message: [tf.data] Adding TraceMe metadata for the `Model` transformation.
diff: @@ -25,6 +25,7 @@ limitations under the License.
  #include "tensorflow/core/framework/tensor.h"
  #include "tensorflow/core/lib/random/random.h"
  #include "tensorflow/core/platform/cpu_info.h"
  +#include "tensorflow/core/platform/stringprintf.h"
  #include "tensorflow/core/util/ptr_util.h"
  namespace tensorflow {
  @@ -51,7 +52,15 @@ class ModelDatasetOp::Dataset : public DatasetBase {
  input_(input),
  algorithm_(algorithm),
  cpu_budget_(cpu_budget),
  - ram_budget_(ram_budget) {
  + ram_budget_(ram_budget),
  + traceme_metadata_(
  + {{"algorithm", algorithm == model::AutotuneAlgorithm::HILL_CLIMB
  + ? "hill climb"
  + : "gradient descent"},
  + {"cpu_budget",
  + strings::Printf("%lld", static_cast<long long>(cpu_budget))},
  + {"ram_budget",
  + strings::Printf("%lldB", static_cast<long long>(ram_budget))}}) {
  input_->Ref();
  }
  @@ -174,6 +183,10 @@ class ModelDatasetOp::Dataset : public DatasetBase {
  return Status::OK();
  }
  + TraceMeMetadata GetTraceMeMetadata() const override {
  + return dataset()->traceme_metadata_;
  + }
  +
  private:
  Status EnsureModelThreadStarted(IteratorContext* ctx)
  TF_EXCLUSIVE_LOCKS_REQUIRED(mu_) {
  @@ -257,6 +270,7 @@ class ModelDatasetOp::Dataset : public DatasetBase {
  const model::AutotuneAlgorithm algorithm_;
  const int64 cpu_budget_;
  const int64 ram_budget_;
  + const TraceMeMetadata traceme_metadata_;
  };
  ModelDatasetOp::ModelDatasetOp(OpKernelConstruction* ctx)
  