diff --git a/src/engine.c b/src/engine.c
index 75c25cdb8b5f0450deb6f05e4c896c6ebe24305a..43eb864cb93f6821e55efc670de2a607cd677f5e 100644
--- a/src/engine.c
+++ b/src/engine.c
@@ -1814,9 +1814,15 @@ void engine_make_external_gravity_tasks(struct engine *e) {
* Additional loop over neighbours can later be added by simply duplicating
* all the tasks created by this function.
*
- * @param e The #engine.
+ * @param map_data Offset of first two indices disguised as a pointer.
+ * @param num_elements Number of cells to traverse.
+ * @param extra_data The #engine.
*/
-void engine_make_hydroloop_tasks(struct engine *e) {
+void engine_make_hydroloop_tasks_mapper(void *map_data, int num_elements,
+ void *extra_data) {
+
+ /* Extract the engine pointer. */
+ struct engine *e = (struct engine *)extra_data;
struct space *s = e->s;
struct scheduler *sched = &e->sched;
@@ -1824,53 +1830,53 @@ void engine_make_hydroloop_tasks(struct engine *e) {
const int *cdim = s->cdim;
struct cell *cells = s->cells_top;
- /* Run through the highest level of cells and add pairs. */
- for (int i = 0; i < cdim[0]; i++) {
- for (int j = 0; j < cdim[1]; j++) {
- for (int k = 0; k < cdim[2]; k++) {
-
- /* Get the cell */
- const int cid = cell_getid(cdim, i, j, k);
- struct cell *ci = &cells[cid];
-
- /* Skip cells without hydro particles */
- if (ci->count == 0) continue;
+ /* Loop through the elements, which are just byte offsets from NULL. */
+ for (int ind = 0; ind < num_elements; ind++) {
- /* If the cells is local build a self-interaction */
- if (ci->nodeID == nodeID)
- scheduler_addtask(sched, task_type_self, task_subtype_density, 0, 0,
- ci, NULL);
-
- /* Now loop over all the neighbours of this cell */
- for (int ii = -1; ii < 2; ii++) {
- int iii = i + ii;
- if (!s->periodic && (iii < 0 || iii >= cdim[0])) continue;
- iii = (iii + cdim[0]) % cdim[0];
- for (int jj = -1; jj < 2; jj++) {
- int jjj = j + jj;
- if (!s->periodic && (jjj < 0 || jjj >= cdim[1])) continue;
- jjj = (jjj + cdim[1]) % cdim[1];
- for (int kk = -1; kk < 2; kk++) {
- int kkk = k + kk;
- if (!s->periodic && (kkk < 0 || kkk >= cdim[2])) continue;
- kkk = (kkk + cdim[2]) % cdim[2];
-
- /* Get the neighbouring cell */
- const int cjd = cell_getid(cdim, iii, jjj, kkk);
- struct cell *cj = &cells[cjd];
+ /* Get the cell index. */
+ const int cid = (size_t)(map_data + ind);
+ const int i = cid / (cdim[1] * cdim[0]);
+ const int j = (cid / cdim[0]) % cdim[1];
+ const int k = cid % (cdim[0] * cdim[1]);
- /* Is that neighbour local and does it have particles ? */
- if (cid >= cjd || cj->count == 0 ||
- (ci->nodeID != nodeID && cj->nodeID != nodeID))
- continue;
+ /* Get the cell */
+ struct cell *ci = &cells[cid];
- /* Construct the pair task */
- const int sid =
- sortlistID[(kk + 1) + 3 * ((jj + 1) + 3 * (ii + 1))];
- scheduler_addtask(sched, task_type_pair, task_subtype_density,
- sid, 0, ci, cj);
- }
- }
+ /* Skip cells without hydro particles */
+ if (ci->count == 0) continue;
+
+ /* If the cells is local build a self-interaction */
+ if (ci->nodeID == nodeID)
+ scheduler_addtask(sched, task_type_self, task_subtype_density, 0, 0, ci,
+ NULL);
+
+ /* Now loop over all the neighbours of this cell */
+ for (int ii = -1; ii < 2; ii++) {
+ int iii = i + ii;
+ if (!s->periodic && (iii < 0 || iii >= cdim[0])) continue;
+ iii = (iii + cdim[0]) % cdim[0];
+ for (int jj = -1; jj < 2; jj++) {
+ int jjj = j + jj;
+ if (!s->periodic && (jjj < 0 || jjj >= cdim[1])) continue;
+ jjj = (jjj + cdim[1]) % cdim[1];
+ for (int kk = -1; kk < 2; kk++) {
+ int kkk = k + kk;
+ if (!s->periodic && (kkk < 0 || kkk >= cdim[2])) continue;
+ kkk = (kkk + cdim[2]) % cdim[2];
+
+ /* Get the neighbouring cell */
+ const int cjd = cell_getid(cdim, iii, jjj, kkk);
+ struct cell *cj = &cells[cjd];
+
+ /* Is that neighbour local and does it have particles ? */
+ if (cid >= cjd || cj->count == 0 ||
+ (ci->nodeID != nodeID && cj->nodeID != nodeID))
+ continue;
+
+ /* Construct the pair task */
+ const int sid = sortlistID[(kk + 1) + 3 * ((jj + 1) + 3 * (ii + 1))];
+ scheduler_addtask(sched, task_type_pair, task_subtype_density, sid, 0,
+ ci, cj);
}
}
}
@@ -2175,7 +2181,7 @@ void engine_make_extra_hydroloop_tasks(struct engine *e) {
scheduler_addunlock(sched, t->ci->super->sorts, t);
#ifdef EXTRA_HYDRO_LOOP
- /* Start by constructing the task for the second and third hydro loop */
+ /* Start by constructing the task for the second and third hydro loop. */
struct task *t2 = scheduler_addtask(
sched, task_type_self, task_subtype_gradient, 0, 0, t->ci, NULL);
struct task *t3 = scheduler_addtask(
@@ -2424,7 +2430,10 @@ void engine_maketasks(struct engine *e) {
scheduler_reset(sched, s->tot_cells * engine_maxtaskspercell);
/* Construct the firt hydro loop over neighbours */
- if (e->policy & engine_policy_hydro) engine_make_hydroloop_tasks(e);
+ if (e->policy & engine_policy_hydro) {
+ threadpool_map(&e->threadpool, engine_make_hydroloop_tasks_mapper, NULL,
+ s->nr_cells, 1, 0, e);
+ }
/* Add the self gravity tasks. */
if (e->policy & engine_policy_self_gravity) engine_make_self_gravity_tasks(e);
@@ -2641,8 +2650,8 @@ void engine_marktasks_mapper(void *map_data, int num_elements,
scheduler_activate(s, l->t);
/* Drift the cell which will be sent at the level at which it is
- sent,
- i.e. drift the cell specified in the send task (l->t) itself. */
+ sent, i.e. drift the cell specified in the send task (l->t)
+ itself. */
cell_activate_drift_part(l->t->ci, s);
if (cell_is_active(cj, e)) {
@@ -2699,8 +2708,8 @@ void engine_marktasks_mapper(void *map_data, int num_elements,
scheduler_activate(s, l->t);
/* Drift the cell which will be sent at the level at which it is
- sent,
- i.e. drift the cell specified in the send task (l->t) itself. */
+ sent, i.e. drift the cell specified in the send task (l->t)
+ itself. */
cell_activate_drift_part(l->t->ci, s);
if (cell_is_active(ci, e)) {