feat: Makefile for trtorchrt.so example

Signed-off-by: Naren Dasan <naren@narendasan.com>
Signed-off-by: Naren Dasan <narens@nvidia.com>

.gitignore

@@ -40,4 +40,7 @@ py/wheelhouse
 py/.eggs
 notebooks/.ipynb_checkpoints/
 *.cache
-tests/py/data
+tests/py/data
+examples/**/deps/**/*
+!examples/**/deps/.gitkeep
+examples/trtorchrt_example/trtorchrt_example

core/plugins/README.md

@@ -6,7 +6,7 @@ On a high level, TRTorch plugin library interface does the following :
 
 - Uses TensorRT plugin registry as the main data structure to access all plugins.
 
-- Automatically registers TensorRT plugins with empty namepsace.  
+- Automatically registers TensorRT plugins with empty namepsace.
 
 - Automatically registers TRTorch plugins with `"trtorch"` namespace.
 
@@ -37,4 +37,4 @@ If you'd like to compile your plugin with TRTorch,
 
 Once you've completed the above steps, upon successful compilation of TRTorch library, your plugin should be available in  `libtrtorch_plugins.so`.
 
-A sample runtime application on how to run a network with plugins can be found <a href="https://github.com/NVIDIA/TRTorch/tree/master/examples/sample_rt_app" >here</a>
+A sample runtime application on how to run a network with plugins can be found <a href="https://github.com/NVIDIA/TRTorch/tree/master/examples/trtorchrt_example" >here</a>

docsrc/tutorials/runtime.rst

@@ -22,4 +22,15 @@ link ``libtrtorchrt.so`` in your deployment programs or use ``DL_OPEN`` or ``LD_
 you can load the runtime with ``torch.ops.load_library("libtrtorchrt.so")``. You can then continue to use
 programs just as you would otherwise via PyTorch API.
 
-.. note:: If you are using the standard distribution of PyTorch in Python on x86, likely you will need the pre-cxx11-abi variant of ``libtrtorchrt.so``, check :ref:`Installation` documentation for more details.
+.. note:: If you are using the standard distribution of PyTorch in Python on x86, likely you will need the pre-cxx11-abi variant of ``libtrtorchrt.so``, check :ref:`Installation` documentation for more details.
+
+.. note:: If you are linking ``libtrtorchrt.so``, likely using the following flags will help ``-Wl,--no-as-needed -ltrtorchrt -Wl,--as-needed`` as theres no direct symbol dependency to anything in the TRTorch runtime for most TRTorch runtime applications
+
+An example of how to use ``libtrtorchrt.so`` can be found here: https://github.com/NVIDIA/TRTorch/tree/master/examples/trtorchrt_example
+
+Plugin Library
+---------------
+
+In the case you use TRTorch as a converter to a TensorRT engine and your engine uses plugins provided by TRTorch, TRTorch
+ships the library ``libtrtorch_plugins.so`` which contains the implementation of the TensorRT plugins used by TRTorch during
+compilation. This library can be ``DL_OPEN`` or ``LD_PRELOAD`` similar to other TensorRT plugin libraries.

examples/trtorchrt_example/BUILD

@@ -0,0 +1,14 @@
+package(default_visibility = ["//visibility:public"])
+
+cc_binary(
+    name = "trtorchrt_example",
+    srcs = [
+        "main.cpp"
+    ],
+    deps = [
+        "//core/runtime:runtime",
+        "@libtorch//:libtorch",
+        "@libtorch//:caffe2",
+        "@tensorrt//:nvinfer",
+    ],
+)

examples/trtorchrt_example/Makefile

@@ -0,0 +1,14 @@
+CXX=g++
+DEP_DIR=$(PWD)/deps
+INCLUDE_DIRS=-I$(DEP_DIR)/libtorch/include -I$(DEP_DIR)/trtorch/include
+LIB_DIRS=-L$(DEP_DIR)/trtorch/lib -L$(DEP_DIR)/libtorch/lib # -Wl,-rpath $(DEP_DIR)/tensorrt/lib -Wl,-rpath $(DEP_DIR)/cudnn/lib64
+LIBS=-Wl,--no-as-needed -ltrtorchrt -Wl,--as-needed -ltorch -ltorch_cuda -ltorch_cpu -ltorch_global_deps -lbackend_with_compiler -lc10 -lc10_cuda
+SRCS=main.cpp
+
+TARGET=trtorchrt_example
+
+$(TARGET):
+	$(CXX) $(SRCS) $(INCLUDE_DIRS) $(LIB_DIRS) $(LIBS) -o $(TARGET)
+
+clean:
+	$(RM) $(TARGET)

examples/trtorchrt_example/README.md

@@ -0,0 +1,53 @@
+# trtorchrt_example
+
+## Sample application which uses TRTorch runtime library and plugin library.
+
+This sample is a demonstration on how to use TRTorch runtime library `libtrtorchrt.so` along with plugin library `libtrtorch_plugins.so`
+
+In this demo, we convert two models `ConvGelu` and `Norm` to TensorRT using TRTorch python API and perform inference using `samplertapp`. In these models, `Gelu` and `Norm` layer are expressed as plugins in the network.
+
+### Generating Torch script modules with TRT Engines
+
+The following command will generate `conv_gelu.jit` and `norm.jit` torchscript modules which contain TensorRT engines.
+
+```sh
+python network.py
+```
+
+### `trtorchrt_example`
+The main goal is to use TRTorch runtime library `libtrtorchrt.so`, a lightweight library sufficient enough to deploy your Torchscript programs containing TRT engines.
+
+1) Download releases of LibTorch and TRTorch from https://pytorch.org and the TRTorch github repo and unpack both in the deps directory.
+
+```sh
+cd examples/trtorchrt_example/deps
+// Download latest TRTorch release tar file (libtrtorch.tar.gz) from https://github.com/NVIDIA/TRTorch/releases
+tar -xvzf libtrtorch.tar.gz
+unzip libtorch-cxx11-abi-shared-with-deps-1.9.0+cu111.zip
+```
+
+> If cuDNN and TensorRT are not installed on your system / in your LD_LIBRARY_PATH then do the following as well
+
+```sh
+cd deps
+mkdir cudnn && tar -xvzf <cuDNN TARBALL> --directory cudnn --strip-components=1
+mkdir tensorrt && tar -xvzf <TensorRT TARBALL> --directory tensorrt --strip-components=1
+cd ..
+export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$(pwd)/deps/trtorch/lib:$(pwd)/deps/libtorch/lib:$(pwd)/deps/tensorrt/lib:$(pwd)/deps/cudnn/lib64:/usr/local/cuda/lib
+```
+
+This gives maximum compatibility with system configurations for running this example but in general you are better off adding `-Wl,-rpath $(DEP_DIR)/tensorrt/lib -Wl,-rpath $(DEP_DIR)/cudnn/lib64` to your linking command for actual applications
+
+ 2) Build and run `trtorchrt_example`
+
+​     `trtorchrt_example` is a binary which loads the torchscript modules `conv_gelu.jit` or `norm.jit` and runs the TRT engines on a random input using TRTorch runtime components. Checkout the `main.cpp` and `Makefile ` file for necessary code and compilation dependencies.
+
+To build and run the app
+
+```sh
+cd examples/trtorchrt_example
+make
+# If paths are different than the ones below, change as necessary
+export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$(pwd)/deps/trtorch/lib:$(pwd)/deps/libtorch/lib:$(pwd)/deps/tensorrt/lib:$(pwd)/deps/cudnn/lib64:/usr/local/cuda/lib
+./trtorchrt_example $PWD/examples/trtorchrt_example/norm.jit
+```