Fix TorchRec inference solution with updated torch.fx + TorchScript Solution (#2101)

Summary:
Previously, the TorchRec inference solution used torch.deploy, which isn't supported, and the solution itself was outdated and broken. This PR revamps the inference example with Torch.FX and TorchScript, which more accurately represents what is used in production for RecSys currently. Furthermore, the example was constructed with simplicity as the top priority, with fewer package requirements and steps to run. This is the first iteration of the inference example, with more to come!

Pull Request resolved: #2101

Differential Revision: D58478461

Pulled By: PaulZhang12

Author: PaulZhang12

examples/inference/README.md renamed to examples/inference_legacy/README.md

@@ -4,110 +4,60 @@
 # This source code is licensed under the BSD-style license found in the
 # LICENSE file in the root directory of this source tree.
 
-cmake_minimum_required(VERSION 3.13 FATAL_ERROR)
-project(inference)
+cmake_minimum_required(VERSION 3.8)
 
-# This step is crucial to ensure that the
-# _REFLECTION, _GRPC_GRPCPP and _PROTOBUF_LIBPROTOBUF variables are set.
-# e.g. ~/gprc/examples/cpp/cmake/common.cmake
-include(${GRPC_COMMON_CMAKE_PATH}/common.cmake)
+project(inference C CXX)
 
+include(/home/paulzhan/grpc/examples/cpp/cmake/common.cmake)
 
-# abi and other flags
 
-if(DEFINED GLIBCXX_USE_CXX11_ABI)
-  if(${GLIBCXX_USE_CXX11_ABI} EQUAL 1)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_GLIBCXX_USE_CXX11_ABI=1")
-    set(TORCH_CXX_FLAGS "-D_GLIBCXX_USE_CXX11_ABI=1")
-  endif()
-endif()
+# Proto file
+get_filename_component(hw_proto "/home/paulzhan/torchrec/torchrec/inference/protos/predictor.proto" ABSOLUTE)
+get_filename_component(hw_proto_path "${hw_proto}" PATH)
 
-# keep it static for now since folly-shared version is broken
-# set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC")
-# set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fPIC")
+# Generated sources
+set(hw_proto_srcs "${CMAKE_CURRENT_BINARY_DIR}/predictor.pb.cc")
+set(hw_proto_hdrs "${CMAKE_CURRENT_BINARY_DIR}/predictor.pb.h")
+set(hw_grpc_srcs "${CMAKE_CURRENT_BINARY_DIR}/predictor.grpc.pb.cc")
+set(hw_grpc_hdrs "${CMAKE_CURRENT_BINARY_DIR}/predictor.grpc.pb.h")
+add_custom_command(
+      OUTPUT "${hw_proto_srcs}" "${hw_proto_hdrs}" "${hw_grpc_srcs}" "${hw_grpc_hdrs}"
+      COMMAND ${_PROTOBUF_PROTOC}
+      ARGS --grpc_out "${CMAKE_CURRENT_BINARY_DIR}"
+        --cpp_out "${CMAKE_CURRENT_BINARY_DIR}"
+        -I "${hw_proto_path}"
+        --plugin=protoc-gen-grpc="${_GRPC_CPP_PLUGIN_EXECUTABLE}"
+        "${hw_proto}"
+      DEPENDS "${hw_proto}")
 
-# dependencies
-find_package(Boost REQUIRED)
-find_package(Torch REQUIRED)
-find_package(folly REQUIRED)
-find_package(gflags REQUIRED)
-
-include_directories(${Torch_INCLUDE_DIRS})
-include_directories(${folly_INCLUDE_DIRS})
-include_directories(${PYTORCH_FMT_INCLUDE_PATH})
+# Include generated *.pb.h files
+include_directories("${CMAKE_CURRENT_BINARY_DIR}")
 
 set(CMAKE_CXX_STANDARD 17)
 
-# torch deploy library
-add_library(torch_deploy_internal STATIC
-    ${DEPLOY_INTERPRETER_PATH}/libtorch_deployinterpreter.o
-    ${DEPLOY_SRC_PATH}/deploy.cpp
-    ${DEPLOY_SRC_PATH}/loader.cpp
-    ${DEPLOY_SRC_PATH}/path_environment.cpp
-    ${DEPLOY_SRC_PATH}/elf_file.cpp)
-
-# For python builtins. caffe2_interface_library properly
-# makes use of the --whole-archive option.
-target_link_libraries(torch_deploy_internal PRIVATE
-  crypt pthread dl util m z ffi lzma readline nsl ncursesw panelw
-)
-target_link_libraries(torch_deploy_internal
-  PUBLIC shm torch ${PYTORCH_LIB_FMT}
-)
-caffe2_interface_library(torch_deploy_internal torch_deploy)
-
-# inference library
-
-# for our own header files
-include_directories(include/)
-include_directories(gen/)
-
-# define our library target
-add_library(inference STATIC
-  src/Batching.cpp
-  src/BatchingQueue.cpp
-  src/GPUExecutor.cpp
-  src/ResultSplit.cpp
-  src/Exception.cpp
-  src/ResourceManager.cpp
-)
-
-# -rdynamic is needed to link against the static library
-target_link_libraries(inference "-Wl,--no-as-needed -rdynamic"
-  dl torch_deploy "${TORCH_LIBRARIES}" ${FBGEMM_LIB} ${FOLLY_LIBRARIES}
-)
-
-# for generated protobuf
-
-# grpc headers. e.g. ~/.local/include
-include_directories(${GRPC_HEADER_INCLUDE_PATH})
-
-set(pred_grpc_srcs "gen/torchrec/inference/predictor.grpc.pb.cc")
-set(pred_grpc_hdrs "gen/torchrec/inference/predictor.grpc.pb.h")
-set(pred_proto_srcs "gen/torchrec/inference/predictor.pb.cc")
-set(pred_proto_hdrs "gen/torchrec/inference/predictor.pb.h")
+# Torch + FBGEMM
+find_package(Torch REQUIRED)
+add_library( fbgemm SHARED IMPORTED GLOBAL )
+set_target_properties(fbgemm PROPERTIES IMPORTED_LOCATION ${FBGEMM_LIB})
 
-add_library(pred_grpc_proto STATIC
-  ${pred_grpc_srcs}
-  ${pred_grpc_hdrs}
-  ${pred_proto_srcs}
-  ${pred_proto_hdrs})
 
-target_link_libraries(pred_grpc_proto
+add_library(hw_grpc_proto STATIC
+  ${hw_grpc_srcs}
+  ${hw_grpc_hdrs}
+  ${hw_proto_srcs}
+  ${hw_proto_hdrs})
+target_link_libraries(hw_grpc_proto
   ${_REFLECTION}
   ${_GRPC_GRPCPP}
   ${_PROTOBUF_LIBPROTOBUF})
 
-# server
+# Targets greeter_[async_](client|server)
 add_executable(server server.cpp)
 target_link_libraries(server
-  inference
-  torch_deploy
-  pred_grpc_proto
   "${TORCH_LIBRARIES}"
-  ${FOLLY_LIBRARIES}
-  ${PYTORCH_LIB_FMT}
-  ${FBGEMM_LIB}
+  fbgemm
+  hw_grpc_proto
   ${_REFLECTION}
   ${_GRPC_GRPCPP}
-  ${_PROTOBUF_LIBPROTOBUF})
+  ${_PROTOBUF_LIBPROTOBUF}
+)