mono/utils/lock-free-queue.h

   1 /*
   2  * lock-free-queue.h: Lock free queue.
   3  *
   4  * (C) Copyright 2011 Novell, Inc
   5  *
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining
   8  * a copy of this software and associated documentation files (the
   9  * "Software"), to deal in the Software without restriction, including
  10  * without limitation the rights to use, copy, modify, merge, publish,
  11  * distribute, sublicense, and/or sell copies of the Software, and to
  12  * permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be
  16  * included in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  21  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  22  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27
  28 #ifndef __MONO_LOCKFREEQUEUE_H__
  29 #define __MONO_LOCKFREEQUEUE_H__
  30
  31 #include <glib.h>
  32 #include <mono/utils/mono-publib.h>
  33
  34 //#define QUEUE_DEBUG   1
  35
  36 typedef struct _MonoLockFreeQueueNode MonoLockFreeQueueNode;
  37
  38 struct _MonoLockFreeQueueNode {
  39         MonoLockFreeQueueNode * volatile next;
  40 #ifdef QUEUE_DEBUG
  41         gint32 in_queue;
  42 #endif
  43 };
  44
  45 typedef struct {
  46         MonoLockFreeQueueNode node;
  47         volatile gint32 in_use;
  48 } MonoLockFreeQueueDummy;
  49
  50 #define MONO_LOCK_FREE_QUEUE_NUM_DUMMIES        2
  51
  52 typedef struct {
  53         MonoLockFreeQueueNode * volatile head;
  54         MonoLockFreeQueueNode * volatile tail;
  55         MonoLockFreeQueueDummy dummies [MONO_LOCK_FREE_QUEUE_NUM_DUMMIES];
  56         volatile gint32 has_dummy;
  57 } MonoLockFreeQueue;
  58
  59 MONO_API void mono_lock_free_queue_init (MonoLockFreeQueue *q);
  60
  61 MONO_API void mono_lock_free_queue_node_init (MonoLockFreeQueueNode *node, gboolean poison);
  62 MONO_API void mono_lock_free_queue_node_unpoison (MonoLockFreeQueueNode *node);
  63
  64 MONO_API void mono_lock_free_queue_enqueue (MonoLockFreeQueue *q, MonoLockFreeQueueNode *node);
  65
  66 MONO_API MonoLockFreeQueueNode* mono_lock_free_queue_dequeue (MonoLockFreeQueue *q);
  67
  68 #endif