Fix GPU mining in ethminer.

libethcore/Ethash.cpp

@@ -300,6 +300,7 @@ void Ethash::GPUMiner::workLoop()
 	// take local copy of work since it may end up being overwritten by kickOff/pause.
 	try {
 		WorkPackage w = work();
+		cnote << "workLoop" << !!m_miner << m_minerSeed << w.seedHash;
 		if (!m_miner || m_minerSeed != w.seedHash)
 		{
 			m_minerSeed = w.seedHash;
@@ -309,7 +310,12 @@ void Ethash::GPUMiner::workLoop()
 
 			unsigned device = instances() > 1 ? index() : s_deviceId;
 
-			if (!EthashAux::computeFull(EthashAux::number(w.seedHash)))
+			while (EthashAux::computeFull(EthashAux::number(w.seedHash)) != 100 && !shouldStop())
+			{
+				cnote << "Awaiting DAG" << EthashAux::computeFull(EthashAux::number(w.seedHash));
+				this_thread::sleep_for(chrono::milliseconds(500));
+			}
+			if (shouldStop())
 				return;
 			EthashAux::FullType dag = EthashAux::full(EthashAux::number(w.seedHash));
 			bytesConstRef dagData = dag->data();

libethcore/EthashAux.cpp

@@ -170,7 +170,9 @@ EthashAux::FullType EthashAux::full(uint64_t _blockNumber, function<int(unsigned
 		}
 
 	s_dagCallback = _f;
+	cnote << "Loading from libethash...";
 	ret = make_shared<FullAllocation>(l->light, dagCallbackShim);
+	cnote << "Done loading.";
 
 	DEV_GUARDED(get()->x_fulls)
 		get()->m_fulls[seedHash] = get()->m_lastUsedFull = ret;
@@ -192,7 +194,9 @@ unsigned EthashAux::computeFull(uint64_t _blockNumber)
 		get()->m_fullProgress = 0;
 		get()->m_generatingFullNumber = _blockNumber / ETHASH_EPOCH_LENGTH * ETHASH_EPOCH_LENGTH;
 		get()->m_fullGenerator = unique_ptr<thread>(new thread([=](){
+			cnote << "Loading full DAG of" << _blockNumber;
 			get()->full(_blockNumber, [](unsigned p){ get()->m_fullProgress = p; return 0; });
+			cnote << "Full DAG loaded";
 			get()->m_fullProgress = 0;
 			get()->m_generatingFullNumber = NotGenerating;
 		}));