parallel for on pthreads initial commit

removing trailing whitespaces

Compilation error on Mac fix & warning on android

Warnings fixed on iOs

CMakeLists.txt

@@ -188,6 +188,7 @@ OCV_OPTION(WITH_QUICKTIME      "Use QuickTime for Video I/O insted of QTKit" OFF
 OCV_OPTION(WITH_TBB            "Include Intel TBB support"                   OFF  IF (NOT IOS AND NOT WINRT) )
 OCV_OPTION(WITH_OPENMP         "Include OpenMP support"                      OFF)
 OCV_OPTION(WITH_CSTRIPES       "Include C= support"                          OFF  IF (WIN32 AND NOT WINRT)  )
+OCV_OPTION(WITH_PTHREADS_PF    "Use pthreads-based parallel_for"             OFF  IF (NOT WIN32) )
 OCV_OPTION(WITH_TIFF           "Include TIFF support"                        ON   IF (NOT IOS) )
 OCV_OPTION(WITH_UNICAP         "Include Unicap support (GPL)"                OFF  IF (UNIX AND NOT APPLE AND NOT ANDROID) )
 OCV_OPTION(WITH_V4L            "Include Video 4 Linux support"               ON   IF (UNIX AND NOT ANDROID) )
@@ -1067,6 +1068,7 @@ status("    Use OpenMP:"     HAVE_OPENMP      THEN YES ELSE NO)
 status("    Use GCD"         HAVE_GCD         THEN YES ELSE NO)
 status("    Use Concurrency" HAVE_CONCURRENCY THEN YES ELSE NO)
 status("    Use C=:"         HAVE_CSTRIPES    THEN YES ELSE NO)
+status("    Use pthreads for parallel for:"   HAVE_PTHREADS_PF THEN YES ELSE NO)
 status("    Use Cuda:"       HAVE_CUDA        THEN "YES (ver ${CUDA_VERSION_STRING})" ELSE NO)
 status("    Use OpenCL:"     HAVE_OPENCL      THEN YES ELSE NO)
 

cmake/OpenCVFindLibsPerf.cmake

@@ -119,3 +119,13 @@ if(WITH_OPENMP)
   endif()
   set(HAVE_OPENMP "${OPENMP_FOUND}")
 endif()
+
+if(UNIX OR ANDROID)
+if(NOT APPLE AND NOT HAVE_TBB AND NOT HAVE_OPENMP)
+  set(HAVE_PTHREADS_PF 1)
+else()
+  set(HAVE_PTHREADS_PF 0)
+endif()
+else()
+  set(HAVE_PTHREADS_PF 0)
+endif()

modules/core/src/parallel.cpp

@@ -125,6 +125,8 @@
 #  define CV_PARALLEL_FRAMEWORK "winrt-concurrency"
 #elif defined HAVE_CONCURRENCY
 #  define CV_PARALLEL_FRAMEWORK "ms-concurrency"
+#elif defined HAVE_PTHREADS
+#  define CV_PARALLEL_FRAMEWORK "pthreads"
 #endif
 
 namespace cv
@@ -298,6 +300,10 @@ void cv::parallel_for_(const cv::Range& range, const cv::ParallelLoopBody& body,
             Concurrency::CurrentScheduler::Detach();
         }
 
+#elif defined HAVE_PTHREADS
+        void parallel_for_pthreads(const Range& range, const ParallelLoopBody& body, double nstripes);
+        parallel_for_pthreads(range, body, nstripes);
+
 #else
 
 #error You have hacked and compiling with unsupported parallel framework
@@ -353,6 +359,12 @@ int cv::getNumThreads(void)
         ? Concurrency::CurrentScheduler::Get()->GetNumberOfVirtualProcessors()
         : pplScheduler->GetNumberOfVirtualProcessors());
 
+#elif defined HAVE_PTHREADS
+
+        size_t parallel_pthreads_get_threads_num();
+
+        return parallel_pthreads_get_threads_num();
+
 #else
 
     return 1;
@@ -410,6 +422,12 @@ void cv::setNumThreads( int threads )
                        Concurrency::MaxConcurrency, threads-1));
     }
 
+#elif defined HAVE_PTHREADS
+
+    void parallel_pthreads_set_threads_num(int num);
+
+    parallel_pthreads_set_threads_num(threads);
+
 #endif
 }
 

modules/core/src/parallel_pthreads.cpp

@@ -0,0 +1,592 @@
+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+//  By downloading, copying, installing or using the software you agree to this license.
+//  If you do not agree to this license, do not download, install,
+//  copy or use the software.
+//
+//
+//                           License Agreement
+//                For Open Source Computer Vision Library
+//
+// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
+// Copyright (C) 2009-2011, Willow Garage Inc., all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+//   * Redistribution's of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//
+//   * Redistribution's in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//
+//   * The name of the copyright holders may not be used to endorse or promote products
+//     derived from this software without specific prior written permission.
+//
+// This software is provided by the copyright holders and contributors "as is" and
+// any express or implied warranties, including, but not limited to, the implied
+// warranties of merchantability and fitness for a particular purpose are disclaimed.
+// In no event shall the Intel Corporation or contributors be liable for any direct,
+// indirect, incidental, special, exemplary, or consequential damages
+// (including, but not limited to, procurement of substitute goods or services;
+// loss of use, data, or profits; or business interruption) however caused
+// and on any theory of liability, whether in contract, strict liability,
+// or tort (including negligence or otherwise) arising in any way out of
+// the use of this software, even if advised of the possibility of such damage.
+//
+//M*/
+
+#include "precomp.hpp"
+
+#if defined HAVE_PTHREADS && HAVE_PTHREADS
+
+#include <algorithm>
+#include <pthread.h>
+
+namespace cv
+{
+
+class ThreadManager;
+
+enum ForThreadState
+{
+    eFTNotStarted = 0,
+    eFTStarted = 1,
+    eFTToStop = 2,
+    eFTStoped = 3
+};
+
+enum ThreadManagerPoolState
+{
+    eTMNotInited = 0,
+    eTMFailedToInit = 1,
+    eTMInited = 2,
+    eTMSingleThreaded = 3
+};
+
+struct work_load
+{
+    work_load()
+    {
+        clear();
+    }
+
+    work_load(const cv::Range& range, const cv::ParallelLoopBody& body, int nstripes)
+    {
+        set(range, body, nstripes);
+    }
+
+    void set(const cv::Range& range, const cv::ParallelLoopBody& body, int nstripes)
+    {
+        m_body = &body;
+        m_range = &range;
+        m_nstripes = nstripes;
+        m_blocks_count = ((m_range->end - m_range->start - 1)/m_nstripes) + 1;
+    }
+
+    const cv::ParallelLoopBody* m_body;
+    const cv::Range*            m_range;
+    int                         m_nstripes;
+    unsigned int                m_blocks_count;
+
+    void clear()
+    {
+        m_body = 0;
+        m_range = 0;
+        m_nstripes = 0;
+        m_blocks_count = 0;
+    }
+};
+
+class ForThread
+{
+public:
+
+    ForThread(): m_task_start(false), m_parent(0), m_state(eFTNotStarted), m_id(0)
+    {
+    }
+
+    //called from manager thread
+    bool init(size_t id, ThreadManager* parent);
+
+    //called from manager thread
+    void run();
+
+    //called from manager thread
+    void stop();
+
+    ~ForThread();
+
+private:
+
+    //called from worker thread
+    static void* thread_loop_wrapper(void* thread_object);
+
+    //called from worker thread
+    void execute();
+
+    //called from worker thread
+    void thread_body();
+
+    pthread_t       m_posix_thread;
+    pthread_mutex_t m_thread_mutex;
+    pthread_cond_t  m_cond_thread_task;
+    bool            m_task_start;
+
+    ThreadManager*  m_parent;
+    ForThreadState  m_state;
+    size_t          m_id;
+};
+
+class ThreadManager
+{
+public:
+    friend class ForThread;
+
+    static ThreadManager& instance()
+    {
+        if(!m_instance.ptr)
+        {
+            pthread_mutex_lock(&m_manager_access_mutex);
+
+            if(!m_instance.ptr)
+            {
+                m_instance.ptr = new ThreadManager();
+            }
+
+            pthread_mutex_unlock(&m_manager_access_mutex);
+        }
+
+        return *m_instance.ptr;
+    }
+
+
+    static void stop()
+    {
+        ThreadManager& manager = instance();
+
+        if(manager.m_pool_state == eTMInited)
+        {
+            for(size_t i = 0; i < manager.m_num_threads; ++i)
+            {
+                manager.m_threads[i].stop();
+            }
+        }
+
+        manager.m_pool_state = eTMNotInited;
+    }
+
+    void run(const cv::Range& range, const cv::ParallelLoopBody& body, double nstripes);
+
+    size_t getNumOfThreads();
+
+    void setNumOfThreads(size_t n);
+
+private:
+
+    struct ptr_holder
+    {
+        ThreadManager* ptr;
+
+        ptr_holder(): ptr(NULL) { }
+
+        ~ptr_holder()
+        {
+            if(ptr)
+            {
+                delete ptr;
+            }
+        }
+    };
+
+    ThreadManager();
+
+    ~ThreadManager();
+
+    void wait_complete();
+
+    void notify_complete();
+
+    bool initPool();
+
+    size_t defaultNumberOfThreads();
+
+    std::vector<ForThread> m_threads;
+    size_t m_num_threads;
+
+    pthread_mutex_t m_manager_task_mutex;
+    pthread_cond_t  m_cond_thread_task_complete;
+    bool            m_task_complete;
+
+    unsigned int m_task_position;
+    unsigned int m_num_of_completed_tasks;
+
+    static pthread_mutex_t m_manager_access_mutex;
+    static ptr_holder m_instance;
+
+    static const char m_env_name[];
+    static const unsigned int m_default_number_of_threads;
+
+    work_load m_work_load;
+
+    struct work_thread_t
+    {
+        work_thread_t(): value(false) { }
+        bool value;
+    };
+
+    cv::TLSData<work_thread_t> m_is_work_thread;
+
+    ThreadManagerPoolState m_pool_state;
+};
+
+#ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
+#define PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP PTHREAD_RECURSIVE_MUTEX_INITIALIZER
+#endif
+
+pthread_mutex_t ThreadManager::m_manager_access_mutex = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
+
+ThreadManager::ptr_holder ThreadManager::m_instance;
+const char ThreadManager::m_env_name[] = "OPENCV_FOR_THREADS_NUM";
+const unsigned int ThreadManager::m_default_number_of_threads = 8;
+
+ForThread::~ForThread()
+{
+    if(m_state == eFTStarted)
+    {
+        stop();
+
+        pthread_mutex_destroy(&m_thread_mutex);
+
+        pthread_cond_destroy(&m_cond_thread_task);
+    }
+}
+
+bool ForThread::init(size_t id, ThreadManager* parent)
+{
+    m_id = id;
+
+    m_parent = parent;
+
+    int res = 0;
+
+    res |= pthread_mutex_init(&m_thread_mutex, NULL);
+
+    res |= pthread_cond_init(&m_cond_thread_task, NULL);
+
+    if(!res)
+    {
+        res = pthread_create(&m_posix_thread, NULL, thread_loop_wrapper, (void*)this);
+    }
+
+
+    return res == 0;
+}
+
+void ForThread::stop()
+{
+    if(m_state == eFTStarted)
+    {
+        m_state = eFTToStop;
+
+        run();
+
+        pthread_join(m_posix_thread, NULL);
+    }
+
+    m_state = eFTStoped;
+}
+
+void ForThread::run()
+{
+    pthread_mutex_lock(&m_thread_mutex);
+
+    m_task_start = true;
+
+    pthread_cond_signal(&m_cond_thread_task);
+
+    pthread_mutex_unlock(&m_thread_mutex);
+}
+
+void* ForThread::thread_loop_wrapper(void* thread_object)
+{
+    ((ForThread*)thread_object)->thread_body();
+    return 0;
+}
+
+void ForThread::execute()
+{
+    unsigned int m_current_pos = CV_XADD(&m_parent->m_task_position, 1);
+
+    work_load& load = m_parent->m_work_load;
+
+    while(m_current_pos < load.m_blocks_count)
+    {
+        int start = load.m_range->start + m_current_pos*load.m_nstripes;
+        int end = std::min(start + load.m_nstripes, load.m_range->end);
+
+        load.m_body->operator()(cv::Range(start, end));
+
+        m_current_pos = CV_XADD(&m_parent->m_task_position, 1);
+    }
+}
+
+void ForThread::thread_body()
+{
+    m_parent->m_is_work_thread.get()->value = true;
+
+    pthread_mutex_lock(&m_thread_mutex);
+
+    m_state = eFTStarted;
+
+    while(m_state == eFTStarted)
+    {
+        //to handle spurious wakeups
+        while( !m_task_start && m_state != eFTToStop )
+            pthread_cond_wait(&m_cond_thread_task, &m_thread_mutex);
+
+        if(m_state == eFTStarted)
+        {
+            execute();
+
+            m_task_start = false;
+
+            m_parent->notify_complete();
+        }
+    }
+
+    pthread_mutex_unlock(&m_thread_mutex);
+}
+
+ThreadManager::ThreadManager(): m_num_threads(0), m_task_complete(false), m_num_of_completed_tasks(0), m_pool_state(eTMNotInited)
+{
+    int res = 0;
+
+    res |= pthread_mutex_init(&m_manager_task_mutex, NULL);
+
+    res |= pthread_cond_init(&m_cond_thread_task_complete, NULL);
+
+    if(!res)
+    {
+        setNumOfThreads(defaultNumberOfThreads());
+
+        m_task_position = 0;
+    }
+    else
+    {
+        m_num_threads = 1;
+        m_pool_state = eTMFailedToInit;
+        m_task_position = 0;
+
+        //print error;
+    }
+}
+
+ThreadManager::~ThreadManager()
+{
+    stop();
+
+    pthread_mutex_destroy(&m_manager_task_mutex);
+
+    pthread_cond_destroy(&m_cond_thread_task_complete);
+
+    pthread_mutex_destroy(&m_manager_access_mutex);
+}
+
+void ThreadManager::run(const cv::Range& range, const cv::ParallelLoopBody& body, double nstripes)
+{
+    bool is_work_thread;
+
+    is_work_thread = m_is_work_thread.get()->value;
+
+    if( (getNumOfThreads() > 1) && !is_work_thread && (range.end - range.start > 1) )
+    {
+        int res = pthread_mutex_trylock(&m_manager_access_mutex);
+
+        if(!res)
+        {
+            if(initPool())
+            {
+                double min_stripes = double(range.end - range.start)/(4*m_threads.size());
+
+                nstripes = std::max(nstripes, min_stripes);
+
+                pthread_mutex_lock(&m_manager_task_mutex);
+
+                m_num_of_completed_tasks = 0;
+
+                m_task_position = 0;
+
+                m_task_complete = false;
+
+                m_work_load.set(range, body, std::ceil(nstripes));
+
+                for(size_t i = 0; i < m_threads.size(); ++i)
+                {
+                    m_threads[i].run();
+                }
+
+                wait_complete();
+            }
+            else
+            {
+                //print error
+                body(range);
+            }
+        }
+        else
+        {
+            body(range);
+        }
+    }
+    else
+    {
+        body(range);
+    }
+}
+
+void ThreadManager::wait_complete()
+{
+    //to handle spurious wakeups
+    while(!m_task_complete)
+        pthread_cond_wait(&m_cond_thread_task_complete, &m_manager_task_mutex);
+
+    pthread_mutex_unlock(&m_manager_task_mutex);
+
+    pthread_mutex_unlock(&m_manager_access_mutex);
+}
+
+void ThreadManager::notify_complete()
+{
+
+    unsigned int comp = CV_XADD(&m_num_of_completed_tasks, 1);
+
+    if(comp == (m_num_threads - 1))
+    {
+        pthread_mutex_lock(&m_manager_task_mutex);
+
+        m_task_complete = true;
+
+        pthread_cond_signal(&m_cond_thread_task_complete);
+
+        pthread_mutex_unlock(&m_manager_task_mutex);
+    }
+}
+
+bool ThreadManager::initPool()
+{
+    if(m_pool_state != eTMNotInited || m_num_threads == 1)
+        return true;
+
+    m_threads.resize(m_num_threads);
+
+    bool res = true;
+
+    for(size_t i = 0; i < m_threads.size(); ++i)
+    {
+        res |= m_threads[i].init(i, this);
+    }
+
+    if(res)
+    {
+        m_pool_state = eTMInited;
+    }
+    else
+    {
+        //TODO: join threads?
+        m_pool_state = eTMFailedToInit;
+    }
+
+    return res;
+}
+
+size_t ThreadManager::getNumOfThreads()
+{
+    return m_num_threads;
+}
+
+void ThreadManager::setNumOfThreads(size_t n)
+{
+    int res = pthread_mutex_lock(&m_manager_access_mutex);
+
+    if(!res)
+    {
+        if(n == 0)
+        {
+            n = defaultNumberOfThreads();
+        }
+
+        if(n != m_num_threads && m_pool_state != eTMFailedToInit)
+        {
+            if(m_pool_state == eTMInited)
+            {
+                stop();
+                m_threads.clear();
+            }
+
+            m_num_threads = n;
+
+            if(m_num_threads == 1)
+            {
+                m_pool_state = eTMSingleThreaded;
+            }
+            else
+            {
+                m_pool_state = eTMNotInited;
+            }
+        }
+
+        pthread_mutex_unlock(&m_manager_access_mutex);
+    }
+}
+
+size_t ThreadManager::defaultNumberOfThreads()
+{
+    unsigned int result = m_default_number_of_threads;
+
+    char * env = getenv(m_env_name);
+
+    if(env != NULL)
+    {
+        sscanf(env, "%u", &result);
+
+        result = std::max(1u, result);
+        //do we need upper limit of threads number?
+    }
+
+    return result;
+}
+
+void parallel_for_pthreads(const cv::Range& range, const cv::ParallelLoopBody& body, double nstripes);
+size_t parallel_pthreads_get_threads_num();
+void parallel_pthreads_set_threads_num(int num);
+
+size_t parallel_pthreads_get_threads_num()
+{
+    return ThreadManager::instance().getNumOfThreads();
+}
+
+void parallel_pthreads_set_threads_num(int num)
+{
+    if(num < 0)
+    {
+        ThreadManager::instance().setNumOfThreads(0);
+    }
+    else
+    {
+        ThreadManager::instance().setNumOfThreads(size_t(num));
+    }
+}
+
+void parallel_for_pthreads(const cv::Range& range, const cv::ParallelLoopBody& body, double nstripes)
+{
+    ThreadManager::instance().run(range, body, nstripes);
+}
+
+}
+
+#endif

modules/core/src/precomp.hpp

@@ -292,6 +292,12 @@ TLSData<CoreTLSData>& getCoreTlsData();
 #define CL_RUNTIME_EXPORT
 #endif
 
+#ifndef HAVE_PTHREADS
+#if !(defined WIN32 || defined _WIN32 || defined WINCE || defined HAVE_WINRT)
+#define HAVE_PTHREADS 1
+#endif
+#endif
+
 extern bool __termination; // skip some cleanups, because process is terminating
                            // (for example, if ExitProcess() was already called)