Moved class out of function to hopefully enable pickling.

scalene/replacement_mp_lock.py

@@ -13,23 +13,12 @@
 # static PyObject * _multiprocessing_SemLock_acquire_impl(SemLockObject *self, int blocking, PyObject *timeout_obj)
 #
 # timeout_obj is parsed as a double
+
+from scalene.replacement_sem_lock import ReplacementSemLock
+
 @Scalene.shim
 def replacement_mp_semlock(scalene: Scalene) -> None:
-    class ReplacementSemLock(multiprocessing.synchronize.Lock):
-        def __enter__(self) -> bool:
-            timeout = sys.getswitchinterval()
-            tident = threading.get_ident()
-            while True:
-                scalene.set_thread_sleeping(tident)
-                acquired = self._semlock.acquire(timeout=timeout)  # type: ignore
-                scalene.reset_thread_sleeping(tident)
-                if acquired:
-                    return True
-
-        def __exit__(self, *args: Any) -> None:
-            super().__exit__(*args)
-
     ReplacementSemLock.__qualname__ = (
-        "replacement_mp_semlock.ReplacementSemLock"
+        "replacement_semlock.ReplacementSemLock"
     )
     multiprocessing.synchronize.Lock = ReplacementSemLock  # type: ignore

scalene/replacement_sem_lock.py

@@ -0,0 +1,23 @@
+import multiprocessing
+import sys
+import threading
+from scalene.scalene_profiler import Scalene
+from typing import Any
+
+def _recreate_replacement_sem_lock():
+    return ReplacementSemLock()
+
+class ReplacementSemLock(multiprocessing.synchronize.Lock):
+    def __enter__(self) -> bool:
+        timeout = sys.getswitchinterval()
+        tident = threading.get_ident()
+        while True:
+            Scalene.set_thread_sleeping(tident)
+            acquired = self._semlock.acquire(timeout=timeout)  # type: ignore
+            Scalene.reset_thread_sleeping(tident)
+            if acquired:
+                return True
+    def __exit__(self, *args: Any) -> None:
+        super().__exit__(*args)
+    def __reduce__(self):
+        return (_recreate_replacement_sem_lock, ())