runner.c 38.9 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
8
 * 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.
9
 *
10
11
12
13
 * 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.
14
 *
15
16
 * 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/>.
17
 *
18
 ******************************************************************************/
Pedro Gonnet's avatar
Pedro Gonnet committed
19

Pedro Gonnet's avatar
Pedro Gonnet committed
20
21
/* Config parameters. */
#include "../config.h"
Pedro Gonnet's avatar
Pedro Gonnet committed
22
23
24
25

/* Some standard headers. */
#include <float.h>
#include <limits.h>
26
#include <stdlib.h>
Pedro Gonnet's avatar
Pedro Gonnet committed
27

28
29
/* MPI headers. */
#ifdef WITH_MPI
30
#include <mpi.h>
31
32
#endif

33
34
35
/* This object's header. */
#include "runner.h"

Pedro Gonnet's avatar
Pedro Gonnet committed
36
/* Local headers. */
Matthieu Schaller's avatar
Matthieu Schaller committed
37
#include "approx_math.h"
38
#include "atomic.h"
39
#include "const.h"
40
#include "debug.h"
Pedro Gonnet's avatar
Pedro Gonnet committed
41
#include "engine.h"
42
#include "error.h"
43
44
45
#include "gravity.h"
#include "hydro.h"
#include "minmax.h"
46
47
48
49
#include "scheduler.h"
#include "space.h"
#include "task.h"
#include "timers.h"
Pedro Gonnet's avatar
Pedro Gonnet committed
50

51
/* Orientation of the cell pairs */
52
53
54
55
56
57
58
59
60
61
62
63
64
65
const float runner_shift[13 * 3] = {
    5.773502691896258e-01, 5.773502691896258e-01,  5.773502691896258e-01,
    7.071067811865475e-01, 7.071067811865475e-01,  0.0,
    5.773502691896258e-01, 5.773502691896258e-01,  -5.773502691896258e-01,
    7.071067811865475e-01, 0.0,                    7.071067811865475e-01,
    1.0,                   0.0,                    0.0,
    7.071067811865475e-01, 0.0,                    -7.071067811865475e-01,
    5.773502691896258e-01, -5.773502691896258e-01, 5.773502691896258e-01,
    7.071067811865475e-01, -7.071067811865475e-01, 0.0,
    5.773502691896258e-01, -5.773502691896258e-01, -5.773502691896258e-01,
    0.0,                   7.071067811865475e-01,  7.071067811865475e-01,
    0.0,                   1.0,                    0.0,
    0.0,                   7.071067811865475e-01,  -7.071067811865475e-01,
    0.0,                   0.0,                    1.0, };
66
67

/* Does the axis need flipping ? */
68
69
const char runner_flip[27] = {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0,
                              0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
Tom Theuns's avatar
Tom Theuns committed
70
#define MY_CELL 428428428
Matthieu Schaller's avatar
Matthieu Schaller committed
71
72
73
74
75
76
77
78
79
#define DX 0.1
#define NX 1000
#define CELL_ID                                                  \
  ((int)(c->loc[0] / DX) * NX *NX + (int)(c->loc[1] / DX) * NX + \
   (int)(c->loc[2] / DX))
#define OUT                                                                    \
  if (CELL_ID == MY_CELL) {                                                    \
    message(" cell= %d gcount=%d time=%f \n", CELL_ID, c->gcount, r->e->time); \
  }
Tom Theuns's avatar
Tom Theuns committed
80
//#define OUT  message(" cell %d %d %f \n",CELL_ID, c->count, r->e->time);
Matthieu Schaller's avatar
Matthieu Schaller committed
81
82
//#define OUT  if(CELL_ID == MY_CELL) message("\n cell %f %f %f %d %d
//%f\n",c->loc[0],c->loc[1],c->loc[2], CELL_ID, c->count, r->e->time);
Tom Theuns's avatar
Tom Theuns committed
83

84
/* Import the density loop functions. */
85
86
87
#define FUNCTION density
#include "runner_doiact.h"

88
/* Import the force loop functions. */
89
90
91
92
#undef FUNCTION
#define FUNCTION force
#include "runner_doiact.h"

93
94
95
/* Import the gravity loop functions. */
#include "runner_doiact_grav.h"

Tom Theuns's avatar
Tom Theuns committed
96
97
98
99
100
101
102
103
/**
 * @brief Calculate gravity acceleration from external potential
 *
 * @param runner task
 * @param cell
 */
void runner_dograv_external(struct runner *r, struct cell *c) {

104
  struct gpart *g, *gparts = c->gparts;
Tom Theuns's avatar
Tom Theuns committed
105
  float L[3], E;
106
107
  int i, k, gcount = c->gcount;
  const int ti_current = r->e->ti_current;
Matthieu Schaller's avatar
Matthieu Schaller committed
108
109
110

  // struct space *s = r->e->s;
  // double CentreOfPotential[3];
111
  TIMER_TIC;
Tom Theuns's avatar
Tom Theuns committed
112

Matthieu Schaller's avatar
Matthieu Schaller committed
113
114
  /* 	 /\* location of external gravity point mass - should pass in as
   * paraneter *\/ */
Tom Theuns's avatar
Tom Theuns committed
115
116
117
118
  /* CentreOfPotential[0] = 0.5 * s->dim[0]; */
  /* CentreOfPotential[1] = 0.5 * s->dim[1]; */
  /* CentreOfPotential[2] = 0.5 * s->dim[2]; */

Matthieu Schaller's avatar
Matthieu Schaller committed
119
120
121
  message(" (x,y,z) = (%e, %e, %e), M= %e", r->e->potential->point_mass.x,
          r->e->potential->point_mass.y, r->e->potential->point_mass.z,
          r->e->potential->point_mass.mass);
122
123
  exit(-1);

Tom Theuns's avatar
Tom Theuns committed
124
125
126
127
128
129
130
131
  /* Recurse? */
  if (c->split) {
    for (k = 0; k < 8; k++)
      if (c->progeny[k] != NULL) runner_dograv_external(r, c->progeny[k]);
    return;
  }

#ifdef TASK_VERBOSE
Matthieu Schaller's avatar
Matthieu Schaller committed
132
  OUT;
Tom Theuns's avatar
Tom Theuns committed
133
#endif
134
  /* Loop over the parts in this cell. */
135
  for (i = 0; i < gcount; i++) {
136

137
138
139
140
141
    /* Get a direct pointer on the part. */
    g = &gparts[i];

    /* Is this part within the time step? */
    if (g->ti_end <= ti_current) {
Matthieu Schaller's avatar
Matthieu Schaller committed
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
      //		external_gravity_pointmass(e->physical_constants,
      // potential_constants, g);
      external_gravity_pointmass(r->e->physical_constants, g);

      /* check for energy and angular momentum conservation - begin by
       * synchronizing velocity*/
      const float dx = g->x[0] - External_Potential_X;
      const float dy = g->x[1] - External_Potential_Y;
      const float dz = g->x[2] - External_Potential_Z;
      const float dr = sqrtf((dx * dx) + (dy * dy) + (dz * dz));
      const float rinv = 1.f / sqrtf(dx * dx + dy * dy + dz * dz);

      /* /\* current acceleration *\/ */
      /* g->a_grav[0] = - const_G *  External_Potential_Mass * dx * rinv * rinv
       * * rinv; */
      /* g->a_grav[1] = - const_G *  External_Potential_Mass * dy * rinv * rinv
       * * rinv; */
      /* g->a_grav[2] = - const_G *  External_Potential_Mass * dz * rinv * rinv
       * * rinv; */

      const int current_dti = g->ti_end - g->ti_begin;
      const float dt = 0.5f * current_dti * r->e->timeBase;
      const float vx = g->v_full[0] + dt * g->a_grav[0];
      const float vy = g->v_full[1] + dt * g->a_grav[1];
      const float vz = g->v_full[2] + dt * g->a_grav[2];

      /* E/L */
      E = 0.5 * ((vx * vx) + (vy * vy) + (vz * vz)) -
          const_G * External_Potential_Mass * rinv;
171
172
173
      L[0] = dy * vz - dz * vy;
      L[1] = dz * vx - dx * vz;
      L[2] = dx * vy - dy * vx;
Matthieu Schaller's avatar
Matthieu Schaller committed
174
175
176
177
178
179
180
181
182
183
184
185
      if (abs(g->id) == 1) {
        float v2 = vx * vx + vy * vy + vz * vz;
        float fg = const_G * External_Potential_Mass * rinv;
        float fga = sqrtf((g->a_grav[0] * g->a_grav[0]) +
                          (g->a_grav[1] * g->a_grav[1]) +
                          (g->a_grav[2] * g->a_grav[2])) *
                    dr;
        // message("grav_external time= %f\t V_c^2= %f GM/r= %f E= %f L[2]= %f
        // x= %f y= %f vx= %f vy= %f\n", r->e->time, v2, fg, E, L[2], g->x[0],
        // g->x[1], vx, vy);
        message("%f\t %f %f %f %f %f %f %f %f %f %f %f %f\n", r->e->time, g->tx,
                g->tv, dt, v2, fg, fga, E, L[2], g->x[0], g->x[1], vx, vy);
186
187
188
        // message(" G=%e M=%e\n", const_G, External_Potential_Mass);
      }
    }
189
190
  }
  TIMER_TOC(timer_dograv_external);
Tom Theuns's avatar
Tom Theuns committed
191
192
}

Pedro Gonnet's avatar
Pedro Gonnet committed
193
194
195
196
197
198
/**
 * @brief Sort the entries in ascending order using QuickSort.
 *
 * @param sort The entries
 * @param N The number of entries.
 */
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
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

void runner_dosort_ascending(struct entry *sort, int N) {

  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
255
        }
256
257
258
259
260
261
262
263
264
265
266
267
      } 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
268
    }
269
270
271
  }
}

Pedro Gonnet's avatar
Pedro Gonnet committed
272
273
274
275
276
/**
 * @brief Sort the particles in the given cell along all cardinal directions.
 *
 * @param r The #runner.
 * @param c The #cell.
277
 * @param flags Cell flag.
278
279
 * @param clock Flag indicating whether to record the timing or not, needed
 *      for recursive calls.
Pedro Gonnet's avatar
Pedro Gonnet committed
280
 */
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368

void runner_dosort(struct runner *r, struct cell *c, int flags, int clock) {

  struct entry *finger;
  struct entry *fingers[8];
  struct part *parts = c->parts;
  struct entry *sort;
  int j, k, count = c->count;
  int i, ind, off[8], inds[8], temp_i, missing;
  // float shift[3];
  float buff[8], px[3];

  TIMER_TIC

  /* Clean-up the flags, i.e. filter out what's already been sorted. */
  flags &= ~c->sorted;
  if (flags == 0) return;

  /* start by allocating the entry arrays. */
  if (c->sort == NULL || c->sortsize < count) {
    if (c->sort != NULL) free(c->sort);
    c->sortsize = count * 1.1;
    if ((c->sort = (struct entry *)malloc(sizeof(struct entry) *
                                          (c->sortsize + 1) * 13)) == NULL)
      error("Failed to allocate sort memory.");
  }
  sort = c->sort;

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

    /* Fill in the gaps within the progeny. */
    for (k = 0; k < 8; k++) {
      if (c->progeny[k] == NULL) continue;
      missing = flags & ~c->progeny[k]->sorted;
      if (missing) runner_dosort(r, c->progeny[k], missing, 0);
    }

    /* Loop over the 13 different sort arrays. */
    for (j = 0; j < 13; j++) {

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

      /* Init the particle index offsets. */
      for (off[0] = 0, k = 1; k < 8; k++)
        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. */
      for (k = 0; k < 8; k++) {
        inds[k] = k;
        if (c->progeny[k] != NULL && c->progeny[k]->count > 0) {
          fingers[k] = &c->progeny[k]->sort[j * (c->progeny[k]->count + 1)];
          buff[k] = fingers[k]->d;
          off[k] = off[k];
        } else
          buff[k] = FLT_MAX;
      }

      /* Sort the buffer. */
      for (i = 0; i < 7; i++)
        for (k = i + 1; k < 8; k++)
          if (buff[inds[k]] < buff[inds[i]]) {
            temp_i = inds[i];
            inds[i] = inds[k];
            inds[k] = temp_i;
          }

      /* For each entry in the new sort list. */
      finger = &sort[j * (count + 1)];
      for (ind = 0; ind < count; ind++) {

        /* 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. */
        for (k = 1; k < 8 && buff[inds[k]] < buff[inds[k - 1]]; k++) {
          temp_i = inds[k - 1];
          inds[k - 1] = inds[k];
          inds[k] = temp_i;
Pedro Gonnet's avatar
Pedro Gonnet committed
369
        }
370

371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
      } /* Merge. */

      /* Add a sentinel. */
      sort[j * (count + 1) + count].d = FLT_MAX;
      sort[j * (count + 1) + count].i = 0;

      /* Mark as sorted. */
      c->sorted |= (1 << j);

    } /* loop over sort arrays. */

  } /* progeny? */

  /* Otherwise, just sort. */
  else {

    /* Fill the sort array. */
    for (k = 0; k < count; k++) {
      px[0] = parts[k].x[0];
      px[1] = parts[k].x[1];
      px[2] = parts[k].x[2];
      for (j = 0; j < 13; j++)
        if (flags & (1 << j)) {
          sort[j * (count + 1) + k].i = k;
          sort[j * (count + 1) + k].d = px[0] * runner_shift[3 * j + 0] +
                                        px[1] * runner_shift[3 * j + 1] +
                                        px[2] * runner_shift[3 * j + 2];
        }
399
    }
400
401
402
403
404
405
406
407
408
409
410

    /* Add the sentinel and sort. */
    for (j = 0; j < 13; j++)
      if (flags & (1 << j)) {
        sort[j * (count + 1) + count].d = FLT_MAX;
        sort[j * (count + 1) + count].i = 0;
        runner_dosort_ascending(&sort[j * (count + 1)], count);
        c->sorted |= (1 << j);
      }
  }

Matthieu Schaller's avatar
Matthieu Schaller committed
411
412
413
414
415
416
417
418
419
420
421
422
  /* Verify the sorting. */
  /* for ( j = 0 ; j < 13 ; j++ ) {
      if ( !( flags & (1 << j) ) )
          continue;
      finger = &sort[ j*(count + 1) ];
      for ( k = 1 ; k < count ; k++ ) {
          if ( finger[k].d < finger[k-1].d )
              error( "Sorting failed, ascending array." );
          if ( finger[k].i >= count )
              error( "Sorting failed, indices borked." );
          }
      } */
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513

  if (clock) TIMER_TOC(timer_dosort);
}

void runner_dogsort(struct runner *r, struct cell *c, int flags, int clock) {

  struct entry *finger;
  struct entry *fingers[8];
  struct gpart *gparts = c->gparts;
  struct entry *gsort;
  int j, k, count = c->gcount;
  int i, ind, off[8], inds[8], temp_i, missing;
  // float shift[3];
  float buff[8], px[3];

  TIMER_TIC

  /* Clean-up the flags, i.e. filter out what's already been sorted. */
  flags &= ~c->gsorted;
  if (flags == 0) return;

  /* start by allocating the entry arrays. */
  if (c->gsort == NULL || c->gsortsize < count) {
    if (c->gsort != NULL) free(c->gsort);
    c->gsortsize = count * 1.1;
    if ((c->gsort = (struct entry *)malloc(sizeof(struct entry) *
                                           (c->gsortsize + 1) * 13)) == NULL)
      error("Failed to allocate sort memory.");
  }
  gsort = c->gsort;

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

    /* Fill in the gaps within the progeny. */
    for (k = 0; k < 8; k++) {
      if (c->progeny[k] == NULL) continue;
      missing = flags & ~c->progeny[k]->gsorted;
      if (missing) runner_dogsort(r, c->progeny[k], missing, 0);
    }

    /* Loop over the 13 different sort arrays. */
    for (j = 0; j < 13; j++) {

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

      /* Init the particle index offsets. */
      for (off[0] = 0, k = 1; k < 8; k++)
        if (c->progeny[k - 1] != NULL)
          off[k] = off[k - 1] + c->progeny[k - 1]->gcount;
        else
          off[k] = off[k - 1];

      /* Init the entries and indices. */
      for (k = 0; k < 8; k++) {
        inds[k] = k;
        if (c->progeny[k] != NULL && c->progeny[k]->gcount > 0) {
          fingers[k] = &c->progeny[k]->gsort[j * (c->progeny[k]->gcount + 1)];
          buff[k] = fingers[k]->d;
          off[k] = off[k];
        } else
          buff[k] = FLT_MAX;
      }

      /* Sort the buffer. */
      for (i = 0; i < 7; i++)
        for (k = i + 1; k < 8; k++)
          if (buff[inds[k]] < buff[inds[i]]) {
            temp_i = inds[i];
            inds[i] = inds[k];
            inds[k] = temp_i;
          }

      /* For each entry in the new sort list. */
      finger = &gsort[j * (count + 1)];
      for (ind = 0; ind < count; ind++) {

        /* 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. */
        for (k = 1; k < 8 && buff[inds[k]] < buff[inds[k - 1]]; k++) {
          temp_i = inds[k - 1];
          inds[k - 1] = inds[k];
          inds[k] = temp_i;
514
        }
Pedro Gonnet's avatar
Pedro Gonnet committed
515

516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
      } /* Merge. */

      /* Add a sentinel. */
      gsort[j * (count + 1) + count].d = FLT_MAX;
      gsort[j * (count + 1) + count].i = 0;

      /* Mark as sorted. */
      c->gsorted |= (1 << j);

    } /* loop over sort arrays. */

  } /* progeny? */

  /* Otherwise, just sort. */
  else {

    /* Fill the sort array. */
    for (k = 0; k < count; k++) {
      px[0] = gparts[k].x[0];
      px[1] = gparts[k].x[1];
      px[2] = gparts[k].x[2];
      for (j = 0; j < 13; j++)
        if (flags & (1 << j)) {
          gsort[j * (count + 1) + k].i = k;
          gsort[j * (count + 1) + k].d = px[0] * runner_shift[3 * j + 0] +
                                         px[1] * runner_shift[3 * j + 1] +
                                         px[2] * runner_shift[3 * j + 2];
        }
Pedro Gonnet's avatar
Pedro Gonnet committed
544
    }
545
546
547
548
549
550
551
552
553
554
555

    /* Add the sentinel and sort. */
    for (j = 0; j < 13; j++)
      if (flags & (1 << j)) {
        gsort[j * (count + 1) + count].d = FLT_MAX;
        gsort[j * (count + 1) + count].i = 0;
        runner_dosort_ascending(&gsort[j * (count + 1)], count);
        c->gsorted |= (1 << j);
      }
  }

Matthieu Schaller's avatar
Matthieu Schaller committed
556
557
558
559
560
561
562
563
564
565
566
567
  /* Verify the sorting. */
  /* for ( j = 0 ; j < 13 ; j++ ) {
      if ( !( flags & (1 << j) ) )
          continue;
      finger = &c->gsort[ j*(count + 1) ];
      for ( k = 1 ; k < count ; k++ ) {
          if ( finger[k].d < finger[k-1].d )
              error( "Sorting failed, ascending array." );
          if ( finger[k].i < 0 || finger[k].i >= count )
              error( "Sorting failed, indices borked." );
          }
      } */
568
569
570
571

  if (clock) TIMER_TOC(timer_dosort);
}

572
573
574
575
576
/**
 * @brief Initialize the particles before the density calculation
 *
 * @param r The runner thread.
 * @param c The cell.
Matthieu Schaller's avatar
Matthieu Schaller committed
577
 * @param timer 1 if the time is to be recorded.
578
579
 */

580
void runner_doinit(struct runner *r, struct cell *c, int timer) {
581

582
583
  struct part *const parts = c->parts;
  struct gpart *const gparts = c->gparts;
Matthieu Schaller's avatar
Matthieu Schaller committed
584
  const int count = c->count;
585
  const int gcount = c->gcount;
586
  const int ti_current = r->e->ti_current;
587
588

  TIMER_TIC;
589

590
591
  /* Recurse? */
  if (c->split) {
Matthieu Schaller's avatar
Matthieu Schaller committed
592
    for (int k = 0; k < 8; k++)
593
      if (c->progeny[k] != NULL) runner_doinit(r, c->progeny[k], 0);
594
    return;
595
596
  } else {

597
598
    /* Loop over the parts in this cell. */
    for (int i = 0; i < count; i++) {
599

600
      /* Get a direct pointer on the part. */
601
      struct part *const p = &parts[i];
602

603
      if (p->ti_end <= ti_current) {
Matthieu Schaller's avatar
Matthieu Schaller committed
604

605
606
        /* Get ready for a density calculation */
        hydro_init_part(p);
607
      }
608
    }
609

610
    /* Loop over the gparts in this cell. */
611
612
613
    for (int i = 0; i < gcount; i++) {

      /* Get a direct pointer on the part. */
614
      struct gpart *const gp = &gparts[i];
615

616
      if (gp->ti_end <= ti_current) {
617
618

        /* Get ready for a density calculation */
619
        gravity_init_part(gp);
620
      }
621
622
    }
  }
623

Peter W. Draper's avatar
Peter W. Draper committed
624
  if (timer) TIMER_TOC(timer_init);
625
626
}

627
628
629
/**
 * @brief Intermediate task between density and force
 *
Pedro Gonnet's avatar
Pedro Gonnet committed
630
 * @param r The runner thread.
631
 * @param c The cell.
632
 */
633
634
635
636

void runner_doghost(struct runner *r, struct cell *c) {

  struct part *p, *parts = c->parts;
637
  struct xpart *xp, *xparts = c->xparts;
638
  struct cell *finger;
Matthieu Schaller's avatar
Matthieu Schaller committed
639
  int redo, count = c->count;
640
  int *pid;
641
  float h_corr;
642
643
  const int ti_current = r->e->ti_current;
  const double timeBase = r->e->timeBase;
644

645
646
  TIMER_TIC;

647
648
  /* Recurse? */
  if (c->split) {
Matthieu Schaller's avatar
Matthieu Schaller committed
649
    for (int k = 0; k < 8; k++)
650
651
652
653
654
655
656
      if (c->progeny[k] != NULL) runner_doghost(r, c->progeny[k]);
    return;
  }

  /* Init the IDs that have to be updated. */
  if ((pid = (int *)alloca(sizeof(int) * count)) == NULL)
    error("Call to alloca failed.");
Matthieu Schaller's avatar
Matthieu Schaller committed
657
  for (int k = 0; k < count; k++) pid[k] = k;
658
659

  /* While there are particles that need to be updated... */
Matthieu Schaller's avatar
Matthieu Schaller committed
660
  for (int num_reruns = 0; count > 0 && num_reruns < const_smoothing_max_iter;
Matthieu Schaller's avatar
Matthieu Schaller committed
661
       num_reruns++) {
662
663
664

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

666
    /* Loop over the parts in this cell. */
Matthieu Schaller's avatar
Matthieu Schaller committed
667
    for (int i = 0; i < count; i++) {
668
669
670

      /* Get a direct pointer on the part. */
      p = &parts[pid[i]];
671
      xp = &xparts[pid[i]];
672
673

      /* Is this part within the timestep? */
674
      if (p->ti_end <= ti_current) {
675

676
        /* Finish the density calculation */
677
        hydro_end_density(p, ti_current);
678
679

        /* If no derivative, double the smoothing length. */
680
        if (p->density.wcount_dh == 0.0f) h_corr = p->h;
681
682
683

        /* Otherwise, compute the smoothing length update (Newton step). */
        else {
684
          h_corr = (kernel_nwneigh - p->density.wcount) / p->density.wcount_dh;
685
686

          /* Truncate to the range [ -p->h/2 , p->h ]. */
687
688
          h_corr = fminf(h_corr, p->h);
          h_corr = fmaxf(h_corr, -p->h * 0.5f);
Pedro Gonnet's avatar
Pedro Gonnet committed
689
        }
690
691

        /* Did we get the right number density? */
692
        if (p->density.wcount > kernel_nwneigh + const_delta_nwneigh ||
693
            p->density.wcount < kernel_nwneigh - const_delta_nwneigh) {
694
695
696
697

          /* Ok, correct then */
          p->h += h_corr;

698
          /* Flag for another round of fun */
699
700
          pid[redo] = pid[i];
          redo += 1;
701

702
703
          /* Re-initialise everything */
          hydro_init_part(p);
704

705
          /* Off we go ! */
706
          continue;
707
708
        }

Matthieu Schaller's avatar
Matthieu Schaller committed
709
        /* We now have a particle whose smoothing length has converged */
Matthieu Schaller's avatar
Matthieu Schaller committed
710

711
        /* As of here, particle force variables will be set. */
712

713
        /* Compute variables required for the force loop */
714
        hydro_prepare_force(p, xp, ti_current, timeBase);
715

Matthieu Schaller's avatar
Matthieu Schaller committed
716
        /* The particle force values are now set.  Do _NOT_
717
           try to read any particle density variables! */
Matthieu Schaller's avatar
Matthieu Schaller committed
718

719
720
        /* Prepare the particle for the force loop over neighbours */
        hydro_reset_acceleration(p);
721
722
723
      }
    }

724
725
726
    /* We now need to treat the particles whose smoothing length had not
     * converged again */

727
728
729
730
731
732
    /* Re-set the counter for the next loop (potentially). */
    count = redo;
    if (count > 0) {

      /* Climb up the cell hierarchy. */
      for (finger = c; finger != NULL; finger = finger->parent) {
Matthieu Schaller's avatar
Matthieu Schaller committed
733

734
735
        /* 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
736

737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
          /* Self-interaction? */
          if (l->t->type == task_type_self)
            runner_doself_subset_density(r, finger, parts, pid, count);

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

            /* Left or right? */
            if (l->t->ci == finger)
              runner_dopair_subset_density(r, finger, parts, pid, count,
                                           l->t->cj);
            else
              runner_dopair_subset_density(r, finger, parts, pid, count,
                                           l->t->ci);

          }

          /* Otherwise, sub interaction? */
          else if (l->t->type == task_type_sub) {

            /* 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);
          }
        }
      }
767
    }
768
  }
769

Matthieu Schaller's avatar
Matthieu Schaller committed
770
771
  if (count)
    message("Smoothing length failed to converge on %i particles.", count);
772
773
774
775

  TIMER_TOC(timer_doghost);
}

776
/**
777
 * @brief Drift particles and g-particles forward in time
778
779
780
 *
 * @param r The runner thread.
 * @param c The cell.
781
 * @param timer Are we timing this ?
782
 */
783
void runner_dodrift(struct runner *r, struct cell *c, int timer) {
784

785
  const int nr_parts = c->count;
Tom Theuns's avatar
Tom Theuns committed
786
  const int nr_gparts = c->gcount;
787
788
  const double timeBase = r->e->timeBase;
  const double dt = (r->e->ti_current - r->e->ti_old) * timeBase;
789
790
791
792
793
  const int ti_old = r->e->ti_old;
  const int ti_current = r->e->ti_current;
  struct part *const parts = c->parts;
  struct xpart *const xparts = c->xparts;
  struct gpart *const gparts = c->gparts;
794
  float dx_max = 0.f, dx2_max = 0.f, h_max = 0.f;
795

796
  TIMER_TIC
Tom Theuns's avatar
Tom Theuns committed
797
#ifdef TASK_VERBOSE
Matthieu Schaller's avatar
Matthieu Schaller committed
798
  OUT;
Tom Theuns's avatar
Tom Theuns committed
799
#endif
800

801
802
  /* No children? */
  if (!c->split) {
803

804
805
806
807
808
809
810
811
812
813
814
815
816
    /* Loop over all the g-particles in the cell */
    for (int k = 0; k < nr_gparts; ++k) {

      /* Get a handle on the gpart. */
      struct gpart *const gp = &gparts[k];

      /* Drift... */
      gp->x[0] += gp->v_full[0] * dt;
      gp->x[1] += gp->v_full[1] * dt;
      gp->x[2] += gp->v_full[2] * dt;
    }

    /* Loop over all the particles in the cell (more work for these !) */
817
    for (int k = 0; k < nr_parts; k++) {
818

819
      /* Get a handle on the part. */
820
821
      struct part *const p = &parts[k];
      struct xpart *const xp = &xparts[k];
822

Matthieu Schaller's avatar
Matthieu Schaller committed
823
824
825
      /* Useful quantity */
      const float h_inv = 1.0f / p->h;

826
827
828
829
      /* Drift... */
      p->x[0] += xp->v_full[0] * dt;
      p->x[1] += xp->v_full[1] * dt;
      p->x[2] += xp->v_full[2] * dt;
830

Matthieu Schaller's avatar
Matthieu Schaller committed
831
      /* Predict velocities (for hydro terms) */
Matthieu Schaller's avatar
Matthieu Schaller committed
832
833
834
      p->v[0] += p->a_hydro[0] * dt;
      p->v[1] += p->a_hydro[1] * dt;
      p->v[2] += p->a_hydro[2] * dt;
835

Matthieu Schaller's avatar
Matthieu Schaller committed
836
      /* Predict smoothing length */
837
838
839
      const float w1 = p->h_dt * h_inv * dt;
      if (fabsf(w1) < 0.2f)
        p->h *= approx_expf(w1); /* 4th order expansion of exp(w) */
Matthieu Schaller's avatar
Matthieu Schaller committed
840
      else
841
        p->h *= expf(w1);
Matthieu Schaller's avatar
Matthieu Schaller committed
842
843

      /* Predict density */
844
845
846
      const float w2 = -3.0f * p->h_dt * h_inv * dt;
      if (fabsf(w2) < 0.2f)
        p->rho *= approx_expf(w2); /* 4th order expansion of exp(w) */
Matthieu Schaller's avatar
Matthieu Schaller committed
847
      else
848
        p->rho *= expf(w2);
849

850
      /* Predict the values of the extra fields */
851
      hydro_predict_extra(p, xp, ti_old, ti_current, timeBase);
852

853
      /* Compute (square of) motion since last cell construction */
854
855
856
857
      const float dx2 = (p->x[0] - xp->x_old[0]) * (p->x[0] - xp->x_old[0]) +
                        (p->x[1] - xp->x_old[1]) * (p->x[1] - xp->x_old[1]) +
                        (p->x[2] - xp->x_old[2]) * (p->x[2] - xp->x_old[2]);
      dx2_max = fmaxf(dx2_max, dx2);
Matthieu Schaller's avatar
Matthieu Schaller committed
858
859
860

      /* Maximal smoothing length */
      h_max = fmaxf(p->h, h_max);
861
    }
862

863
    /* Now, get the maximal particle motion from its square */
864
    dx_max = sqrtf(dx2_max);
865
  }
866

Matthieu Schaller's avatar
Matthieu Schaller committed
867
868
869
870
871
872
873
874
875
  /* Otherwise, aggregate data from children. */
  else {

    /* Loop over the progeny. */
    for (int k = 0; k < 8; k++)
      if (c->progeny[k] != NULL) {
        struct cell *cp = c->progeny[k];
        runner_dodrift(r, cp, 0);

876
877
        dx_max = fmaxf(dx_max, cp->dx_max);
        h_max = fmaxf(h_max, cp->h_max);
Matthieu Schaller's avatar
Matthieu Schaller committed
878
879
880
881
882
883
      }
  }

  /* Store the values */
  c->h_max = h_max;
  c->dx_max = dx_max;
884

Peter W. Draper's avatar
Peter W. Draper committed
885
  if (timer) TIMER_TOC(timer_drift);
886
}
887

888
889
890
891
892
/**
 * @brief Combined second and first kick for fixed dt.
 *
 * @param r The runner thread.
 * @param c The cell.
893
 * @param timer The timer
894
895
 */

896
897
void runner_dokick(struct runner *r, struct cell *c, int timer) {

898
899
  const float global_dt_min = r->e->dt_min;
  const float global_dt_max = r->e->dt_max;
900
  const int ti_current = r->e->ti_current;
901
902
  const double timeBase = r->e->timeBase;
  const double timeBase_inv = 1.0 / r->e->timeBase;
Matthieu Schaller's avatar
Matthieu Schaller committed
903
  const int count = c->count;
Tom Theuns's avatar
Tom Theuns committed
904
  const int gcount = c->gcount;
905
906
907
  struct part *const parts = c->parts;
  struct xpart *const xparts = c->xparts;
  struct gpart *const gparts = c->gparts;
908
909
  const int is_fixdt =
      (r->e->policy & engine_policy_fixdt) == engine_policy_fixdt;
Matthieu Schaller's avatar
Matthieu Schaller committed
910

911
  int updated = 0, g_updated = 0;
912
  int ti_end_min = max_nr_timesteps, ti_end_max = 0;
913
914
915
  double e_kin = 0.0, e_int = 0.0, e_pot = 0.0, mass = 0.0;
  float mom[3] = {0.0f, 0.0f, 0.0f};
  float ang[3] = {0.0f, 0.0f, 0.0f};
916
917
918

  TIMER_TIC

Tom Theuns's avatar
Tom Theuns committed
919
#ifdef TASK_VERBOSE
Matthieu Schaller's avatar
Matthieu Schaller committed
920
  OUT;
Tom Theuns's avatar
Tom Theuns committed
921
922
#endif

923
924
925
  /* No children? */
  if (!c->split) {

926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
    /* Loop over the g-particles and kick the active ones. */
    for (int k = 0; k < gcount; k++) {

      /* Get a handle on the part. */
      struct gpart *const gp = &gparts[k];

      /* If the g-particle has no counterpart and needs to be kicked */
      if (gp->id < 0 && (is_fixdt || gp->ti_end <= ti_current)) {

        /* First, finish the force calculation */
        gravity_end_force(gp);

        /* Now we are ready to compute the next time-step size */
        int new_dti;

        if (is_fixdt) {

          /* Now we have a time step, proceed with the kick */
          new_dti = global_dt_max * timeBase_inv;

        } else {

          /* Compute the next timestep (gravity condition) */
949
          float new_dt = gravity_compute_timestep(r->e->physical_constants, gp);
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977

          /* Limit timestep within the allowed range */
          new_dt = fminf(new_dt, global_dt_max);
          new_dt = fmaxf(new_dt, global_dt_min);

          /* Convert to integer time */
          new_dti = new_dt * timeBase_inv;

          /* Recover the current timestep */
          const int current_dti = gp->ti_end - gp->ti_begin;

          /* Limit timestep increase */
          if (current_dti > 0) new_dti = min(new_dti, 2 * current_dti);

          /* Put this timestep on the time line */
          int dti_timeline = max_nr_timesteps;
          while (new_dti < dti_timeline) dti_timeline /= 2;

          /* Now we have a time step, proceed with the kick */
          new_dti = dti_timeline;
        }

        /* Compute the time step for this kick */
        const int ti_start = (gp->ti_begin + gp->ti_end) / 2;
        const int ti_end = gp->ti_end + new_dti / 2;
        const double dt = (ti_end - ti_start) * timeBase;
        const double half_dt = (ti_end - gp->ti_end) * timeBase;

Matthieu Schaller's avatar
Matthieu Schaller committed
978
        /* Move particle forward in time */
979
980
981
        gp->ti_begin = gp->ti_end;
        gp->ti_end = gp->ti_begin + new_dti;

982
983
984
985
986
987
988
989
990
991
992
        /* Kick particles in momentum space */
        gp->v_full[0] += gp->a_grav[0] * dt;
        gp->v_full[1] += gp->a_grav[1] * dt;
        gp->v_full[2] += gp->a_grav[2] * dt;

        /* Extra kick work */
        gravity_kick_extra(gp, dt, half_dt);

        /* Number of updated g-particles */
        g_updated++;
      }
993

Matthieu Schaller's avatar
Matthieu Schaller committed
994
995
996
      /* Minimal time for next end of time-step */
      ti_end_min = min(gp->ti_end, ti_end_min);
      ti_end_max = max(gp->ti_end, ti_end_max);
997
998
999
1000
    }

    /* Now do the hydro ones... */