, actually split-execute loop in threads, else just do a sequential forloop
  *                      (allows caller to use any kind of test to switch on parallelization or not).
  * \param use_dynamic_scheduling If \a true, the whole range is divided in a lot of small chunks (of size 32 currently),
  *                               otherwise whole range is split in a few big chunks (num_threads * 2 chunks currently).
  */
-void BLI_task_parallel_range_ex(
+static void task_parallel_range_ex(
         int start, int stop,
         void *userdata,
         void *userdata_chunk,
         const size_t userdata_chunk_size,
         TaskParallelRangeFunc func,
+        TaskParallelRangeFuncEx func_ex,
         const bool use_threading,
         const bool use_dynamic_scheduling)
 {
@@ -666,25 +678,37 @@ void BLI_task_parallel_range_ex(
 		return;
 	}
 
-	BLI_assert(start <= stop);
+	BLI_assert(start < stop);
+	if (userdata_chunk_size != 0) {
+		BLI_assert(func_ex != NULL && func == NULL);
+		BLI_assert(userdata_chunk != NULL);
+	}
 
 	/* If it's not enough data to be crunched, don't bother with tasks at all,
 	 * do everything from the main thread.
 	 */
 	if (!use_threading) {
-		const bool use_userdata_chunk = (userdata_chunk_size != 0) && (userdata_chunk != NULL);
-		void *userdata_chunk_local = NULL;
+		if (func_ex) {
+			const bool use_userdata_chunk = (userdata_chunk_size != 0) && (userdata_chunk != NULL);
+			void *userdata_chunk_local = NULL;
 
-		if (use_userdata_chunk) {
-			userdata_chunk_local = MALLOCA(userdata_chunk_size);
-			memcpy(userdata_chunk_local, userdata_chunk, userdata_chunk_size);
-		}
+			if (use_userdata_chunk) {
+				userdata_chunk_local = MALLOCA(userdata_chunk_size);
+				memcpy(userdata_chunk_local, userdata_chunk, userdata_chunk_size);
+			}
 
-		for (i = start; i < stop; ++i) {
-			func(userdata, userdata_chunk_local, i);
+			for (i = start; i < stop; ++i) {
+				func_ex(userdata, userdata_chunk, i, 0);
+			}
+
+			MALLOCA_FREE(userdata_chunk_local, userdata_chunk_size);
+		}
+		else {
+			for (i = start; i < stop; ++i) {
+				func(userdata, i);
+			}
 		}
 
-		MALLOCA_FREE(userdata_chunk_local, userdata_chunk_size);
 		return;
 	}
 
@@ -705,6 +729,7 @@ void BLI_task_parallel_range_ex(
 	state.userdata_chunk = userdata_chunk;
 	state.userdata_chunk_size = userdata_chunk_size;
 	state.func = func;
+	state.func_ex = func_ex;
 	state.iter = start;
 	if (use_dynamic_scheduling) {
 		state.chunk_size = 32;
@@ -729,15 +754,46 @@ void BLI_task_parallel_range_ex(
 }
 
 /**
+ * This function allows to parallelized for loops in a similar way to OpenMP's 'parallel for' statement.
+ *
+ * \param start First index to process.
+ * \param stop Index to stop looping (excluded).
+ * \param userdata Common userdata passed to all instances of \a func.
+ * \param userdata_chunk Optional, each instance of looping chunks will get a copy of this data
+ *                       (similar to OpenMP's firstprivate).
+ * \param userdata_chunk_size Memory size of \a userdata_chunk.
+ * \param func Callback function (simple version).
+ * \param func_ex Callback function (advanced version).
+ * \param use_threading If \a true, actually split-execute loop in threads, else just do a sequential forloop
+ *                      (allows caller to use any kind of test to switch on parallelization or not).
+ * \param use_dynamic_scheduling If \a true, the whole range is divided in a lot of small chunks (of size 32 currently),
+ *                               otherwise whole range is split in a few big chunks (num_threads * 2 chunks currently).
+ */
+void BLI_task_parallel_range_ex(
+        int start, int stop,
+        void *userdata,
+        void *userdata_chunk,
+        const size_t userdata_chunk_size,
+        TaskParallelRangeFuncEx func_ex,
+        const bool use_threading,
+        const bool use_dynamic_scheduling)
+{
+	task_parallel_range_ex(
+	            start, stop, userdata, userdata_chunk, userdata_chunk_size, NULL, func_ex,
+	            use_threading, use_dynamic_scheduling);
+}
+
+/**
  * A simpler version of \a BLI_task_parallel_range_ex, which does not use \a use_dynamic_scheduling,
- * has a \a range_threshold of 64, and does not handle 'firstprivate'-like \a userdata_chunk.
+ * and does not handle 'firstprivate'-like \a userdata_chunk.
  */
 void BLI_task_parallel_range(
         int start, int stop,
         void *userdata,
-        TaskParallelRangeFunc func)
+        TaskParallelRangeFunc func,
+		const bool use_threading)
 {
-	BLI_task_parallel_range_ex(start, stop, userdata, NULL, 0, func, (stop - start) > 64, false);
+	task_parallel_range_ex(start, stop, userdata, NULL, 0, func, NULL, use_threading, false);
 }
 
 #undef MALLOCA
diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index 8406f65dbe9..3ecc21de97f 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -449,7 +449,7 @@ typedef struct SculptThreadedTaskData {
 	ThreadMutex mutex;
 } SculptThreadedTaskData;
 
-static void paint_mesh_restore_co_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void paint_mesh_restore_co_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -511,8 +511,9 @@ static void paint_mesh_restore_co(Sculpt *sd, Object *ob)
 		.sd = sd, .ob = ob, .brush = brush, .nodes = nodes,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, paint_mesh_restore_co_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && !ss->bm && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, paint_mesh_restore_co_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && !ss->bm && totnode > SCULPT_OMP_LIMIT));
 
 	if (nodes)
 		MEM_freeN(nodes);
@@ -819,7 +820,7 @@ static float calc_symmetry_feather(Sculpt *sd, StrokeCache *cache)
  * \note These are all _very_ similar, when changing one, check others.
  * \{ */
 
-static void calc_area_normal_and_center_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void calc_area_normal_and_center_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -966,8 +967,9 @@ static void calc_area_center(
 	};
 	BLI_mutex_init(&data.mutex);
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, calc_area_normal_and_center_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, calc_area_normal_and_center_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 
 	BLI_mutex_end(&data.mutex);
 
@@ -1005,8 +1007,9 @@ static void calc_area_normal(
 	};
 	BLI_mutex_init(&data.mutex);
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, calc_area_normal_and_center_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, calc_area_normal_and_center_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 
 	BLI_mutex_end(&data.mutex);
 
@@ -1042,8 +1045,9 @@ static void calc_area_normal_and_center(
 	};
 	BLI_mutex_init(&data.mutex);
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, calc_area_normal_and_center_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, calc_area_normal_and_center_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 
 	BLI_mutex_end(&data.mutex);
 
@@ -1651,7 +1655,8 @@ static void do_smooth_brush_bmesh_task_cb(void *userdata, void *UNUSED(userdata_
 	BKE_pbvh_vertex_iter_end;
 }
 
-static void do_smooth_brush_multires_task_cb(void *userdata, void *userdata_chunk, int n)
+static void do_smooth_brush_multires_task_cb_ex(
+        void *userdata, void *userdata_chunk, const int n, const int UNUSED(thread_id))
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptDoBrushSmoothGridDataChunk *data_chunk = userdata_chunk;
@@ -1836,21 +1841,21 @@ static void smooth(
 				size += sizeof(*data_chunk);
 
 				BLI_task_parallel_range_ex(
-				            0, totnode, &data, data_chunk, size, do_smooth_brush_multires_task_cb,
+				            0, totnode, &data, data_chunk, size, do_smooth_brush_multires_task_cb_ex,
 				            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
 
 				MEM_freeN(data_chunk);
 				break;
 			}
 			case PBVH_FACES:
-				BLI_task_parallel_range_ex(
-				            0, totnode, &data, NULL, 0, do_smooth_brush_mesh_task_cb,
-				            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+				BLI_task_parallel_range(
+				            0, totnode, &data, do_smooth_brush_mesh_task_cb,
+				            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 				break;
 			case PBVH_BMESH:
-				BLI_task_parallel_range_ex(
-				            0, totnode, &data, NULL, 0, do_smooth_brush_bmesh_task_cb,
-				            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+				BLI_task_parallel_range(
+				            0, totnode, &data, do_smooth_brush_bmesh_task_cb,
+				            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 				break;
 		}
 
@@ -1865,7 +1870,7 @@ static void do_smooth_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnod
 	smooth(sd, ob, nodes, totnode, ss->cache->bstrength, false);
 }
 
-static void do_mask_brush_draw_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_mask_brush_draw_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -1901,8 +1906,9 @@ static void do_mask_brush_draw(Sculpt *sd, Object *ob, PBVHNode **nodes, int tot
 	    .sd = sd, .ob = ob, .brush = brush, .nodes = nodes,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_mask_brush_draw_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_mask_brush_draw_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
 static void do_mask_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
@@ -1920,7 +1926,7 @@ static void do_mask_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
 	}
 }
 
-static void do_draw_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_draw_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -1968,11 +1974,12 @@ static void do_draw_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
 	    .offset = offset,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_draw_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_draw_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_crease_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_crease_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2054,11 +2061,12 @@ static void do_crease_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnod
 	    .spvc = &spvc, .offset = offset, .flippedbstrength = flippedbstrength,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_crease_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_crease_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_pinch_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_pinch_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2098,11 +2106,12 @@ static void do_pinch_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode
 	    .sd = sd, .ob = ob, .brush = brush, .nodes = nodes,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_pinch_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_pinch_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_grab_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_grab_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2160,11 +2169,12 @@ static void do_grab_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
 	    .grab_delta = grab_delta,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_grab_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_grab_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_nudge_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_nudge_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2212,11 +2222,12 @@ static void do_nudge_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode
 	    .cono = cono,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_nudge_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_nudge_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_snake_hook_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_snake_hook_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2273,11 +2284,12 @@ static void do_snake_hook_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int to
 	    .grab_delta = grab_delta,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_snake_hook_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_snake_hook_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_thumb_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_thumb_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2330,11 +2342,12 @@ static void do_thumb_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode
 	    .cono = cono,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_thumb_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_thumb_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_rotate_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_rotate_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2388,11 +2401,12 @@ static void do_rotate_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnod
 	    .angle = angle,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_rotate_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_rotate_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_layer_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_layer_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2469,13 +2483,14 @@ static void do_layer_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode
 	};
 	BLI_mutex_init(&data.mutex);
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_layer_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_layer_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 
 	BLI_mutex_end(&data.mutex);
 }
 
-static void do_inflate_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_inflate_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2520,8 +2535,9 @@ static void do_inflate_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totno
 	    .sd = sd, .ob = ob, .brush = brush, .nodes = nodes,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_inflate_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_inflate_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
 static void calc_sculpt_plane(
@@ -2649,7 +2665,7 @@ static float get_offset(Sculpt *sd, SculptSession *ss)
 	return rv;
 }
 
-static void do_flatten_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_flatten_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2717,11 +2733,12 @@ static void do_flatten_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totno
 	    .area_no = area_no, .area_co = area_co,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_flatten_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_flatten_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_clay_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_clay_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2797,11 +2814,12 @@ static void do_clay_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
 	    .area_no = area_no, .area_co = area_co,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_clay_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_clay_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_clay_strips_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_clay_strips_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2904,11 +2922,12 @@ static void do_clay_strips_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int t
 	    .area_no_sp = area_no_sp, .area_co = area_co, .mat = mat,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_clay_strips_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_clay_strips_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_fill_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_fill_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -2980,11 +2999,12 @@ static void do_fill_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
 	    .area_no = area_no, .area_co = area_co,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_fill_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_fill_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_scrape_brush_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_scrape_brush_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -3055,11 +3075,12 @@ static void do_scrape_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnod
 	    .area_no = area_no, .area_co = area_co,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_scrape_brush_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_scrape_brush_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
-static void do_gravity_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_gravity_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -3108,8 +3129,9 @@ static void do_gravity(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode, fl
 	    .offset = offset,
 	};
 
-	BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, do_gravity_task_cb,
-	                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+	BLI_task_parallel_range(
+	            0, totnode, &data, do_gravity_task_cb,
+	            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 }
 
 
@@ -3219,7 +3241,7 @@ static void sculpt_topology_update(Sculpt *sd, Object *ob, Brush *brush, Unified
 	}
 }
 
-static void do_brush_action_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void do_brush_action_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 
@@ -3250,8 +3272,9 @@ static void do_brush_action(Sculpt *sd, Object *ob, Brush *brush, UnifiedPaintSe
 			.sd = sd, .ob = ob, .brush = brush, .nodes = nodes,
 		};
 
-		BLI_task_parallel_range_ex(0, totnode, &task_data, NULL, 0, do_brush_action_task_cb,
-		                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+		BLI_task_parallel_range(
+		            0, totnode, &task_data, do_brush_action_task_cb,
+		            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 
 		if (sculpt_brush_needs_normal(brush))
 			update_sculpt_normal(sd, ob, nodes, totnode);
@@ -3363,7 +3386,7 @@ static void sculpt_flush_pbvhvert_deform(Object *ob, PBVHVertexIter *vd)
 		copy_v3_v3(me->mvert[index].co, newco);
 }
 
-static void sculpt_combine_proxies_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void sculpt_combine_proxies_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -3430,8 +3453,9 @@ static void sculpt_combine_proxies(Sculpt *sd, Object *ob)
 			.sd = sd, .ob = ob, .brush = brush, .nodes = nodes,
 		};
 
-		BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, sculpt_combine_proxies_task_cb,
-		                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+		BLI_task_parallel_range(
+		            0, totnode, &data, sculpt_combine_proxies_task_cb,
+		            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 	}
 
 	if (nodes)
@@ -3457,7 +3481,7 @@ static void sculpt_update_keyblock(Object *ob)
 	}
 }
 
-static void sculpt_flush_stroke_deform_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void sculpt_flush_stroke_deform_task_cb(void *userdata, const int n)
 {
 	SculptThreadedTaskData *data = userdata;
 	SculptSession *ss = data->ob->sculpt;
@@ -3510,8 +3534,9 @@ static void sculpt_flush_stroke_deform(Sculpt *sd, Object *ob)
 			.vertCos = vertCos,
 		};
 
-		BLI_task_parallel_range_ex(0, totnode, &data, NULL, 0, sculpt_flush_stroke_deform_task_cb,
-		                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+		BLI_task_parallel_range(
+		            0, totnode, &data, sculpt_flush_stroke_deform_task_cb,
+		            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 
 		if (vertCos) {
 			sculpt_vertcos_to_key(ob, ss->kb, vertCos);
diff --git a/source/blender/editors/sculpt_paint/sculpt_undo.c b/source/blender/editors/sculpt_paint/sculpt_undo.c
index 0c16041b141..8fcac496e5e 100644
--- a/source/blender/editors/sculpt_paint/sculpt_undo.c
+++ b/source/blender/editors/sculpt_paint/sculpt_undo.c
@@ -266,7 +266,7 @@ static int sculpt_undo_restore_mask(bContext *C, DerivedMesh *dm, SculptUndoNode
 	return 1;
 }
 
-static void sculpt_undo_bmesh_restore_generic_task_cb(void *userdata, void *UNUSED(userdata_chunk), int n)
+static void sculpt_undo_bmesh_restore_generic_task_cb(void *userdata, const int n)
 {
 	PBVHNode **nodes = userdata;
 
@@ -294,8 +294,9 @@ static void sculpt_undo_bmesh_restore_generic(bContext *C,
 
 		BKE_pbvh_search_gather(ss->pbvh, NULL, NULL, &nodes, &totnode);
 
-		BLI_task_parallel_range_ex(0, totnode, nodes, NULL, 0, sculpt_undo_bmesh_restore_generic_task_cb,
-		                           ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT), false);
+		BLI_task_parallel_range(
+		            0, totnode, nodes, sculpt_undo_bmesh_restore_generic_task_cb,
+		            ((sd->flags & SCULPT_USE_OPENMP) && totnode > SCULPT_OMP_LIMIT));
 
 		if (nodes)
 			MEM_freeN(nodes);
diff --git a/source/blender/modifiers/intern/MOD_meshdeform.c b/source/blender/modifiers/intern/MOD_meshdeform.c
index 5f2f51df528..e3c94a1a4df 100644
--- a/source/blender/modifiers/intern/MOD_meshdeform.c
+++ b/source/blender/modifiers/intern/MOD_meshdeform.c
@@ -234,7 +234,7 @@ typedef struct MeshdeformUserdata {
 	float (*icagemat)[3];
 } MeshdeformUserdata;
 
-static void meshdeform_vert_task(void *userdata, void *UNUSED(userdata_chunck), int iter)
+static void meshdeform_vert_task(void *userdata, const int iter)
 {
 	MeshdeformUserdata *data = userdata;
 	/*const*/ MeshDeformModifierData *mmd = data->mmd;
@@ -413,7 +413,7 @@ static void meshdeformModifier_do(
 	data.icagemat = icagemat;
 
 	/* Do deformation. */
-	BLI_task_parallel_range(0, totvert, &data, meshdeform_vert_task);
+	BLI_task_parallel_range(0, totvert, &data, meshdeform_vert_task, totvert > 1000);
 
 	/* release cage derivedmesh */
 	MEM_freeN(dco);
diff --git a/source/blender/modifiers/intern/MOD_ocean.c b/source/blender/modifiers/intern/MOD_ocean.c
index 18fbc99d887..a90a51e9ddc 100644
--- a/source/blender/modifiers/intern/MOD_ocean.c
+++ b/source/blender/modifiers/intern/MOD_ocean.c
@@ -280,7 +280,7 @@ typedef struct GenerateOceanGeometryData {
 	float ix, iy;
 } GenerateOceanGeometryData;
 
-static void generate_ocean_geometry_vertices(void *userdata, void *UNUSED(userdata_chunk), int y)
+static void generate_ocean_geometry_vertices(void *userdata, const int y)
 {
 	GenerateOceanGeometryData *gogd = userdata;
 	int x;
@@ -294,7 +294,7 @@ static void generate_ocean_geometry_vertices(void *userdata, void *UNUSED(userda
 	}
 }
 
-static void generate_ocean_geometry_polygons(void *userdata, void *UNUSED(userdata_chunk), int y)
+static void generate_ocean_geometry_polygons(void *userdata, const int y)
 {
 	GenerateOceanGeometryData *gogd = userdata;
 	int x;
@@ -324,7 +324,7 @@ static void generate_ocean_geometry_polygons(void *userdata, void *UNUSED(userda
 	}
 }
 
-static void generate_ocean_geometry_uvs(void *userdata, void *UNUSED(userdata_chunk), int y)
+static void generate_ocean_geometry_uvs(void *userdata, const int y)
 {
 	GenerateOceanGeometryData *gogd = userdata;
 	int x;
@@ -360,6 +360,8 @@ static DerivedMesh *generate_ocean_geometry(OceanModifierData *omd)
 	int num_verts;
 	int num_polys;
 
+	const bool use_threading = omd->resolution > 4;
+
 	gogd.rx = omd->resolution * omd->resolution;
 	gogd.ry = omd->resolution * omd->resolution;
 	gogd.res_x = gogd.rx * omd->repeat_x;
@@ -385,10 +387,10 @@ static DerivedMesh *generate_ocean_geometry(OceanModifierData *omd)
 	gogd.origindex = CustomData_get_layer(&result->polyData, CD_ORIGINDEX);
 
 	/* create vertices */
-	BLI_task_parallel_range(0, gogd.res_y + 1, &gogd, generate_ocean_geometry_vertices);
+	BLI_task_parallel_range(0, gogd.res_y + 1, &gogd, generate_ocean_geometry_vertices, use_threading);
 
 	/* create faces */
-	BLI_task_parallel_range(0, gogd.res_y, &gogd, generate_ocean_geometry_polygons);
+	BLI_task_parallel_range(0, gogd.res_y, &gogd, generate_ocean_geometry_polygons, use_threading);
 
 	CDDM_calc_edges(result);
 
@@ -401,7 +403,7 @@ static DerivedMesh *generate_ocean_geometry(OceanModifierData *omd)
 			gogd.ix = 1.0 / gogd.rx;
 			gogd.iy = 1.0 / gogd.ry;
 
-			BLI_task_parallel_range(0, gogd.res_y, &gogd, generate_ocean_geometry_uvs);
+			BLI_task_parallel_range(0, gogd.res_y, &gogd, generate_ocean_geometry_uvs, use_threading);
 		}
 	}
 
diff --git a/source/blender/modifiers/intern/MOD_uvwarp.c b/source/blender/modifiers/intern/MOD_uvwarp.c
index 3b549ec77d3..89994c3ae22 100644
--- a/source/blender/modifiers/intern/MOD_uvwarp.c
+++ b/source/blender/modifiers/intern/MOD_uvwarp.c
@@ -112,7 +112,7 @@ typedef struct UVWarpData {
 	int axis_v;
 } UVWarpData;
 
-static void uv_warp_compute(void *userdata, void *UNUSED(userdata_chunk), int i)
+static void uv_warp_compute(void *userdata, const int i)
 {
 	const UVWarpData *data = userdata;
 
@@ -210,7 +210,7 @@ static DerivedMesh *applyModifier(ModifierData *md, Object *ob,
 	UVWarpData data = {.mpoly = mpoly, .mloop = mloop, .mloopuv = mloopuv,
 	                   .dvert = dvert, .defgrp_index = defgrp_index,
 	                   .warp_mat = warp_mat, .axis_u = axis_u, .axis_v = axis_v};
-	BLI_task_parallel_range_ex(0, numPolys, &data, NULL, 0, uv_warp_compute, numPolys > 1000, false);
+	BLI_task_parallel_range(0, numPolys, &data, uv_warp_compute, numPolys > 1000);
 
 	dm->dirty |= DM_DIRTY_TESS_CDLAYERS;
 
diff --git a/source/blender/modifiers/intern/MOD_weightvgproximity.c b/source/blender/modifiers/intern/MOD_weightvgproximity.c
index be86dfe4a92..f126e499fc2 100644
--- a/source/blender/modifiers/intern/MOD_weightvgproximity.c
+++ b/source/blender/modifiers/intern/MOD_weightvgproximity.c
@@ -89,7 +89,7 @@ typedef struct Vert2GeomDataChunk {
 /**
  * Callback used by BLI_task 'for loop' helper.
  */
-static void vert2geom_task_cb(void *userdata, void *userdata_chunk, int iter)
+static void vert2geom_task_cb_ex(void *userdata, void *userdata_chunk, const int iter, const int UNUSED(thread_id))
 {
 	Vert2GeomData *data = userdata;
 	Vert2GeomDataChunk *data_chunk = userdata_chunk;
@@ -177,7 +177,8 @@ static void get_vert2geom_distance(int numVerts, float (*v_cos)[3],
 	data.dist[2] = dist_f;
 
 	BLI_task_parallel_range_ex(
-	            0, numVerts, &data, &data_chunk, sizeof(data_chunk), vert2geom_task_cb, numVerts > 10000, false);
+	            0, numVerts, &data, &data_chunk, sizeof(data_chunk), vert2geom_task_cb_ex,
+	            numVerts > 10000, false);
 
 	if (dist_v)
 		free_bvhtree_from_mesh(&treeData_v);