inference/unify output buffer management (#11569)

Superjomn · web-flow · commit a009272ec7b5 · 2018-06-20T15:25:17.000+08:00
diff --git a/paddle/contrib/inference/demo/simple_on_word2vec.cc b/paddle/contrib/inference/demo/simple_on_word2vec.cc
@@ -40,10 +40,9 @@ void Main(bool use_gpu) {
     //# 2. Prepare input.
     int64_t data[4] = {1, 2, 3, 4};
 
-    PaddleBuf buf{.data = data, .length = sizeof(data)};
     PaddleTensor tensor{.name = "",
                         .shape = std::vector<int>({4, 1}),
-                        .data = buf,
+                        .data = PaddleBuf(data, sizeof(data)),
                         .dtype = PaddleDType::INT64};
 
     // For simplicity, we set all the slots with the same data.
@@ -55,14 +54,12 @@ void Main(bool use_gpu) {
 
     //# 4. Get output.
     ASSERT_EQ(outputs.size(), 1UL);
-    LOG(INFO) << "output buffer size: " << outputs.front().data.length;
-    const size_t num_elements = outputs.front().data.length / sizeof(float);
+    LOG(INFO) << "output buffer size: " << outputs.front().data.length();
+    const size_t num_elements = outputs.front().data.length() / sizeof(float);
     // The outputs' buffers are in CPU memory.
     for (size_t i = 0; i < std::min(5UL, num_elements); i++) {
-      LOG(INFO) << static_cast<float*>(outputs.front().data.data)[i];
+      LOG(INFO) << static_cast<float*>(outputs.front().data.data())[i];
     }
-    // TODO(Superjomn): this is should be free automatically
-    free(outputs[0].data.data);
   }
 }
 
@@ -86,10 +83,9 @@ void MainThreads(int num_threads, bool use_gpu) {
       for (int batch_id = 0; batch_id < num_batches; ++batch_id) {
         // 2. Dummy Input Data
         int64_t data[4] = {1, 2, 3, 4};
-        PaddleBuf buf{.data = data, .length = sizeof(data)};
         PaddleTensor tensor{.name = "",
                             .shape = std::vector<int>({4, 1}),
-                            .data = buf,
+                            .data = PaddleBuf(data, sizeof(data)),
                             .dtype = PaddleDType::INT64};
         std::vector<PaddleTensor> inputs(4, tensor);
         std::vector<PaddleTensor> outputs;
@@ -99,13 +95,13 @@ void MainThreads(int num_threads, bool use_gpu) {
         // 4. Get output.
         ASSERT_EQ(outputs.size(), 1UL);
         LOG(INFO) << "TID: " << tid << ", "
-                  << "output buffer size: " << outputs.front().data.length;
-        const size_t num_elements = outputs.front().data.length / sizeof(float);
+                  << "output buffer size: " << outputs.front().data.length();
+        const size_t num_elements =
+            outputs.front().data.length() / sizeof(float);
         // The outputs' buffers are in CPU memory.
         for (size_t i = 0; i < std::min(5UL, num_elements); i++) {
-          LOG(INFO) << static_cast<float*>(outputs.front().data.data)[i];
+          LOG(INFO) << static_cast<float*>(outputs.front().data.data())[i];
         }
-        free(outputs[0].data.data);
       }
     });
   }
diff --git a/paddle/contrib/inference/paddle_inference_api.cc b/paddle/contrib/inference/paddle_inference_api.cc
@@ -13,3 +13,53 @@ See the License for the specific language governing permissions and
 limitations under the License. */
 
 #include "paddle/contrib/inference/paddle_inference_api.h"
+
+namespace paddle {
+
+PaddleBuf::PaddleBuf(PaddleBuf&& other)
+    : data_(other.data_),
+      length_(other.length_),
+      memory_owned_(other.memory_owned_) {
+  other.memory_owned_ = false;
+  other.data_ = nullptr;
+  other.length_ = 0;
+}
+
+PaddleBuf::PaddleBuf(const PaddleBuf& other) { *this = other; }
+
+PaddleBuf& PaddleBuf::operator=(const PaddleBuf& other) {
+  // only the buffer with external memory can be copied
+  assert(!other.memory_owned_);
+  data_ = other.data_;
+  length_ = other.length_;
+  memory_owned_ = other.memory_owned_;
+  return *this;
+}
+
+void PaddleBuf::Resize(size_t length) {
+  // Only the owned memory can be reset, the external memory can't be changed.
+  if (length_ == length) return;
+  assert(memory_owned_);
+  Free();
+  data_ = new char[length];
+  length_ = length;
+  memory_owned_ = true;
+}
+
+void PaddleBuf::Reset(void* data, size_t length) {
+  Free();
+  memory_owned_ = false;
+  data_ = data;
+  length_ = length;
+}
+
+void PaddleBuf::Free() {
+  if (memory_owned_ && data_) {
+    assert(length_ > 0);
+    delete static_cast<char*>(data_);
+    data_ = nullptr;
+    length_ = 0;
+  }
+}
+
+}  // namespace paddle
diff --git a/paddle/contrib/inference/paddle_inference_api.h b/paddle/contrib/inference/paddle_inference_api.h
@@ -21,6 +21,7 @@ limitations under the License. */
 
 #pragma once
 
+#include <cassert>
 #include <memory>
 #include <string>
 #include <vector>
@@ -32,12 +33,38 @@ enum PaddleDType {
   INT64,
 };
 
-struct PaddleBuf {
-  void* data;     // pointer to the data memory.
-  size_t length;  // number of memory bytes.
+class PaddleBuf {
+ public:
+  PaddleBuf() = default;
+  PaddleBuf(PaddleBuf&& other);
+  // Copy only available when memory is managed externally.
+  explicit PaddleBuf(const PaddleBuf&);
+  PaddleBuf& operator=(const PaddleBuf&);
+  // Do not own the memory.
+  PaddleBuf(void* data, size_t length)
+      : data_(data), length_(length), memory_owned_{false} {}
+  // Own memory.
+  PaddleBuf(size_t length)
+      : data_(new char[length]), length_(length), memory_owned_(true) {}
+  // Resize to `length` bytes.
+  void Resize(size_t length);
+  // Reset to external memory.
+  void Reset(void* data, size_t length);
+  bool empty() const { return length_ == 0; }
+  void* data() const { return data_; }
+  size_t length() const { return length_; }
+
+  ~PaddleBuf() { Free(); }
+
+ private:
+  void Free();
+  void* data_{nullptr};  // pointer to the data memory.
+  size_t length_{0};     // number of memory bytes.
+  bool memory_owned_{true};
 };
 
 struct PaddleTensor {
+  PaddleTensor() = default;
   std::string name;  // variable name.
   std::vector<int> shape;
   // TODO(Superjomn) for LoD support, add a vector<vector<int>> field if needed.
@@ -67,8 +94,9 @@ class PaddlePredictor {
 
   // Predict an record.
   // The caller should be responsible for allocating and releasing the memory of
-  // `inputs`. `inputs` should be alive until Run returns. caller should be
-  // responsible for releasing the memory of `output_data`.
+  // `inputs`. `inputs` should be available until Run returns. Caller should be
+  // responsible for the output tensor's buffer, either allocated or passed from
+  // outside.
   virtual bool Run(const std::vector<PaddleTensor>& inputs,
                    std::vector<PaddleTensor>* output_data) = 0;
 
diff --git a/paddle/contrib/inference/paddle_inference_api_anakin_engine.cc b/paddle/contrib/inference/paddle_inference_api_anakin_engine.cc
@@ -48,7 +48,7 @@ bool PaddleInferenceAnakinPredictor::Run(
     auto d_tensor_in_p = executor_.get_in(input.name);
     float *d_data_p = d_tensor_in_p->mutable_data();
     if (cudaMemcpy(d_data_p,
-                   static_cast<float *>(input.data.data),
+                   static_cast<float *>(input.data.data()),
                    d_tensor_in_p->valid_size() * sizeof(float),
                    cudaMemcpyHostToDevice) != 0) {
       LOG(ERROR) << "copy data from CPU to GPU error";
@@ -65,8 +65,11 @@ bool PaddleInferenceAnakinPredictor::Run(
   for (auto &output : *output_data) {
     auto *tensor = executor_.get_out(output.name);
     output.shape = tensor->shape();
+    if (output.data.length() < tensor->valid_size() * sizeof(float)) {
+      output.data.Resize(tensor->valid_size() * sizeof(float));
+    }
     // Copy data from GPU -> CPU
-    if (cudaMemcpy(output.data.data,
+    if (cudaMemcpy(output.data.data(),
                    tensor->mutable_data(),
                    tensor->valid_size() * sizeof(float),
                    cudaMemcpyDeviceToHost) != 0) {
diff --git a/paddle/contrib/inference/paddle_inference_api_anakin_engine_tester.cc b/paddle/contrib/inference/paddle_inference_api_anakin_engine_tester.cc
@@ -37,28 +37,26 @@ TEST(inference, anakin) {
 
   float data[1 * 3 * 224 * 224] = {1.0f};
 
-  PaddleBuf buf{.data = data, .length = sizeof(data)};
   PaddleTensor tensor{.name = "input_0",
                       .shape = std::vector<int>({1, 3, 224, 224}),
-                      .data = buf,
+                      .data = PaddleBuf(data, sizeof(data)),
                       .dtype = PaddleDType::FLOAT32};
 
   // For simplicity, we set all the slots with the same data.
-  std::vector<PaddleTensor> paddle_tensor_feeds(1, tensor);
+  std::vector<PaddleTensor> paddle_tensor_feeds;
+  paddle_tensor_feeds.emplace_back(std::move(tensor));
 
-  float data_out[1000];
-
-  PaddleBuf buf_out{.data = data_out, .length = sizeof(data)};
   PaddleTensor tensor_out{.name = "prob_out",
                           .shape = std::vector<int>({1000, 1}),
-                          .data = buf_out,
+                          .data = PaddleBuf(),
                           .dtype = PaddleDType::FLOAT32};
 
-  std::vector<PaddleTensor> outputs(1, tensor_out);
+  std::vector<PaddleTensor> outputs;
+  outputs.emplace_back(std::move(tensor_out));
 
   ASSERT_TRUE(predictor->Run(paddle_tensor_feeds, &outputs));
 
-  float* data_o = static_cast<float*>(outputs[0].data.data);
+  float* data_o = static_cast<float*>(outputs[0].data.data());
   for (size_t j = 0; j < 1000; ++j) {
     LOG(INFO) << "output[" << j << "]: " << data_o[j];
   }
diff --git a/paddle/contrib/inference/paddle_inference_api_impl.cc b/paddle/contrib/inference/paddle_inference_api_impl.cc
@@ -178,8 +178,8 @@ bool NativePaddlePredictor::SetFeed(const std::vector<PaddleTensor> &inputs,
 
     // TODO(panyx0718): Init LoDTensor from existing memcpy to save a copy.
     std::memcpy(static_cast<void *>(input_ptr),
-                inputs[i].data.data,
-                inputs[i].data.length);
+                inputs[i].data.data(),
+                inputs[i].data.length());
     feeds->push_back(input);
   }
   return true;
@@ -241,10 +241,11 @@ bool NativePaddlePredictor::GetFetch(
     }
 
     outputs->at(i).shape = shape;
-    outputs->at(i).data.length = sizeof(float) * data.size();
-    outputs->at(i).data.data = malloc(outputs->at(i).data.length);
-    std::memcpy(
-        outputs->at(i).data.data, data.data(), outputs->at(i).data.length);
+    auto &buffer = outputs->at(i).data;
+    if (buffer.empty() || buffer.length() < sizeof(float) * data.size()) {
+      buffer.Resize(sizeof(float) * data.size());
+    }
+    std::memcpy(buffer.data(), data.data(), buffer.length());
     outputs->at(i).dtype = PaddleDType::FLOAT32;
     // TODO(panyx0718): support other types? fill tensor name? avoid a copy.
   }
diff --git a/paddle/contrib/inference/test_paddle_inference_api_impl.cc b/paddle/contrib/inference/test_paddle_inference_api_impl.cc
@@ -27,13 +27,12 @@ namespace paddle {
 
 PaddleTensor LodTensorToPaddleTensor(framework::LoDTensor* t) {
   PaddleTensor pt;
-  pt.data.data = t->data<void>();
 
   if (t->type() == typeid(int64_t)) {
-    pt.data.length = t->numel() * sizeof(int64_t);
+    pt.data.Reset(t->data<void>(), t->numel() * sizeof(int64_t));
     pt.dtype = PaddleDType::INT64;
   } else if (t->type() == typeid(float)) {
-    pt.data.length = t->numel() * sizeof(float);
+    pt.data.Reset(t->data<void>(), t->numel() * sizeof(float));
     pt.dtype = PaddleDType::FLOAT32;
   } else {
     LOG(FATAL) << "unsupported type.";
@@ -79,8 +78,8 @@ void MainWord2Vec(bool use_gpu) {
   std::vector<PaddleTensor> outputs;
   ASSERT_TRUE(predictor->Run(paddle_tensor_feeds, &outputs));
   ASSERT_EQ(outputs.size(), 1UL);
-  size_t len = outputs[0].data.length;
-  float* data = static_cast<float*>(outputs[0].data.data);
+  size_t len = outputs[0].data.length();
+  float* data = static_cast<float*>(outputs[0].data.data());
   for (size_t j = 0; j < len / sizeof(float); ++j) {
     ASSERT_LT(data[j], 1.0);
     ASSERT_GT(data[j], -1.0);
@@ -103,8 +102,6 @@ void MainWord2Vec(bool use_gpu) {
     EXPECT_LT(lod_data[i] - data[i], 1e-3);
     EXPECT_GT(lod_data[i] - data[i], -1e-3);
   }
-
-  free(outputs[0].data.data);
 }
 
 void MainImageClassification(bool use_gpu) {
@@ -143,13 +140,12 @@ void MainImageClassification(bool use_gpu) {
   std::vector<PaddleTensor> outputs;
   ASSERT_TRUE(predictor->Run(paddle_tensor_feeds, &outputs));
   ASSERT_EQ(outputs.size(), 1UL);
-  size_t len = outputs[0].data.length;
-  float* data = static_cast<float*>(outputs[0].data.data);
+  size_t len = outputs[0].data.length();
+  float* data = static_cast<float*>(outputs[0].data.data());
   float* lod_data = output1.data<float>();
   for (size_t j = 0; j < len / sizeof(float); ++j) {
     EXPECT_NEAR(lod_data[j], data[j], 1e-3);
   }
-  free(data);
 }
 
 void MainThreadsWord2Vec(bool use_gpu) {
@@ -192,8 +188,8 @@ void MainThreadsWord2Vec(bool use_gpu) {
 
       // check outputs range
       ASSERT_EQ(local_outputs.size(), 1UL);
-      const size_t len = local_outputs[0].data.length;
-      float* data = static_cast<float*>(local_outputs[0].data.data);
+      const size_t len = local_outputs[0].data.length();
+      float* data = static_cast<float*>(local_outputs[0].data.data());
       for (size_t j = 0; j < len / sizeof(float); ++j) {
         ASSERT_LT(data[j], 1.0);
         ASSERT_GT(data[j], -1.0);
@@ -205,7 +201,6 @@ void MainThreadsWord2Vec(bool use_gpu) {
       for (int i = 0; i < refs[tid].numel(); ++i) {
         EXPECT_NEAR(ref_data[i], data[i], 1e-3);
       }
-      free(data);
     });
   }
   for (int i = 0; i < num_jobs; ++i) {
@@ -251,14 +246,13 @@ void MainThreadsImageClassification(bool use_gpu) {
 
       // check outputs correctness
       ASSERT_EQ(local_outputs.size(), 1UL);
-      const size_t len = local_outputs[0].data.length;
-      float* data = static_cast<float*>(local_outputs[0].data.data);
+      const size_t len = local_outputs[0].data.length();
+      float* data = static_cast<float*>(local_outputs[0].data.data());
       float* ref_data = refs[tid].data<float>();
       EXPECT_EQ(refs[tid].numel(), len / sizeof(float));
       for (int i = 0; i < refs[tid].numel(); ++i) {
         EXPECT_NEAR(ref_data[i], data[i], 1e-3);
       }
-      free(data);
     });
   }
   for (int i = 0; i < num_jobs; ++i) {
