fix thread hang bug

mindspore/ccsrc/dataset/engine/datasetops/filter_op.cc

@@ -63,9 +63,10 @@ Status FilterOp::operator()() {
   RETURN_UNEXPECTED_IF_NULL(tree_);
   filter_queues_.Init(num_workers_, oc_queue_size_);
   RETURN_IF_NOT_OK(filter_queues_.Register(tree_->AllTasks()));
-  RETURN_IF_NOT_OK(tree_->LaunchWorkers(num_workers_, std::bind(&FilterOp::WorkerEntry, this, std::placeholders::_1)));
+  Status rc = tree_->LaunchWorkers(num_workers_, std::bind(&FilterOp::WorkerEntry, this, std::placeholders::_1));
   // Synchronize with TaskManager.
   TaskManager::FindMe()->Post();
+  RETURN_IF_NOT_OK(rc);
   RETURN_IF_NOT_OK(Collector());
   return Status::OK();
 }

mindspore/ccsrc/dataset/engine/db_connector.h

@@ -62,7 +62,7 @@ class DbConnector : public Connector<std::unique_ptr<DataBuffer>> {
                     "[ERROR] nullptr detected when getting data from db connector");
     } else {
       std::unique_lock<std::mutex> lk(m_);
-      RETURN_IF_NOT_OK(cv_.Wait(&lk, [this, worker_id]() { return expect_consumer_ == worker_id; }));
+      RETURN_IF_NOT_OK(cv_.Wait(&lk, [this, worker_id]() { return (expect_consumer_ == worker_id) || end_of_file_; }));
       // Once an EOF message is encountered this flag will be set and we can return early.
       if (end_of_file_) {
         *result = std::make_unique<DataBuffer>(0, DataBuffer::kDeBFlagEOF);