Add Python 3.11 support

Backport of https://github.com/unbit/uwsgi/pull/2453

Resolves: rhbz#2099185

diff --git a/plugins/python/profiler.c b/plugins/python/profiler.c
index 92bc3da..2a7e1cc 100644
--- a/plugins/python/profiler.c
+++ b/plugins/python/profiler.c
@@ -13,6 +13,14 @@ int PyFrame_GetLineNumber(PyFrameObject *frame) {
 }
 #endif
 
+#if PY_VERSION_HEX < 0x030900B1
+PyCodeObject* PyFrame_GetCode(PyFrameObject *frame)
+{
+	Py_INCREF(frame->f_code);
+	return frame->f_code;
+}
+#endif
+
 #ifdef PYTHREE
 #undef PyString_AsString
 static char *PyString_AsString(PyObject *o) {
@@ -27,27 +35,32 @@ int uwsgi_python_profiler_call(PyObject *obj, PyFrameObject *frame, int what, Py
 	static uint64_t last_ts = 0;
         uint64_t now = uwsgi_micros();
         uint64_t delta = 0;
+	PyCodeObject *code;
 
 	switch(what) {
 		case PyTrace_CALL:
 			if (last_ts == 0) delta = 0;
                 	else delta = now - last_ts;
                 	last_ts = now;
+			code = PyFrame_GetCode(frame);
 			uwsgi_log("[uWSGI Python profiler %llu] CALL: %s (line %d) -> %s %d args, stacksize %d\n",
 				(unsigned long long) delta,
-				PyString_AsString(frame->f_code->co_filename),
+				PyString_AsString(code->co_filename),
 				PyFrame_GetLineNumber(frame),
-				PyString_AsString(frame->f_code->co_name), frame->f_code->co_argcount, frame->f_code->co_stacksize);
+				PyString_AsString(code->co_name), code->co_argcount, code->co_stacksize);
+			Py_DECREF(code);
 			break;
 		case PyTrace_C_CALL:
 			if (last_ts == 0) delta = 0;
                 	else delta = now - last_ts;
                 	last_ts = now;
+			code = PyFrame_GetCode(frame);
 			uwsgi_log("[uWSGI Python profiler %llu] C CALL: %s (line %d) -> %s %d args, stacksize %d\n",
 				(unsigned long long) delta,
-				PyString_AsString(frame->f_code->co_filename),
+				PyString_AsString(code->co_filename),
 				PyFrame_GetLineNumber(frame),
-				PyEval_GetFuncName(arg), frame->f_code->co_argcount, frame->f_code->co_stacksize);
+				PyEval_GetFuncName(arg), code->co_argcount, code->co_stacksize);
+			Py_DECREF(code);
 			break;
 	}
 
@@ -68,7 +81,9 @@ int uwsgi_python_tracer(PyObject *obj, PyFrameObject *frame, int what, PyObject
 			delta = now - last_ts;
 		}
 		last_ts = now;
-		uwsgi_log("[uWSGI Python profiler %llu] file %s line %d: %s argc:%d\n", (unsigned long long)delta,  PyString_AsString(frame->f_code->co_filename), PyFrame_GetLineNumber(frame), PyString_AsString(frame->f_code->co_name), frame->f_code->co_argcount);
+		PyCodeObject *code = PyFrame_GetCode(frame);
+		uwsgi_log("[uWSGI Python profiler %llu] file %s line %d: %s argc:%d\n", (unsigned long long)delta,  PyString_AsString(code->co_filename), PyFrame_GetLineNumber(frame), PyString_AsString(code->co_name), code->co_argcount);
+		Py_DECREF(code);
 	}
 
         return 0;
diff --git a/plugins/python/python_plugin.c b/plugins/python/python_plugin.c
index 6834f84..1d21c0d 100644
--- a/plugins/python/python_plugin.c
+++ b/plugins/python/python_plugin.c
@@ -1137,9 +1137,13 @@ void uwsgi_python_init_apps() {
 	}
 
 	// prepare for stack suspend/resume
-	if (uwsgi.async > 1) {
+	if (uwsgi.async > 0) {
+#ifdef UWSGI_PY311
+		up.current_recursion_remaining = uwsgi_malloc(sizeof(int)*uwsgi.async);
+#else
 		up.current_recursion_depth = uwsgi_malloc(sizeof(int)*uwsgi.async);
-        	up.current_frame = uwsgi_malloc(sizeof(struct _frame)*uwsgi.async);
+#endif
+		up.current_frame = uwsgi_malloc(sizeof(up.current_frame[0])*uwsgi.async);
 	}
 
         // setup app loaders
@@ -1530,12 +1534,22 @@ void uwsgi_python_suspend(struct wsgi_request *wsgi_req) {
 	PyGILState_Release(pgst);
 
 	if (wsgi_req) {
+#ifdef UWSGI_PY311
+		up.current_recursion_remaining[wsgi_req->async_id] = tstate->recursion_remaining;
+		up.current_frame[wsgi_req->async_id] = tstate->cframe;
+#else
 		up.current_recursion_depth[wsgi_req->async_id] = tstate->recursion_depth;
 		up.current_frame[wsgi_req->async_id] = tstate->frame;
+#endif
 	}
 	else {
+#ifdef UWSGI_PY311
+		up.current_main_recursion_remaining = tstate->recursion_remaining;
+		up.current_main_frame = tstate->cframe;
+#else
 		up.current_main_recursion_depth = tstate->recursion_depth;
 		up.current_main_frame = tstate->frame;
+#endif
 	}
 
 }
@@ -1763,12 +1777,22 @@ void uwsgi_python_resume(struct wsgi_request *wsgi_req) {
 	PyGILState_Release(pgst);
 
 	if (wsgi_req) {
+#ifdef UWSGI_PY311
+		tstate->recursion_remaining = up.current_recursion_remaining[wsgi_req->async_id];
+		tstate->cframe = up.current_frame[wsgi_req->async_id];
+#else
 		tstate->recursion_depth = up.current_recursion_depth[wsgi_req->async_id];
 		tstate->frame = up.current_frame[wsgi_req->async_id];
+#endif
 	}
 	else {
+#ifdef UWSGI_PY311
+		tstate->recursion_remaining = up.current_main_recursion_remaining;
+		tstate->cframe = up.current_main_frame;
+#else
 		tstate->recursion_depth = up.current_main_recursion_depth;
 		tstate->frame = up.current_main_frame;
+#endif
 	}
 
 }
diff --git a/plugins/python/uwsgi_python.h b/plugins/python/uwsgi_python.h
index 357d731..6c6f7a4 100644
--- a/plugins/python/uwsgi_python.h
+++ b/plugins/python/uwsgi_python.h
@@ -18,6 +18,10 @@
 #define UWSGI_PYTHON_OLD
 #endif
 
+#if (PY_VERSION_HEX >= 0x030b0000)
+#  define UWSGI_PY311
+#endif
+
 #if PY_MAJOR_VERSION == 2 && PY_MINOR_VERSION < 7
 #define HAS_NOT_PyMemoryView_FromBuffer
 #endif
@@ -165,11 +169,19 @@ struct uwsgi_python {
 
 	char *callable;
 
+#ifdef UWSGI_PY311
+	int *current_recursion_remaining;
+	_PyCFrame **current_frame;
+
+	int current_main_recursion_remaining;
+	_PyCFrame *current_main_frame;
+#else
 	int *current_recursion_depth;
 	struct _frame **current_frame;
 
 	int current_main_recursion_depth;
 	struct _frame *current_main_frame;
+#endif
 
 	void (*swap_ts)(struct wsgi_request *, struct uwsgi_app *);
 	void (*reset_ts)(struct wsgi_request *, struct uwsgi_app *);