Moved the particle drifting mapper from the runner to the engine.

src/engine.c

@@ -3136,6 +3136,32 @@ void engine_unskip(struct engine *e) {
             clocks_getunit());
 }
 
+/**
+ * @brief Mapper function to drift ALL particle types and multipoles forward in
+ * time.
+ *
+ * @param map_data An array of #cell%s.
+ * @param num_elements Chunk size.
+ * @param extra_data Pointer to an #engine.
+ */
+void engine_do_drift_all_mapper(void *map_data, int num_elements,
+                                void *extra_data) {
+
+  struct engine *e = (struct engine *)extra_data;
+  struct cell *cells = (struct cell *)map_data;
+
+  for (int ind = 0; ind < num_elements; ind++) {
+    struct cell *c = &cells[ind];
+    if (c != NULL && c->nodeID == e->nodeID) {
+      /* Drift all the particles */
+      cell_drift_particles(c, e);
+
+      /* Drift the multipole */
+      if (e->policy & engine_policy_self_gravity) cell_drift_multipole(c, e);
+    }
+  }
+}
+
 /**
  * @brief Drift *all* particles forward to the current time.
  *
@@ -3144,7 +3170,7 @@ void engine_unskip(struct engine *e) {
 void engine_drift_all(struct engine *e) {
 
   const ticks tic = getticks();
-  threadpool_map(&e->threadpool, runner_do_drift_all_mapper, e->s->cells_top,
+  threadpool_map(&e->threadpool, engine_do_drift_all_mapper, e->s->cells_top,
                  e->s->nr_cells, sizeof(struct cell), 1, e);
 
 #ifdef SWIFT_DEBUG_CHECKS

src/runner.c

@@ -819,31 +819,6 @@ void runner_do_drift_particles(struct runner *r, struct cell *c, int timer) {
   if (timer) TIMER_TOC(timer_drift);
 }
 
-/**
- * @brief Mapper function to drift ALL particle and g-particles forward in time.
- *
- * @param map_data An array of #cell%s.
- * @param num_elements Chunk size.
- * @param extra_data Pointer to an #engine.
- */
-void runner_do_drift_all_mapper(void *map_data, int num_elements,
-                                void *extra_data) {
-
-  struct engine *e = (struct engine *)extra_data;
-  struct cell *cells = (struct cell *)map_data;
-
-  for (int ind = 0; ind < num_elements; ind++) {
-    struct cell *c = &cells[ind];
-    if (c != NULL && c->nodeID == e->nodeID) {
-      /* Drift all the particles */
-      cell_drift_particles(c, e);
-
-      /* Drift the multipole */
-      if (e->policy & engine_policy_self_gravity) cell_drift_multipole(c, e);
-    }
-  }
-}
-
 /**
  * @brief Perform the first half-kick on all the active particles in a cell.
  *