Rooba
/
cpython
mirror of https://github.com/python/cpython.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

GH-127705: Add debug mode for `_PyStackRef`s inspired by HPy debug mode (GH-128121)

This commit is contained in:
Mark Shannon 2024-12-20 16:52:20 +00:00 committed by GitHub
parent 78ffba4221
commit 128cc47fbd
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
12 changed files with 395 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
Include/internal/pycore_interp.h
View File

@ -34,6 +34,7 @@ extern "C" {
#include "pycore_optimizer.h" // _PyOptimizerObject
#include "pycore_obmalloc.h" // struct _obmalloc_state
#include "pycore_qsbr.h" // struct _qsbr_state
#include "pycore_stackref.h" // Py_STACKREF_DEBUG
#include "pycore_tstate.h" // _PyThreadStateImpl
#include "pycore_tuple.h" // struct _Py_tuple_state
#include "pycore_uniqueid.h" // struct _Py_unique_id_pool
@ -285,6 +286,11 @@ struct _is {
_PyThreadStateImpl _initial_thread;
// _initial_thread should be the last field of PyInterpreterState.
// See https://github.com/python/cpython/issues/127117.
#if !defined(Py_GIL_DISABLED) && defined(Py_STACKREF_DEBUG)
uint64_t next_stackref;
_Py_hashtable_t *stackref_debug_table;
#endif
};

113
Include/internal/pycore_stackref.h
View File

@ -4,6 +4,9 @@
extern "C" {
#endif
// Define this to get precise tracking of stackrefs.
// #define Py_STACKREF_DEBUG 1
#ifndef Py_BUILD_CORE
# error "this header requires Py_BUILD_CORE define"
#endif
@ -49,6 +52,113 @@ extern "C" {
CPython refcounting operations on it!
*/
#if !defined(Py_GIL_DISABLED) && defined(Py_STACKREF_DEBUG)
typedef union _PyStackRef {
uint64_t index;
} _PyStackRef;
#define Py_TAG_BITS 0
PyAPI_FUNC(PyObject *) _Py_stackref_get_object(_PyStackRef ref);
PyAPI_FUNC(PyObject *) _Py_stackref_close(_PyStackRef ref);
PyAPI_FUNC(_PyStackRef) _Py_stackref_create(PyObject *obj, const char *filename, int linenumber);
PyAPI_FUNC(void) _Py_stackref_record_borrow(_PyStackRef ref, const char *filename, int linenumber);
extern void _Py_stackref_associate(PyInterpreterState *interp, PyObject *obj, _PyStackRef ref);
static const _PyStackRef PyStackRef_NULL = { .index = 0 };
#define PyStackRef_None ((_PyStackRef){ .index = 1 } )
#define PyStackRef_False ((_PyStackRef){ .index = 2 })
#define PyStackRef_True ((_PyStackRef){ .index = 3 })
#define LAST_PREDEFINED_STACKREF_INDEX 3
static inline int
PyStackRef_IsNull(_PyStackRef ref)
{
return ref.index == 0;
}
static inline int
PyStackRef_IsTrue(_PyStackRef ref)
{
return _Py_stackref_get_object(ref) == Py_True;
}
static inline int
PyStackRef_IsFalse(_PyStackRef ref)
{
return _Py_stackref_get_object(ref) == Py_False;
}
static inline int
PyStackRef_IsNone(_PyStackRef ref)
{
return _Py_stackref_get_object(ref) == Py_None;
}
static inline PyObject *
_PyStackRef_AsPyObjectBorrow(_PyStackRef ref, const char *filename, int linenumber)
{
_Py_stackref_record_borrow(ref, filename, linenumber);
return _Py_stackref_get_object(ref);
}
#define PyStackRef_AsPyObjectBorrow(REF) _PyStackRef_AsPyObjectBorrow((REF), __FILE__, __LINE__)
static inline PyObject *
PyStackRef_AsPyObjectSteal(_PyStackRef ref)
{
return _Py_stackref_close(ref);
}
static inline _PyStackRef
_PyStackRef_FromPyObjectNew(PyObject *obj, const char *filename, int linenumber)
{
Py_INCREF(obj);
return _Py_stackref_create(obj, filename, linenumber);
}
#define PyStackRef_FromPyObjectNew(obj) _PyStackRef_FromPyObjectNew(_PyObject_CAST(obj), __FILE__, __LINE__)
static inline _PyStackRef
_PyStackRef_FromPyObjectSteal(PyObject *obj, const char *filename, int linenumber)
{
return _Py_stackref_create(obj, filename, linenumber);
}
#define PyStackRef_FromPyObjectSteal(obj) _PyStackRef_FromPyObjectSteal(_PyObject_CAST(obj), __FILE__, __LINE__)
static inline _PyStackRef
_PyStackRef_FromPyObjectImmortal(PyObject *obj, const char *filename, int linenumber)
{
assert(_Py_IsImmortal(obj));
return _Py_stackref_create(obj, filename, linenumber);
}
#define PyStackRef_FromPyObjectImmortal(obj) _PyStackRef_FromPyObjectImmortal(_PyObject_CAST(obj), __FILE__, __LINE__)
static inline void
PyStackRef_CLOSE(_PyStackRef ref)
{
PyObject *obj = _Py_stackref_close(ref);
Py_DECREF(obj);
}
static inline _PyStackRef
_PyStackRef_DUP(_PyStackRef ref, const char *filename, int linenumber)
{
PyObject *obj = _Py_stackref_get_object(ref);
Py_INCREF(obj);
return _Py_stackref_create(obj, filename, linenumber);
}
#define PyStackRef_DUP(REF) _PyStackRef_DUP(REF, __FILE__, __LINE__)
#define PyStackRef_CLOSE_SPECIALIZED(stackref, dealloc) PyStackRef_CLOSE(stackref)
#else
typedef union _PyStackRef {
uintptr_t bits;
} _PyStackRef;
@ -200,12 +310,15 @@ static const _PyStackRef PyStackRef_NULL = { .bits = 0 };
#define PyStackRef_IsTrue(ref) (PyStackRef_AsPyObjectBorrow(ref) == Py_True)
#define PyStackRef_IsFalse(ref) (PyStackRef_AsPyObjectBorrow(ref) == Py_False)
#endif
// Converts a PyStackRef back to a PyObject *, converting the
// stackref to a new reference.
#define PyStackRef_AsPyObjectNew(stackref) Py_NewRef(PyStackRef_AsPyObjectBorrow(stackref))
#define PyStackRef_TYPE(stackref) Py_TYPE(PyStackRef_AsPyObjectBorrow(stackref))
#define PyStackRef_CLEAR(op) \
do { \
_PyStackRef *_tmp_op_ptr = &(op); \

1
Makefile.pre.in
View File

@ -488,6 +488,7 @@ PYTHON_OBJS= \
Python/qsbr.o \
Python/bootstrap_hash.o \
Python/specialize.o \
Python/stackrefs.o \
Python/structmember.o \
Python/symtable.o \
Python/sysmodule.o \

4
Misc/NEWS.d/next/Core_and_Builtins/2024-12-20-12-25-16.gh-issue-127705.WmCz1z.rst Normal file
View File

@ -0,0 +1,4 @@
Adds stackref debugging when ``Py_STACKREF_DEBUG`` is set. Finds all
double-closes and leaks, logging the origin and last borrow.
Inspired by HPy's debug mode. https://docs.hpyproject.org/en/latest/debug-mode.html

4
Objects/frameobject.c
View File

@ -179,9 +179,9 @@ framelocalsproxy_setitem(PyObject *self, PyObject *key, PyObject *value)
if (kind == CO_FAST_FREE) {
// The cell was set when the frame was created from
// the function's closure.
assert(oldvalue.bits != 0 && PyCell_Check(PyStackRef_AsPyObjectBorrow(oldvalue)));
assert(!PyStackRef_IsNull(oldvalue) && PyCell_Check(PyStackRef_AsPyObjectBorrow(oldvalue)));
cell = PyStackRef_AsPyObjectBorrow(oldvalue);
} else if (kind & CO_FAST_CELL && oldvalue.bits != 0) {
} else if (kind & CO_FAST_CELL && !PyStackRef_IsNull(oldvalue)) {
PyObject *as_obj = PyStackRef_AsPyObjectBorrow(oldvalue);
if (PyCell_Check(as_obj)) {
cell = as_obj;

17
Python/bytecodes.c
View File

@ -681,7 +681,7 @@ dummy_func(
assert(Py_REFCNT(left_o) >= 2);
PyStackRef_CLOSE(left);
DEAD(left);
PyObject *temp = PyStackRef_AsPyObjectBorrow(*target_local);
PyObject *temp = PyStackRef_AsPyObjectSteal(*target_local);
PyUnicode_Append(&temp, right_o);
*target_local = PyStackRef_FromPyObjectSteal(temp);
PyStackRef_CLOSE_SPECIALIZED(right, _PyUnicode_ExactDealloc);
@ -4509,17 +4509,17 @@ dummy_func(
op(_DO_CALL_FUNCTION_EX, (func_st, unused, callargs_st, kwargs_st if (oparg & 1) -- result)) {
PyObject *func = PyStackRef_AsPyObjectBorrow(func_st);
PyObject *callargs = PyStackRef_AsPyObjectBorrow(callargs_st);
PyObject *kwargs = PyStackRef_AsPyObjectBorrow(kwargs_st);
// DICT_MERGE is called before this opcode if there are kwargs.
// It converts all dict subtypes in kwargs into regular dicts.
assert(kwargs == NULL || PyDict_CheckExact(kwargs));
assert(PyTuple_CheckExact(callargs));
EVAL_CALL_STAT_INC_IF_FUNCTION(EVAL_CALL_FUNCTION_EX, func);
PyObject *result_o;
assert(!_PyErr_Occurred(tstate));
if (opcode == INSTRUMENTED_CALL_FUNCTION_EX) {
PyObject *callargs = PyStackRef_AsPyObjectBorrow(callargs_st);
PyObject *kwargs = PyStackRef_AsPyObjectBorrow(kwargs_st);
assert(kwargs == NULL || PyDict_CheckExact(kwargs));
assert(PyTuple_CheckExact(callargs));
PyObject *arg = PyTuple_GET_SIZE(callargs) > 0 ?
PyTuple_GET_ITEM(callargs, 0) : &_PyInstrumentation_MISSING;
int err = _Py_call_instrumentation_2args(
@ -4550,7 +4550,10 @@ dummy_func(
if (Py_TYPE(func) == &PyFunction_Type &&
tstate->interp->eval_frame == NULL &&
((PyFunctionObject *)func)->vectorcall == _PyFunction_Vectorcall) {
PyObject *callargs = PyStackRef_AsPyObjectSteal(callargs_st);
assert(PyTuple_CheckExact(callargs));
PyObject *kwargs = PyStackRef_IsNull(kwargs_st) ? NULL : PyStackRef_AsPyObjectSteal(kwargs_st);
assert(kwargs == NULL || PyDict_CheckExact(kwargs));
Py_ssize_t nargs = PyTuple_GET_SIZE(callargs);
int code_flags = ((PyCodeObject *)PyFunction_GET_CODE(func))->co_flags;
PyObject *locals = code_flags & CO_OPTIMIZED ? NULL : Py_NewRef(PyFunction_GET_GLOBALS(func));
@ -4568,6 +4571,10 @@ dummy_func(
frame->return_offset = 1;
DISPATCH_INLINED(new_frame);
}
PyObject *callargs = PyStackRef_AsPyObjectBorrow(callargs_st);
assert(PyTuple_CheckExact(callargs));
PyObject *kwargs = PyStackRef_AsPyObjectBorrow(kwargs_st);
assert(kwargs == NULL || PyDict_CheckExact(kwargs));
result_o = PyObject_Call(func, callargs, kwargs);
}
PyStackRef_XCLOSE(kwargs_st);

67
Python/ceval.c
View File

@ -164,7 +164,7 @@ dump_stack(_PyInterpreterFrame *frame, _PyStackRef *stack_pointer)
PyErr_Clear();
}
// Don't call __repr__(), it might recurse into the interpreter.
printf("<%s at %p>", Py_TYPE(obj)->tp_name, (void *)(ptr->bits));
printf("<%s at %p>", Py_TYPE(obj)->tp_name, PyStackRef_AsPyObjectBorrow(*ptr));
}
printf("]\n");
fflush(stdout);
@ -805,7 +805,7 @@ _PyEval_EvalFrameDefault(PyThreadState *tstate, _PyInterpreterFrame *frame, int
#ifdef Py_DEBUG
#if defined(Py_DEBUG) && !defined(Py_STACKREF_DEBUG)
/* Set these to invalid but identifiable values for debugging. */
entry_frame.f_funcobj = (_PyStackRef){.bits = 0xaaa0};
entry_frame.f_locals = (PyObject*)0xaaa1;
@ -1810,27 +1810,48 @@ _PyEvalFramePushAndInit_Ex(PyThreadState *tstate, _PyStackRef func,
{
bool has_dict = (kwargs != NULL && PyDict_GET_SIZE(kwargs) > 0);
PyObject *kwnames = NULL;
PyObject *const *newargs;
_PyStackRef *newargs;
PyObject *const *object_array = NULL;
_PyStackRef stack_array[8];
if (has_dict) {
newargs = _PyStack_UnpackDict(tstate, _PyTuple_ITEMS(callargs), nargs, kwargs, &kwnames);
object_array = _PyStack_UnpackDict(tstate, _PyTuple_ITEMS(callargs), nargs, kwargs, &kwnames);
if (object_array == NULL) {
PyStackRef_CLOSE(func);
goto error;
}
size_t total_args = nargs + PyDict_GET_SIZE(kwargs);
assert(sizeof(PyObject *) == sizeof(_PyStackRef));
newargs = (_PyStackRef *)object_array;
for (size_t i = 0; i < total_args; i++) {
newargs[i] = PyStackRef_FromPyObjectSteal(object_array[i]);
}
}
else {
if (nargs <= 8) {
newargs = stack_array;
}
else {
newargs = PyMem_Malloc(sizeof(_PyStackRef) *nargs);
if (newargs == NULL) {
PyErr_NoMemory();
PyStackRef_CLOSE(func);
goto error;
}
}
else {
newargs = &PyTuple_GET_ITEM(callargs, 0);
/* We need to incref all our args since the new frame steals the references. */
for (Py_ssize_t i = 0; i < nargs; ++i) {
Py_INCREF(PyTuple_GET_ITEM(callargs, i));
/* We need to create a new reference for all our args since the new frame steals them. */
for (Py_ssize_t i = 0; i < nargs; i++) {
newargs[i] = PyStackRef_FromPyObjectNew(PyTuple_GET_ITEM(callargs, i));
}
}
_PyInterpreterFrame *new_frame = _PyEvalFramePushAndInit(
tstate, func, locals,
(_PyStackRef const *)newargs, nargs, kwnames, previous
newargs, nargs, kwnames, previous
);
if (has_dict) {
_PyStack_UnpackDict_FreeNoDecRef(newargs, kwnames);
_PyStack_UnpackDict_FreeNoDecRef(object_array, kwnames);
}
else if (nargs > 8) {
PyMem_Free((void *)newargs);
}
/* No need to decref func here because the reference has been stolen by
_PyEvalFramePushAndInit.
@ -1850,21 +1871,39 @@ _PyEval_Vector(PyThreadState *tstate, PyFunctionObject *func,
PyObject* const* args, size_t argcount,
PyObject *kwnames)
{
size_t total_args = argcount;
if (kwnames) {
total_args += PyTuple_GET_SIZE(kwnames);
}
_PyStackRef stack_array[8];
_PyStackRef *arguments;
if (total_args <= 8) {
arguments = stack_array;
}
else {
arguments = PyMem_Malloc(sizeof(_PyStackRef) * total_args);
if (arguments == NULL) {
return PyErr_NoMemory();
}
}
/* _PyEvalFramePushAndInit consumes the references
* to func, locals and all its arguments */
Py_XINCREF(locals);
for (size_t i = 0; i < argcount; i++) {
Py_INCREF(args[i]);
arguments[i] = PyStackRef_FromPyObjectNew(args[i]);
}
if (kwnames) {
Py_ssize_t kwcount = PyTuple_GET_SIZE(kwnames);
for (Py_ssize_t i = 0; i < kwcount; i++) {
Py_INCREF(args[i+argcount]);
arguments[i+argcount] = PyStackRef_FromPyObjectNew(args[i+argcount]);
}
}
_PyInterpreterFrame *frame = _PyEvalFramePushAndInit(
tstate, PyStackRef_FromPyObjectNew(func), locals,
(_PyStackRef const *)args, argcount, kwnames, NULL);
arguments, argcount, kwnames, NULL);
if (total_args > 8) {
PyMem_Free(arguments);
}
if (frame == NULL) {
return NULL;
}

6
Python/ceval_macros.h
View File

@ -450,7 +450,7 @@ do { \
/* How much scratch space to give stackref to PyObject* conversion. */
#define MAX_STACKREF_SCRATCH 10
#ifdef Py_GIL_DISABLED
#if defined(Py_GIL_DISABLED) || defined(Py_STACKREF_DEBUG)
#define STACKREFS_TO_PYOBJECTS(ARGS, ARG_COUNT, NAME) \
/* +1 because vectorcall might use -1 to write self */ \
PyObject *NAME##_temp[MAX_STACKREF_SCRATCH+1]; \
@ -461,7 +461,7 @@ do { \
assert(NAME != NULL);
#endif
#ifdef Py_GIL_DISABLED
#if defined(Py_GIL_DISABLED) || defined(Py_STACKREF_DEBUG)
#define STACKREFS_TO_PYOBJECTS_CLEANUP(NAME) \
/* +1 because we +1 previously */ \
_PyObjectArray_Free(NAME - 1, NAME##_temp);
@ -470,7 +470,7 @@ do { \
(void)(NAME);
#endif
#ifdef Py_GIL_DISABLED
#if defined(Py_GIL_DISABLED) || defined(Py_STACKREF_DEBUG)
#define CONVERSION_FAILED(NAME) ((NAME) == NULL)
#else
#define CONVERSION_FAILED(NAME) (0)

2
Python/executor_cases.c.h generated
View File

@ -850,7 +850,7 @@
*/
assert(Py_REFCNT(left_o) >= 2);
PyStackRef_CLOSE(left);
PyObject *temp = PyStackRef_AsPyObjectBorrow(*target_local);
PyObject *temp = PyStackRef_AsPyObjectSteal(*target_local);
PyUnicode_Append(&temp, right_o);
*target_local = PyStackRef_FromPyObjectSteal(temp);
PyStackRef_CLOSE_SPECIALIZED(right, _PyUnicode_ExactDealloc);

23
Python/generated_cases.c.h generated
View File

@ -208,7 +208,7 @@
*/
assert(Py_REFCNT(left_o) >= 2);
PyStackRef_CLOSE(left);
PyObject *temp = PyStackRef_AsPyObjectBorrow(*target_local);
PyObject *temp = PyStackRef_AsPyObjectSteal(*target_local);
PyUnicode_Append(&temp, right_o);
*target_local = PyStackRef_FromPyObjectSteal(temp);
PyStackRef_CLOSE_SPECIALIZED(right, _PyUnicode_ExactDealloc);
@ -1675,16 +1675,16 @@
callargs_st = tuple;
func_st = func;
PyObject *func = PyStackRef_AsPyObjectBorrow(func_st);
PyObject *callargs = PyStackRef_AsPyObjectBorrow(callargs_st);
PyObject *kwargs = PyStackRef_AsPyObjectBorrow(kwargs_st);
// DICT_MERGE is called before this opcode if there are kwargs.
// It converts all dict subtypes in kwargs into regular dicts.
assert(kwargs == NULL || PyDict_CheckExact(kwargs));
assert(PyTuple_CheckExact(callargs));
EVAL_CALL_STAT_INC_IF_FUNCTION(EVAL_CALL_FUNCTION_EX, func);
PyObject *result_o;
assert(!_PyErr_Occurred(tstate));
if (opcode == INSTRUMENTED_CALL_FUNCTION_EX) {
PyObject *callargs = PyStackRef_AsPyObjectBorrow(callargs_st);
PyObject *kwargs = PyStackRef_AsPyObjectBorrow(kwargs_st);
assert(kwargs == NULL || PyDict_CheckExact(kwargs));
assert(PyTuple_CheckExact(callargs));
PyObject *arg = PyTuple_GET_SIZE(callargs) > 0 ?
PyTuple_GET_ITEM(callargs, 0) : &_PyInstrumentation_MISSING;
stack_pointer[-1 - (oparg & 1)] = callargs_st;
@ -1724,19 +1724,22 @@
if (Py_TYPE(func) == &PyFunction_Type &&
tstate->interp->eval_frame == NULL &&
((PyFunctionObject *)func)->vectorcall == _PyFunction_Vectorcall) {
PyObject *callargs = PyStackRef_AsPyObjectSteal(callargs_st);
assert(PyTuple_CheckExact(callargs));
PyObject *kwargs = PyStackRef_IsNull(kwargs_st) ? NULL : PyStackRef_AsPyObjectSteal(kwargs_st);
assert(kwargs == NULL || PyDict_CheckExact(kwargs));
Py_ssize_t nargs = PyTuple_GET_SIZE(callargs);
int code_flags = ((PyCodeObject *)PyFunction_GET_CODE(func))->co_flags;
PyObject *locals = code_flags & CO_OPTIMIZED ? NULL : Py_NewRef(PyFunction_GET_GLOBALS(func));
stack_pointer[-1 - (oparg & 1)] = callargs_st;
if (oparg & 1) stack_pointer[-(oparg & 1)] = kwargs_st;
stack_pointer += -2 - (oparg & 1);
assert(WITHIN_STACK_BOUNDS());
_PyFrame_SetStackPointer(frame, stack_pointer);
_PyInterpreterFrame *new_frame = _PyEvalFramePushAndInit_Ex(
tstate, func_st, locals,
nargs, callargs, kwargs, frame);
stack_pointer = _PyFrame_GetStackPointer(frame);
// Need to sync the stack since we exit with DISPATCH_INLINED.
stack_pointer += -3 - (oparg & 1);
stack_pointer += -1;
assert(WITHIN_STACK_BOUNDS());
if (new_frame == NULL) {
goto error;
@ -1745,6 +1748,10 @@
frame->return_offset = 1;
DISPATCH_INLINED(new_frame);
}
PyObject *callargs = PyStackRef_AsPyObjectBorrow(callargs_st);
assert(PyTuple_CheckExact(callargs));
PyObject *kwargs = PyStackRef_AsPyObjectBorrow(kwargs_st);
assert(kwargs == NULL || PyDict_CheckExact(kwargs));
stack_pointer[-1 - (oparg & 1)] = callargs_st;
if (oparg & 1) stack_pointer[-(oparg & 1)] = kwargs_st;
_PyFrame_SetStackPointer(frame, stack_pointer);

29
Python/pystate.c
View File

@ -19,6 +19,7 @@
#include "pycore_pymem.h" // _PyMem_SetDefaultAllocator()
#include "pycore_pystate.h"
#include "pycore_runtime_init.h" // _PyRuntimeState_INIT
#include "pycore_stackref.h" // Py_STACKREF_DEBUG
#include "pycore_obmalloc.h" // _PyMem_obmalloc_state_on_heap()
#include "pycore_uniqueid.h" // _PyObject_FinalizePerThreadRefcounts()
@ -663,6 +664,23 @@ init_interpreter(PyInterpreterState *interp,
/* Fix the self-referential, statically initialized fields. */
interp->dtoa = (struct _dtoa_state)_dtoa_state_INIT(interp);
}
#if !defined(Py_GIL_DISABLED) && defined(Py_STACKREF_DEBUG)
interp->next_stackref = 1;
_Py_hashtable_allocator_t alloc = {
.malloc = malloc,
.free = free,
};
interp->stackref_debug_table = _Py_hashtable_new_full(
_Py_hashtable_hash_ptr,
_Py_hashtable_compare_direct,
NULL,
NULL,
&alloc
);
_Py_stackref_associate(interp, Py_None, PyStackRef_None);
_Py_stackref_associate(interp, Py_False, PyStackRef_False);
_Py_stackref_associate(interp, Py_True, PyStackRef_True);
#endif
interp->_initialized = 1;
return _PyStatus_OK();
@ -768,6 +786,11 @@ PyInterpreterState_New(void)
return interp;
}
#if !defined(Py_GIL_DISABLED) && defined(Py_STACKREF_DEBUG)
extern void
_Py_stackref_report_leaks(PyInterpreterState *interp);
#endif
static void
interpreter_clear(PyInterpreterState *interp, PyThreadState *tstate)
{
@ -877,6 +900,12 @@ interpreter_clear(PyInterpreterState *interp, PyThreadState *tstate)
Py_CLEAR(interp->sysdict);
Py_CLEAR(interp->builtins);
#if !defined(Py_GIL_DISABLED) && defined(Py_STACKREF_DEBUG)
_Py_stackref_report_leaks(interp);
_Py_hashtable_destroy(interp->stackref_debug_table);
interp->stackref_debug_table = NULL;
#endif
if (tstate->interp == interp) {
/* We are now safe to fix tstate->_status.cleared. */
// XXX Do this (much) earlier?

156
Python/stackrefs.c Normal file
View File

@ -0,0 +1,156 @@
#include "Python.h"
#include "pycore_stackref.h"
#if !defined(Py_GIL_DISABLED) && defined(Py_STACKREF_DEBUG)
#if SIZEOF_VOID_P < 8
#error "Py_STACKREF_DEBUG requires 64 bit machine"
#endif
#include "pycore_interp.h"
#include "pycore_hashtable.h"
typedef struct _table_entry {
PyObject *obj;
const char *classname;
const char *filename;
int linenumber;
const char *filename_borrow;
int linenumber_borrow;
} TableEntry;
TableEntry *
make_table_entry(PyObject *obj, const char *filename, int linenumber)
{
TableEntry *result = malloc(sizeof(TableEntry));
if (result == NULL) {
return NULL;
}
result->obj = obj;
result->classname = Py_TYPE(obj)->tp_name;
result->filename = filename;
result->linenumber = linenumber;
result->filename_borrow = NULL;
return result;
}
PyObject *
_Py_stackref_get_object(_PyStackRef ref)
{
if (ref.index == 0) {
return NULL;
}
PyInterpreterState *interp = PyInterpreterState_Get();
assert(interp != NULL);
if (ref.index >= interp->next_stackref) {
_Py_FatalErrorFormat(__func__, "Garbled stack ref with ID %" PRIu64 "\n", ref.index);
}
TableEntry *entry = _Py_hashtable_get(interp->stackref_debug_table, (void *)ref.index);
if (entry == NULL) {
_Py_FatalErrorFormat(__func__, "Accessing closed stack ref with ID %" PRIu64 "\n", ref.index);
}
return entry->obj;
}
PyObject *
_Py_stackref_close(_PyStackRef ref)
{
PyInterpreterState *interp = PyInterpreterState_Get();
if (ref.index >= interp->next_stackref) {
_Py_FatalErrorFormat(__func__, "Garbled stack ref with ID %" PRIu64 "\n", ref.index);
}
PyObject *obj;
if (ref.index <= LAST_PREDEFINED_STACKREF_INDEX) {
// Pre-allocated reference to None, False or True -- Do not clear
TableEntry *entry = _Py_hashtable_get(interp->stackref_debug_table, (void *)ref.index);
obj = entry->obj;
}
else {
TableEntry *entry = _Py_hashtable_steal(interp->stackref_debug_table, (void *)ref.index);
if (entry == NULL) {
_Py_FatalErrorFormat(__func__, "Invalid StackRef with ID %" PRIu64 "\n", (void *)ref.index);
}
obj = entry->obj;
free(entry);
}
return obj;
}
_PyStackRef
_Py_stackref_create(PyObject *obj, const char *filename, int linenumber)
{
if (obj == NULL) {
Py_FatalError("Cannot create a stackref for NULL");
}
PyInterpreterState *interp = PyInterpreterState_Get();
uint64_t new_id = interp->next_stackref++;
TableEntry *entry = make_table_entry(obj, filename, linenumber);
if (entry == NULL) {
Py_FatalError("No memory left for stackref debug table");
}
if (_Py_hashtable_set(interp->stackref_debug_table, (void *)new_id, entry) < 0) {
Py_FatalError("No memory left for stackref debug table");
}
return (_PyStackRef){ .index = new_id };
}
void
_Py_stackref_record_borrow(_PyStackRef ref, const char *filename, int linenumber)
{
if (ref.index <= LAST_PREDEFINED_STACKREF_INDEX) {
return;
}
PyInterpreterState *interp = PyInterpreterState_Get();
TableEntry *entry = _Py_hashtable_get(interp->stackref_debug_table, (void *)ref.index);
if (entry == NULL) {
_Py_FatalErrorFormat(__func__, "Invalid StackRef with ID %" PRIu64 "\n", (void *)ref.index);
}
entry->filename_borrow = filename;
entry->linenumber_borrow = linenumber;
}
void
_Py_stackref_associate(PyInterpreterState *interp, PyObject *obj, _PyStackRef ref)
{
assert(interp->next_stackref >= ref.index);
interp->next_stackref = ref.index+1;
TableEntry *entry = make_table_entry(obj, "builtin-object", 0);
if (entry == NULL) {
Py_FatalError("No memory left for stackref debug table");
}
if (_Py_hashtable_set(interp->stackref_debug_table, (void *)ref.index, (void *)entry) < 0) {
Py_FatalError("No memory left for stackref debug table");
}
}
static int
report_leak(_Py_hashtable_t *ht, const void *key, const void *value, void *leak)
{
TableEntry *entry = (TableEntry *)value;
if (!_Py_IsStaticImmortal(entry->obj)) {
*(int *)leak = 1;
printf("Stackref leak. Refers to instance of %s at %p. Created at %s:%d",
entry->classname, entry->obj, entry->filename, entry->linenumber);
if (entry->filename_borrow != NULL) {
printf(". Last borrow at %s:%d",entry->filename_borrow, entry->linenumber_borrow);
}
printf("\n");
}
return 0;
}
void
_Py_stackref_report_leaks(PyInterpreterState *interp)
{
int leak = 0;
_Py_hashtable_foreach(interp->stackref_debug_table, report_leak, &leak);
if (leak) {
Py_FatalError("Stackrefs leaked.");
}
}
#endif