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
|
/* cairo - a vector graphics library with display and print output
*
* Copyright © 2009 Chris Wilson
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* The Initial Developer of the Original Code is University of Southern
* California.
*
* Contributor(s):
* Chris Wilson <chris@chris-wilson.co.uk>
*/
#ifndef CAIRO_FREED_POOL_H
#define CAIRO_FREED_POOL_H
#include "cairoint.h"
#include "cairo-atomic-private.h"
#if HAS_ATOMIC_OPS
/* Keep a stash of recently freed clip_paths, since we need to
* reallocate them frequently.
*/
#define MAX_FREED_POOL_SIZE 4
typedef struct {
void *pool[MAX_FREED_POOL_SIZE];
int top;
} freed_pool_t;
static cairo_always_inline void *
_atomic_fetch (void **slot)
{
void *ptr;
do {
ptr = _cairo_atomic_ptr_get (slot);
} while (! _cairo_atomic_ptr_cmpxchg (slot, ptr, NULL));
return ptr;
}
static cairo_always_inline cairo_bool_t
_atomic_store (void **slot, void *ptr)
{
return _cairo_atomic_ptr_cmpxchg (slot, NULL, ptr);
}
cairo_private void *
_freed_pool_get_search (freed_pool_t *pool);
static inline void *
_freed_pool_get (freed_pool_t *pool)
{
void *ptr;
int i;
i = pool->top - 1;
if (i < 0)
i = 0;
ptr = _atomic_fetch (&pool->pool[i]);
if (likely (ptr != NULL)) {
pool->top = i;
return ptr;
}
/* either empty or contended */
return _freed_pool_get_search (pool);
}
cairo_private void
_freed_pool_put_search (freed_pool_t *pool, void *ptr);
static inline void
_freed_pool_put (freed_pool_t *pool, void *ptr)
{
int i;
i = pool->top;
if (likely (i < ARRAY_LENGTH (pool->pool) &&
_atomic_store (&pool->pool[i], ptr)))
{
pool->top = i + 1;
return;
}
/* either full or contended */
_freed_pool_put_search (pool, ptr);
}
cairo_private void
_freed_pool_reset (freed_pool_t *pool);
#define HAS_FREED_POOL 1
#else
typedef int freed_pool_t;
#define _freed_pool_get(pool) NULL
#define _freed_pool_put(pool, ptr) free(ptr)
#define _freed_pool_reset(ptr)
#endif
#endif /* CAIRO_FREED_POOL_PRIVATE_H */
|