From 9b7c1b00c87c677aeb88b7c0f359a8cdfdf0b12e Mon Sep 17 00:00:00 2001
From: Peter Bierma <zintensitydev@gmail.com>
Date: Thu, 23 Jul 2026 13:26:26 -0400
Subject: [PATCH] Eagerly initialize audit hooks.

---
 Include/internal/pycore_interp_structs.h |  1 -
 Python/pystate.c                         |  1 -
 Python/sysmodule.c                       | 37 ++++++++++--------------
 3 files changed, 16 insertions(+), 23 deletions(-)

diff --git a/Include/internal/pycore_interp_structs.h b/Include/internal/pycore_interp_structs.h
index 3d577ff717cc6e..0623adce693d46 100644
--- a/Include/internal/pycore_interp_structs.h
+++ b/Include/internal/pycore_interp_structs.h
@@ -977,7 +977,6 @@ struct _is {
     struct _obmalloc_state *obmalloc;
 
     PyObject *audit_hooks;
-    PyMutex audit_hooks_mutex;
     PyType_WatchCallback type_watchers[TYPE_MAX_WATCHERS];
     PyCode_WatchCallback code_watchers[CODE_MAX_WATCHERS];
     PyContext_WatchCallback context_watchers[CONTEXT_MAX_WATCHERS];
diff --git a/Python/pystate.c b/Python/pystate.c
index b6c34552e94337..d10b38def32911 100644
--- a/Python/pystate.c
+++ b/Python/pystate.c
@@ -578,7 +578,6 @@ init_interpreter(PyInterpreterState *interp,
     llist_init(&interp->mem_free_queue.head);
     llist_init(&interp->asyncio_tasks_head);
     interp->asyncio_tasks_lock = (PyMutex){0};
-    interp->audit_hooks_mutex = (PyMutex){0};
     for (int i = 0; i < _PY_MONITORING_UNGROUPED_EVENTS; i++) {
         interp->monitors.tools[i] = 0;
     }
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index 207ccbce41d71d..2625830cfc6b1c 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -235,8 +235,12 @@ should_audit(PyInterpreterState *interp)
     if (!interp) {
         return 0;
     }
+    // interp->audit_hooks can only ever be NULL very early during initialization
+    // or very late during finalization.
+    int interp_has_audit_hooks = (interp->audit_hooks != NULL
+                                  && PyList_GET_SIZE(interp->audit_hooks) > 0);
     return (interp->runtime->audit_hooks.head
-            || FT_ATOMIC_LOAD_PTR_ACQUIRE(interp->audit_hooks)
+            || interp_has_audit_hooks
             || PyDTrace_AUDIT_ENABLED());
 }
 
@@ -306,8 +310,9 @@ sys_audit_tstate(PyThreadState *ts, const char *event,
     }
 
     /* Call interpreter hooks */
-    PyObject *audit_hooks = FT_ATOMIC_LOAD_PTR_ACQUIRE(is->audit_hooks);
-    if (audit_hooks) {
+    PyObject *audit_hooks = is->audit_hooks;
+    assert(audit_hooks != NULL);
+    if (PyList_GET_SIZE(audit_hooks) > 0) {
         eventName = PyUnicode_FromString(event);
         if (!eventName) {
             goto exit;
@@ -537,29 +542,13 @@ sys_addaudithook_impl(PyObject *module, PyObject *hook)
     }
 
     PyInterpreterState *interp = tstate->interp;
-    PyMutex mutex = interp->audit_hooks_mutex;
-    PyMutex_Lock(&mutex);
-
-    if (interp->audit_hooks == NULL) {
-        PyObject *new_list = PyList_New(0);
-        if (new_list == NULL) {
-            goto error;
-        }
-        /* Avoid having our list of hooks show up in the GC module */
-        PyObject_GC_UnTrack(new_list);
-        FT_ATOMIC_STORE_PTR_RELEASE(interp->audit_hooks, new_list);
-    }
 
+    assert(interp->audit_hooks != NULL);
     if (PyList_Append(interp->audit_hooks, hook) < 0) {
-        goto error;
+        return NULL;
     }
 
-    PyMutex_Unlock(&mutex);
     Py_RETURN_NONE;
-
-error:
-    PyMutex_Unlock(&mutex);
-    return NULL;
 }
 
 /*[clinic input]
@@ -4323,6 +4312,12 @@ _PySys_Create(PyThreadState *tstate, PyObject **sysmod_p)
 
     PyInterpreterState *interp = tstate->interp;
 
+    PyObject *audit_hooks = PyList_New(0);
+    if (audit_hooks == NULL) {
+        goto error;
+    }
+    interp->audit_hooks = audit_hooks;
+
     PyObject *modules = _PyImport_InitModules(interp);
     if (modules == NULL) {
         goto error;