From a6598575f4bc20f9a01c2bced2d0b1ff14d7576f Mon Sep 17 00:00:00 2001 From: Ralf Grosse-Kunstleve Date: Tue, 11 Jan 2022 19:34:38 +0100 Subject: [LLDB] Fix Python GIL-not-held issues The GIL must be held when calling any Python C API functions. In multithreaded applications that use callbacks this requirement can easily be violated by accident. A general tool to ensure GIL health is not available, but patching Python Py_INCREF to add an assert provides a basic health check: ``` +int PyGILState_Check(void); /* Include/internal/pystate.h */ + #define Py_INCREF(op) ( \ + assert(PyGILState_Check()), \ _Py_INC_REFTOTAL _Py_REF_DEBUG_COMMA \ ((PyObject *)(op))->ob_refcnt++) #define Py_DECREF(op) \ do { \ + assert(PyGILState_Check()); \ PyObject *_py_decref_tmp = (PyObject *)(op); \ if (_Py_DEC_REFTOTAL _Py_REF_DEBUG_COMMA \ --(_py_decref_tmp)->ob_refcnt != 0) \ ``` Adding this assertion causes around 50 test failures in LLDB. Adjusting the scope of things guarded by `py_lock` fixes them. More background: https://docs.python.org/3/glossary.html#term-global-interpreter-lock Patch by Ralf Grosse-Kunstleve Differential Revision: https://reviews.llvm.org/D114722 --- lldb/source/Plugins/ScriptInterpreter/Python/PythonDataObjects.cpp | 1 + 1 file changed, 1 insertion(+) (limited to 'lldb/source/Plugins/ScriptInterpreter/Python/PythonDataObjects.cpp') diff --git a/lldb/source/Plugins/ScriptInterpreter/Python/PythonDataObjects.cpp b/lldb/source/Plugins/ScriptInterpreter/Python/PythonDataObjects.cpp index 7c71c93..d68af67 100644 --- a/lldb/source/Plugins/ScriptInterpreter/Python/PythonDataObjects.cpp +++ b/lldb/source/Plugins/ScriptInterpreter/Python/PythonDataObjects.cpp @@ -257,6 +257,7 @@ PythonObject PythonObject::GetAttributeValue(llvm::StringRef attr) const { } StructuredData::ObjectSP PythonObject::CreateStructuredObject() const { + assert(PyGILState_Check()); switch (GetObjectType()) { case PyObjectType::Dictionary: return PythonDictionary(PyRefType::Borrowed, m_py_obj) -- cgit v1.1