Merge pull request #2927 from elsid/work_queue

Use std types for WorkQueue

components/sceneutil/workqueue.cpp

@@ -2,69 +2,55 @@
 
 #include <components/debug/debuglog.hpp>
 
+#include <numeric>
+
 namespace SceneUtil
 {
 
 void WorkItem::waitTillDone()
 {
-    if (mDone > 0)
+    if (mDone)
         return;
 
-    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(mMutex);
-    while (mDone == 0)
+    std::unique_lock<std::mutex> lock(mMutex);
+    while (!mDone)
     {
-        mCondition.wait(&mMutex);
+        mCondition.wait(lock);
     }
 }
 
 void WorkItem::signalDone()
 {
     {
-        OpenThreads::ScopedLock<OpenThreads::Mutex> lock(mMutex);
-        mDone.exchange(1);
+        std::unique_lock<std::mutex> lock(mMutex);
+        mDone = true;
     }
-    mCondition.broadcast();
-}
-
-WorkItem::WorkItem()
-{
-}
-
-WorkItem::~WorkItem()
-{
+    mCondition.notify_all();
 }
 
 bool WorkItem::isDone() const
 {
-    return (mDone > 0);
+    return mDone;
 }
 
 WorkQueue::WorkQueue(int workerThreads)
     : mIsReleased(false)
 {
     for (int i=0; i<workerThreads; ++i)
-    {
-        WorkThread* thread = new WorkThread(this);
-        mThreads.push_back(thread);
-        thread->startThread();
-    }
+        mThreads.emplace_back(std::make_unique<WorkThread>(*this));
 }
 
 WorkQueue::~WorkQueue()
 {
     {
-        OpenThreads::ScopedLock<OpenThreads::Mutex> lock(mMutex);
+        std::unique_lock<std::mutex> lock(mMutex);
         while (!mQueue.empty())
             mQueue.pop_back();
         mIsReleased = true;
-        mCondition.broadcast();
+        mCondition.notify_all();
     }
 
-    for (unsigned int i=0; i<mThreads.size(); ++i)
-    {
-        mThreads[i]->join();
-        delete mThreads[i];
-    }
+    mThreads.clear();
 }
 
 void WorkQueue::addWorkItem(osg::ref_ptr<WorkItem> item, bool front)
@@ -75,20 +61,20 @@ void WorkQueue::addWorkItem(osg::ref_ptr<WorkItem> item, bool front)
         return;
     }
 
-    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(mMutex);
+    std::unique_lock<std::mutex> lock(mMutex);
     if (front)
         mQueue.push_front(item);
     else
         mQueue.push_back(item);
-    mCondition.signal();
+    mCondition.notify_one();
 }
 
 osg::ref_ptr<WorkItem> WorkQueue::removeWorkItem()
 {
-    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(mMutex);
+    std::unique_lock<std::mutex> lock(mMutex);
     while (mQueue.empty() && !mIsReleased)
     {
-        mCondition.wait(&mMutex);
+        mCondition.wait(lock);
     }
     if (!mQueue.empty())
     {
@@ -102,27 +88,28 @@ osg::ref_ptr<WorkItem> WorkQueue::removeWorkItem()
 
 unsigned int WorkQueue::getNumItems() const
 {
-    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(mMutex);
+    std::unique_lock<std::mutex> lock(mMutex);
     return mQueue.size();
 }
 
 unsigned int WorkQueue::getNumActiveThreads() const
 {
-    unsigned int count = 0;
-    for (unsigned int i=0; i<mThreads.size(); ++i)
-    {
-        if (mThreads[i]->isActive())
-            ++count;
-    }
-    return count;
+    return std::accumulate(mThreads.begin(), mThreads.end(), 0u,
+        [] (auto r, const auto& t) { return r + t->isActive(); });
 }
 
-WorkThread::WorkThread(WorkQueue *workQueue)
-    : mWorkQueue(workQueue)
+WorkThread::WorkThread(WorkQueue& workQueue)
+    : mWorkQueue(&workQueue)
     , mActive(false)
+    , mThread([this] { run(); })
 {
 }
 
+WorkThread::~WorkThread()
+{
+    mThread.join();
+}
+
 void WorkThread::run()
 {
     while (true)

components/sceneutil/workqueue.hpp

@@ -1,16 +1,14 @@
 #ifndef OPENMW_COMPONENTS_SCENEUTIL_WORKQUEUE_H
 #define OPENMW_COMPONENTS_SCENEUTIL_WORKQUEUE_H
 
-#include <OpenThreads/Atomic>
-#include <OpenThreads/Mutex>
-#include <OpenThreads/Condition>
-#include <OpenThreads/Thread>
-
 #include <osg/Referenced>
 #include <osg/ref_ptr>
 
 #include <atomic>
 #include <queue>
+#include <thread>
+#include <mutex>
+#include <condition_variable>
 
 namespace SceneUtil
 {
@@ -18,9 +16,6 @@ namespace SceneUtil
     class WorkItem : public osg::Referenced
     {
     public:
-        WorkItem();
-        virtual ~WorkItem();
-
         /// Override in a derived WorkItem to perform actual work.
         virtual void doWork() {}
 
@@ -35,10 +30,10 @@ namespace SceneUtil
         /// Set abort flag in order to return from doWork() as soon as possible. May not be respected by all WorkItems.
         virtual void abort() {}
 
-    protected:
-        OpenThreads::Atomic mDone;
-        OpenThreads::Mutex mMutex;
-        OpenThreads::Condition mCondition;
+    private:
+        std::atomic_bool mDone {false};
+        std::mutex mMutex;
+        std::condition_variable mCondition;
     };
 
     class WorkThread;
@@ -70,25 +65,28 @@ namespace SceneUtil
         bool mIsReleased;
         std::deque<osg::ref_ptr<WorkItem> > mQueue;
 
-        mutable OpenThreads::Mutex mMutex;
-        OpenThreads::Condition mCondition;
+        mutable std::mutex mMutex;
+        std::condition_variable mCondition;
 
-        std::vector<WorkThread*> mThreads;
+        std::vector<std::unique_ptr<WorkThread>> mThreads;
     };
 
     /// Internally used by WorkQueue.
-    class WorkThread : public OpenThreads::Thread
+    class WorkThread
     {
     public:
-        WorkThread(WorkQueue* workQueue);
+        WorkThread(WorkQueue& workQueue);
 
-        virtual void run();
+        ~WorkThread();
 
         bool isActive() const;
 
     private:
         WorkQueue* mWorkQueue;
         std::atomic<bool> mActive;
+        std::thread mThread;
+
+        void run();
     };