wip

src/ngraph/runtime/backend.cpp

@@ -91,8 +91,12 @@ std::shared_ptr<runtime::Executable> runtime::Backend::load(istream& input_strea
     throw runtime_error("load opertion unimplemented.");
 }
 
-runtime::Backend::AsyncEvent::AsyncEvent(Type type, void* p, size_t size_in_bytes)
+runtime::Backend::AsyncEvent::AsyncEvent(Type type,
+                                         size_t buffer_number,
+                                         void* p,
+                                         size_t size_in_bytes)
     : m_type{type}
+    , m_buffer_number{buffer_number}
     , m_data{p}
     , m_size_in_bytes{size_in_bytes}
     , m_executable{nullptr}
@@ -101,10 +105,12 @@ runtime::Backend::AsyncEvent::AsyncEvent(Type type, void* p, size_t size_in_byte
 {
 }
 
-runtime::Backend::AsyncEvent::AsyncEvent(const shared_ptr<Executable>& executable,
+runtime::Backend::AsyncEvent::AsyncEvent(size_t buffer_number,
+                                         const shared_ptr<Executable>& executable,
                                          const vector<shared_ptr<runtime::Tensor>>& outputs,
                                          const vector<shared_ptr<runtime::Tensor>>& inputs)
     : m_type{Type::EXECUTE}
+    , m_buffer_number{buffer_number}
     , m_data{nullptr}
     , m_size_in_bytes{0}
     , m_executable{executable}
@@ -115,12 +121,14 @@ runtime::Backend::AsyncEvent::AsyncEvent(const shared_ptr<Executable>& executabl
 
 void runtime::Backend::post_async_read_event(void* p,
                                              size_t size_in_bytes,
+                                             size_t buffer_number,
                                              std::promise<void>& promise)
 {
 }
 
 void runtime::Backend::post_async_write_event(const void* p,
                                               size_t size_in_bytes,
+                                              size_t buffer_number,
                                               std::promise<void>& promise)
 {
 }
@@ -129,6 +137,7 @@ void runtime::Backend::post_async_execute_event(
     const std::shared_ptr<Executable>& executable,
     const std::vector<std::shared_ptr<runtime::Tensor>>& outputs,
     const std::vector<std::shared_ptr<runtime::Tensor>>& inputs,
+    size_t buffer_number,
     std::promise<void>& promise)
 {
 }

src/ngraph/runtime/backend.hpp

@@ -163,11 +163,13 @@ protected:
         }
         const std::vector<std::shared_ptr<runtime::Tensor>>* get_inputs() const { return m_inputs; }
     private:
-        AsyncEvent(Type, void* p, size_t size_in_bytes);
-        AsyncEvent(const std::shared_ptr<Executable>& m_executable,
+        AsyncEvent(Type type, size_t buffer_number, void* p, size_t size_in_bytes);
+        AsyncEvent(size_t buffer_number,
+                   const std::shared_ptr<Executable>& m_executable,
                    const std::vector<std::shared_ptr<runtime::Tensor>>& m_outputs,
                    const std::vector<std::shared_ptr<runtime::Tensor>>& m_inputs);
         const Type m_type;
+        size_t m_buffer_number;
         void* m_data;
         const size_t m_size_in_bytes;
         std::shared_ptr<Executable> m_executable;
@@ -175,10 +177,17 @@ protected:
         const std::vector<std::shared_ptr<runtime::Tensor>>* m_inputs;
     };
 
-    void post_async_read_event(void* p, size_t size_in_bytes, std::promise<void>& promise);
-    void post_async_write_event(const void* p, size_t size_in_bytes, std::promise<void>& promise);
+    void post_async_read_event(void* p,
+                               size_t size_in_bytes,
+                               size_t buffer_number,
+                               std::promise<void>& promise);
+    void post_async_write_event(const void* p,
+                                size_t size_in_bytes,
+                                size_t buffer_number,
+                                std::promise<void>& promise);
     void post_async_execute_event(const std::shared_ptr<Executable>& executable,
                                   const std::vector<std::shared_ptr<runtime::Tensor>>& outputs,
                                   const std::vector<std::shared_ptr<runtime::Tensor>>& inputs,
+                                  size_t buffer_number,
                                   std::promise<void>& promise);
 };

src/ngraph/runtime/tensor.cpp

@@ -98,12 +98,12 @@ void runtime::Tensor::copy_from(const ngraph::runtime::Tensor& source)
     write(buffer.get_ptr(), 0, size);
 }
 
-future<void> runtime::Tensor::begin_write(const void* p, size_t n)
+future<void> runtime::Tensor::begin_write(const void* p, size_t size_in_bytes, size_t buffer_number)
 {
     if (m_backend)
     {
         auto f = m_promise.get_future();
-        m_backend->post_async_write_event(p, n, m_promise);
+        m_backend->post_async_write_event(p, size_in_bytes, buffer_number, m_promise);
         return f;
     }
     else
@@ -117,11 +117,21 @@ future<void> runtime::Tensor::begin_write(const void* p, size_t n)
     // return f;
 }
 
-future<void> runtime::Tensor::begin_read(void* p, size_t n)
+future<void> runtime::Tensor::begin_read(void* p, size_t size_in_bytes, size_t buffer_number)
 {
-    using namespace std::placeholders;
-    auto f = m_promise.get_future();
-    auto bound_f = bind(&Tensor::read, this, _1, _2, _3);
-    async(bound_f, p, 0, n);
-    return f;
+    if (m_backend)
+    {
+        auto f = m_promise.get_future();
+        m_backend->post_async_read_event(p, size_in_bytes, buffer_number, m_promise);
+        return f;
+    }
+    else
+    {
+        throw runtime_error("Async operations not supported for this backend");
+    }
+    // using namespace std::placeholders;
+    // auto f = m_promise.get_future();
+    // auto bound_f = bind(&Tensor::read, this, _1, _2, _3);
+    // async(bound_f, p, 0, n);
+    // return f;
 }

src/ngraph/runtime/tensor.hpp

@@ -119,16 +119,20 @@ namespace ngraph
             /// \brief Write bytes into the tensor. The data buffer pointed to by `p` must
             ///     be kept live until after the future is signaled complete
             /// \param p Pointer to source of data
-            /// \param n Number of bytes to write, must be integral number of elements.
+            /// \param size_in_bytes Number of bytes to write, must be integral number of elements.
+            /// \param buffer_number For double-buffering, which buffer to write.
             /// \return std::future to track the operation
-            virtual std::future<void> begin_write(const void* p, size_t n);
+            virtual std::future<void>
+                begin_write(const void* p, size_t size_in_bytes, size_t buffer_number);
 
             /// \brief Read bytes from the tensor. The data buffer pointed to by `p` must
             ///     be kept live until after the future is signaled complete
             /// \param p Pointer to destination for data
-            /// \param n Number of bytes to read, must be integral number of elements.
+            /// \param size_in_bytes Number of bytes to read, must be integral number of elements.
+            /// \param buffer_number For double-buffering, which buffer to read.
             /// \return std::future to track the operation
-            virtual std::future<void> begin_read(void* p, size_t n);
+            virtual std::future<void>
+                begin_read(void* p, size_t size_in_bytes, size_t buffer_number);
 
             /// \brief copy bytes directly from source to this tensor
             /// \param source The source tensor

test/async.cpp

@@ -70,9 +70,9 @@ TEST(async, tensor_read_write)
     shared_ptr<runtime::Tensor> b = backend->create_tensor(element::f32, shape);
     shared_ptr<runtime::Tensor> r = backend->create_tensor(element::f32, shape);
 
-    auto future_a = a->begin_write(data.data(), data.size() * sizeof(float));
-    auto future_b = b->begin_write(data.data(), data.size() * sizeof(float));
-    auto future_r = r->begin_read(data_r.data(), data_r.size() * sizeof(float));
+    auto future_a = a->begin_write(data.data(), data.size() * sizeof(float), 0);
+    auto future_b = b->begin_write(data.data(), data.size() * sizeof(float), 0);
+    auto future_r = r->begin_read(data_r.data(), data_r.size() * sizeof(float), 0);
     ASSERT_TRUE(future_a.valid());
     ASSERT_TRUE(future_b.valid());
     ASSERT_TRUE(future_r.valid());