task.c 6.46 KB
Newer Older
1
/*******************************************************************************
2
 * This file is part of SWIFT.
3
 * Copyright (c) 2012 Pedro Gonnet (pedro.gonnet@durham.ac.uk)
4
 *                    Matthieu Schaller (matthieu.schaller@durham.ac.uk)
5
 *
6
7
8
9
 * 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.
10
 *
11
12
13
14
 * 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.
15
 *
16
17
 * 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/>.
18
 *
19
20
21
22
23
24
25
26
27
 ******************************************************************************/

/* Config parameters. */
#include "../config.h"

/* Some standard headers. */
#include <float.h>
#include <limits.h>
#include <sched.h>
28
29
30
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
31

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

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

40
/* Local headers. */
Pedro Gonnet's avatar
Pedro Gonnet committed
41
#include "atomic.h"
42
#include "error.h"
43
#include "lock.h"
44
45

/* Task type names. */
46
const char *taskID_names[task_type_count] = {
47
48
49
    "none",    "sort",    "self",    "pair",     "sub",  "init",
    "ghost",   "drift",   "kick",    "send",     "recv", "link",
    "grav_pp", "grav_mm", "grav_up", "grav_down"};
50

51
52
/**
 * @brief Unlock the cell held by this task.
53
 *
54
55
56
 * @param t The #task.
 */

57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
void task_unlock(struct task *t) {

  /* Act based on task type. */
  switch (t->type) {
    case task_type_self:
    case task_type_sort:
      cell_unlocktree(t->ci);
      break;
    case task_type_pair:
    case task_type_sub:
      cell_unlocktree(t->ci);
      if (t->cj != NULL) cell_unlocktree(t->cj);
      break;
    case task_type_grav_pp:
    case task_type_grav_mm:
    case task_type_grav_down:
      cell_gunlocktree(t->ci);
      if (t->cj != NULL) cell_gunlocktree(t->cj);
      break;
    default:
      break;
  }
}
80
81
82
83
84
85

/**
 * @brief Try to lock the cells associated with this task.
 *
 * @param t the #task.
 */
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104

int task_lock(struct task *t) {

  int type = t->type;
  struct cell *ci = t->ci, *cj = t->cj;

  /* Communication task? */
  if (type == task_type_recv || type == task_type_send) {

#ifdef WITH_MPI
    /* Check the status of the MPI request. */
    int res, err;
    MPI_Status stat;
    if ((err = MPI_Test(&t->req, &res, &stat)) != MPI_SUCCESS) {
      char buff[MPI_MAX_ERROR_STRING];
      int len;
      MPI_Error_string(err, buff, &len);
      error("Failed to test request on send/recv task (tag=%i, %s).", t->flags,
            buff);
105
    }
106
107
108
109
    return res;
#else
    error("SWIFT was not compiled with MPI support.");
#endif
110

111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
  }

  /* Unary lock? */
  else if (type == task_type_self || type == task_type_sort ||
           (type == task_type_sub && cj == NULL)) {
    if (cell_locktree(ci) != 0) return 0;
  }

  /* Otherwise, binary lock. */
  else if (type == task_type_pair || (type == task_type_sub && cj != NULL)) {
    if (ci->hold || cj->hold) return 0;
    if (cell_locktree(ci) != 0) return 0;
    if (cell_locktree(cj) != 0) {
      cell_unlocktree(ci);
      return 0;
    }
  }

  /* Gravity tasks? */
  else if (type == task_type_grav_mm || type == task_type_grav_pp ||
           type == task_type_grav_down) {
    if (ci->ghold || (cj != NULL && cj->ghold)) return 0;
    if (cell_glocktree(ci) != 0) return 0;
    if (cj != NULL && cell_glocktree(cj) != 0) {
      cell_gunlocktree(ci);
      return 0;
    }
  }

  /* If we made it this far, we've got a lock. */
  return 1;
}
143

144
/**
145
 * @brief Remove all unlocks to tasks that are of the given type.
146
147
148
149
 *
 * @param t The #task.
 * @param type The task type ID to remove.
 */
150
151
152
153
154
155
156
157
158
159
160

void task_cleanunlock(struct task *t, int type) {

  int k;

  lock_lock(&t->lock);

  for (k = 0; k < t->nr_unlock_tasks; k++)
    if (t->unlock_tasks[k]->type == type) {
      t->nr_unlock_tasks -= 1;
      t->unlock_tasks[k] = t->unlock_tasks[t->nr_unlock_tasks];
161
162
    }

163
164
  lock_unlock_blind(&t->lock);
}
165

166
167
168
169
170
171
172
/**
 * @brief Remove an unlock_task from the given task.
 *
 * @param ta The unlocking #task.
 * @param tb The #task that will be unlocked.
 */

173
174
175
176
177
178
179
180
181
182
183
184
void task_rmunlock(struct task *ta, struct task *tb) {

  int k;

  lock_lock(&ta->lock);

  for (k = 0; k < ta->nr_unlock_tasks; k++)
    if (ta->unlock_tasks[k] == tb) {
      ta->nr_unlock_tasks -= 1;
      ta->unlock_tasks[k] = ta->unlock_tasks[ta->nr_unlock_tasks];
      lock_unlock_blind(&ta->lock);
      return;
185
    }
186
187
  error("Task not found.");
}
188

Pedro Gonnet's avatar
Pedro Gonnet committed
189
190
191
192
193
194
195
196
197
198
/**
 * @brief Remove an unlock_task from the given task.
 *
 * @param ta The unlocking #task.
 * @param tb The #task that will be unlocked.
 *
 * Differs from #task_rmunlock in that it will not fail if
 * the task @c tb is not in the unlocks of @c ta.
 */

199
200
201
202
203
204
205
206
207
208
209
void task_rmunlock_blind(struct task *ta, struct task *tb) {

  int k;

  lock_lock(&ta->lock);

  for (k = 0; k < ta->nr_unlock_tasks; k++)
    if (ta->unlock_tasks[k] == tb) {
      ta->nr_unlock_tasks -= 1;
      ta->unlock_tasks[k] = ta->unlock_tasks[ta->nr_unlock_tasks];
      break;
Pedro Gonnet's avatar
Pedro Gonnet committed
210
    }
211
212
213

  lock_unlock_blind(&ta->lock);
}
Pedro Gonnet's avatar
Pedro Gonnet committed
214

215
216
217
218
219
220
/**
 * @brief Add an unlock_task to the given task.
 *
 * @param ta The unlocking #task.
 * @param tb The #task that will be unlocked.
 */
221

222
void task_addunlock(struct task *ta, struct task *tb) {
223

224
  error("Use sched_addunlock instead.");
225

226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
  /* Add the lock atomically. */
  ta->unlock_tasks[atomic_inc(&ta->nr_unlock_tasks)] = tb;

  /* Check a posteriori if we did not overshoot. */
  if (ta->nr_unlock_tasks > task_maxunlock)
    error("Too many unlock_tasks in task.");
}

void task_addunlock_old(struct task *ta, struct task *tb) {

  int k;

  lock_lock(&ta->lock);

  /* Check if ta already unlocks tb. */
  for (k = 0; k < ta->nr_unlock_tasks; k++)
    if (ta->unlock_tasks[k] == tb) {
      error("Duplicate unlock.");
      lock_unlock_blind(&ta->lock);
      return;
246
247
    }

248
249
250
251
252
253
254
255
  if (ta->nr_unlock_tasks == task_maxunlock)
    error("Too many unlock_tasks in task.");

  ta->unlock_tasks[ta->nr_unlock_tasks] = tb;
  ta->nr_unlock_tasks += 1;

  lock_unlock_blind(&ta->lock);
}
256
257
258
259
260
261
262
263
264
265

void task_print_mask(unsigned int mask) {

  int k;

  printf("task_print_mask: The tasks to run are [");
  for (k = 1; k < task_type_count; k++)
    printf(" %s=%s", taskID_names[k], (mask & (1 << k)) ? "yes" : "no");
  printf(" ]\n");
}