rocm_jax/jax/_src/dlpack.py
Skye Wanderman-Milne ecee8f9116 [JAX] Implement importing external dlpack-aware Python arrays.
See https://dmlc.github.io/dlpack/latest/python_spec.html.

This is the import path. The export path was implemented in
0b3cbfe4bc.

This allows for creating jax.Arrays from external GPU arrays
asynchronously.

PiperOrigin-RevId: 561172624
2023-08-29 16:39:31 -07:00

133 lines
4.6 KiB
Python

# Copyright 2020 The JAX Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
import enum
from jax import numpy as jnp
from jax._src import array
from jax._src import xla_bridge
from jax._src.lib import xla_client
from jax._src.lib import xla_extension_version
from jax._src.typing import Array
SUPPORTED_DTYPES = frozenset({
jnp.int8, jnp.int16, jnp.int32, jnp.int64, jnp.uint8, jnp.uint16,
jnp.uint32, jnp.uint64, jnp.float16, jnp.bfloat16, jnp.float32,
jnp.float64, jnp.complex64, jnp.complex128})
# Mirror of dlpack.h enum
class DLDeviceType(enum.IntEnum):
kDLCPU = 1
kDLCUDA = 2
kDLROCM = 10
def to_dlpack(x: Array, take_ownership: bool = False,
stream: int | None = None):
"""Returns a DLPack tensor that encapsulates a :class:`~jax.Array` ``x``.
Takes ownership of the contents of ``x``; leaves ``x`` in an invalid/deleted
state.
Args:
x: a :class:`~jax.Array`, on either CPU or GPU.
take_ownership: If ``True``, JAX hands ownership of the buffer to DLPack,
and the consumer is free to mutate the buffer; the JAX buffer acts as if
it were deleted. If ``False``, JAX retains ownership of the buffer; it is
undefined behavior if the DLPack consumer writes to a buffer that JAX
owns.
stream: optional platform-dependent stream to wait on until the buffer is
ready. This corresponds to the `stream` argument to ``__dlpack__``
documented in https://dmlc.github.io/dlpack/latest/python_spec.html.
"""
if not isinstance(x, array.ArrayImpl):
raise TypeError("Argument to to_dlpack must be a jax.Array, "
f"got {type(x)}")
assert len(x.devices()) == 1
if xla_extension_version >= 186:
return xla_client._xla.buffer_to_dlpack_managed_tensor(
x.addressable_data(0), take_ownership=take_ownership, stream=stream
) # type: ignore
else:
if stream is not None:
raise ValueError(
"passing `stream` argument to to_dlpack requires jaxlib >= 0.4.15")
return xla_client._xla.buffer_to_dlpack_managed_tensor(
x.addressable_data(0), take_ownership=take_ownership) # type: ignore
def from_dlpack(external_array):
"""Returns a :class:`~jax.Array` representation of a DLPack tensor.
The returned :class:`~jax.Array` shares memory with ``external_array``.
Args:
external_array: an array object that has __dlpack__ and __dlpack_device__
methods, or a DLPack tensor on either CPU or GPU (legacy API).
Returns:
A jax.Array
"""
if hasattr(external_array, "__dlpack__") and xla_extension_version >= 191:
dl_device_type, device_id = external_array.__dlpack_device__()
try:
device_platform = {
DLDeviceType.kDLCPU: "cpu",
DLDeviceType.kDLCUDA: "cuda",
DLDeviceType.kDLROCM: "rocm",
}[dl_device_type]
except TypeError:
# https://dmlc.github.io/dlpack/latest/python_spec.html recommends using
# TypeError.
raise TypeError(
"Array passed to from_dlpack is on unsupported device type "
f"(DLDeviceType: {dl_device_type}, array: {external_array}")
backend = xla_bridge.get_backend(device_platform)
device = backend.device_from_local_hardware_id(device_id)
try:
stream = device.get_stream_for_external_ready_events()
except xla_client.XlaRuntimeError as err: # type: ignore
if "UNIMPLEMENTED" in str(err):
stream = None
else:
raise
dlpack = external_array.__dlpack__(stream)
return jnp.asarray(xla_client._xla.dlpack_managed_tensor_to_buffer(
dlpack, device, stream))
else:
# Legacy path
dlpack = external_array
cpu_backend = xla_bridge.get_backend("cpu")
try:
gpu_backend = xla_bridge.get_backend("cuda")
except RuntimeError:
gpu_backend = None
# Try ROCm if CUDA backend not found
if gpu_backend is None:
try:
gpu_backend = xla_bridge.get_backend("rocm")
except RuntimeError:
gpu_backend = None
return jnp.asarray(xla_client._xla.dlpack_managed_tensor_to_buffer(
dlpack, cpu_backend, gpu_backend))