blob: c11828db9dc14be18c8f7417b4dc21a55431a8ee [file] [log] [blame]
#include <torch/csrc/autograd/python_variable.h>
#include <torch/csrc/THP.h>
#include <torch/csrc/DynamicTypes.h>
#include <torch/csrc/Exceptions.h>
#include <torch/csrc/Device.h>
#include <torch/csrc/Size.h>
#include <torch/csrc/Types.h>
#include <torch/csrc/autograd/edge.h>
#include <torch/csrc/autograd/python_cpp_function.h>
#include <torch/csrc/autograd/python_hook.h>
#include <torch/csrc/autograd/python_variable_indexing.h>
#include <torch/csrc/autograd/variable.h>
#include <torch/csrc/autograd/functions/accumulate_grad.h>
#include <torch/csrc/autograd/function.h>
#include <torch/csrc/autograd/generated/VariableType.h>
#include <torch/csrc/autograd/utils/python_error_messages.h>
#include <torch/csrc/autograd/utils/wrap_outputs.h>
#include <torch/csrc/tensor/python_tensor.h>
#include <torch/csrc/utils/auto_gil.h>
#include <torch/csrc/utils/cuda_lazy_init.h>
#include <torch/csrc/utils/pybind.h>
#include <torch/csrc/utils/python_strings.h>
#include <torch/csrc/utils/python_arg_parser.h>
#include <torch/csrc/utils/tensor_new.h>
#include <torch/csrc/jit/tracer.h>
#ifdef BUILD_NAMEDTENSOR
#include <ATen/NamedTensorUtils.h>
#endif
#include <ATen/ATen.h>
#include <pybind11/pybind11.h>
#include <structmember.h>
#include <memory>
#include <utility>
#include <vector>
using namespace at;
using namespace torch;
using namespace torch::autograd;
namespace py = pybind11;
PyObject *THPVariableClass = nullptr;
static const char* VOLATILE_WARNING =
"volatile was removed and now has no effect. Use "
"`with torch.no_grad():` instead.";
// Creates a new Python object for a Variable. The Variable must not already
// have a PyObject* associated with it.
static PyObject* THPVariable_NewWithVar(PyTypeObject* type, Variable var)
{
PyObject* obj = type->tp_alloc(type, 0);
if (obj) {
auto v = (THPVariable*) obj;
new (&v->cdata) Variable(std::move(var));
v->cdata.set_pyobj(obj);
}
return obj;
}
PyObject * THPVariable_Wrap(Variable var)
{
if (!var.defined()) {
Py_RETURN_NONE;
}
if (auto obj = var.pyobj()) {
Py_INCREF(obj);
return obj;
}
return THPVariable_NewWithVar((PyTypeObject *)THPVariableClass, std::move(var));
}
static int THPVariable_traverse(THPVariable *self, visitproc visit, void *arg)
{
Py_VISIT(self->backward_hooks);
// We don't want to traverse the grad_fn, even if the Variable owns it and the
// shared pointer's use count is 1. This is because we would need to treat
// the grad_fn as part of the Python state and hold the GIL sometimes when
// grad_fn's shared_ptr is copied, otherwise a race condition with the Python
// GC could occur. Holding the GIL when the shared_ptr is copied adds
// undesirable complexity/overhead.
//
// When hooks, a Variable, and its grad_fn are involved in a Python reference
// cycle, because we're not traversing the grad_fn, the reference cycle will
// in fact leak.
//
// See https://gist.github.com/zou3519/7ac92b84dd7d206dcc6eae55fee8372c
// for more details about the race condition involving traversing the grad_fn
// and the python GC.
if (self->cdata.defined()) {
for (const auto& hook : self->cdata.hooks()) {
if (auto pyhook = dynamic_cast<PyFunctionPreHook*>(hook.get())) {
Py_VISIT(pyhook->dict);
}
}
}
return 0;
}
static int THPVariable_clear(THPVariable *self)
{
Py_CLEAR(self->backward_hooks);
if (self->cdata.defined()) {
if (auto grad_acc = self->cdata.try_get_grad_accumulator()) {
grad_acc->pre_hooks().clear();
}
// We must clear the pyobj field in the base C++ Variable, to ensure
// that if we attempt to pass the Variable to Python, we don't
// attempt to reuse the (now-dead) PyObject.
//
// One non-obvious consequence of this: if you have a tensor x, you
// take its id(), and then you let it become dead in Python, if you
// get another reference to the tensor in Python later (because you
// passed it from C++ to Python), you'll get a *different* id() the
// second time around. So you better make sure that if you're using
// id() to keep track of Tensors, you better make sure their Python
// objects stay live, buster! See
// https://github.com/pytorch/pytorch/issues/22884 for an example of
// this actually showing up.
self->cdata.set_pyobj(nullptr);
}
self->cdata.reset();
return 0;
}
static void THPVariable_dealloc(THPVariable* self)
{
PyObject_GC_UnTrack(self);
THPVariable_clear(self);
self->cdata.~Variable();
Py_TYPE(self)->tp_free((PyObject*)self);
}
static PyObject *THPVariable_pynew(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
HANDLE_TH_ERRORS
jit::tracer::warn("torch.Tensor", jit::tracer::WARN_CONSTRUCTOR);
auto tensor = torch::utils::legacy_tensor_ctor(torch::tensors::get_default_tensor_type_id(), torch::tensors::get_default_scalar_type(), args, kwargs);
return THPVariable_NewWithVar(type, std::move(tensor));
END_HANDLE_TH_ERRORS
}
// Instantiates a subclass of torch.Tensor. Used by nn.Parameter()
static PyObject* THPVariable_make_subclass(PyObject* _ignored, PyObject* args, PyObject* kwargs) {
HANDLE_TH_ERRORS
static PythonArgParser parser({
"_make_subclass(PyObject* cls, Tensor data, bool require_grad=False)",
});
ParsedArgs<3> parsed_args{};
auto r = parser.parse(args, kwargs, parsed_args);
PyObject* cls = r.pyobject(0);
if (!PyType_Check(cls)) {
throw TypeError("cls must be a type (got %s)", Py_TYPE(cls)->tp_name);
}
auto data = as_variable_ref(r.tensor(1)).detach();
// We set `data`'s `allow_tensor_metadata_change` to true here, because we want to
// allow the following use case for backward compatibility:
//
// ```python
// rnn = torch.nn.RNN(100, 100, 2)
// # The following calls `torch._cudnn_rnn_flatten_weight(rnn._flat_weights, ...)`,
// # which changes storage of `rnn`'s weights in-place
// rnn.flatten_parameters()
// ```
data.unsafeGetTensorImpl()->set_allow_tensor_metadata_change(true);
auto var = data.set_requires_grad(r.toBool(2));
return THPVariable_NewWithVar((PyTypeObject*)cls, std::move(var));
END_HANDLE_TH_ERRORS
}
typedef PyObject *(*getter)(PyObject *, void *);
typedef int (*setter)(PyObject *, PyObject *, void *);
PyObject *THPVariable_get_T(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& var = self->cdata;
return THPVariable_Wrap(var.numpy_T());
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_get_cdata(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& var = self->cdata;
return PyLong_FromVoidPtr(var.unsafeGetTensorImpl());
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_get_version(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& var = self->cdata;
return PyInt_FromLong(var.current_version());
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_get_grad_fn(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& var = self->cdata;
if (!var.grad_fn()) {
Py_RETURN_NONE;
}
return functionToPyObject(var.grad_fn());
END_HANDLE_TH_ERRORS
}
static int THPVariable_set_grad_fn(THPVariable *self, PyObject *obj)
{
HANDLE_TH_ERRORS
THPUtils_assertRet(-1, obj, "Deletion of _grad_fn not allowed. Detach tensor instead!");
THPUtils_assertRet(-1, obj == Py_None, "_grad_fn can be only set to None");
self->cdata.detach_();
return 0;
END_HANDLE_TH_ERRORS_RET(-1)
}
static PyObject *THPVariable_is_leaf(THPVariable *self)
{
HANDLE_TH_ERRORS
return PyBool_FromLong(!self->cdata.grad_fn());
END_HANDLE_TH_ERRORS
}
static PyObject * THPVariable_get_data(THPVariable *self)
{
HANDLE_TH_ERRORS
auto var = self->cdata.variable_data();
return THPVariable_Wrap(var);
END_HANDLE_TH_ERRORS
}
int THPVariable_set_data(THPVariable *self, PyObject *data)
{
HANDLE_TH_ERRORS
THPUtils_assertRet(-1, data, "Deleting tensor data is not allowed. Delete tensor instead!");
if (!THPVariable_Check(data)) {
throw torch::TypeError("Variable data has to be a tensor, but got %s", Py_TYPE(data)->tp_name);
}
self->cdata.set_data(THPVariable_Unpack(data));
return 0;
END_HANDLE_TH_ERRORS_RET(-1)
}
PyObject *THPVariable_get_grad(THPVariable *self)
{
HANDLE_TH_ERRORS
return THPVariable_Wrap(self->cdata.grad());
END_HANDLE_TH_ERRORS
}
int THPVariable_set_grad(THPVariable *self, PyObject *py_grad)
{
HANDLE_TH_ERRORS
auto& var = self->cdata;
if (!py_grad || py_grad == Py_None) {
var.grad().reset();
return 0;
}
THPUtils_assertRet(-1, THPVariable_Check(py_grad),
"expected Variable or None (got %s)", THPUtils_typename(py_grad));
THPUtils_assertRet(-1, self != (THPVariable*)py_grad,
"can't assign Variable as its own grad");
auto& grad = ((THPVariable*)py_grad)->cdata;
bool gradIsSparse = var.dtype() == grad.dtype() && toSparse(tensorTypeIdToBackend(var.type_id())) == tensorTypeIdToBackend(grad.type_id());
THPUtils_assertRet(-1, grad.type() == var.type() || gradIsSparse,
"assigned grad has data of a different type");
if (var.is_cuda()) {
THPUtils_assertRet(-1, grad.get_device() == var.get_device(),
"assigned grad has data located on a different device");
}
THPUtils_assertRet(-1, grad.sizes().equals(var.sizes()),
"assigned grad has data of a different size");
var.grad() = grad;
return 0;
END_HANDLE_TH_ERRORS_RET(-1)
}
PyObject *THPVariable_get_volatile(THPVariable *self)
{
const char* msg = "volatile was removed (Variable.volatile is always False)";
PyErr_WarnEx(PyExc_UserWarning, msg, 1);
Py_RETURN_FALSE;
}
int THPVariable_set_volatile(THPVariable *self, PyObject *obj)
{
return PyErr_WarnEx(PyExc_UserWarning, VOLATILE_WARNING, 1);
}
PyObject *THPVariable_get_output_nr(THPVariable *self)
{
HANDLE_TH_ERRORS
const auto output_nr = static_cast<long>(self->cdata.output_nr());
return PyInt_FromLong(output_nr);
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_get_requires_grad(THPVariable *self)
{
HANDLE_TH_ERRORS
return PyBool_FromLong(self->cdata.requires_grad());
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_get_ndim(THPVariable *self)
{
HANDLE_TH_ERRORS
return PyInt_FromLong(self->cdata.dim());
END_HANDLE_TH_ERRORS
}
#ifdef BUILD_NAMEDTENSOR
PyObject *THPVariable_get_names(THPVariable *self)
{
HANDLE_TH_ERRORS
// The long-term plan is to return a list of (python) torch.Dimname.
// However, for now, return a list of string.
size_t size = self->cdata.dim();
THPObjectPtr tuple(PyTuple_New(size));
if (!tuple) throw python_error();
if (!self->cdata.is_named()) {
for (size_t i = 0; i < size; ++i) {
PyTuple_SET_ITEM(tuple.get(), i, Py_None);
}
return tuple.release();
}
const auto dimnames = self->cdata.names().value();
for (size_t i = 0; i < size; ++i) {
PyObject* str = Py_None;
if (dimnames[i].type() != at::NameType::WILDCARD) {
str = THPUtils_packString(dimnames[i].full_name().toUnqualString());
if (!str) throw python_error();
}
PyTuple_SET_ITEM(tuple.get(), i, str);
}
return tuple.release();
END_HANDLE_TH_ERRORS
}
int THPVariable_set_names(THPVariable *self, PyObject *names) {
HANDLE_TH_ERRORS
auto& var = self->cdata;
if (names == Py_None) {
at::internal_set_names_inplace(var, at::nullopt);
} else {
THPUtils_assertRet(-1,
THPUtils_checkDimnameList(names),
"names must either be None or a tuple of dim names");
at::internal_set_names_inplace(var, torch::parseDimnameList(names));
}
return 0;
END_HANDLE_TH_ERRORS_RET(-1)
}
#endif
int THPVariable_set_requires_grad(THPVariable *self, PyObject *obj)
{
HANDLE_TH_ERRORS
THPUtils_assertRet(-1, obj && PyBool_Check(obj), "requires_grad must be a bool");
auto& var = self->cdata;
auto requires_grad = (obj == Py_True);
if (!var.is_leaf()) {
THPUtils_setError(autograd::utils::requires_grad_leaf_error(obj == Py_True).c_str());
return -1;
}
if (requires_grad && !var.is_floating_point()) {
THPUtils_setError("only Tensors of floating point dtype can require gradients");
return -1;
}
var.set_requires_grad(requires_grad);
return 0;
END_HANDLE_TH_ERRORS_RET(-1)
}
PyObject *THPVariable_get_name(THPVariable* self)
{
if (self->cdata.name() == "")
Py_RETURN_NONE;
return THPUtils_packString(self->cdata.name().c_str());
}
PyObject *THPVariable_get_backwards_hooks(THPVariable *self)
{
HANDLE_TH_ERRORS
if (self->backward_hooks) {
Py_INCREF(self->backward_hooks);
return self->backward_hooks;
}
Py_RETURN_NONE;
END_HANDLE_TH_ERRORS
}
int THPVariable_set_backwards_hooks(THPVariable *self, PyObject *obj)
{
HANDLE_TH_ERRORS
THPUtils_assertRet(-1, obj, "Deletion of _backwards_hooks not allowed!");
if (obj == Py_None) {
obj = nullptr;
}
Py_XINCREF(obj);
Py_XDECREF(self->backward_hooks);
self->backward_hooks = obj;
self->cdata.clear_hooks();
if (obj) {
self->cdata.add_hook(std::make_shared<PyFunctionPreHook>(obj, 0));
}
return 0;
END_HANDLE_TH_ERRORS_RET(-1)
}
PyObject *THPVariable_get_base(THPVariable *self)
{
HANDLE_TH_ERRORS
if (self->cdata.is_view()) {
return THPVariable_Wrap(self->cdata.base());
}
Py_RETURN_NONE;
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_get_shape(THPVariable *self)
{
HANDLE_TH_ERRORS
return THPSize_New(self->cdata);
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_is_cuda(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& self_ = self->cdata;
return torch::autograd::utils::wrap(self_.is_cuda());
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_is_sparse(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& self_ = self->cdata;
return torch::autograd::utils::wrap(self_.is_sparse());
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_is_mkldnn(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& self_ = self->cdata;
return torch::autograd::utils::wrap(self_.is_mkldnn());
END_HANDLE_TH_ERRORS
}
PyObject *THPVariable_is_quantized(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& self_ = self->cdata;
return torch::autograd::utils::wrap(self_.is_quantized());
END_HANDLE_TH_ERRORS
}
static PyObject *THPVariable_dtype(THPVariable *self)
{
HANDLE_TH_ERRORS
auto& self_ = self->cdata;
return torch::autograd::utils::wrap(torch::getDtype(self_.scalar_type()));
END_HANDLE_TH_ERRORS
}
static PyObject * THPVariable_layout(THPVariable* self) {
HANDLE_TH_ERRORS
auto& self_ = self->cdata;
return torch::autograd::utils::wrap(torch::getLayout(self_.type().backend()));
END_HANDLE_TH_ERRORS
}
static PyObject * THPVariable_device(THPVariable* self) {
HANDLE_TH_ERRORS
return THPDevice_New(self->cdata.device());
END_HANDLE_TH_ERRORS
}
static struct PyGetSetDef THPVariable_properties[] = {
{"T", (getter)THPVariable_get_T, nullptr, nullptr, nullptr},
{"_cdata", (getter)THPVariable_get_cdata, nullptr, nullptr, nullptr},
{"_version", (getter)THPVariable_get_version, nullptr, nullptr, nullptr},
{"grad_fn", (getter)THPVariable_get_grad_fn, nullptr, nullptr, nullptr},
{"_grad_fn", (getter)THPVariable_get_grad_fn, (setter)THPVariable_set_grad_fn, nullptr, nullptr},
{"is_leaf", (getter)THPVariable_is_leaf, nullptr, nullptr, nullptr},
{"data", (getter)THPVariable_get_data, (setter)THPVariable_set_data, nullptr, nullptr},
{"_grad", (getter)THPVariable_get_grad, (setter)THPVariable_set_grad, nullptr, nullptr}, // only for legacy reasons
{"grad", (getter)THPVariable_get_grad, (setter)THPVariable_set_grad, nullptr, nullptr},
{"_base", (getter)THPVariable_get_base, nullptr, nullptr, nullptr},
{"volatile", (getter)THPVariable_get_volatile, (setter)THPVariable_set_volatile, nullptr, nullptr},
{"output_nr", (getter)THPVariable_get_output_nr, nullptr, nullptr, nullptr},
{"requires_grad", (getter)THPVariable_get_requires_grad, (setter)THPVariable_set_requires_grad, nullptr, nullptr},
{"_backward_hooks", (getter)THPVariable_get_backwards_hooks, (setter)THPVariable_set_backwards_hooks, nullptr, nullptr},
{"name", (getter)THPVariable_get_name, nullptr, nullptr, nullptr},
{"shape", (getter)THPVariable_get_shape, nullptr, nullptr, nullptr},
{"is_cuda", (getter)THPVariable_is_cuda, nullptr, nullptr, nullptr},
{"is_sparse", (getter)THPVariable_is_sparse, nullptr, nullptr, nullptr},
{"is_mkldnn", (getter)THPVariable_is_mkldnn, nullptr, nullptr, nullptr},
{"is_quantized", (getter)THPVariable_is_quantized, nullptr, nullptr, nullptr},
{"dtype", (getter)THPVariable_dtype, nullptr, nullptr, nullptr},
{"layout", (getter)THPVariable_layout, nullptr, nullptr, nullptr},
{"device", (getter)THPVariable_device, nullptr, nullptr, nullptr},
{"ndim", (getter)THPVariable_get_ndim, nullptr, nullptr, nullptr},
#ifdef BUILD_NAMEDTENSOR
{"names", (getter)THPVariable_get_names, (setter)THPVariable_set_names, nullptr, nullptr},
#endif
{nullptr}
};
static PyMappingMethods THPVariable_as_mapping = {
THPVariable_length,
THPVariable_getitem,
THPVariable_setitem,
};
static PyMethodDef extra_methods[] = {
{"_make_subclass", (PyCFunction)THPVariable_make_subclass, METH_STATIC | METH_VARARGS | METH_KEYWORDS, nullptr},
{nullptr}
};
PyTypeObject THPVariableType = {
PyVarObject_HEAD_INIT(nullptr, 0)
"torch._C._TensorBase", /* tp_name */
sizeof(THPVariable), /* tp_basicsize */
0, /* tp_itemsize */
(destructor)THPVariable_dealloc, /* tp_dealloc */
nullptr, /* tp_print */
nullptr, /* tp_getattr */
nullptr, /* tp_setattr */
nullptr, /* tp_reserved */
nullptr, /* tp_repr */
nullptr, /* tp_as_number */
nullptr, /* tp_as_sequence */
&THPVariable_as_mapping, /* tp_as_mapping */
nullptr, /* tp_hash */
nullptr, /* tp_call */
nullptr, /* tp_str */
nullptr, /* tp_getattro */
nullptr, /* tp_setattro */
nullptr, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /* tp_flags */
nullptr, /* tp_doc */
(traverseproc)THPVariable_traverse, /* tp_traverse */
(inquiry)THPVariable_clear, /* tp_clear */
nullptr, /* tp_richcompare */
0, /* tp_weaklistoffset */
nullptr, /* tp_iter */
nullptr, /* tp_iternext */
nullptr, /* tp_methods */
nullptr, /* tp_members */
THPVariable_properties, /* tp_getset */
nullptr, /* tp_base */
nullptr, /* tp_dict */
nullptr, /* tp_descr_get */
nullptr, /* tp_descr_set */
0, /* tp_dictoffset */
nullptr, /* tp_init */
nullptr, /* tp_alloc */
THPVariable_pynew /* tp_new */
};
namespace torch { namespace autograd {
extern PyMethodDef variable_methods[];
extern void initTorchFunctions(PyObject *module);
void initTensorImplConversion(PyObject* module) {
auto m = py::handle(module).cast<py::module>();
m.def("_wrap_tensor_impl", [](void* ptr) {
auto p = c10::intrusive_ptr<c10::TensorImpl, at::UndefinedTensorImpl>::
unsafe_reclaim_from_nonowning(static_cast<c10::TensorImpl*>(ptr));
TORCH_CHECK(p.defined(), "Can't wrap undefined tensor");
auto tensor = at::Tensor::wrap_tensor_impl(std::move(p));
// For now, there is no guarantee that the tensors returned from Caffe2 ops
// are not Variables, because inputs to Caffe2 ops can be Variables.
//
// In the near future, once we make every tensor a Variable, we can remove
// the `tensor.is_variable()` check and directly return `tensor` as a Variable.
return py::cast(tensor.is_variable() ? torch::autograd::Variable(tensor) :
torch::autograd::make_variable(std::move(tensor), false));
});
// set on the module level to avoid mixing pybind and plain CPython extensions
m.def("_tensor_impl_raw_handle", [](torch::autograd::Variable* t) -> void* {
// We return a raw non-owning pointer here, we rely on surrounding
// code to keep the original tensor alive
return t->getIntrusivePtr().get();
});
}
}}
bool THPVariable_initModule(PyObject *module)
{
static std::vector<PyMethodDef> methods;
THPUtils_addPyMethodDefs(methods, torch::autograd::variable_methods);
THPUtils_addPyMethodDefs(methods, extra_methods);
THPVariableType.tp_methods = methods.data();
if (PyType_Ready(&THPVariableType) < 0)
return false;
Py_INCREF(&THPVariableType);
PyModule_AddObject(module, "_TensorBase", (PyObject *)&THPVariableType);
torch::autograd::initTorchFunctions(module);
torch::autograd::initTensorImplConversion(module);
return true;
}