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
|
/*
Logic for a better replacement of PyGILState_Ensure().
This version is ready to handle the case of a non-Python-started
thread in which we do a large number of calls to CFFI callbacks. If
we were to rely on PyGILState_Ensure() for that, we would constantly
be creating and destroying PyThreadStates---it is slow, and
PyThreadState_Delete() will actually walk the list of all thread
states, making it O(n). :-(
This version only creates one PyThreadState object the first time we
see a given thread, and keep it alive until the thread is really
shut down, using a destructor on the tls key.
*/
#ifndef CFFI_MISC_THREAD_POSIX_H
#define CFFI_MISC_THREAD_POSIX_H
#include <pthread.h>
#include "misc_thread_common.h"
static pthread_key_t cffi_tls_key;
static void init_cffi_tls(void)
{
if (pthread_key_create(&cffi_tls_key, &cffi_thread_shutdown) != 0)
PyErr_SetString(PyExc_OSError, "pthread_key_create() failed");
}
static struct cffi_tls_s *_make_cffi_tls(void)
{
void *p = calloc(1, sizeof(struct cffi_tls_s));
if (p == NULL)
return NULL;
if (pthread_setspecific(cffi_tls_key, p) != 0) {
free(p);
return NULL;
}
return p;
}
static struct cffi_tls_s *get_cffi_tls(void)
{
void *p = pthread_getspecific(cffi_tls_key);
if (p == NULL)
p = _make_cffi_tls();
return (struct cffi_tls_s *)p;
}
#define save_errno save_errno_only
#define restore_errno restore_errno_only
#ifdef Py_GIL_DISABLED
# ifndef __ATOMIC_SEQ_CST
# error "The free threading build needs atomic support"
# endif
/* Minimal atomic support */
static void *cffi_atomic_load(void **ptr)
{
return __atomic_load_n(ptr, __ATOMIC_SEQ_CST);
}
static void cffi_atomic_store(void **ptr, void *value)
{
__atomic_store_n(ptr, value, __ATOMIC_SEQ_CST);
}
static uint8_t cffi_atomic_load_uint8(uint8_t *ptr)
{
return __atomic_load_n(ptr, __ATOMIC_SEQ_CST);
}
static void cffi_atomic_store_uint8(uint8_t *ptr, uint8_t value)
{
__atomic_store_n(ptr, value, __ATOMIC_SEQ_CST);
}
static Py_ssize_t cffi_atomic_load_ssize(Py_ssize_t *ptr)
{
return __atomic_load_n(ptr, __ATOMIC_SEQ_CST);
}
static void cffi_atomic_store_ssize(Py_ssize_t *ptr, Py_ssize_t value)
{
__atomic_store_n(ptr, value, __ATOMIC_SEQ_CST);
}
#endif
#endif /* CFFI_MISC_THREAD_POSIX_H */
|
