Expose get_num_threads via pybind

Differential Revision: D87510750

Pull Request resolved: #15944

Author: kimishpatel

extension/pybindings/portable_lib.py

@@ -65,6 +65,7 @@
     _load_program,  # noqa: F401
     _load_program_from_buffer,  # noqa: F401
     _reset_profile_results,  # noqa: F401
+    _threadpool_get_thread_count,  # noqa: F401
     _unsafe_reset_threadpool,  # noqa: F401
     BundledModule,  # noqa: F401
     ExecuTorchMethod,  # noqa: F401

extension/pybindings/pybindings.cpp

@@ -1558,6 +1558,13 @@ PYBIND11_MODULE(EXECUTORCH_PYTHON_MODULE_NAME, m) {
       },
       py::arg("num_threads"),
       call_guard);
+  m.def(
+      "_threadpool_get_thread_count",
+      []() {
+        return ::executorch::extension::threadpool::get_threadpool()
+            ->get_thread_count();
+      },
+      call_guard);
 
   py::class_<PyModule>(m, "ExecuTorchModule")
       .def(

extension/pybindings/pybindings.pyi

@@ -288,3 +288,12 @@ def _unsafe_reset_threadpool(num_threads: int) -> None:
         This API is experimental and subject to change without notice.
     """
     ...
+
+@experimental("This API is experimental and subject to change without notice.")
+def _threadpool_get_thread_count() -> int:
+    """
+    .. warning::
+
+        This API is experimental and subject to change without notice.
+    """
+    ...