Merge pull request #8991 from reyoung/feature/shuffle_reader

Feature/shuffle reader

Author: reyoung

paddle/fluid/framework/operator.cc

@@ -445,15 +445,7 @@ class RuntimeInferShapeContext : public InferShapeContext {
   }
 
   std::vector<DDim> GetRepeatedDims(const std::string& name) const override {
-    Variable* var = scope_.FindVar(name);
-    if (var->IsType<ReaderHolder>()) {
-      return var->Get<ReaderHolder>().shapes();
-    } else {
-      PADDLE_THROW(
-          "Only ReaderHolder support 'GetRepeatedDims', but Variable %s's "
-          "type_id is %s.",
-          name, var->Type().name());
-    }
+    PADDLE_THROW("Only compile time support this method");
   }
 
   void SetDim(const std::string& name, const DDim& dim) override {
@@ -470,15 +462,7 @@ class RuntimeInferShapeContext : public InferShapeContext {
 
   void SetRepeatedDims(const std::string& name,
                        const std::vector<DDim>& dims) override {
-    Variable* var = scope_.FindVar(name);
-    if (var->IsType<ReaderHolder>()) {
-      var->GetMutable<ReaderHolder>()->set_shapes(dims);
-    } else {
-      PADDLE_THROW(
-          "Only ReaderHolder support 'SetRepeatedDims', but Variable %s's "
-          "type_id is %s.",
-          name, var->Type().name());
-    }
+    PADDLE_THROW("Only compile time support this method");
   }
 
   proto::VarType::Type GetVarType(const std::string& name) const override {

paddle/fluid/framework/reader.cc

@@ -16,14 +16,22 @@
 
 namespace paddle {
 namespace framework {
+ReaderBase::~ReaderBase() {}
 
-DDim ReaderBase::shape(size_t idx) const {
-  PADDLE_ENFORCE_LT(
-      idx, shapes_.size(),
-      "Cannot get the %d'th shape, 'shapes_' only has %d elements.", idx,
-      shapes_.size());
-  return shapes_[idx];
-}
+FileReader::FileReader(const std::vector<DDim> &dims) : dims_(dims) {}
+
+void FileReader::ReadNext(std::vector<LoDTensor> *out) {
+  ReadNextImpl(out);
+  PADDLE_ENFORCE_EQ(out->size(), dims_.size());
+  for (size_t i = 0; i < dims_.size(); ++i) {
+    auto &actual = out->at(i).dims();
+    auto &expect = dims_[i];
 
+    PADDLE_ENFORCE_EQ(actual.size(), expect.size());
+    for (int j = 0; j < actual.size(); ++j) {
+      PADDLE_ENFORCE(actual[i] == expect[i] || expect[i] == -1);
+    }
+  }
+}
 }  // namespace framework
 }  // namespace paddle

paddle/fluid/framework/reader.h

@@ -16,40 +16,29 @@
 
 #include "paddle/fluid/framework/ddim.h"
 #include "paddle/fluid/framework/lod_tensor_array.h"
+#include "paddle/fluid/platform/place.h"
+
+#include <memory>
+#include <thread>
+#include <vector>
 
 namespace paddle {
 namespace framework {
 
 class ReaderBase {
  public:
-  explicit ReaderBase(const std::vector<DDim>& shapes) : shapes_(shapes) {
-    PADDLE_ENFORCE(!shapes_.empty());
-  }
   virtual void ReadNext(std::vector<LoDTensor>* out) = 0;
 
   virtual void ReInit() = 0;
 
-  DDim shape(size_t idx) const;
-  std::vector<DDim> shapes() const { return shapes_; }
-  void set_shapes(const std::vector<DDim>& shapes) { shapes_ = shapes; }
-
   virtual bool HasNext() const = 0;
 
-  virtual ~ReaderBase() {}
-
- protected:
-  std::vector<DDim> shapes_;
-};
-
-class FileReader : public ReaderBase {
- public:
-  explicit FileReader(const std::vector<DDim>& shapes) : ReaderBase(shapes) {}
+  virtual ~ReaderBase();
 };
 
 class DecoratedReader : public ReaderBase {
  public:
-  explicit DecoratedReader(ReaderBase* reader)
-      : ReaderBase(reader->shapes()), reader_(reader) {
+  explicit DecoratedReader(ReaderBase* reader) : ReaderBase(), reader_(reader) {
     PADDLE_ENFORCE_NOT_NULL(reader_);
   }
 
@@ -61,6 +50,19 @@ class DecoratedReader : public ReaderBase {
   ReaderBase* reader_;
 };
 
+class FileReader : public ReaderBase {
+ public:
+  explicit FileReader(const std::vector<DDim>& dims);
+
+  void ReadNext(std::vector<LoDTensor>* out) override;
+
+ protected:
+  virtual void ReadNextImpl(std::vector<LoDTensor>* out) = 0;
+
+ private:
+  std::vector<DDim> dims_;
+};
+
 // The ReaderHolder is used as reader' unified wrapper,
 // making it easier to access different type reader in Variables.
 class ReaderHolder {
@@ -78,19 +80,6 @@ class ReaderHolder {
     reader_->ReInit();
   }
 
-  DDim shape(size_t idx) const {
-    PADDLE_ENFORCE_NOT_NULL(reader_);
-    return reader_->shape(idx);
-  }
-  std::vector<DDim> shapes() const {
-    PADDLE_ENFORCE_NOT_NULL(reader_);
-    return reader_->shapes();
-  }
-  void set_shapes(const std::vector<DDim>& shapes) {
-    PADDLE_ENFORCE_NOT_NULL(reader_);
-    reader_->set_shapes(shapes);
-  }
-
   bool HasNext() const { return reader_->HasNext(); }
 
  private:

paddle/fluid/operators/reader/create_double_buffer_reader_op.cc

@@ -24,11 +24,31 @@ static constexpr size_t kDoubleBufferSize = 2;
 
 class DoubleBufferReader : public framework::DecoratedReader {
  public:
-  explicit DoubleBufferReader(ReaderBase* reader)
-      : DecoratedReader(reader),
-        buffer_(framework::MakeChannel<std::vector<framework::LoDTensor>>(
-            kDoubleBufferSize)) {
-    std::thread prefetch(&DoubleBufferReader::PrefetchThreadFunc, this);
+  struct Item {
+    Item() : ctx_(nullptr) {}
+
+    std::vector<framework::LoDTensor> payloads_;
+    platform::DeviceContext* ctx_;
+  };
+
+  explicit DoubleBufferReader(
+      ReaderBase* reader, platform::Place target_place = platform::CPUPlace())
+      : DecoratedReader(reader), place_(target_place) {
+    for (size_t i = 0; i < kDoubleBufferSize; ++i) {
+      if (platform::is_gpu_place(place_)) {
+#ifdef PADDLE_WITH_CUDA
+        ctxs_.emplace_back(new platform::CUDADeviceContext(
+            boost::get<platform::CUDAPlace>(place_)));
+#endif
+      }
+    }
+
+    start_thread();
+  }
+
+  void start_thread() {
+    buffer_ = framework::MakeChannel<Item>(kDoubleBufferSize);
+    std::thread prefetch([this] { PrefetchThreadFunc(); });
     prefetch.detach();
   }
 
@@ -42,7 +62,10 @@ class DoubleBufferReader : public framework::DecoratedReader {
  private:
   void PrefetchThreadFunc();
 
-  framework::Channel<std::vector<framework::LoDTensor>>* buffer_;
+  framework::Channel<Item>* buffer_;
+  platform::Place place_;
+  std::vector<std::unique_ptr<platform::DeviceContext>> ctxs_;
+  mutable Item local_buffer_;
 };
 
 class CreateDoubleBufferReaderOp : public framework::OperatorBase {
@@ -56,7 +79,20 @@ class CreateDoubleBufferReaderOp : public framework::OperatorBase {
                                         ->Get<framework::ReaderHolder>();
     auto* out = scope.FindVar(Output("Out"))
                     ->template GetMutable<framework::ReaderHolder>();
-    out->Reset(new DoubleBufferReader(underlying_reader.Get()));
+
+    auto place_str = Attr<std::string>("place");
+    platform::Place place;
+    if (place_str == "CPU") {
+      place = platform::CPUPlace();
+    } else {
+      std::istringstream sin(place_str);
+      sin.seekg(std::string("CUDA:").size(), std::ios::beg);
+      size_t num;
+      sin >> num;
+      place = platform::CUDAPlace(static_cast<int>(num));
+    }
+
+    out->Reset(new DoubleBufferReader(underlying_reader.Get(), place));
   }
 };
 
@@ -71,44 +107,73 @@ class CreateDoubleBufferReaderOpMaker : public DecoratedReaderMakerBase {
       It launches another thread to execute the 'underlying reader' asynchronously, 
       which prevents reading process from blocking subsequent training.
     )DOC");
+    std::unordered_set<std::string> enum_range;
+    constexpr size_t kMaxCUDADevs = 128;
+    for (size_t i = 0; i < kMaxCUDADevs; ++i) {
+      enum_range.insert(string::Sprintf("CUDA:%d", i));
+    }
+    enum_range.insert("CPU");
+    AddAttr<std::string>("place", "The double buffer place, default is CPU")
+        .SetDefault("CPU")
+        .InEnum({enum_range});
   }
 };
 
 void DoubleBufferReader::ReadNext(std::vector<framework::LoDTensor>* out) {
-  out->clear();
-  buffer_->Receive(out);
+  if (local_buffer_.payloads_.empty()) {
+    buffer_->Receive(&local_buffer_);
+  }
+
+  *out = local_buffer_.payloads_;
+  local_buffer_.payloads_.clear();
+  if (local_buffer_.ctx_) {
+    local_buffer_.ctx_->Wait();
+  }
 }
 
 void DoubleBufferReader::ReInit() {
   reader_->ReInit();
   buffer_->Close();
-  // The existing prefetch thread will terminate for the buffer_ is closed.
-  buffer_ = framework::MakeChannel<std::vector<framework::LoDTensor>>(
-      kDoubleBufferSize);
-  std::thread prefetch(&DoubleBufferReader::PrefetchThreadFunc, this);
-  prefetch.detach();
+  start_thread();
 }
 
 void DoubleBufferReader::PrefetchThreadFunc() {
   VLOG(5) << "A new prefetch thread starts.";
-  while (true) {
-    std::vector<framework::LoDTensor> batch;
-    reader_->ReadNext(&batch);
-    if (batch.empty()) {
-      // EOF
-      buffer_->Close();
-      VLOG(5) << "Reached the end of the file. The prefetch thread terminates.";
-      break;
+  size_t gpu_ctx_offset = 0;
+  while (reader_->HasNext()) {
+    Item batch;
+    reader_->ReadNext(&batch.payloads_);
+    if (platform::is_gpu_place(place_)) {
+      std::vector<framework::LoDTensor> gpu_batch;
+      auto& gpu_ctx = this->ctxs_[gpu_ctx_offset++];
+      gpu_ctx_offset %= this->ctxs_.size();
+      gpu_batch.resize(batch.payloads_.size());
+      for (size_t i = 0; i < batch.payloads_.size(); ++i) {
+        framework::TensorCopy(batch.payloads_[i], place_, *gpu_ctx,
+                              &gpu_batch[i]);
+        gpu_batch[i].set_lod(batch.payloads_[i].lod());
+      }
+      batch.ctx_ = gpu_ctx.get();
+      std::swap(gpu_batch, batch.payloads_);
     }
+
     if (!buffer_->Send(&batch)) {
       VLOG(5) << "WARNING: The double buffer channel has been closed. The "
                  "prefetch thread terminates.";
       break;
     }
   }
+  buffer_->Close();
 }
 
-bool DoubleBufferReader::HasNext() const { PADDLE_THROW("Not Implemented"); }
+bool DoubleBufferReader::HasNext() const {
+  if (local_buffer_.payloads_.empty()) {
+    bool ok = buffer_->Receive(&local_buffer_);
+    return ok;
+  } else {
+    return true;
+  }
+}
 
 }  // namespace reader
 }  // namespace operators

paddle/fluid/operators/reader/create_random_data_generator_op.cc

@@ -19,11 +19,11 @@ namespace operators {
 namespace reader {
 
 template <typename T>
-class RandomDataGenerator : public framework::FileReader {
+class RandomDataGenerator : public framework::ReaderBase {
  public:
   RandomDataGenerator(const std::vector<framework::DDim>& shapes, float min,
                       float max)
-      : FileReader(shapes), min_(min), max_(max) {
+      : framework::ReaderBase(), min_(min), max_(max), shapes_(shapes) {
     PADDLE_ENFORCE_LE(
         min, max, "'min' shouldn't be greater than 'max'.(%f vs %f)", min, max);
     unsigned int seed = std::random_device()();
@@ -59,6 +59,7 @@ class RandomDataGenerator : public framework::FileReader {
   float max_;
   std::minstd_rand engine_;
   std::uniform_real_distribution<float> dist_;
+  std::vector<framework::DDim> shapes_;
 };
 
 template <typename T>

paddle/fluid/operators/reader/create_recordio_file_reader_op.cc

@@ -20,21 +20,22 @@ namespace operators {
 namespace reader {
 class RecordIOFileReader : public framework::FileReader {
  public:
-  RecordIOFileReader(const std::string& filename,
-                     const std::vector<framework::DDim>& shapes)
-      : FileReader(shapes),
+  explicit RecordIOFileReader(const std::string& filename,
+                              const std::vector<framework::DDim>& dims)
+      : FileReader(dims),
         scanner_(filename),
         dev_ctx_(*platform::DeviceContextPool::Instance().Get(
             platform::CPUPlace())) {}
 
-  void ReadNext(std::vector<framework::LoDTensor>* out) override {
-    *out = framework::ReadFromRecordIO(scanner_, dev_ctx_);
-  }
-
   bool HasNext() const override { return scanner_.HasNext(); }
 
   void ReInit() override { scanner_.Reset(); }
 
+ protected:
+  void ReadNextImpl(std::vector<framework::LoDTensor>* out) override {
+    *out = framework::ReadFromRecordIO(scanner_, dev_ctx_);
+  }
+
  private:
   recordio::Scanner scanner_;
   const platform::DeviceContext& dev_ctx_;
@@ -54,12 +55,12 @@ class CreateRecordIOReaderOp : public framework::OperatorBase {
                       int(shape_concat.size()),
                       "The accumulate of all ranks should be equal to the "
                       "shape concat's length.");
-    std::vector<framework::DDim> shapes = RestoreShapes(shape_concat, ranks);
     std::string filename = Attr<std::string>("filename");
 
     auto* out = scope.FindVar(Output("Out"))
                     ->template GetMutable<framework::ReaderHolder>();
-    out->Reset(new RecordIOFileReader(filename, shapes));
+    out->Reset(
+        new RecordIOFileReader(filename, RestoreShapes(shape_concat, ranks)));
   }
 };
 
@@ -85,3 +86,5 @@ namespace reader = paddle::operators::reader;
 REGISTER_FILE_READER_OPERATOR(create_recordio_file_reader,
                               reader::CreateRecordIOReaderOp,
                               reader::CreateRecordIOReaderOpMaker);
+
+REGISTER_FILE_READER(recordio, reader::RecordIOFileReader);