gh-159645: Fix --async-aware profiles showing event loop frames under tasks

Author: deadlovelll

Lib/test/test_external_inspection.py

@@ -1,4 +1,5 @@
 import asyncio
+import collections.abc
 import unittest
 import os
 import textwrap
@@ -614,6 +615,54 @@ async def main():
         stacks = self._extract_coroutine_funcnames(asyncio.run(main()))
         self.assertEqual(stacks["consumer"], ["consumer"])
 
+    @skip_if_not_supported
+    def test_running_task_stack_between_steps(self):
+        # gh-159645
+        traces = []
+
+        class Loop(asyncio.SelectorEventLoop):
+            def call_soon(self, *args, **kwargs):
+                if asyncio.current_task(self) is not None:
+                    unwinder = RemoteUnwinder(os.getpid())
+                    traces.append(unwinder.get_async_stack_trace())
+                return super().call_soon(*args, **kwargs)
+
+        async def child():
+            await asyncio.sleep(0)
+
+        async def main():
+            await asyncio.create_task(child(), name="child")
+
+        asyncio.run(main(), loop_factory=Loop)
+        stacks = [list(self._extract_coroutine_funcnames(trace).values())
+                  for trace in traces]
+        self.assertIn([["sleep", "child"], ["main"]], stacks)
+        self.assertIn([[], ["main"]], stacks)
+
+    @skip_if_not_supported
+    def test_running_task_with_non_native_coroutine(self):
+        # gh-159645
+        class Wrapper(collections.abc.Coroutine):
+            def __init__(self, coro):
+                self._coro = coro
+            def send(self, value):
+                return self._coro.send(value)
+            def throw(self, *args):
+                return self._coro.throw(*args)
+            def close(self):
+                return self._coro.close()
+            def __await__(self):
+                return self._coro.__await__()
+
+        async def inner():
+            return RemoteUnwinder(os.getpid()).get_async_stack_trace()
+
+        async def main():
+            return await asyncio.create_task(Wrapper(inner()), name="wrapper")
+
+        stacks = self._extract_coroutine_funcnames(asyncio.run(main()))
+        self.assertEqual(stacks["wrapper"], [])
+
     @skip_if_not_supported
     @unittest.skipIf(
         sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,

Misc/NEWS.d/next/Library/2026-10-18-19-18-20.gh-issue-159645.IOXcpT.rst

@@ -0,0 +1,2 @@
+Fix :mod:profiling.sampling --async-aware profiles showing event loop frames
+under tasks. Patch by Timofei Ivankov.

Modules/_remote_debugging/asyncio.c

@@ -765,6 +765,24 @@ get_task_frame(RemoteUnwinderObject *unwinder, uintptr_t task_addr, uintptr_t *f
     if (get_coro_like_address(unwinder, running_coro_addr, &running_coro_addr) < 0) {
         return -1;
     }
+    if (running_coro_addr == 0) {
+        *frame_addr = 0;
+        return 0;
+    }
+
+    int8_t frame_state;
+    if (_Py_RemoteDebug_PagedReadRemoteMemory(
+            &unwinder->handle,
+            running_coro_addr + (uintptr_t)unwinder->debug_offsets.gen_object.gi_frame_state,
+            sizeof(frame_state),
+            &frame_state) < 0) {
+        set_exception_cause(unwinder, PyExc_RuntimeError, "Running task coro frame state read failed");
+        return -1;
+    }
+    if (frame_state != FRAME_EXECUTING) {
+        *frame_addr = 0;
+        return 0;
+    }
 
     *frame_addr = running_coro_addr + (uintptr_t)unwinder->debug_offsets.gen_object.gi_iframe;
     return 0;
@@ -972,6 +990,11 @@ process_running_task_chain(
         return -1;
     }
 
+    // gh-159645: the coroutine isn't running, so keep its await chain.
+    if (running_task_frame == 0) {
+        return process_task_waiters(unwinder, result);
+    }
+
     // Get the chain from the current frame to this task
     PyObject *coro_chain = PyStructSequence_GET_ITEM(task_info, 2);
     assert(coro_chain != NULL);