unsigned long long race

Author: dpdani

Include/cpython/pyatomic.h

@@ -529,6 +529,10 @@ _Py_atomic_store_double_release(double *obj, double value);
 static inline void
 _Py_atomic_store_llong_release(long long *obj, long long value);
 
+static inline void
+_Py_atomic_store_ullong_release(unsigned long long *obj,
+                                unsigned long long value);
+
 static inline int
 _Py_atomic_load_int_acquire(const int *obj);
 

Include/cpython/pyatomic_gcc.h

@@ -576,6 +576,11 @@ static inline void
 _Py_atomic_store_llong_release(long long *obj, long long value)
 { __atomic_store_n(obj, value, __ATOMIC_RELEASE); }
 
+static inline void
+_Py_atomic_store_ullong_release(unsigned long long *obj,
+                                unsigned long long value)
+{ __atomic_store_n(obj, value, __ATOMIC_RELEASE); }
+
 static inline void
 _Py_atomic_store_ssize_release(Py_ssize_t *obj, Py_ssize_t value)
 { __atomic_store_n(obj, value, __ATOMIC_RELEASE); }

Include/cpython/pyatomic_msc.h

@@ -1129,6 +1129,19 @@ _Py_atomic_store_llong_release(long long *obj, long long value)
 #endif
 }
 
+static inline void
+_Py_atomic_store_ullong_release(unsigned long long *obj, unsigned long long value)
+{
+#if defined(_M_X64) || defined(_M_IX86)
+    *(unsigned long long volatile *)obj = value;
+#elif defined(_M_ARM64)
+    _Py_atomic_ASSERT_ARG_TYPE(unsigned __int128);
+    __stlr128((unsigned __int128 volatile *)obj, (unsigned __int128)value);
+#else
+#  error "no implementation of _Py_atomic_store_ullong_release"
+#endif
+}
+
 static inline void
 _Py_atomic_store_ssize_release(Py_ssize_t *obj, Py_ssize_t value)
 {

Include/cpython/pyatomic_std.h

@@ -1031,6 +1031,15 @@ _Py_atomic_store_llong_release(long long *obj, long long value)
                           memory_order_release);
 }
 
+static inline void
+_Py_atomic_store_ullong_release(unsigned long long *obj,
+                                unsigned long long value)
+{
+    _Py_USING_STD;
+    atomic_store_explicit((_Atomic(unsigned long long)*)obj, value,
+                          memory_order_release);
+}
+
 static inline void
 _Py_atomic_store_ssize_release(Py_ssize_t *obj, Py_ssize_t value)
 {

Include/internal/pycore_pyatomic_ft_wrappers.h

@@ -105,6 +105,10 @@ extern "C" {
     _Py_atomic_store_llong_release(&value, new_value)
 #define FT_ATOMIC_LOAD_LLONG_RELAXED(value) \
     _Py_atomic_load_llong_relaxed(&value)
+#define FT_ATOMIC_STORE_ULLONG_RELEASE(value, new_value) \
+    _Py_atomic_store_ullong_release(&value, new_value)
+#define FT_ATOMIC_LOAD_ULLONG_RELAXED(value) \
+    _Py_atomic_load_ullong_relaxed(&value)
 
 #else
 #define FT_ATOMIC_LOAD_PTR(value) value
@@ -150,6 +154,8 @@ extern "C" {
 #define FT_ATOMIC_STORE_DOUBLE_RELEASE(value, new_value) value = new_value
 #define FT_ATOMIC_LOAD_LLONG_RELAXED(value) value
 #define FT_ATOMIC_STORE_LLONG_RELEASE(value, new_value) value = new_value
+#define FT_ATOMIC_LOAD_ULLONG_RELAXED(value) value
+#define FT_ATOMIC_STORE_ULLONG_RELEASE(value, new_value) value = new_value
 
 #endif
 

Python/structmember.c

@@ -110,7 +110,7 @@ PyMember_GetOne(const char *obj_addr, PyMemberDef *l)
         v = PyLong_FromLongLong(FT_ATOMIC_LOAD_LLONG_RELAXED(*(long long *)addr));
         break;
     case Py_T_ULONGLONG:
-        v = PyLong_FromUnsignedLongLong(*(unsigned long long *)addr);
+        v = PyLong_FromUnsignedLongLong(FT_ATOMIC_LOAD_ULLONG_RELAXED(*(unsigned long long *)addr));
         break;
     case _Py_T_NONE:
         // doesn't require free-threading code path
@@ -346,7 +346,7 @@ PyMember_SetOne(char *addr, PyMemberDef *l, PyObject *v)
             if (long_val == -1 && PyErr_Occurred()) {
                 return -1;
             }
-            *(unsigned long long *)addr = (unsigned long long)(long long)long_val;
+            FT_ATOMIC_STORE_ULLONG_RELEASE(*(unsigned long long *)addr, (unsigned long long)(long long)long_val);
             WARN("Writing negative value into unsigned field");
         }
         else {
@@ -355,7 +355,7 @@ PyMember_SetOne(char *addr, PyMemberDef *l, PyObject *v)
             if (ulonglong_val == (unsigned long long)-1 && PyErr_Occurred()) {
                 return -1;
             }
-            *(unsigned long long*)addr = ulonglong_val;
+            FT_ATOMIC_STORE_ULLONG_RELEASE(*(unsigned long long *)addr, ulonglong_val);
         }
         break;
     }