Line data    Source code

       1             : /**********************************************************************
       2             :  *
       3             :  * Project:  GDAL
       4             :  * Purpose:  Global thread pool
       5             :  * Author:   Even Rouault, <even dot rouault at spatialys dot com>
       6             :  *
       7             :  **********************************************************************
       8             :  * Copyright (c) 2020, Even Rouault, <even dot rouault at spatialys dot com>
       9             :  *
      10             :  * Permission is hereby granted, free of charge, to any person obtaining a
      11             :  * copy of this software and associated documentation files (the "Software"),
      12             :  * to deal in the Software without restriction, including without limitation
      13             :  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
      14             :  * and/or sell copies of the Software, and to permit persons to whom the
      15             :  * Software is furnished to do so, subject to the following conditions:
      16             :  *
      17             :  * The above copyright notice and this permission notice shall be included
      18             :  * in all copies or substantial portions of the Software.
      19             :  *
      20             :  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
      21             :  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
      22             :  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
      23             :  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
      24             :  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
      25             :  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
      26             :  * DEALINGS IN THE SOFTWARE.
      27             :  ****************************************************************************/
      28             : 
      29             : #include "gdal_thread_pool.h"
      30             : 
      31             : #include <mutex>
      32             : 
      33             : // For unclear reasons, attempts at making this a std::unique_ptr<>, even
      34             : // through a GetCompressThreadPool() method like GetMutexThreadPool(), lead
      35             : // to "ctest -R autotest_alg" (and other autotest components as well)
      36             : // to hang forever once the tests have terminated.
      37             : static CPLWorkerThreadPool *gpoCompressThreadPool = nullptr;
      38             : 
      39         935 : static std::mutex &GetMutexThreadPool()
      40             : {
      41             :     static std::mutex gMutexThreadPool;
      42         935 :     return gMutexThreadPool;
      43             : }
      44             : 
      45          83 : CPLWorkerThreadPool *GDALGetGlobalThreadPool(int nThreads)
      46             : {
      47          83 :     std::lock_guard oGuard(GetMutexThreadPool());
      48          83 :     if (gpoCompressThreadPool == nullptr)
      49             :     {
      50           4 :         gpoCompressThreadPool = new CPLWorkerThreadPool();
      51           4 :         if (!gpoCompressThreadPool->Setup(nThreads, nullptr, nullptr, false))
      52             :         {
      53           0 :             delete gpoCompressThreadPool;
      54           0 :             gpoCompressThreadPool = nullptr;
      55             :         }
      56             :     }
      57          79 :     else if (nThreads > gpoCompressThreadPool->GetThreadCount())
      58             :     {
      59             :         // Increase size of thread pool
      60           1 :         gpoCompressThreadPool->Setup(nThreads, nullptr, nullptr, false);
      61             :     }
      62         166 :     return gpoCompressThreadPool;
      63             : }
      64             : 
      65         852 : void GDALDestroyGlobalThreadPool()
      66             : {
      67         852 :     std::lock_guard oGuard(GetMutexThreadPool());
      68         852 :     delete gpoCompressThreadPool;
      69         852 :     gpoCompressThreadPool = nullptr;
      70         852 : }