lightning/pytorch_lightning/utilities/xla_device.py

105 lines
2.9 KiB
Python

# Copyright The PyTorch Lightning team.
#
# 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
#
# http://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.
import functools
import queue as q
import traceback
from multiprocessing import Process, Queue
import torch
from pytorch_lightning.utilities.imports import _XLA_AVAILABLE
if _XLA_AVAILABLE:
import torch_xla.core.xla_model as xm
def inner_f(queue, func, *args, **kwargs): # pragma: no cover
try:
queue.put(func(*args, **kwargs))
# todo: specify the possible exception
except Exception:
traceback.print_exc()
queue.put(None)
def pl_multi_process(func):
@functools.wraps(func)
def wrapper(*args, **kwargs):
queue = Queue()
proc = Process(target=inner_f, args=(queue, func, *args), kwargs=kwargs)
proc.start()
proc.join(20)
try:
return queue.get_nowait()
except q.Empty:
traceback.print_exc()
return False
return wrapper
class XLADeviceUtils:
"""Used to detect the type of XLA device"""
TPU_AVAILABLE = None
@staticmethod
def _fetch_xla_device_type(device: torch.device) -> str:
"""
Returns XLA device type
Args:
device: (:class:`~torch.device`): Accepts a torch.device type with a XLA device format i.e xla:0
Return:
Returns a str of the device hardware type. i.e TPU
"""
if _XLA_AVAILABLE:
return xm.xla_device_hw(device)
@staticmethod
def _is_device_tpu() -> bool:
"""
Check if device is TPU
Return:
A boolean value indicating if the xla device is a TPU device or not
"""
if _XLA_AVAILABLE:
device = xm.xla_device()
device_type = XLADeviceUtils._fetch_xla_device_type(device)
return device_type == "TPU"
@staticmethod
def xla_available() -> bool:
"""
Check if XLA library is installed
Return:
A boolean value indicating if a XLA is installed
"""
return _XLA_AVAILABLE
@staticmethod
def tpu_device_exists() -> bool:
"""
Runs XLA device check within a separate process
Return:
A boolean value indicating if a TPU device exists on the system
"""
if XLADeviceUtils.TPU_AVAILABLE is None and _XLA_AVAILABLE:
XLADeviceUtils.TPU_AVAILABLE = pl_multi_process(XLADeviceUtils._is_device_tpu)()
return XLADeviceUtils.TPU_AVAILABLE