1
2
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
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
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
|
/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* 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 General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* The Original Code is Copyright (C) 2008 by Blender Foundation.
* All rights reserved.
*/
/** \file
* \ingroup bli
*
* Dead simple, fast memory allocator for allocating many elements of the same size.
*
*/
#include <string.h>
#include <stdlib.h>
#include "atomic_ops.h"
#include "BLI_utildefines.h"
#include "BLI_memblock.h" /* own include */
#include "MEM_guardedalloc.h"
#include "BLI_strict_flags.h" /* keep last */
#define BLI_MEM_BLOCK_CHUNK_SIZE (1 << 15) /* 32KiB */
#define CHUNK_LIST_SIZE 16
struct BLI_memblock {
void **chunk_list;
/** Element size in bytes. */
uint elem_size;
/** First unused element index. */
uint elem_next;
/** Chunck size in bytes. */
uint chunk_size;
/** Number of allocated chunck. */
uint chunk_len;
};
BLI_memblock *BLI_memblock_create(uint elem_size)
{
BLI_assert(elem_size < BLI_MEM_BLOCK_CHUNK_SIZE);
BLI_memblock *mblk = MEM_mallocN(sizeof(BLI_memblock), "BLI_memblock");
mblk->elem_size = elem_size;
mblk->elem_next = 0;
mblk->chunk_size = BLI_MEM_BLOCK_CHUNK_SIZE;
mblk->chunk_len = CHUNK_LIST_SIZE;
mblk->chunk_list = MEM_callocN(sizeof(void *) * mblk->chunk_len, "BLI_memblock chunk list");
return mblk;
}
void BLI_memblock_destroy(BLI_memblock *mblk)
{
for (uint i = 0; i < mblk->chunk_len; i++) {
MEM_SAFE_FREE(mblk->chunk_list[i]);
}
MEM_SAFE_FREE(mblk->chunk_list);
MEM_freeN(mblk);
}
/* Reset elem count to 0 but keep as much memory allocated needed for at least the previous elem
* count. */
void BLI_memblock_clear(BLI_memblock *mblk)
{
uint elem_per_chunk = mblk->chunk_size / mblk->elem_size;
uint last_used_chunk = (mblk->elem_next - 1) / elem_per_chunk;
for (uint i = last_used_chunk + 1; i < mblk->chunk_len; i++) {
MEM_SAFE_FREE(mblk->chunk_list[i]);
}
if (UNLIKELY(last_used_chunk + 1 < mblk->chunk_len - CHUNK_LIST_SIZE)) {
mblk->chunk_len -= CHUNK_LIST_SIZE;
mblk->chunk_list = MEM_recallocN(mblk->chunk_list, sizeof(void *) * mblk->chunk_len);
}
mblk->elem_next = 0;
}
void *BLI_memblock_alloc(BLI_memblock *mblk)
{
uint elem_per_chunk = mblk->chunk_size / mblk->elem_size;
uint chunk_idx = mblk->elem_next / elem_per_chunk;
uint elem_idx = mblk->elem_next - elem_per_chunk * chunk_idx;
mblk->elem_next++;
if (UNLIKELY(chunk_idx >= mblk->chunk_len)) {
mblk->chunk_len += CHUNK_LIST_SIZE;
mblk->chunk_list = MEM_recallocN(mblk->chunk_list, sizeof(void *) * mblk->chunk_len);
}
if (UNLIKELY(mblk->chunk_list[chunk_idx] == NULL)) {
mblk->chunk_list[chunk_idx] = MEM_mallocN(mblk->chunk_size, "BLI_memblock chunk");
}
return (char *)(mblk->chunk_list[chunk_idx]) + mblk->elem_size * elem_idx;
}
void BLI_memblock_iternew(BLI_memblock *mblk, BLI_memblock_iter *iter)
{
iter->mblk = mblk;
iter->current_index = 0;
iter->elem_per_chunk = mblk->chunk_size / mblk->elem_size;
}
void *BLI_memblock_iterstep(BLI_memblock_iter *iter)
{
if (iter->current_index >= iter->mblk->elem_next) {
return NULL;
}
uint chunk_idx = iter->current_index / iter->elem_per_chunk;
uint elem_idx = iter->current_index - iter->elem_per_chunk * chunk_idx;
iter->current_index++;
return (char *)(iter->mblk->chunk_list[chunk_idx]) + iter->mblk->elem_size * elem_idx;
}
|
