runner.c 59.6 KB
Newer Older
1
/*******************************************************************************
2
 * This file is part of SWIFT.
3
 * Copyright (c) 2012 Pedro Gonnet (pedro.gonnet@durham.ac.uk)
4
5
6
7
 *                    Matthieu Schaller (matthieu.schaller@durham.ac.uk)
 *               2015 Peter W. Draper (p.w.draper@durham.ac.uk)
 *               2016 John A. Regan (john.a.regan@durham.ac.uk)
 *                    Tom Theuns (tom.theuns@durham.ac.uk)
8
 *
9
10
11
12
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
13
 *
14
15
16
17
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
18
 *
19
20
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
21
 *
22
 ******************************************************************************/
Pedro Gonnet's avatar
Pedro Gonnet committed
23

Pedro Gonnet's avatar
Pedro Gonnet committed
24
25
/* Config parameters. */
#include "../config.h"
Pedro Gonnet's avatar
Pedro Gonnet committed
26
27
28
29

/* Some standard headers. */
#include <float.h>
#include <limits.h>
30
#include <stdlib.h>
Pedro Gonnet's avatar
Pedro Gonnet committed
31

32
33
/* MPI headers. */
#ifdef WITH_MPI
34
#include <mpi.h>
35
36
#endif

37
38
39
/* This object's header. */
#include "runner.h"

Pedro Gonnet's avatar
Pedro Gonnet committed
40
/* Local headers. */
41
#include "active.h"
Matthieu Schaller's avatar
Matthieu Schaller committed
42
#include "approx_math.h"
43
#include "atomic.h"
44
#include "cell.h"
45
#include "const.h"
Stefan Arridge's avatar
Stefan Arridge committed
46
#include "cooling.h"
47
#include "debug.h"
Matthieu Schaller's avatar
Matthieu Schaller committed
48
#include "drift.h"
Pedro Gonnet's avatar
Pedro Gonnet committed
49
#include "engine.h"
50
#include "error.h"
51
52
#include "gravity.h"
#include "hydro.h"
Matthieu Schaller's avatar
Matthieu Schaller committed
53
#include "hydro_properties.h"
54
#include "kick.h"
55
#include "minmax.h"
56
#include "runner_doiact_fft.h"
James Willis's avatar
James Willis committed
57
#include "runner_doiact_vec.h"
58
#include "scheduler.h"
59
#include "sort_part.h"
60
#include "sourceterms.h"
61
#include "space.h"
62
#include "stars.h"
63
64
#include "task.h"
#include "timers.h"
65
#include "timestep.h"
Pedro Gonnet's avatar
Pedro Gonnet committed
66

67
/* Import the density loop functions. */
68
69
70
#define FUNCTION density
#include "runner_doiact.h"

71
/* Import the gradient loop functions (if required). */
72
73
74
75
76
77
#ifdef EXTRA_HYDRO_LOOP
#undef FUNCTION
#define FUNCTION gradient
#include "runner_doiact.h"
#endif

78
/* Import the force loop functions. */
79
80
81
82
#undef FUNCTION
#define FUNCTION force
#include "runner_doiact.h"

83
/* Import the gravity loop functions. */
84
#include "runner_doiact_fft.h"
85
#include "runner_doiact_grav.h"
86

Tom Theuns's avatar
Tom Theuns committed
87
/**
Tom Theuns's avatar
Tom Theuns committed
88
 * @brief Perform source terms
Tom Theuns's avatar
Tom Theuns committed
89
90
91
92
93
94
95
 *
 * @param r runner task
 * @param c cell
 * @param timer 1 if the time is to be recorded.
 */
void runner_do_sourceterms(struct runner *r, struct cell *c, int timer) {
  const int count = c->count;
96
  const double cell_min[3] = {c->loc[0], c->loc[1], c->loc[2]};
Tom Theuns's avatar
Tom Theuns committed
97
  const double cell_width[3] = {c->width[0], c->width[1], c->width[2]};
Tom Theuns's avatar
Tom Theuns committed
98
  struct sourceterms *sourceterms = r->e->sourceterms;
99
  const int dimen = 3;
Tom Theuns's avatar
Tom Theuns committed
100
101
102
103
104
105
106

  TIMER_TIC;

  /* Recurse? */
  if (c->split) {
    for (int k = 0; k < 8; k++)
      if (c->progeny[k] != NULL) runner_do_sourceterms(r, c->progeny[k], 0);
107
  } else {
Tom Theuns's avatar
Tom Theuns committed
108

109
    if (count > 0) {
Tom Theuns's avatar
Tom Theuns committed
110

111
112
113
114
115
116
      /* do sourceterms in this cell? */
      const int incell =
          sourceterms_test_cell(cell_min, cell_width, sourceterms, dimen);
      if (incell == 1) {
        sourceterms_apply(r, sourceterms, c);
      }
Tom Theuns's avatar
Tom Theuns committed
117
118
    }
  }
Tom Theuns's avatar
Tom Theuns committed
119
120
121
122

  if (timer) TIMER_TOC(timer_dosource);
}

Tom Theuns's avatar
Tom Theuns committed
123
124
125
/**
 * @brief Calculate gravity acceleration from external potential
 *
Matthieu Schaller's avatar
Matthieu Schaller committed
126
127
128
 * @param r runner task
 * @param c cell
 * @param timer 1 if the time is to be recorded.
Tom Theuns's avatar
Tom Theuns committed
129
 */
130
void runner_do_grav_external(struct runner *r, struct cell *c, int timer) {
Tom Theuns's avatar
Tom Theuns committed
131

Matthieu Schaller's avatar
Matthieu Schaller committed
132
133
  struct gpart *restrict gparts = c->gparts;
  const int gcount = c->gcount;
134
135
136
  const struct engine *e = r->e;
  const struct external_potential *potential = e->external_potential;
  const struct phys_const *constants = e->physical_constants;
137
  const double time = r->e->time;
Matthieu Schaller's avatar
Matthieu Schaller committed
138

139
  TIMER_TIC;
Tom Theuns's avatar
Tom Theuns committed
140

141
  /* Anything to do here? */
142
  if (!cell_is_active_gravity(c, e)) return;
143

Tom Theuns's avatar
Tom Theuns committed
144
145
  /* Recurse? */
  if (c->split) {
Matthieu Schaller's avatar
Matthieu Schaller committed
146
    for (int k = 0; k < 8; k++)
147
      if (c->progeny[k] != NULL) runner_do_grav_external(r, c->progeny[k], 0);
148
  } else {
149

150
151
    /* Loop over the gparts in this cell. */
    for (int i = 0; i < gcount; i++) {
152

153
154
      /* Get a direct pointer on the part. */
      struct gpart *restrict gp = &gparts[i];
Matthieu Schaller's avatar
Matthieu Schaller committed
155

156
      /* Is this part within the time step? */
157
      if (gpart_is_active(gp, e)) {
158
159
        external_gravity_acceleration(time, potential, constants, gp);
      }
160
    }
161
  }
Matthieu Schaller's avatar
Matthieu Schaller committed
162

163
  if (timer) TIMER_TOC(timer_dograv_external);
Tom Theuns's avatar
Tom Theuns committed
164
165
}

Stefan Arridge's avatar
Stefan Arridge committed
166
/**
167
168
 * @brief Calculate change in thermal state of particles induced
 * by radiative cooling and heating.
Stefan Arridge's avatar
Stefan Arridge committed
169
170
171
172
173
174
175
176
 *
 * @param r runner task
 * @param c cell
 * @param timer 1 if the time is to be recorded.
 */
void runner_do_cooling(struct runner *r, struct cell *c, int timer) {

  struct part *restrict parts = c->parts;
177
  struct xpart *restrict xparts = c->xparts;
Stefan Arridge's avatar
Stefan Arridge committed
178
  const int count = c->count;
179
180
181
  const struct engine *e = r->e;
  const struct cooling_function_data *cooling_func = e->cooling_func;
  const struct phys_const *constants = e->physical_constants;
182
  const struct unit_system *us = e->internal_units;
183
  const double timeBase = e->timeBase;
Stefan Arridge's avatar
Stefan Arridge committed
184
185
186

  TIMER_TIC;

187
  /* Anything to do here? */
188
  if (!cell_is_active_hydro(c, e)) return;
189

Stefan Arridge's avatar
Stefan Arridge committed
190
191
192
193
  /* Recurse? */
  if (c->split) {
    for (int k = 0; k < 8; k++)
      if (c->progeny[k] != NULL) runner_do_cooling(r, c->progeny[k], 0);
194
  } else {
Stefan Arridge's avatar
Stefan Arridge committed
195

196
197
    /* Loop over the parts in this cell. */
    for (int i = 0; i < count; i++) {
Stefan Arridge's avatar
Stefan Arridge committed
198

199
200
201
      /* Get a direct pointer on the part. */
      struct part *restrict p = &parts[i];
      struct xpart *restrict xp = &xparts[i];
Stefan Arridge's avatar
Stefan Arridge committed
202

203
      if (part_is_active(p, e)) {
204

205
206
        /* Let's cool ! */
        const double dt = get_timestep(p->time_bin, timeBase);
207
208
        cooling_cool_part(constants, us, cooling_func, p, xp, dt);
      }
Stefan Arridge's avatar
Stefan Arridge committed
209
210
211
212
213
214
    }
  }

  if (timer) TIMER_TOC(timer_do_cooling);
}

Pedro Gonnet's avatar
Pedro Gonnet committed
215
216
217
218
219
220
/**
 * @brief Sort the entries in ascending order using QuickSort.
 *
 * @param sort The entries
 * @param N The number of entries.
 */
221
void runner_do_sort_ascending(struct entry *sort, int N) {
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275

  struct {
    short int lo, hi;
  } qstack[10];
  int qpos, i, j, lo, hi, imin;
  struct entry temp;
  float pivot;

  /* Sort parts in cell_i in decreasing order with quicksort */
  qstack[0].lo = 0;
  qstack[0].hi = N - 1;
  qpos = 0;
  while (qpos >= 0) {
    lo = qstack[qpos].lo;
    hi = qstack[qpos].hi;
    qpos -= 1;
    if (hi - lo < 15) {
      for (i = lo; i < hi; i++) {
        imin = i;
        for (j = i + 1; j <= hi; j++)
          if (sort[j].d < sort[imin].d) imin = j;
        if (imin != i) {
          temp = sort[imin];
          sort[imin] = sort[i];
          sort[i] = temp;
        }
      }
    } else {
      pivot = sort[(lo + hi) / 2].d;
      i = lo;
      j = hi;
      while (i <= j) {
        while (sort[i].d < pivot) i++;
        while (sort[j].d > pivot) j--;
        if (i <= j) {
          if (i < j) {
            temp = sort[i];
            sort[i] = sort[j];
            sort[j] = temp;
          }
          i += 1;
          j -= 1;
        }
      }
      if (j > (lo + hi) / 2) {
        if (lo < j) {
          qpos += 1;
          qstack[qpos].lo = lo;
          qstack[qpos].hi = j;
        }
        if (i < hi) {
          qpos += 1;
          qstack[qpos].lo = i;
          qstack[qpos].hi = hi;
Pedro Gonnet's avatar
Pedro Gonnet committed
276
        }
277
278
279
280
281
282
283
284
285
286
287
288
      } else {
        if (i < hi) {
          qpos += 1;
          qstack[qpos].lo = i;
          qstack[qpos].hi = hi;
        }
        if (lo < j) {
          qpos += 1;
          qstack[qpos].lo = lo;
          qstack[qpos].hi = j;
        }
      }
Pedro Gonnet's avatar
Pedro Gonnet committed
289
    }
290
291
292
  }
}

Matthieu Schaller's avatar
Matthieu Schaller committed
293
294
295
296
297
298
299
300
/**
 * @brief Recursively checks that the flags are consistent in a cell hierarchy.
 *
 * Debugging function.
 *
 * @param c The #cell to check.
 * @param flags The sorting flags to check.
 */
301
void runner_check_sorts(struct cell *c, int flags) {
Matthieu Schaller's avatar
Matthieu Schaller committed
302
303

#ifdef SWIFT_DEBUG_CHECKS
Pedro Gonnet's avatar
Pedro Gonnet committed
304
  if (flags & ~c->sorted) error("Inconsistent sort flags (downward)!");
305
306
  if (c->split)
    for (int k = 0; k < 8; k++)
307
      if (c->progeny[k] != NULL && c->progeny[k]->count > 0)
308
        runner_check_sorts(c->progeny[k], c->sorted);
Matthieu Schaller's avatar
Matthieu Schaller committed
309
310
311
#else
  error("Calling debugging code without debugging flag activated.");
#endif
312
313
}

Pedro Gonnet's avatar
Pedro Gonnet committed
314
315
316
317
318
/**
 * @brief Sort the particles in the given cell along all cardinal directions.
 *
 * @param r The #runner.
 * @param c The #cell.
319
 * @param flags Cell flag.
320
321
 * @param cleanup If true, re-build the sorts for the selected flags instead
 *        of just adding them.
322
323
 * @param clock Flag indicating whether to record the timing or not, needed
 *      for recursive calls.
Pedro Gonnet's avatar
Pedro Gonnet committed
324
 */
325
326
void runner_do_sort(struct runner *r, struct cell *c, int flags, int cleanup,
                    int clock) {
327
328

  struct entry *fingers[8];
329
  const int count = c->count;
330
331
  const struct part *parts = c->parts;
  struct xpart *xparts = c->xparts;
Matthieu Schaller's avatar
Matthieu Schaller committed
332
  float buff[8];
333

334
335
  TIMER_TIC;

336
337
  /* We need to do the local sorts plus whatever was requested further up. */
  flags |= c->do_sort;
338
339
340
341
342
  if (cleanup) {
    c->sorted = 0;
  } else {
    flags &= ~c->sorted;
  }
343
  if (flags == 0 && !c->do_sub_sort) return;
344
345

  /* Check that the particles have been moved to the current time */
Pedro Gonnet's avatar
Pedro Gonnet committed
346
  if (flags && !cell_are_part_drifted(c, r->e))
347
    error("Sorting un-drifted cell c->nodeID=%d", c->nodeID);
Pedro Gonnet's avatar
Pedro Gonnet committed
348

349
350
351
352
353
#ifdef SWIFT_DEBUG_CHECKS
  /* Make sure the sort flags are consistent (downward). */
  runner_check_sorts(c, c->sorted);

  /* Make sure the sort flags are consistent (upard). */
Pedro Gonnet's avatar
Pedro Gonnet committed
354
355
356
  for (struct cell *finger = c->parent; finger != NULL;
       finger = finger->parent) {
    if (finger->sorted & ~c->sorted) error("Inconsistent sort flags (upward).");
357
  }
358

359
360
  /* Update the sort timer which represents the last time the sorts
     were re-set. */
361
  if (c->sorted == 0) c->ti_sort = r->e->ti_current;
362
#endif
363

364
365
366
367
368
369
370
  /* start by allocating the entry arrays in the requested dimensions. */
  for (int j = 0; j < 13; j++) {
    if ((flags & (1 << j)) && c->sort[j] == NULL) {
      if ((c->sort[j] = (struct entry *)malloc(sizeof(struct entry) *
                                               (count + 1))) == NULL)
        error("Failed to allocate sort memory.");
    }
371
372
373
374
375
376
  }

  /* Does this cell have any progeny? */
  if (c->split) {

    /* Fill in the gaps within the progeny. */
377
    float dx_max_sort = 0.0f;
378
    float dx_max_sort_old = 0.0f;
379
    for (int k = 0; k < 8; k++) {
380
      if (c->progeny[k] != NULL && c->progeny[k]->count > 0) {
381
382
383
384
385
        /* Only propagate cleanup if the progeny is stale. */
        runner_do_sort(r, c->progeny[k], flags,
                       cleanup && (c->progeny[k]->dx_max_sort >
                                   space_maxreldx * c->progeny[k]->dmin),
                       0);
386
        dx_max_sort = max(dx_max_sort, c->progeny[k]->dx_max_sort);
387
        dx_max_sort_old = max(dx_max_sort_old, c->progeny[k]->dx_max_sort_old);
388
      }
389
    }
390
    c->dx_max_sort = dx_max_sort;
391
    c->dx_max_sort_old = dx_max_sort_old;
392
393

    /* Loop over the 13 different sort arrays. */
394
    for (int j = 0; j < 13; j++) {
395
396
397
398
399

      /* Has this sort array been flagged? */
      if (!(flags & (1 << j))) continue;

      /* Init the particle index offsets. */
400
      int off[8];
401
402
      off[0] = 0;
      for (int k = 1; k < 8; k++)
403
404
405
406
407
408
        if (c->progeny[k - 1] != NULL)
          off[k] = off[k - 1] + c->progeny[k - 1]->count;
        else
          off[k] = off[k - 1];

      /* Init the entries and indices. */
409
      int inds[8];
410
      for (int k = 0; k < 8; k++) {
411
412
        inds[k] = k;
        if (c->progeny[k] != NULL && c->progeny[k]->count > 0) {
413
          fingers[k] = c->progeny[k]->sort[j];
414
415
416
417
418
419
420
          buff[k] = fingers[k]->d;
          off[k] = off[k];
        } else
          buff[k] = FLT_MAX;
      }

      /* Sort the buffer. */
421
422
      for (int i = 0; i < 7; i++)
        for (int k = i + 1; k < 8; k++)
423
          if (buff[inds[k]] < buff[inds[i]]) {
424
            int temp_i = inds[i];
425
426
427
428
429
            inds[i] = inds[k];
            inds[k] = temp_i;
          }

      /* For each entry in the new sort list. */
430
      struct entry *finger = c->sort[j];
431
      for (int ind = 0; ind < count; ind++) {
432
433
434
435
436
437
438
439
440
441

        /* Copy the minimum into the new sort array. */
        finger[ind].d = buff[inds[0]];
        finger[ind].i = fingers[inds[0]]->i + off[inds[0]];

        /* Update the buffer. */
        fingers[inds[0]] += 1;
        buff[inds[0]] = fingers[inds[0]]->d;

        /* Find the smallest entry. */
442
        for (int k = 1; k < 8 && buff[inds[k]] < buff[inds[k - 1]]; k++) {
443
          int temp_i = inds[k - 1];
444
445
          inds[k - 1] = inds[k];
          inds[k] = temp_i;
Pedro Gonnet's avatar
Pedro Gonnet committed
446
        }
447

448
449
450
      } /* Merge. */

      /* Add a sentinel. */
451
452
      c->sort[j][count].d = FLT_MAX;
      c->sort[j][count].i = 0;
453
454

      /* Mark as sorted. */
455
      atomic_or(&c->sorted, 1 << j);
456
457
458
459
460
461
462
463

    } /* loop over sort arrays. */

  } /* progeny? */

  /* Otherwise, just sort. */
  else {

464
    /* Reset the sort distance */
465
    if (c->sorted == 0) {
466
467
#ifdef SWIFT_DEBUG_CHECKS
      if (xparts != NULL && c->nodeID != engine_rank)
468
        error("Have non-NULL xparts in foreign cell");
469
#endif
470
471
472
473
474
475
476
477

      /* And the individual sort distances if we are a local cell */
      if (xparts != NULL) {
        for (int k = 0; k < count; k++) {
          xparts[k].x_diff_sort[0] = 0.0f;
          xparts[k].x_diff_sort[1] = 0.0f;
          xparts[k].x_diff_sort[2] = 0.0f;
        }
478
      }
479
480
      c->dx_max_sort_old = 0.f;
      c->dx_max_sort = 0.f;
481
482
    }

483
    /* Fill the sort array. */
484
    for (int k = 0; k < count; k++) {
485
      const double px[3] = {parts[k].x[0], parts[k].x[1], parts[k].x[2]};
486
      for (int j = 0; j < 13; j++)
487
        if (flags & (1 << j)) {
488
489
490
491
          c->sort[j][k].i = k;
          c->sort[j][k].d = px[0] * runner_shift[j][0] +
                            px[1] * runner_shift[j][1] +
                            px[2] * runner_shift[j][2];
492
        }
493
    }
494
495

    /* Add the sentinel and sort. */
496
    for (int j = 0; j < 13; j++)
497
      if (flags & (1 << j)) {
498
499
500
        c->sort[j][count].d = FLT_MAX;
        c->sort[j][count].i = 0;
        runner_do_sort_ascending(c->sort[j], count);
501
        atomic_or(&c->sorted, 1 << j);
502
503
504
      }
  }

505
#ifdef SWIFT_DEBUG_CHECKS
Matthieu Schaller's avatar
Matthieu Schaller committed
506
  /* Verify the sorting. */
507
  for (int j = 0; j < 13; j++) {
508
    if (!(flags & (1 << j))) continue;
509
    struct entry *finger = c->sort[j];
510
    for (int k = 1; k < count; k++) {
511
512
513
514
515
      if (finger[k].d < finger[k - 1].d)
        error("Sorting failed, ascending array.");
      if (finger[k].i >= count) error("Sorting failed, indices borked.");
    }
  }
Pedro Gonnet's avatar
Pedro Gonnet committed
516

517
518
519
520
  /* Make sure the sort flags are consistent (downward). */
  runner_check_sorts(c, flags);

  /* Make sure the sort flags are consistent (upward). */
Pedro Gonnet's avatar
Pedro Gonnet committed
521
522
523
  for (struct cell *finger = c->parent; finger != NULL;
       finger = finger->parent) {
    if (finger->sorted & ~c->sorted) error("Inconsistent sort flags.");
524
  }
525
#endif
526

527
528
529
530
531
  /* Clear the cell's sort flags. */
  c->do_sort = 0;
  c->do_sub_sort = 0;
  c->requires_sorts = 0;

532
533
534
  if (clock) TIMER_TOC(timer_dosort);
}

535
/**
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
 * @brief Initialize the multipoles before the gravity calculation.
 *
 * @param r The runner thread.
 * @param c The cell.
 * @param timer 1 if the time is to be recorded.
 */
void runner_do_init_grav(struct runner *r, struct cell *c, int timer) {

  const struct engine *e = r->e;

  TIMER_TIC;

#ifdef SWIFT_DEBUG_CHECKS
  if (!(e->policy & engine_policy_self_gravity))
    error("Grav-init task called outside of self-gravity calculation");
#endif

  /* Anything to do here? */
554
  if (!cell_is_active_gravity(c, e)) return;
555
556

  /* Reset the gravity acceleration tensors */
557
  gravity_field_tensors_init(&c->multipole->pot, e->ti_current);
558
559
560
561
562
563
564
565
566
567
568

  /* Recurse? */
  if (c->split) {
    for (int k = 0; k < 8; k++) {
      if (c->progeny[k] != NULL) runner_do_init_grav(r, c->progeny[k], 0);
    }
  }

  if (timer) TIMER_TOC(timer_init_grav);
}

569
/**
570
571
572
573
574
 * @brief Intermediate task after the gradient loop that does final operations
 * on the gradient quantities and optionally slope limits the gradients
 *
 * @param r The runner thread.
 * @param c The cell.
575
 * @param timer Are we timing this ?
576
 */
577
void runner_do_extra_ghost(struct runner *r, struct cell *c, int timer) {
578

579
#ifdef EXTRA_HYDRO_LOOP
580

581
582
  struct part *restrict parts = c->parts;
  const int count = c->count;
583
  const struct engine *e = r->e;
584

585
586
  TIMER_TIC;

587
  /* Anything to do here? */
588
  if (!cell_is_active_hydro(c, e)) return;
589

590
591
592
  /* Recurse? */
  if (c->split) {
    for (int k = 0; k < 8; k++)
593
      if (c->progeny[k] != NULL) runner_do_extra_ghost(r, c->progeny[k], 0);
594
595
596
597
598
599
600
601
  } else {

    /* Loop over the parts in this cell. */
    for (int i = 0; i < count; i++) {

      /* Get a direct pointer on the part. */
      struct part *restrict p = &parts[i];

602
      if (part_is_active(p, e)) {
603
604
605
606
607
608

        /* Get ready for a force calculation */
        hydro_end_gradient(p);
      }
    }
  }
609

610
611
  if (timer) TIMER_TOC(timer_do_extra_ghost);

612
613
#else
  error("SWIFT was not compiled with the extra hydro loop activated.");
614
#endif
615
}
616

617
/**
618
619
 * @brief Intermediate task after the density to check that the smoothing
 * lengths are correct.
620
 *
Pedro Gonnet's avatar
Pedro Gonnet committed
621
 * @param r The runner thread.
622
 * @param c The cell.
623
 * @param timer Are we timing this ?
624
 */
625
void runner_do_ghost(struct runner *r, struct cell *c, int timer) {
626

Matthieu Schaller's avatar
Matthieu Schaller committed
627
628
  struct part *restrict parts = c->parts;
  struct xpart *restrict xparts = c->xparts;
629
  const struct engine *e = r->e;
630
  const struct space *s = e->s;
631
  const float hydro_h_max = e->hydro_properties->h_max;
632
633
634
  const float eps = e->hydro_properties->h_tolerance;
  const float hydro_eta_dim =
      pow_dimension(e->hydro_properties->eta_neighbours);
635
  const int max_smoothing_iter = e->hydro_properties->max_smoothing_iterations;
636
  int redo = 0, count = 0;
637

638
639
  TIMER_TIC;

640
  /* Anything to do here? */
641
  if (!cell_is_active_hydro(c, e)) return;
642

643
644
  /* Recurse? */
  if (c->split) {
Matthieu Schaller's avatar
Matthieu Schaller committed
645
    for (int k = 0; k < 8; k++)
646
647
      if (c->progeny[k] != NULL) runner_do_ghost(r, c->progeny[k], 0);
  } else {
648

649
    /* Init the list of active particles that have to be updated. */
650
    int *pid = NULL;
651
    if ((pid = malloc(sizeof(int) * c->count)) == NULL)
652
      error("Can't allocate memory for pid.");
653
654
655
656
657
    for (int k = 0; k < c->count; k++)
      if (part_is_active(&parts[k], e)) {
        pid[count] = k;
        ++count;
      }
658

659
660
661
    /* While there are particles that need to be updated... */
    for (int num_reruns = 0; count > 0 && num_reruns < max_smoothing_iter;
         num_reruns++) {
662

663
664
      /* Reset the redo-count. */
      redo = 0;
665

666
      /* Loop over the remaining active parts in this cell. */
667
      for (int i = 0; i < count; i++) {
668

669
        /* Get a direct pointer on the part. */
670
671
        struct part *p = &parts[pid[i]];
        struct xpart *xp = &xparts[pid[i]];
672

673
#ifdef SWIFT_DEBUG_CHECKS
674
        /* Is this part within the timestep? */
675
676
677
        if (!part_is_active(p, e)) error("Ghost applied to inactive particle");
#endif

678
679
680
681
682
        /* Get some useful values */
        const float h_old = p->h;
        const float h_old_dim = pow_dimension(h_old);
        const float h_old_dim_minus_one = pow_dimension_minus_one(h_old);
        float h_new;
683

684
        if (p->density.wcount == 0.f) { /* No neighbours case */
685

686
687
688
          /* Double h and try again */
          h_new = 2.f * h_old;
        } else {
Matthieu Schaller's avatar
Matthieu Schaller committed
689

690
691
          /* Finish the density calculation */
          hydro_end_density(p);
692

693
694
695
696
697
698
699
          /* Compute one step of the Newton-Raphson scheme */
          const float n_sum = p->density.wcount * h_old_dim;
          const float n_target = hydro_eta_dim;
          const float f = n_sum - n_target;
          const float f_prime =
              p->density.wcount_dh * h_old_dim +
              hydro_dimension * p->density.wcount * h_old_dim_minus_one;
700

701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
          h_new = h_old - f / f_prime;

#ifdef SWIFT_DEBUG_CHECKS
          if ((f > 0.f && h_new > h_old) || (f < 0.f && h_new < h_old))
            error(
                "Smoothing length correction not going in the right direction");
#endif

          /* Safety check: truncate to the range [ h_old/2 , 2h_old ]. */
          h_new = min(h_new, 2.f * h_old);
          h_new = max(h_new, 0.5f * h_old);
        }

        /* Check whether the particle has an inappropriate smoothing length */
        if (fabsf(h_new - h_old) > eps * h_old) {
716

717
          /* Ok, correct then */
718
          p->h = h_new;
719

720
721
          /* If below the absolute maximum, try again */
          if (p->h < hydro_h_max) {
722

723
724
725
            /* Flag for another round of fun */
            pid[redo] = pid[i];
            redo += 1;
726

727
            /* Re-initialise everything */
728
            hydro_init_part(p, &s->hs);
729
730
731
732
733
734
735

            /* Off we go ! */
            continue;
          } else {

            /* Ok, this particle is a lost cause... */
            p->h = hydro_h_max;
736
737
738
739

            /* Do some damage control if no neighbours at all were found */
            if (p->density.wcount == kernel_root * kernel_norm)
              hydro_part_has_no_neighbours(p, xp);
740
          }
741
        }
742

743
        /* We now have a particle whose smoothing length has converged */
Matthieu Schaller's avatar
Matthieu Schaller committed
744

745
        /* As of here, particle force variables will be set. */
746

747
748
        /* Compute variables required for the force loop */
        hydro_prepare_force(p, xp);
749

750
751
        /* The particle force values are now set.  Do _NOT_
           try to read any particle density variables! */
Matthieu Schaller's avatar
Matthieu Schaller committed
752

753
754
        /* Prepare the particle for the force loop over neighbours */
        hydro_reset_acceleration(p);
755
756
      }

757
758
      /* We now need to treat the particles whose smoothing length had not
       * converged again */
759

760
761
762
      /* Re-set the counter for the next loop (potentially). */
      count = redo;
      if (count > 0) {
763

764
765
        /* Climb up the cell hierarchy. */
        for (struct cell *finger = c; finger != NULL; finger = finger->parent) {
Matthieu Schaller's avatar
Matthieu Schaller committed
766

767
768
          /* Run through this cell's density interactions. */
          for (struct link *l = finger->density; l != NULL; l = l->next) {
Matthieu Schaller's avatar
Matthieu Schaller committed
769

770
771
772
773
#ifdef SWIFT_DEBUG_CHECKS
            if (l->t->ti_run < r->e->ti_current)
              error("Density task should have been run.");
#endif
Matthieu Schaller's avatar
Matthieu Schaller committed
774

775
776
            /* Self-interaction? */
            if (l->t->type == task_type_self)
777
              runner_doself_subset_branch_density(r, finger, parts, pid, count);
Matthieu Schaller's avatar
Matthieu Schaller committed
778

779
780
            /* Otherwise, pair interaction? */
            else if (l->t->type == task_type_pair) {
781

782
783
              /* Left or right? */
              if (l->t->ci == finger)
James Willis's avatar
James Willis committed
784
785
                runner_dopair_subset_branch_density(r, finger, parts, pid,
                                                    count, l->t->cj);
786
              else
James Willis's avatar
James Willis committed
787
788
                runner_dopair_subset_branch_density(r, finger, parts, pid,
                                                    count, l->t->ci);
789
            }
790

791
792
793
794
            /* Otherwise, sub-self interaction? */
            else if (l->t->type == task_type_sub_self)
              runner_dosub_subset_density(r, finger, parts, pid, count, NULL,
                                          -1, 1);
795

796
797
798
799
800
801
802
803
804
805
806
            /* Otherwise, sub-pair interaction? */
            else if (l->t->type == task_type_sub_pair) {

              /* Left or right? */
              if (l->t->ci == finger)
                runner_dosub_subset_density(r, finger, parts, pid, count,
                                            l->t->cj, -1, 1);
              else
                runner_dosub_subset_density(r, finger, parts, pid, count,
                                            l->t->ci, -1, 1);
            }
807
808
809
          }
        }
      }
810
    }
811

812
813
#ifdef SWIFT_DEBUG_CHECKS
    if (count) {
814
      error("Smoothing length failed to converge on %i particles.", count);
815
816
    }
#else
817
    if (count)
818
      error("Smoothing length failed to converge on %i particles.", count);
819
#endif
820

821
822
823
    /* Be clean */
    free(pid);
  }
824

825
  if (timer) TIMER_TOC(timer_do_ghost);
826
827
}

828
/**
829
 * @brief Unskip any hydro tasks associated with active cells.
830
831
 *
 * @param c The cell.
832
 * @param e The engine.
833
 */
834
static void runner_do_unskip_hydro(struct cell *c, struct engine *e) {
835

836
  /* Ignore empty cells. */
837
  if (c->count == 0) return;
838

839
  /* Skip inactive cells. */
840
  if (!cell_is_active_hydro(c, e)) return;
841

842
  /* Recurse */
843
844
  if (c->split) {
    for (int k = 0; k < 8; k++) {
Matthieu Schaller's avatar
Matthieu Schaller committed
845
      if (c->progeny[k] != NULL) {
Matthieu Schaller's avatar
Matthieu Schaller committed
846
        struct cell *cp = c->progeny[k];
847
        runner_do_unskip_hydro(cp, e);
848
849
850
      }
    }
  }
851
852

  /* Unskip any active tasks. */
853
  const int forcerebuild = cell_unskip_hydro_tasks(c, &e->sched);
854
  if (forcerebuild) atomic_inc(&e->forcerebuild);
855
}
856

857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
/**
 * @brief Unskip any gravity tasks associated with active cells.
 *
 * @param c The cell.
 * @param e The engine.
 */
static void runner_do_unskip_gravity(struct cell *c, struct engine *e) {

  /* Ignore empty cells. */
  if (c->gcount == 0) return;

  /* Skip inactive cells. */
  if (!cell_is_active_gravity(c, e)) return;

  /* Recurse */
  if (c->split) {
    for (int k = 0; k < 8; k++) {
      if (c->progeny[k] != NULL) {
        struct cell *cp = c->progeny[k];
        runner_do_unskip_gravity(cp, e);
      }
    }
  }

  /* Unskip any active tasks. */
  cell_unskip_gravity_tasks(c, &e->sched);
}

885
/**
886
 * @brief Mapper function to unskip active tasks.
887
888
889
890
891
 *
 * @param map_data An array of #cell%s.
 * @param num_elements Chunk size.
 * @param extra_data Pointer to an #engine.
 */
892
893
void runner_do_unskip_mapper(void *map_data, int num_elements,
                             void *extra_data) {
894

895
  struct engine *e = (struct engine *)extra_data;
896
897
  struct space *s = e->s;
  int *local_cells = (int *)map_data;
Matthieu Schaller's avatar
Matthieu Schaller committed
898

899
  for (int ind = 0; ind < num_elements; ind++) {
900
    struct cell *c = &s->cells_top[local_cells[ind]];
901
    if (c != NULL) {
902
903
904
905
      if (e->policy & engine_policy_hydro) runner_do_unskip_hydro(c, e);
      if (e->policy &
          (engine_policy_self_gravity | engine_policy_external_gravity))
        runner_do_unskip_gravity(c, e);
906
    }
907
  }
908
}
909
/**
910
 * @brief Drift all part in a cell.
Matthieu Schaller's avatar