Add OpenVINO backend to pip wheel for Linux x86_64 (#18309)

.ci/scripts/wheel/pre_build_script.sh

@@ -62,3 +62,10 @@ if [[ "$(uname -s)" == "Linux" && "$(uname -m)" == "x86_64" ]]; then
   echo "QNN_SDK_ROOT=${QNN_SDK_ROOT}" >> "${GITHUB_ENV}"
   echo "QNN SDK downloaded to ${QNN_SDK_ROOT}"
 fi
+
+# Install OpenVINO Python package on Linux for wheel testing.
+# The backend itself has no build-time dependency (uses dlopen at runtime).
+if [[ "$(uname -s)" == "Linux" ]]; then
+  echo "Installing OpenVINO runtime for testing..."
+  pip install "openvino>=2025.1.0,<2026.0.0"
+fi

.ci/scripts/wheel/test_linux.py

@@ -24,6 +24,11 @@
         ), f"QnnBackend not found in registered backends: {registered}"
         print("✓ QnnBackend is registered")
 
+        assert (
+            "OpenvinoBackend" in registered
+        ), f"OpenvinoBackend not found in registered backends: {registered}"
+        print("✓ OpenvinoBackend is registered")
+
     test_base.run_tests(
         model_tests=[
             test_base.ModelTest(

.ci/scripts/wheel/test_linux_aarch64.py

@@ -12,6 +12,18 @@
     # coremltools does not support linux aarch64 yet and install from the source fails on runtime
     # https://github.com/apple/coremltools/issues/1254
     # https://github.com/apple/coremltools/issues/2195
+
+    from executorch.extension.pybindings.portable_lib import (
+        _get_registered_backend_names,
+    )
+
+    registered = _get_registered_backend_names()
+
+    assert (
+        "OpenvinoBackend" in registered
+    ), f"OpenvinoBackend not found in registered backends: {registered}"
+    print("✓ OpenvinoBackend is registered")
+
     test_base.run_tests(
         model_tests=[
             test_base.ModelTest(

README-wheel.md

@@ -14,6 +14,10 @@ to run ExecuTorch `.pte` files, with some restrictions:
 * Only the [XNNPACK backend delegate](docs/source/backends/xnnpack/xnnpack-overview.md) is linked into the prebuilt module.
 * \[macOS only] [Core ML](docs/source/backends/coreml/coreml-overview.md) and [MPS](docs/source/backends/mps/mps-overview.md) backend
   are also linked into the prebuilt module.
+* \[Linux x86_64] [QNN](docs/source/backends-qualcomm.md) backend is linked into the prebuilt module.
+* \[Linux] [OpenVINO](docs/source/build-run-openvino.md) backend is also linked into the
+  prebuilt module. OpenVINO requires the runtime to be installed separately:
+  `pip install executorch[openvino]`
 
 Please visit the [ExecuTorch website](https://pytorch.org/executorch) for
 tutorials and documentation. Here are some starting points:

backends/openvino/CMakeLists.txt

@@ -28,36 +28,32 @@ set(COMMON_INCLUDE_DIRS ${EXECUTORCH_ROOT}/..)
 # Include utility CMake scripts from ExecuteTorch
 include(${EXECUTORCH_ROOT}/tools/cmake/Utils.cmake)
 
-# Find OpenVINO libraries
-find_package(OpenVINO REQUIRED)
+# The backend resolves OpenVINO C API symbols via dlopen/dlsym at runtime, so
+# there is no build-time dependency on the OpenVINO SDK.
 
 # Define OpenVINO backend as a static library
-add_library(openvino_backend STATIC .)
+add_library(openvino_backend STATIC)
 
 # Enable exceptions and RTTI for OpenVINO backend
 target_compile_options(openvino_backend PRIVATE -frtti -fexceptions)
 
-# Include Executorch directories
-target_include_directories(openvino_backend PRIVATE ${COMMON_INCLUDE_DIRS})
-
-# Link OpenVINO and ExecuteTorch core libraries
-target_link_libraries(
-  openvino_backend PRIVATE openvino::runtime executorch_core
-)
-
 # Add source files for OpenVINO backend
 target_sources(
   openvino_backend
   PRIVATE ${CMAKE_CURRENT_LIST_DIR}/runtime/OpenvinoBackend.cpp
 )
 
+# Include Executorch directories
+target_include_directories(openvino_backend PRIVATE ${COMMON_INCLUDE_DIRS})
+
+# Link ExecuteTorch core and dynamic loading libraries
+target_link_libraries(openvino_backend PRIVATE executorch_core ${CMAKE_DL_LIBS})
+
 executorch_target_link_options_shared_lib(openvino_backend)
 
 # Install OpenVINO backend library to the lib directory
 install(
   TARGETS openvino_backend
   EXPORT ExecuTorchTargets
   DESTINATION ${CMAKE_INSTALL_LIBDIR}
-  INCLUDES
-  DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
 )

backends/openvino/README.md

@@ -12,6 +12,36 @@ OpenVINO backend supports the following hardware:
 
 For more information on the supported hardware, please refer to [OpenVINO System Requirements](https://docs.openvino.ai/2025/about-openvino/release-notes-openvino/system-requirements.html) page.
 
+## Quick Start (pip wheel)
+
+On Linux, the OpenVINO backend is included in the ExecuTorch pip wheel. Install the OpenVINO runtime to activate it:
+
+```bash
+pip install executorch[openvino]
+```
+
+Set the library path so the backend can find the OpenVINO runtime:
+
+```bash
+export LD_LIBRARY_PATH="$(python3 -c "import openvino, os; print(os.path.join(os.path.dirname(openvino.__file__), 'libs'))")${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}"
+```
+
+Or point to the library directly:
+
+```bash
+export OPENVINO_LIB_PATH=$(python3 -c "import openvino, os; print(os.path.join(os.path.dirname(openvino.__file__), 'libs', 'libopenvino_c.so'))")
+```
+
+Verify the backend is available:
+
+```python
+from executorch.extension.pybindings.portable_lib import (
+    _get_registered_backend_names,
+)
+print(_get_registered_backend_names())
+# Should include 'OpenvinoBackend'
+```
+
 ## Directory Structure
 
 ```
@@ -24,6 +54,7 @@ executorch
 │           ├── __init__.py
 │           └── quantizer.py
 │       ├── runtime
+│           ├── OpenvinoApi.h
 │           ├── OpenvinoBackend.cpp
 │           └── OpenvinoBackend.h
 │       ├── scripts

backends/openvino/runtime/OpenvinoApi.h

@@ -0,0 +1,133 @@
+/*
+ * Copyright (c) Intel Corporation
+ *
+ * Licensed under the BSD License (the "License"); you may not use this file
+ * except in compliance with the License. See the license file found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <dlfcn.h>
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+
+namespace executorch {
+namespace backends {
+namespace openvino {
+
+// Forward declarations matching the OpenVINO C API opaque types.
+// Only pointer types are used so struct layout is irrelevant.
+typedef struct ov_core ov_core_t;
+typedef struct ov_compiled_model ov_compiled_model_t;
+typedef struct ov_infer_request ov_infer_request_t;
+typedef struct ov_tensor ov_tensor_t;
+
+// Value types reproduced from openvino/c/ov_shape.h and ov_common.h.
+// These are stable C ABI — pinned via version constraint in pyproject.toml.
+typedef struct {
+  int64_t rank;
+  int64_t* dims;
+} ov_shape_t;
+
+typedef struct {
+  char** devices;
+  size_t size;
+} ov_available_devices_t;
+
+// Intentionally partial — only OV_STATUS_OK is needed for success checks.
+// The full enum is defined in openvino/c/ov_common.h.
+typedef enum {
+  OV_STATUS_OK = 0,
+  OV_STATUS_GENERAL_ERROR = -1,
+} ov_status_e;
+
+// Values aligned with ov::element::Type_t (sequential enum).
+typedef enum {
+  OV_ELEMENT_UNDEFINED = 0,
+  OV_ELEMENT_BOOLEAN = 1,
+  OV_ELEMENT_BF16 = 2,
+  OV_ELEMENT_F16 = 3,
+  OV_ELEMENT_F32 = 4,
+  OV_ELEMENT_F64 = 5,
+  OV_ELEMENT_I4 = 6,
+  OV_ELEMENT_I8 = 7,
+  OV_ELEMENT_I16 = 8,
+  OV_ELEMENT_I32 = 9,
+  OV_ELEMENT_I64 = 10,
+  OV_ELEMENT_U1 = 11,
+  OV_ELEMENT_U2 = 12,
+  OV_ELEMENT_U3 = 13,
+  OV_ELEMENT_U4 = 14,
+  OV_ELEMENT_U6 = 15,
+  OV_ELEMENT_U8 = 16,
+} ov_element_type_e;
+
+// Function pointer types for each OpenVINO C API function we use.
+using ov_core_create_fn = ov_status_e (*)(ov_core_t**);
+using ov_core_free_fn = void (*)(ov_core_t*);
+using ov_core_get_available_devices_fn =
+    ov_status_e (*)(const ov_core_t*, ov_available_devices_t*);
+using ov_available_devices_free_fn = void (*)(ov_available_devices_t*);
+using ov_core_import_model_fn = ov_status_e (*)(
+    const ov_core_t*,
+    const char*,
+    size_t,
+    const char*,
+    ov_compiled_model_t**);
+using ov_compiled_model_create_infer_request_fn =
+    ov_status_e (*)(const ov_compiled_model_t*, ov_infer_request_t**);
+using ov_compiled_model_inputs_size_fn =
+    ov_status_e (*)(const ov_compiled_model_t*, size_t*);
+using ov_compiled_model_outputs_size_fn =
+    ov_status_e (*)(const ov_compiled_model_t*, size_t*);
+using ov_compiled_model_free_fn = void (*)(ov_compiled_model_t*);
+using ov_infer_request_set_input_tensor_by_index_fn =
+    ov_status_e (*)(ov_infer_request_t*, size_t, const ov_tensor_t*);
+using ov_infer_request_set_output_tensor_by_index_fn =
+    ov_status_e (*)(ov_infer_request_t*, size_t, const ov_tensor_t*);
+using ov_infer_request_infer_fn = ov_status_e (*)(ov_infer_request_t*);
+using ov_infer_request_free_fn = void (*)(ov_infer_request_t*);
+using ov_tensor_create_from_host_ptr_fn =
+    ov_status_e (*)(ov_element_type_e, ov_shape_t, void*, ov_tensor_t**);
+using ov_tensor_free_fn = void (*)(ov_tensor_t*);
+using ov_shape_create_fn =
+    ov_status_e (*)(int64_t, const int64_t*, ov_shape_t*);
+using ov_shape_free_fn = ov_status_e (*)(ov_shape_t*);
+
+struct DlCloser {
+  void operator()(void* handle) {
+    if (handle) {
+      dlclose(handle);
+    }
+  }
+};
+using DlHandle = std::unique_ptr<void, DlCloser>;
+
+struct OpenvinoFunctions {
+  ov_core_create_fn core_create = nullptr;
+  ov_core_free_fn core_free = nullptr;
+  ov_core_get_available_devices_fn core_get_available_devices = nullptr;
+  ov_available_devices_free_fn available_devices_free = nullptr;
+  ov_core_import_model_fn core_import_model = nullptr;
+  ov_compiled_model_create_infer_request_fn
+      compiled_model_create_infer_request = nullptr;
+  ov_compiled_model_inputs_size_fn compiled_model_inputs_size = nullptr;
+  ov_compiled_model_outputs_size_fn compiled_model_outputs_size = nullptr;
+  ov_compiled_model_free_fn compiled_model_free = nullptr;
+  ov_infer_request_set_input_tensor_by_index_fn
+      infer_request_set_input_tensor_by_index = nullptr;
+  ov_infer_request_set_output_tensor_by_index_fn
+      infer_request_set_output_tensor_by_index = nullptr;
+  ov_infer_request_infer_fn infer_request_infer = nullptr;
+  ov_infer_request_free_fn infer_request_free = nullptr;
+  ov_tensor_create_from_host_ptr_fn tensor_create_from_host_ptr = nullptr;
+  ov_tensor_free_fn tensor_free = nullptr;
+  ov_shape_create_fn shape_create = nullptr;
+  ov_shape_free_fn shape_free = nullptr;
+};
+
+} // namespace openvino
+} // namespace backends
+} // namespace executorch