queue.c 6.94 KB
Newer Older
1
/*******************************************************************************
2
 * This file is part of SWIFT.
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
 * Coypright (c) 2012 Pedro Gonnet (pedro.gonnet@durham.ac.uk)
 * 
 * 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.
 * 
 * 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.
 * 
 * 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/>.
 * 
 ******************************************************************************/

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

/* Some standard headers. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

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

33
/* Local headers. */
34
#include "const.h"
35
36
37
#include "cycle.h"
#include "lock.h"
#include "task.h"
Pedro Gonnet's avatar
Pedro Gonnet committed
38
#include "timers.h"
39
#include "space.h"
40
41
#include "part.h"
#include "multipole.h"
42
43
#include "cell.h"
#include "queue.h"
44
45
#include "error.h"
#include "inline.h"
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61



/* Counter macros. */
#ifdef COUNTER
    #define COUNT(c) ( __sync_add_and_fetch( &queue_counter[ c ] , 1 ) )
#else
    #define COUNT(c)
#endif


/* The counters. */
int queue_counter[ queue_counter_count ];

        

Pedro Gonnet's avatar
Pedro Gonnet committed
62
63
64
65
66
67
68
69
70
/**
 * @brief Insert a used tasks into the given queue.
 *
 * @param q The #queue.
 * @param t The #task.
 */
 
void queue_insert ( struct queue *q , struct task *t ) {

71
72
73
    int k, *tid;
    struct task *tasks;

Pedro Gonnet's avatar
Pedro Gonnet committed
74
75
76
77
    /* Lock the queue. */
    if ( lock_lock( &q->lock ) != 0 )
        error( "Failed to get queue lock." );
        
78
79
80
    tid = q->tid;
    tasks = q->tasks;

81
82
83
84
85
86
    /* Does the queue need to be grown? */
    if ( q->count == q->size ) {
        int *temp;
        q->size *= queue_sizegrow;
        if ( ( temp = (int *)malloc( sizeof(int) * q->size ) ) == NULL )
            error( "Failed to allocate new indices." );
87
88
89
        memcpy( temp , tid , sizeof(int) * q->count );
        free( tid );
        q->tid = tid = temp;
90
91
92
        }
        
    /* Drop the task at the end of the queue. */
93
    tid[ q->count ] = ( t - tasks );
Pedro Gonnet's avatar
Pedro Gonnet committed
94
    q->count += 1;
95
96
    
    /* Shuffle up. */
97
98
99
100
101
    for ( k = q->count - 1 ; k > 0 ; k = (k-1)/2 )
        if ( tasks[ tid[k] ].weight > tasks[ tid[(k-1)/2] ].weight ) {
            int temp = tid[k];
            tid[k] = tid[(k-1)/2];
            tid[(k-1)/2] = temp;
102
103
            }
        else
Pedro Gonnet's avatar
Pedro Gonnet committed
104
            break;
105
106
107
108
109
            
    /* Check the queue's consistency. */
    /* for ( k = 1 ; k < q->count ; k++ )
        if ( tasks[ tid[(k-1)/2] ].weight < tasks[ tid[k] ].weight )
            error( "Queue heap is disordered." ); */
Pedro Gonnet's avatar
Pedro Gonnet committed
110
111
112
113
114
115
116
    
    /* Unlock the queue. */
    if ( lock_unlock( &q->lock ) != 0 )
        error( "Failed to unlock queue." );
    }


117
118
119
120
121
122
123
/** 
 * @brief Initialize the given queue.
 *
 * @param q The #queue.
 * @param tasks List of tasks to which the queue indices refer to.
 */
 
124
void queue_init ( struct queue *q , struct task *tasks ) {
125
    
126
    /* Allocate the task list if needed. */
127
128
129
    q->size = queue_sizeinit;
    if ( ( q->tid = (int *)malloc( sizeof(int) * q->size ) ) == NULL )
        error( "Failed to allocate queue tids." );
130
131
        
    /* Set the tasks pointer. */
132
133
134
135
136
137
138
139
140
141
    q->tasks = tasks;
        
    /* Init counters. */
    q->count = 0;
    
    /* Init the queue lock. */
    if ( lock_init( &q->lock ) != 0 )
        error( "Failed to init queue lock." );

    }
142
143
    
    
144
145
146
147
/**
 * @brief Get a task free of dependencies and conflicts.
 *
 * @param q The task #queue.
148
 * @param super The super-cell tat might conflict with the #queue
149
150
151
 * @param blocking Block until access to the queue is granted.
 */
 
152
struct task *queue_gettask ( struct queue *q , struct cell *super , int blocking ) {
153

154
    int k, qcount, *qtid, gotcha;
155
    lock_type *qlock = &q->lock;
156
    struct task *qtasks, *res = NULL;
157
158
    
    /* If there are no tasks, leave immediately. */
Pedro Gonnet's avatar
Pedro Gonnet committed
159
    if ( q->count == 0 )
160
161
        return NULL;

162
163
164
165
166
167
168
169
170
    /* Grab the task lock. */
    if ( blocking ) {
        if ( lock_lock( qlock ) != 0 )
            error( "Locking the qlock failed.\n" );
        }
    else {
        if ( lock_trylock( qlock ) != 0 )
            return NULL;
        }
171

172
173
174
175
176
    /* Set some pointers we will use often. */
    qtid = q->tid;
    qtasks = q->tasks;
    qcount = q->count;
    gotcha = 0;
177

178
179
180
    /* Loop over the task IDs looking for tasks with the same super-cell. */
    if ( super != NULL ) {
        for ( k = 0 ; k < qcount && k < queue_maxsuper ; k++ ) {
181

182
183
            /* Put a finger on the task. */
            res = &qtasks[ qtid[k] ];
184

185
186
187
188
189
190
            /* Try to lock the task and exit if successful. */
            if ( ( res->ci->super == super || ( res->cj != NULL && res->cj->super == super ) ) &&
                 task_lock( res ) ) {
                gotcha = 1;
                break;
                }
Pedro Gonnet's avatar
Pedro Gonnet committed
191

192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
            } /* loop over the task IDs. */
        }

    /* Loop over the task IDs again if nothing was found, take anything. */
    if ( !gotcha ) {
        for ( k = 0 ; k < qcount ; k++ ) {

            /* Put a finger on the task. */
            res = &qtasks[ qtid[k] ];

            /* Try to lock the task and exit if successful. */
            if ( task_lock( res ) )
                break;

            } /* loop over the task IDs. */
        }

    /* Did we get a task? */
    if ( k < qcount ) {

        /* Another one bites the dust. */
        qcount = q->count -= 1;

        /* Swap this task with the last task and re-heap. */
        if ( k < qcount ) {
            qtid[ k ] = qtid[ qcount ];
218
219
            int w = qtasks[ qtid[k] ].weight;
            while ( k > 0 && w > qtasks[ qtid[(k-1)/2] ].weight ) {
220
221
222
223
224
225
226
227
228
                int temp = q->tid[k];
                q->tid[k] = q->tid[(k-1)/2];
                q->tid[(k-1)/2] = temp;
                k = (k-1)/2;
                }
            int i;
            while ( ( i = 2*k+1 ) < qcount ) {
                if ( i+1 < qcount && qtasks[ qtid[i+1] ].weight > qtasks[ qtid[i] ].weight )
                    i += 1;
229
230
                if ( qtasks[ qtid[i] ].weight > w ) {
                    int temp = qtid[i];
231
232
233
                    qtid[i] = qtid[k];
                    qtid[k] = temp;
                    k = i;
234
                    }
235
236
                else
                    break;
Pedro Gonnet's avatar
Pedro Gonnet committed
237
                }
Pedro Gonnet's avatar
Pedro Gonnet committed
238
            }
239
240
241
242
243

        }
    else
        res = NULL;

244
245
246
247
248
    /* Check the queue's consistency. */
    /* for ( k = 1 ; k < q->count ; k++ )
        if ( qtasks[ qtid[(k-1)/2] ].weight < qtasks[ qtid[k] ].weight )
            error( "Queue heap is disordered." ); */
    
249
250
251
    /* Release the task lock. */
    if ( lock_unlock( qlock ) != 0 )
        error( "Unlocking the qlock failed.\n" );
Pedro Gonnet's avatar
Pedro Gonnet committed
252
            
Pedro Gonnet's avatar
Pedro Gonnet committed
253
    /* Take the money and run. */
254
    return res;
255
256
257
258

    }