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
|
#include "kpl.h"
void kpl_memory_allocator_init(kpl_memory_allocator *memory_allocator) {
for (int32_t slab_pow2 = KPL_MEMORY_ALLOCATOR_MIN_SIZE_POW2;
slab_pow2 <= KPL_MEMORY_ALLOCATOR_MAX_SIZE_POW2; slab_pow2++) {
kpl_memory_allocator_slab_group *slab_group = &memory_allocator->slabs[slab_pow2];
slab_group->slab_size_pow2 = slab_pow2;
slab_group->slab_head = slab_group->slab_tail = NULL;
kpl_object_queue_init(&slab_group->object_pool);
}
}
static void kpl_memory_allocator_slab_free(kpl_memory_allocator_slab_group *slab_group) {
kpl_memory_allocator_slab *slab_head = slab_group->slab_head;
while (slab_head) {
kpl_memory_allocator_slab *slab_tmp = slab_head;
slab_head = slab_head->slab_next;
munmap(slab_tmp->buffer, slab_tmp->buffer_size);
free(slab_tmp);
}
}
void kpl_memory_allocator_free(kpl_memory_allocator *memory_allocator) {
for (int32_t slab_pow2 = KPL_MEMORY_ALLOCATOR_MIN_SIZE_POW2;
slab_pow2 < KPL_MEMORY_ALLOCATOR_SLAB_COUNT; slab_pow2++) {
kpl_memory_allocator_slab_group *slab_group = &memory_allocator->slabs[slab_pow2];
#ifdef KPL_VALGRIND
kpl_object *object = NULL;
while ((object = kpl_object_queue_dequeue(&slab_group->object_pool)))
VALGRIND_FREELIKE_BLOCK(object, 0);
#endif
kpl_memory_allocator_slab_free(slab_group);
}
}
static int32_t kpl_memory_allocator_get_size_pow2(int32_t size) {
return size > 1 ? 32 - __builtin_clz(size - 1) : 0;
}
static const int32_t pages_per_pow2[] = {
[5] = 5,
[6] = 10,
[7] = 15,
[8] = 20,
[9] = 25,
[10] = 30,
[11] = 35,
[12] = 40,
[13] = 2,
[14] = 4,
[15] = 8,
[16] = 16,
[17] = 32,
[18] = 64,
[19] = 128,
[20] = 256,
[21] = 512,
[22] = 1024,
};
static kpl_memory_allocator_slab *kpl_memory_allocator_slab_init(int32_t size_pow2) {
kpl_memory_allocator_slab *slab = calloc(1, sizeof(kpl_memory_allocator_slab));
slab->buffer_size = getpagesize() * pages_per_pow2[size_pow2];
slab->buffer = mmap(NULL, slab->buffer_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_SHARED, -1, 0);
return slab;
}
static void *kpl_memory_allocator_slab_bump(kpl_memory_allocator_slab *slab, int32_t size) {
void *object = slab->buffer + slab->buffer_used;
slab->buffer_used += size;
return object;
}
static kpl_object *kpl_memory_allocator_slab_allocate(kpl_memory_allocator_slab_group *slab_group,
int32_t thread_id) {
kpl_memory_allocator_slab *slab = slab_group->slab_tail;
int32_t size = 1 << slab_group->slab_size_pow2;
if (!slab || slab->buffer_used + size > slab->buffer_size) {
slab = kpl_memory_allocator_slab_init(slab_group->slab_size_pow2);
if (!slab_group->slab_head)
slab_group->slab_head = slab_group->slab_tail = slab;
else
slab_group->slab_tail = slab_group->slab_tail->slab_next = slab;
}
kpl_object *object = kpl_memory_allocator_slab_bump(slab, size);
#ifdef KPL_VALGRIND
VALGRIND_MALLOCLIKE_BLOCK(object, size, 0, 0);
#endif
__atomic_store_n(&object->queue_next, NULL, __ATOMIC_RELAXED);
object->object_size = size;
object->thread_id = thread_id;
return object;
}
void *kpl_memory_allocator_allocate(kpl_memory_allocator *memory_allocator, int32_t size, int32_t thread_id) {
if (size < (1 << KPL_MEMORY_ALLOCATOR_MIN_ROUND_SIZE_POW2))
return NULL;
int32_t size_pow2 = kpl_memory_allocator_get_size_pow2(size);
if (size_pow2 < KPL_MEMORY_ALLOCATOR_MIN_SIZE_POW2)
size_pow2 = KPL_MEMORY_ALLOCATOR_MIN_SIZE_POW2;
kpl_memory_allocator_slab_group *slab_group = &memory_allocator->slabs[size_pow2];
kpl_object *object = kpl_object_queue_dequeue(&slab_group->object_pool);
if (!object)
object = kpl_memory_allocator_slab_allocate(slab_group, thread_id);
return object;
}
void kpl_memory_allocator_return(kpl_memory_allocator *memory_allocator, void *object) {
int32_t size_pow2 = kpl_memory_allocator_get_size_pow2(((kpl_object*) object)->object_size);
kpl_object_queue_enqueue(&memory_allocator->slabs[size_pow2].object_pool, object);
}
|
