AbstractCodec use fair_queue

src/remote/codec.cpp

@@ -53,7 +53,7 @@ namespace epics {
     //PROTECTED
     _readMode(NORMAL), _version(0), _flags(0), _command(0), _payloadSize(0),
       _remoteTransportSocketReceiveBufferSize(MAX_TCP_RECV), _totalBytesSent(0),
-      _blockingProcessQueue(false), _senderThread(0),
+      _senderThread(0),
       _writeMode(PROCESS_SEND_QUEUE),
       _writeOpReady(false),_lowLatency(false),
       _socketBuffer(receiveBuffer),
@@ -98,7 +98,6 @@ namespace epics {
       _maxSendPayloadSize = 
         _sendBuffer->getSize() - 2*PVA_MESSAGE_HEADER_SIZE;	
       _socketSendBufferSize = socketSendBufferSize;
-      _blockingProcessQueue = blockingProcessQueue;
     }
 
 
@@ -851,7 +850,8 @@ namespace epics {
         std::size_t senderProcessed = 0;
         while (senderProcessed++ < MAX_MESSAGE_SEND)
         {
-          TransportSender::shared_pointer sender = _sendQueue.take(-1);
+          TransportSender::shared_pointer sender;
+          _sendQueue.pop_front_try(sender);
           if (sender.get() == 0)
           {
             // flush
@@ -860,19 +860,20 @@ namespace epics {
 
             sendCompleted();	// do not schedule sending
 
-            if (_blockingProcessQueue) {
-              if (terminated())			// termination
+            if (terminated())			// termination
                 break;
-              sender = _sendQueue.take(0);
-              // termination (we want to process even if shutdown)
-              if (sender.get() == 0)		
-                break;
-            }
-            else
-              return;
+            // termination (we want to process even if shutdown)
+            _sendQueue.pop_front(sender);
           }
 
-          processSender(sender);
+          try{
+              processSender(sender);
+          }catch(...){
+              if (_sendBuffer->getPosition() > 0)
+                flush(true);
+              sendCompleted();
+              throw;
+          }
         }
       }
 
@@ -884,13 +885,13 @@ namespace epics {
 
     void AbstractCodec::clearSendQueue()
     {
-      _sendQueue.clean();
+      _sendQueue.clear();
     }
 
 
     void AbstractCodec::enqueueSendRequest(
       TransportSender::shared_pointer const & sender) {
-        _sendQueue.put(sender);
+        _sendQueue.push_back(sender);
         scheduleSend();
     }
 
@@ -1066,8 +1067,6 @@ namespace epics {
         // this is important to avoid cyclic refs (memory leak)
         clearSendQueue();
 
-        _sendQueue.wakeup();
-
         // post close
         internalPostClose(true);
       }

src/remote/codec.h

@@ -112,120 +112,6 @@ namespace epics {
 #endif
 
 
-    // TODO replace this queue with lock-free implementation
-    template<typename T> 
-    class queue {
-    public:
-
-      queue(void) { }
-      //TODO 
-      /*queue(queue const &T) = delete;
-      queue(queue &&T) = delete;
-      queue& operator=(const queue &T) = delete;
-      */
-      ~queue(void) 
-      {    
-      }
-
-
-      bool empty(void) 
-      { 
-        epics::pvData::Lock lock(_queueMutex);
-        return _queue.empty();
-      }
-
-      void clean()
-      { 
-        epics::pvData::Lock lock(_queueMutex);
-        _queue.clear();
-      }
-
-
-      void wakeup() 
-      { 
-        if (!_wakeup.getAndSet(true))
-        {
-          _queueEvent.signal();
-        }
-      }
-
-
-      void put(T const & elem) 
-      { 
-        {
-          epics::pvData::Lock lock(_queueMutex);
-          _queue.push_back(elem);
-        }
-
-        _queueEvent.signal();
-      }
-
-
-      // TODO very sub-optimal (locks and empty() - pop() sequence; at least 2 locks!)
-      T take(int timeOut) 
-      { 
-        while (true)
-        {
-
-          bool isEmpty = empty();
-
-          if (isEmpty)
-          {
-
-            if (timeOut < 0) {
-              return T();
-            }
-
-            while (isEmpty)
-            {
-
-              if (timeOut == 0) {
-                _queueEvent.wait();
-              }
-              else {
-                _queueEvent.wait(timeOut);
-              }
-
-              isEmpty = empty();
-              if (isEmpty)
-              {
-                if (timeOut > 0) {	// TODO spurious wakeup, but not critical
-                  return T();
-                }
-                else // if (timeout == 0)	cannot be negative
-                {
-                  if (_wakeup.getAndSet(false)) {
-                    return T();
-                  }
-                }
-              }
-            }
-          }
-          else
-          {
-            epics::pvData::Lock lock(_queueMutex);
-            if (_queue.empty())
-                return T();
-            T sender = _queue.front();
-            _queue.pop_front();
-            return sender;
-          }
-        }
-      }
-
-      size_t size() {
-          epics::pvData::Lock lock(_queueMutex);
-          return _queue.size();
-      }
-
-    private:
-
-      std::deque<T> _queue;
-      epics::pvData::Event _queueEvent;
-      epics::pvData::Mutex _queueMutex;
-      AtomicValue<bool> _wakeup;
-    };
-
 
     class epicsShareClass io_exception: public std::runtime_error {
     public:
@@ -327,6 +213,10 @@ namespace epics {
         char* /*deserializeTo*/,
         std::size_t /*elementCount*/, std::size_t /*elementSize*/);
 
+      bool sendQueueEmpty() const {
+          return _sendQueue.empty();
+      }
+
     protected:
 
       virtual void sendBufferFull(int tries) = 0;
@@ -341,7 +231,6 @@ namespace epics {
       int32_t _payloadSize; // TODO why not size_t?
       epics::pvData::int32 _remoteTransportSocketReceiveBufferSize;
       int64_t _totalBytesSent;
-      bool _blockingProcessQueue;
       //TODO initialize union
       osiSockAddr _sendTo;
       epicsThreadId _senderThread;
@@ -352,7 +241,7 @@ namespace epics {
       std::tr1::shared_ptr<epics::pvData::ByteBuffer> _socketBuffer;
       std::tr1::shared_ptr<epics::pvData::ByteBuffer> _sendBuffer;
 
-      queue<TransportSender::shared_pointer> _sendQueue;
+      fair_queue<TransportSender> _sendQueue;
 
     private:
 

src/remote/remote.h

@@ -24,6 +24,7 @@
 #include <pv/timer.h>
 #include <pv/pvData.h>
 #include <pv/sharedPtr.h>
+#include <pv/fairQueue.h>
 
 #ifdef remoteEpicsExportSharedSymbols
 #   define epicsExportSharedSymbols
@@ -142,7 +143,7 @@ namespace epics {
         /**
          * Interface defining transport sender (instance sending data over transport).
          */
-        class TransportSender : public Lockable {
+        class TransportSender : public Lockable, public fair_queue<TransportSender>::entry {
         public:
         	POINTER_DEFINITIONS(TransportSender);