// nodes in parallel.
// in_flight_nodes_limit: when is_async is true, this value controls the
// maximum number of in flight async nodes. Enqueuing of additional async ops
// after the limit is reached blocks until some inflight nodes finishes.
// The effect is bounding the memory held by inflight TensorHandles that are
// referenced by the inflight nodes.
// A recommended value has not been established.

  ~TF_Operation() = default;
};

struct TF_Session {
  TF_Session(tensorflow::Session* s, TF_Graph* g);

  tensorflow::Session* session;
  TF_Graph* const graph;

  tensorflow::mutex mu TF_ACQUIRED_AFTER(TF_Graph::mu);
  int last_num_graph_nodes;

  // If true, TF_SessionRun and similar methods will call
  // ExtendSessionGraphHelper before running the graph (this is the default

  /// be accessed while holding the Block's mu lock. The data vector should only
  /// be accessed after state == FINISHED, and it should never be modified.
  ///
  /// In order to prevent deadlocks, never grab the block-cache-wide mu_ lock
  /// AFTER grabbing any block's mu lock. It is safe to grab mu without locking
  /// mu_.
  struct Block {
    /// The block data.

  /// and fix this.
  ///
  /// TODO(b/139060984): After all filesystems are converted, revisit note.
  ///
  /// This operation must be provided. See "REQUIRED OPERATIONS" above.
  void (*cleanup)(TF_Filesystem* filesystem);

  /// Creates a new random access read-only file from given `path`.
  ///
  /// After this call `file` may be concurrently accessed by multiple threads.
  ///
  /// Plugins:

                              TracingTensorHandle**) = 0;

  // Finalize this context and make a function out of it. The context is in a
  // invalid state after this call and must be destroyed.
  virtual Status Finalize(OutputList* outputs, AbstractFunction**) = 0;

  // For LLVM style RTTI.
  static bool classof(const AbstractContext* ptr) {

 public:
  using GradientTape<AbstractTensorHandle, GradientFunction,
                     TapeTensor>::GradientTape;
  // Returns whether the tape is persistent, i.e., whether the tape will hold
  // onto its internal state after a call to `ComputeGradient`.
  using GradientTape<AbstractTensorHandle, GradientFunction,
                     TapeTensor>::IsPersistent;

  // Adds this tensor to the list of watched tensors.
  //

TF_CAPI_EXPORT extern void TF_CreateAndSetPjRtCApiClient(
    const char* device_type, TF_Status* status, PJRT_NamedValue* create_options,
    int num_options);

// Resets the PjRt client for a device. After this, `TF_GetPjRtCClient` will
// returns an error for that device.
TF_CAPI_EXPORT extern void TF_ResetPjRtCClient(const char* device_type,
                                               TF_Status* status);

/// classes here are experimental and subject to breaking changes.
/// For documentation on these methods, consult `core/platform/filesystem.h`.

namespace tensorflow {

// TODO(b/143949615): After all filesystems are converted, this file will be
// moved to core/platform, and this class can become a singleton and replace the
// need for `Env::Default()`. At that time, we might decide to remove the need

  //===--------------------------------------------------------------------===//
  // Following are features in current TF Eager Runtime.
  // TODO(tfrt-devs): Figure out a way to deprecate following features after
  // migrated to TFRT.
  //===--------------------------------------------------------------------===//
  // Clear pending nodes in thread executors and kernel caches.
  virtual void ClearCachesAndThreadExecutors() = 0;