Subversion Repositories Kolibri OS

Rev

Rev 1892 | Go to most recent revision | Blame | Last modification | View Log | Download | RSS feed

  1. /* cairo - a vector graphics library with display and print output
  2.  *
  3.  * Copyright © 2009 Chris Wilson
  4.  *
  5.  * This library is free software; you can redistribute it and/or
  6.  * modify it either under the terms of the GNU Lesser General Public
  7.  * License version 2.1 as published by the Free Software Foundation
  8.  * (the "LGPL") or, at your option, under the terms of the Mozilla
  9.  * Public License Version 1.1 (the "MPL"). If you do not alter this
  10.  * notice, a recipient may use your version of this file under either
  11.  * the MPL or the LGPL.
  12.  *
  13.  * You should have received a copy of the LGPL along with this library
  14.  * in the file COPYING-LGPL-2.1; if not, write to the Free Software
  15.  * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
  16.  * You should have received a copy of the MPL along with this library
  17.  * in the file COPYING-MPL-1.1
  18.  *
  19.  * The contents of this file are subject to the Mozilla Public License
  20.  * Version 1.1 (the "License"); you may not use this file except in
  21.  * compliance with the License. You may obtain a copy of the License at
  22.  * http://www.mozilla.org/MPL/
  23.  *
  24.  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
  25.  * OF ANY KIND, either express or implied. See the LGPL or the MPL for
  26.  * the specific language governing rights and limitations.
  27.  *
  28.  * The Original Code is the cairo graphics library.
  29.  *
  30.  * The Initial Developer of the Original Code is University of Southern
  31.  * California.
  32.  *
  33.  * Contributor(s):
  34.  *      Chris Wilson <chris@chris-wilson.co.uk>
  35.  */
  36.  
  37. #ifndef CAIRO_FREED_POOL_H
  38. #define CAIRO_FREED_POOL_H
  39.  
  40. #include "cairoint.h"
  41. #include "cairo-atomic-private.h"
  42.  
  43. CAIRO_BEGIN_DECLS
  44.  
  45. #define DISABLE_FREED_POOLS 0
  46.  
  47. #if HAS_ATOMIC_OPS && ! DISABLE_FREED_POOLS
  48. /* Keep a stash of recently freed clip_paths, since we need to
  49.  * reallocate them frequently.
  50.  */
  51. #define MAX_FREED_POOL_SIZE 16
  52. typedef struct {
  53.     void *pool[MAX_FREED_POOL_SIZE];
  54.     int top;
  55. } freed_pool_t;
  56.  
  57. static cairo_always_inline void *
  58. _atomic_fetch (void **slot)
  59. {
  60.     void *ptr;
  61.  
  62.     do {
  63.         ptr = _cairo_atomic_ptr_get (slot);
  64.     } while (! _cairo_atomic_ptr_cmpxchg (slot, ptr, NULL));
  65.  
  66.     return ptr;
  67. }
  68.  
  69. static cairo_always_inline cairo_bool_t
  70. _atomic_store (void **slot, void *ptr)
  71. {
  72.     return _cairo_atomic_ptr_cmpxchg (slot, NULL, ptr);
  73. }
  74.  
  75. cairo_private void *
  76. _freed_pool_get_search (freed_pool_t *pool);
  77.  
  78. static inline void *
  79. _freed_pool_get (freed_pool_t *pool)
  80. {
  81.     void *ptr;
  82.     int i;
  83.  
  84.     i = pool->top - 1;
  85.     if (i < 0)
  86.         i = 0;
  87.  
  88.     ptr = _atomic_fetch (&pool->pool[i]);
  89.     if (likely (ptr != NULL)) {
  90.         pool->top = i;
  91.         return ptr;
  92.     }
  93.  
  94.     /* either empty or contended */
  95.     return _freed_pool_get_search (pool);
  96. }
  97.  
  98. cairo_private void
  99. _freed_pool_put_search (freed_pool_t *pool, void *ptr);
  100.  
  101. static inline void
  102. _freed_pool_put (freed_pool_t *pool, void *ptr)
  103. {
  104.     int i;
  105.  
  106.     i = pool->top;
  107.     if (likely (i < ARRAY_LENGTH (pool->pool) &&
  108.                 _atomic_store (&pool->pool[i], ptr)))
  109.     {
  110.         pool->top = i + 1;
  111.         return;
  112.     }
  113.  
  114.     /* either full or contended */
  115.     _freed_pool_put_search (pool, ptr);
  116. }
  117.  
  118. cairo_private void
  119. _freed_pool_reset (freed_pool_t *pool);
  120.  
  121. #define HAS_FREED_POOL 1
  122.  
  123. #else
  124.  
  125. /* A warning about an unused freed-pool in a build without atomics
  126.  * enabled usually indicates a missing _freed_pool_reset() in the
  127.  * static reset function */
  128.  
  129. typedef int freed_pool_t;
  130.  
  131. #define _freed_pool_get(pool) NULL
  132. #define _freed_pool_put(pool, ptr) free(ptr)
  133. #define _freed_pool_reset(ptr)
  134.  
  135. #endif
  136.  
  137. CAIRO_END_DECLS
  138.  
  139. #endif /* CAIRO_FREED_POOL_PRIVATE_H */
  140.