Files

93 lines
3.5 KiB
Python

import torch
__all__ = [
"GreenContext",
]
_GreenContext = object
SUPPORTED = False
if hasattr(torch._C, "_CUDAGreenContext"):
_GreenContext = torch._C._CUDAGreenContext # type: ignore[misc]
SUPPORTED = True
# Python shim helps Sphinx process docstrings more reliably.
# pyrefly: ignore [invalid-inheritance]
class GreenContext(_GreenContext):
r"""Wrapper around a CUDA green context.
.. warning::
This API is in beta and may change in future releases.
"""
@staticmethod
def create(
*,
num_sms: int | None = None,
workqueue_scope: str | None = None,
workqueue_concurrency_limit: int | None = None,
device_id: int | None = None,
) -> _GreenContext:
r"""Create a CUDA green context.
At least one of ``num_sms`` or ``workqueue_scope`` must be specified.
Both can be combined to partition SMs and configure workqueues in the
same green context.
Arguments:
num_sms (int, optional): The number of SMs to use in the green
context. When ``None``, SMs are not partitioned.
workqueue_scope (str, optional): Workqueue sharing scope. One of
``"device_ctx"`` (shared across all contexts, default driver
behaviour) or ``"balanced"`` (non-overlapping workqueues with
other balanced green contexts). When ``None``, no workqueue
configuration is applied.
workqueue_concurrency_limit (int, optional): Maximum number of
concurrent stream-ordered workloads for the workqueue. Requires
``workqueue_scope`` to be set.
device_id (int, optional): The device index of green context.
When ``None``, the current device is used.
"""
if not SUPPORTED:
raise RuntimeError("PyTorch was not built with Green Context support!")
return _GreenContext.create( # type: ignore[attr-defined]
device_id=device_id,
num_sms=num_sms,
workqueue_scope=workqueue_scope,
workqueue_concurrency_limit=workqueue_concurrency_limit,
)
@staticmethod
def max_workqueue_concurrency(device_id: int | None = None) -> int:
r"""Return the maximum workqueue concurrency limit for the device.
This queries the device for the default number of concurrent
stream-ordered workloads supported by workqueue configuration
resources.
Arguments:
device_id (int, optional): The device index to query. When
``None``, the current device is used.
"""
if not SUPPORTED:
raise RuntimeError("PyTorch was not built with Green Context support!")
return _GreenContext.max_workqueue_concurrency(device_id=device_id) # type: ignore[attr-defined]
# Note that these functions are bypassed but we define them here
# for Sphinx documentation purposes
def set_context(self) -> None: # pylint: disable=useless-parent-delegation
r"""Make the green context the current context."""
return super().set_context() # type: ignore[misc]
def pop_context(self) -> None: # pylint: disable=useless-parent-delegation
r"""Assuming the green context is the current context, pop it from the
context stack and restore the previous context.
"""
return super().pop_context() # type: ignore[misc]
def Stream(self) -> "torch.cuda.Stream":
r"""Return the CUDA Stream used by the green context."""
return super().Stream()