gh-117657: Acquire a critical section around `SemLock.__{enter,exit}__` (#118812)

These methods are purely wrappers around `Semlock.{acquire,release}`,
which expect a critical section to be held.

diff --git a/Modules/_multiprocessing/clinic/semaphore.c.h b/Modules/_multiprocessing/clinic/semaphore.c.h
index 64e666b5af6f5bdec02920c9725b0ca826b15f41..512e5a016192fb0e6b141ca99f746960f1534410 100644 (file)
--- a/Modules/_multiprocessing/clinic/semaphore.c.h
+++ b/Modules/_multiprocessing/clinic/semaphore.c.h
@@ -473,7 +473,13 @@ _multiprocessing_SemLock___enter___impl(SemLockObject *self);
 static PyObject *
 _multiprocessing_SemLock___enter__(SemLockObject *self, PyObject *Py_UNUSED(ignored))
 {
-    return _multiprocessing_SemLock___enter___impl(self);
+    PyObject *return_value = NULL;
+
+    Py_BEGIN_CRITICAL_SECTION(self);
+    return_value = _multiprocessing_SemLock___enter___impl(self);
+    Py_END_CRITICAL_SECTION();
+
+    return return_value;
 }
 
 #endif /* defined(HAVE_MP_SEMAPHORE) */
@@ -518,7 +524,9 @@ _multiprocessing_SemLock___exit__(SemLockObject *self, PyObject *const *args, Py
     }
     exc_tb = args[2];
 skip_optional:
+    Py_BEGIN_CRITICAL_SECTION(self);
     return_value = _multiprocessing_SemLock___exit___impl(self, exc_type, exc_value, exc_tb);
+    Py_END_CRITICAL_SECTION();
 
 exit:
     return return_value;
@@ -565,4 +573,4 @@ exit:
 #ifndef _MULTIPROCESSING_SEMLOCK___EXIT___METHODDEF
     #define _MULTIPROCESSING_SEMLOCK___EXIT___METHODDEF
 #endif /* !defined(_MULTIPROCESSING_SEMLOCK___EXIT___METHODDEF) */
-/*[clinic end generated code: output=713b597256233716 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=dea36482d23a355f input=a9049054013a1b77]*/

diff --git a/Modules/_multiprocessing/semaphore.c b/Modules/_multiprocessing/semaphore.c
index 5bb055f501e35b10ff5f477ae4a124ef43faee3a..4de4ee6c78fbd1dbd8c2dee91ad4482c252c21b2 100644 (file)
--- a/Modules/_multiprocessing/semaphore.c
+++ b/Modules/_multiprocessing/semaphore.c
@@ -682,6 +682,7 @@ _multiprocessing_SemLock__after_fork_impl(SemLockObject *self)
 }
 
 /*[clinic input]
+@critical_section
 _multiprocessing.SemLock.__enter__
 
 Enter the semaphore/lock.
@@ -689,12 +690,13 @@ Enter the semaphore/lock.
 
 static PyObject *
 _multiprocessing_SemLock___enter___impl(SemLockObject *self)
-/*[clinic end generated code: output=beeb2f07c858511f input=c5e27d594284690b]*/
+/*[clinic end generated code: output=beeb2f07c858511f input=d35c9860992ee790]*/
 {
     return _multiprocessing_SemLock_acquire_impl(self, 1, Py_None);
 }
 
 /*[clinic input]
+@critical_section
 _multiprocessing.SemLock.__exit__
 
     exc_type: object = None
@@ -709,7 +711,7 @@ static PyObject *
 _multiprocessing_SemLock___exit___impl(SemLockObject *self,
                                        PyObject *exc_type,
                                        PyObject *exc_value, PyObject *exc_tb)
-/*[clinic end generated code: output=3b37c1a9f8b91a03 input=7d644b64a89903f8]*/
+/*[clinic end generated code: output=3b37c1a9f8b91a03 input=1610c8cc3e0e337e]*/
 {
     return _multiprocessing_SemLock_release_impl(self);
 }