blob: 83a68723ded61b66d66c9b38a1cdf58b0ee7fce0 (
plain)
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
135
136
137
138
139
140
141
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
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
#include "Python.h"
#include "pycore_lock.h" // PyMutex_LockFlags()
#include "pycore_pystate.h" // _PyThreadState_GET()
#include "pycore_object.h" // _Py_IncRefTotal
#include "pycore_typeid.h"
// This contains code for allocating unique ids to heap type objects
// and re-using those ids when the type is deallocated.
//
// See Include/internal/pycore_typeid.h for more details.
#ifdef Py_GIL_DISABLED
#define POOL_MIN_SIZE 8
#define LOCK_POOL(pool) PyMutex_LockFlags(&pool->mutex, _Py_LOCK_DONT_DETACH)
#define UNLOCK_POOL(pool) PyMutex_Unlock(&pool->mutex)
static int
resize_interp_type_id_pool(struct _Py_type_id_pool *pool)
{
if ((size_t)pool->size > PY_SSIZE_T_MAX / (2 * sizeof(*pool->table))) {
return -1;
}
Py_ssize_t new_size = pool->size * 2;
if (new_size < POOL_MIN_SIZE) {
new_size = POOL_MIN_SIZE;
}
_Py_type_id_entry *table = PyMem_Realloc(pool->table,
new_size * sizeof(*pool->table));
if (table == NULL) {
return -1;
}
Py_ssize_t start = pool->size;
for (Py_ssize_t i = start; i < new_size - 1; i++) {
table[i].next = &table[i + 1];
}
table[new_size - 1].next = NULL;
pool->table = table;
pool->freelist = &table[start];
_Py_atomic_store_ssize(&pool->size, new_size);
return 0;
}
static int
resize_local_refcounts(_PyThreadStateImpl *tstate)
{
if (tstate->types.is_finalized) {
return -1;
}
struct _Py_type_id_pool *pool = &tstate->base.interp->type_ids;
Py_ssize_t size = _Py_atomic_load_ssize(&pool->size);
Py_ssize_t *refcnts = PyMem_Realloc(tstate->types.refcounts,
size * sizeof(Py_ssize_t));
if (refcnts == NULL) {
return -1;
}
Py_ssize_t old_size = tstate->types.size;
if (old_size < size) {
memset(refcnts + old_size, 0, (size - old_size) * sizeof(Py_ssize_t));
}
tstate->types.refcounts = refcnts;
tstate->types.size = size;
return 0;
}
void
_PyType_AssignId(PyHeapTypeObject *type)
{
PyInterpreterState *interp = _PyInterpreterState_GET();
struct _Py_type_id_pool *pool = &interp->type_ids;
LOCK_POOL(pool);
if (pool->freelist == NULL) {
if (resize_interp_type_id_pool(pool) < 0) {
type->unique_id = -1;
UNLOCK_POOL(pool);
return;
}
}
_Py_type_id_entry *entry = pool->freelist;
pool->freelist = entry->next;
entry->type = type;
_PyObject_SetDeferredRefcount((PyObject *)type);
type->unique_id = (entry - pool->table);
UNLOCK_POOL(pool);
}
void
_PyType_ReleaseId(PyHeapTypeObject *type)
{
PyInterpreterState *interp = _PyInterpreterState_GET();
struct _Py_type_id_pool *pool = &interp->type_ids;
if (type->unique_id < 0) {
// The type doesn't have an id assigned.
return;
}
LOCK_POOL(pool);
_Py_type_id_entry *entry = &pool->table[type->unique_id];
assert(entry->type == type);
entry->next = pool->freelist;
pool->freelist = entry;
type->unique_id = -1;
UNLOCK_POOL(pool);
}
void
_PyType_IncrefSlow(PyHeapTypeObject *type)
{
_PyThreadStateImpl *tstate = (_PyThreadStateImpl *)_PyThreadState_GET();
if (type->unique_id < 0 || resize_local_refcounts(tstate) < 0) {
// just incref the type directly.
Py_INCREF(type);
return;
}
assert(type->unique_id < tstate->types.size);
tstate->types.refcounts[type->unique_id]++;
#ifdef Py_REF_DEBUG
_Py_IncRefTotal((PyThreadState *)tstate);
#endif
_Py_INCREF_STAT_INC();
}
void
_PyType_MergeThreadLocalRefcounts(_PyThreadStateImpl *tstate)
{
if (tstate->types.refcounts == NULL) {
return;
}
struct _Py_type_id_pool *pool = &tstate->base.interp->type_ids;
LOCK_POOL(pool);
for (Py_ssize_t i = 0, n = tstate->types.size; i < n; i++) {
Py_ssize_t refcnt = tstate->types.refcounts[i];
if (refcnt != 0) {
PyObject *type = (PyObject *)pool->table[i].type;
assert(PyType_Check(type));
_Py_atomic_add_ssize(&type->ob_ref_shared,
refcnt << _Py_REF_SHARED_SHIFT);
tstate->types.refcounts[i] = 0;
}
}
UNLOCK_POOL(pool);
}
void
_PyType_FinalizeThreadLocalRefcounts(_PyThreadStateImpl *tstate)
{
_PyType_MergeThreadLocalRefcounts(tstate);
PyMem_Free(tstate->types.refcounts);
tstate->types.refcounts = NULL;
tstate->types.size = 0;
tstate->types.is_finalized = 1;
}
void
_PyType_FinalizeIdPool(PyInterpreterState *interp)
{
struct _Py_type_id_pool *pool = &interp->type_ids;
// First, set the free-list to NULL values
while (pool->freelist) {
_Py_type_id_entry *next = pool->freelist->next;
pool->freelist->type = NULL;
pool->freelist = next;
}
// Now everything non-NULL is a type. Set the type's id to -1 in case it
// outlives the interpreter.
for (Py_ssize_t i = 0; i < pool->size; i++) {
PyHeapTypeObject *ht = pool->table[i].type;
if (ht) {
ht->unique_id = -1;
pool->table[i].type = NULL;
}
}
PyMem_Free(pool->table);
pool->table = NULL;
pool->freelist = NULL;
pool->size = 0;
}
#endif /* Py_GIL_DISABLED */
|
