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cpl_worker_thread_pool.h
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1/**********************************************************************
2 * $Id$
3 *
4 * Project: CPL - Common Portability Library
5 * Purpose: CPL worker thread pool
6 * Author: Even Rouault, <even dot rouault at spatialys dot com>
7 *
8 **********************************************************************
9 * Copyright (c) 2015, Even Rouault, <even dot rouault at spatialys dot com>
10 *
11 * Permission is hereby granted, free of charge, to any person obtaining a
12 * copy of this software and associated documentation files (the "Software"),
13 * to deal in the Software without restriction, including without limitation
14 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
15 * and/or sell copies of the Software, and to permit persons to whom the
16 * Software is furnished to do so, subject to the following conditions:
17 *
18 * The above copyright notice and this permission notice shall be included
19 * in all copies or substantial portions of the Software.
20 *
21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
22 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
24 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
25 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
26 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
27 * DEALINGS IN THE SOFTWARE.
28 ****************************************************************************/
29
30#ifndef CPL_WORKER_THREAD_POOL_H_INCLUDED_
31#define CPL_WORKER_THREAD_POOL_H_INCLUDED_
32
33#include "cpl_multiproc.h"
34#include "cpl_list.h"
35
36#include <condition_variable>
37#include <memory>
38#include <mutex>
39#include <vector>
40
48#ifndef DOXYGEN_SKIP
49 struct CPLWorkerThreadJob;
50 class CPLWorkerThreadPool;
51
52 struct CPLWorkerThread
53{
54 CPL_DISALLOW_COPY_ASSIGN(CPLWorkerThread)
55 CPLWorkerThread() = default;
56
57 CPLThreadFunc pfnInitFunc = nullptr;
58 void *pInitData = nullptr;
59 CPLWorkerThreadPool *poTP = nullptr;
60 CPLJoinableThread *hThread = nullptr;
61 bool bMarkedAsWaiting = false;
62
63 std::mutex m_mutex{};
64 std::condition_variable m_cv{};
65};
66
67 typedef enum
68{
69 CPLWTS_OK,
70 CPLWTS_STOP,
71 CPLWTS_ERROR
72} CPLWorkerThreadState;
73#endif // ndef DOXYGEN_SKIP
74
75 class CPLJobQueue;
76
78 class CPL_DLL CPLWorkerThreadPool
79{
80 CPL_DISALLOW_COPY_ASSIGN(CPLWorkerThreadPool)
81
82 std::vector<std::unique_ptr<CPLWorkerThread>> aWT{};
83 std::mutex m_mutex{};
84 std::condition_variable m_cv{};
85 volatile CPLWorkerThreadState eState = CPLWTS_OK;
86 CPLList *psJobQueue = nullptr;
87 int nPendingJobs = 0;
88
89 CPLList *psWaitingWorkerThreadsList = nullptr;
90 int nWaitingWorkerThreads = 0;
91
92 int m_nMaxThreads = 0;
93
94 static void WorkerThreadFunction(void *user_data);
95
96 void DeclareJobFinished();
97 CPLWorkerThreadJob *GetNextJob(CPLWorkerThread *psWorkerThread);
98
99 public:
100 CPLWorkerThreadPool();
101 ~CPLWorkerThreadPool();
102
103 bool Setup(int nThreads, CPLThreadFunc pfnInitFunc, void **pasInitData);
104 bool Setup(int nThreads, CPLThreadFunc pfnInitFunc, void **pasInitData,
105 bool bWaitallStarted);
106
107 std::unique_ptr<CPLJobQueue> CreateJobQueue();
108
109 bool SubmitJob(CPLThreadFunc pfnFunc, void *pData);
110 bool SubmitJobs(CPLThreadFunc pfnFunc, const std::vector<void *> &apData);
111 void WaitCompletion(int nMaxRemainingJobs = 0);
112 void WaitEvent();
113
115 int GetThreadCount() const
116 {
117 return m_nMaxThreads;
118 }
119};
120
122 class CPL_DLL CPLJobQueue
123{
124 CPL_DISALLOW_COPY_ASSIGN(CPLJobQueue)
125 CPLWorkerThreadPool *m_poPool = nullptr;
126 std::mutex m_mutex{};
127 std::condition_variable m_cv{};
128 int m_nPendingJobs = 0;
129
130 static void JobQueueFunction(void *);
131 void DeclareJobFinished();
132
134 protected:
135 friend class CPLWorkerThreadPool;
136 explicit CPLJobQueue(CPLWorkerThreadPool *poPool);
138
139 public:
140 ~CPLJobQueue();
141
143 CPLWorkerThreadPool *GetPool()
144 {
145 return m_poPool;
146 }
147
148 bool SubmitJob(CPLThreadFunc pfnFunc, void *pData);
149 void WaitCompletion(int nMaxRemainingJobs = 0);
150};
151
152#endif // CPL_WORKER_THREAD_POOL_H_INCLUDED_
CPLJobQueue
Job queue.
Definition cpl_worker_thread_pool.h:123
CPLJobQueue::GetPool
CPLWorkerThreadPool * GetPool()
Return the owning worker thread pool.
Definition cpl_worker_thread_pool.h:143
CPLWorkerThreadPool
Pool of worker threads.
Definition cpl_worker_thread_pool.h:79
CPLWorkerThreadPool::GetThreadCount
int GetThreadCount() const
Return the number of threads setup.
Definition cpl_worker_thread_pool.h:115
cpl_list.h
Simplest list implementation.
CPL_DISALLOW_COPY_ASSIGN
#define CPL_DISALLOW_COPY_ASSIGN(ClassName)
Helper to remove the copy and assignment constructors so that the compiler will not generate the defa...
Definition cpl_port.h:1042
_CPLList
List element structure.
Definition cpl_list.h:52