// XlaHostCompute nodes. Each outside compilation subgraph will be rewritten by
// `RewriteOutsideCompilationSubgraphFn`, and they will be merged into one
// single host side graph (`host_graph`).
//
// xla_cluster_attr_name and outside_compilation_attr_name: attr name for XLA
//   computation and outside compilation. Required for
//   `RewriteOutsideCompilationSubgraphFn`.

  mutex_lock l(mu_);
  return status_;
}

Status QueueRunner::ExportCostGraph(CostGraphDef* cost_graph) const {
  if (!cg_mu_) {
    return Status(absl::StatusCode::kFailedPrecondition,
                  "This QueueRunner doesn't collect a cost graph.");
  }
  mutex_lock l(*cg_mu_);
  cost_graph->MergeFrom(*cost_graph_);
  return absl::OkStatus();
}

  /// otherwise returns the first captured failure status.
  Status Join() final;

  /// Returns the latest status.
  Status GetStatus();

  // Returns the stored cost model.
  Status ExportCostGraph(CostGraphDef* cost_graph) const override;

 private:
  QueueRunner() : coord_(nullptr), stopped_(false), cg_mu_(nullptr) {}

  // Initializes the instance with the QueueRunnerDef proto.
  Status Init(const QueueRunnerDef& queue_runner_def);

#ifndef TENSORFLOW_CC_TRAINING_COORDINATOR_H_
#define TENSORFLOW_CC_TRAINING_COORDINATOR_H_

#include <atomic>
#include <memory>
#include <unordered_set>
#include <vector>

#include "tensorflow/core/framework/cost_graph.pb.h"
#include "tensorflow/core/lib/core/status.h"
#include "tensorflow/core/platform/macros.h"
#include "tensorflow/core/platform/mutex.h"
#include "tensorflow/core/protobuf/config.pb.h"

  mutex_lock l(mu_);
  while (!should_stop_) {
    wait_for_stop_.wait(l);
  }
}

Status Coordinator::ExportCostGraph(CostGraphDef* cost_graph) const {
  mutex_lock l(runners_lock_);
  for (auto& t : runners_) {
    Status s = t->ExportCostGraph(cost_graph);
    if (!s.ok()) {
      return s;
    }
  }
  return absl::OkStatus();
}