[Phi] Add phi device context pool (#40635)

* add phi device context pool

* change year

* fix compile error

* fix operator = error

* refine init impl

* polish details

* refine init impl

Author: chenwhql

paddle/fluid/platform/CMakeLists.txt

@@ -117,7 +117,7 @@ endif()
 cc_library(cudnn_workspace_helper SRCS cudnn_workspace_helper.cc DEPS boost)
 
 # seperate init from device_context to avoid cycle dependencies
-cc_library(init SRCS init.cc DEPS device_context custom_kernel)
+cc_library(init SRCS init.cc DEPS device_context custom_kernel context_pool)
 
 # memcpy depends on device_context, here add deps individually for
 # avoiding cycle dependencies

paddle/fluid/platform/device_context.h

@@ -916,6 +916,11 @@ class DeviceContextPool {
 
   size_t size() const { return device_contexts_.size(); }
 
+  const std::map<Place, std::shared_future<std::unique_ptr<DeviceContext>>>&
+  device_contexts() const {
+    return device_contexts_;
+  }
+
  private:
   static DeviceContextPool* pool;
   std::map<Place, std::shared_future<std::unique_ptr<DeviceContext>>>

paddle/phi/api/include/context_pool.h

@@ -0,0 +1,81 @@
+/* Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#pragma once
+
+#include "paddle/phi/common/place.h"
+#include "paddle/phi/core/macros.h"
+#include "paddle/utils/flat_hash_map.h"
+
+namespace phi {
+class DeviceContext;
+class CPUContext;
+class GPUContext;
+}  // namespace phi
+
+namespace paddle {
+namespace experimental {
+
+template <AllocationType T>
+struct DefaultDeviceContextType;
+
+template <>
+struct DefaultDeviceContextType<AllocationType::CPU> {
+  using TYPE = phi::CPUContext;
+};
+
+template <>
+struct DefaultDeviceContextType<AllocationType::GPU> {
+  using TYPE = phi::GPUContext;
+};
+
+/**
+ * The DeviceContextPool here is just a mirror of the DeviceContextPool in
+ * fluid, and does not manage the life cycle of the DeviceContext.
+ * It is mainly used for external custom operator calls and high-performance
+ * C++ APIs.
+ *
+ * Since DeviceContextPool in fluid is a global singleton, it always exists
+ * in program running, so DeviceContextPool here can always access the correct
+ * DeviceContext pointer.
+ *
+ * In order not to depend on the fluid's DeviceContextPool,
+ * the DeviceContextPool here needs to be initialized in the fluid, and cannot
+ * be initialized by itself.
+ */
+class DeviceContextPool {
+ public:
+  static DeviceContextPool& Instance();
+
+  const phi::DeviceContext* Get(const Place& place) const;
+
+  phi::DeviceContext* GetMutable(const Place& place);
+
+  template <AllocationType T>
+  const typename DefaultDeviceContextType<T>::TYPE* Get(
+      const Place& place) const {
+    return reinterpret_cast<const typename DefaultDeviceContextType<T>::TYPE*>(
+        Get(place));
+  }
+
+ private:
+  DeviceContextPool();
+  paddle::flat_hash_map<Place, const phi::DeviceContext*, Place::Hash>
+      context_map_;
+
+  DISABLE_COPY_AND_ASSIGN(DeviceContextPool);
+};
+
+}  // namespace experimental
+}  // namespace paddle

paddle/phi/api/lib/CMakeLists.txt

@@ -135,8 +135,9 @@ add_custom_command(
 
 cc_library(op_meta_info SRCS op_meta_info.cc DEPS phi_tensor_raw)
 cc_library(wrapped_infermeta SRCS ${wrapped_infermeta_source_file} DEPS phi)
+cc_library(context_pool SRCS context_pool.cc DEPS phi_context phi_enforce place)
 
-cc_library(kernel_dispatch SRCS kernel_dispatch.cc DEPS phi_tensor_raw phi_context kernel_factory)
+cc_library(kernel_dispatch SRCS kernel_dispatch.cc DEPS phi_tensor_raw phi_context kernel_factory context_pool)
 cc_library(api_gen_utils SRCS api_gen_utils.cc DEPS phi_tensor_raw selected_rows sparse_csr_tensor sparse_coo_tensor)
 cc_library(phi_data_transform SRCS data_transform.cc DEPS phi_tensor_raw transfer_layout_kernel cast_kernel data_device_transform)
 cc_library(api_custom_impl SRCS api_custom_impl.cc DEPS phi_tensor_raw phi kernel_dispatch api_gen_utils phi_data_transform)

paddle/phi/api/lib/context_pool.cc

@@ -0,0 +1,65 @@
+/* Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/phi/api/include/context_pool.h"
+
+#include "paddle/phi/backends/all_context.h"
+#include "paddle/phi/core/enforce.h"
+
+namespace paddle {
+namespace experimental {
+
+DeviceContextPool& DeviceContextPool::Instance() {
+  static DeviceContextPool g_device_context_pool;
+  return g_device_context_pool;
+}
+
+const phi::DeviceContext* DeviceContextPool::Get(const Place& place) const {
+  auto it = context_map_.find(place);
+  PADDLE_ENFORCE_NE(
+      it,
+      context_map_.end(),
+      phi::errors::NotFound("The DeviceContext of %s does not exists.", place));
+  return it->second;
+}
+
+phi::DeviceContext* DeviceContextPool::GetMutable(const Place& place) {
+  return const_cast<phi::DeviceContext*>(Get(place));
+}
+
+DeviceContextPool::DeviceContextPool() {
+  // We need to make sure that the correct value exists
+  // whenever we get the DeviceContext from DeviceContextPool
+  const auto& device_contexts =
+      paddle::platform::DeviceContextPool::Instance().device_contexts();
+  for (const auto& pair : device_contexts) {
+    // only get CPU and GPU DeviceContext now, add other DeviceContext type
+    // later if needed
+    if (platform::is_cpu_place(pair.first)
+#if defined(PADDLE_WITH_CUDA) || defined(PADDLE_WITH_HIP)
+        ||
+        platform::is_gpu_place(pair.first)) {
+#else
+            ) {
+#endif
+      const phi::DeviceContext* dev_ctx = pair.second.get().get();
+      VLOG(3) << "Init phi DeviceContextPool: insert {" << pair.first << ", "
+              << dev_ctx << "}";
+      context_map_[pair.first] = dev_ctx;
+    }
+  }
+}
+
+}  // namespace experimental
+}  // namespace paddle

paddle/phi/api/lib/kernel_dispatch.cc

@@ -14,6 +14,7 @@ limitations under the License. */
 
 #include "paddle/phi/api/lib/kernel_dispatch.h"
 
+#include "paddle/phi/api/include/context_pool.h"
 #include "paddle/phi/core/compat/convert_utils.h"
 
 namespace paddle {
@@ -52,8 +53,8 @@ std::size_t CountLeadingZeros(uint64_t val) {
 }  // namespace detail
 
 phi::DeviceContext* GetDeviceContextByBackend(phi::Backend backend) {
-  auto& pool = paddle::platform::DeviceContextPool::Instance();
-  return pool.Get(phi::TransToPhiPlace(backend));
+  auto& pool = paddle::experimental::DeviceContextPool::Instance();
+  return pool.GetMutable(phi::TransToPhiPlace(backend));
 }
 
 DataType ParseDataType(DataType dtype) { return dtype; }

paddle/phi/common/place.cc

@@ -92,4 +92,20 @@ std::string GetGlobalDeviceType(size_t device_type_id) {
   return global_registered_device_type[device_type_id];
 }
 
+constexpr static int kAllocationTypeBitLength = 8;
+constexpr static int kDeviceTypeIDBitLength = 8;
+constexpr static int kDeviceIDBitLength = 8;
+
+uint32_t Place::Hash::operator()(const Place &place) const {
+  uint32_t hash_value = 0;
+  // |----31-24------|-----23-16------|-----15-08----|---7-0----|
+  // | For extension | AllocationType | DeviceTypeID | DeviceID |
+  hash_value |= (static_cast<uint8_t>(place.alloc_type_)
+                 << (kDeviceIDBitLength + kDeviceTypeIDBitLength));
+  hash_value |=
+      (static_cast<uint8_t>(place.device_type_id_) << kDeviceIDBitLength);
+  hash_value |= static_cast<uint8_t>(place.device);
+  return hash_value;
+}
+
 }  // namespace phi

paddle/phi/common/place.h

@@ -73,31 +73,23 @@ class Place {
 
   std::string DebugString() const;
 
+  struct Hash {
+    // Note: Now the number of bits we need does not exceed 32 bits, so there is
+    // no need to use 64 bits. If needed in the future, it can be expanded,
+    // but now we don’t over-design.
+    uint32_t operator()(const Place& place) const;
+  };
+
+  uint32_t HashValue() const { return Hash()(*this); }
+
   inline bool operator==(const Place& rhs) const {
-    if (alloc_type_ != rhs.GetType()) {
-      return false;
-    }
-    if (alloc_type_ == AllocationType::CPU ||
-        alloc_type_ == AllocationType::GPUPINNED ||
-        alloc_type_ == AllocationType::NPUPINNED) {
-      return true;
-    }
-    if (alloc_type_ == AllocationType::CUSTOM) {
-      return device_type_id_ == rhs.device_type_id_ &&
-             device == rhs.GetDeviceId();
-    }
-    return device == rhs.GetDeviceId();
+    return HashValue() == rhs.HashValue();
+  }
+  inline bool operator!=(const Place& rhs) const {
+    return HashValue() != rhs.HashValue();
   }
-  inline bool operator!=(const Place& rhs) const { return !(*this == rhs); }
   inline bool operator<(const Place& rhs) const {
-    if (alloc_type_ != rhs.GetType()) {
-      return static_cast<int>(alloc_type_) < static_cast<int>(rhs.GetType());
-    }
-    if (alloc_type_ == AllocationType::CUSTOM &&
-        device_type_id_ != rhs.device_type_id_) {
-      return device_type_id_ < rhs.device_type_id_;
-    }
-    return device < rhs.GetDeviceId();
+    return HashValue() < rhs.HashValue();
   }
 
  public:
@@ -206,3 +198,10 @@ class CustomPlace : public Place {
 std::ostream& operator<<(std::ostream&, const Place&);
 
 }  // namespace phi
+
+namespace paddle {
+namespace experimental {
+using AllocationType = phi::AllocationType;
+using Place = phi::Place;
+}  // namespace experimental
+}  // namespace paddle