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Source code for torch.cuda

# mypy: allow-untyped-defs
r"""
This package adds support for CUDA tensor types.

It implements the same function as CPU tensors, but they utilize
GPUs for computation.

It is lazily initialized, so you can always import it, and use
:func:`is_available()` to determine if your system supports CUDA.

:ref:`cuda-semantics` has more details about working with CUDA.
"""

import importlib
import os
import threading
import traceback
import warnings
from functools import lru_cache
from typing import Any, Callable, cast, List, Optional, Tuple, Union

import torch
import torch._C
from torch import device as _device
from torch._utils import _dummy_type, _LazySeedTracker, classproperty
from torch.types import Device

from . import gds
from ._utils import _get_device_index
from .graphs import (
    CUDAGraph,
    graph,
    graph_pool_handle,
    is_current_stream_capturing,
    make_graphed_callables,
)
from .streams import Event, ExternalStream, Stream


try:
    from torch._C import _cudart  # type: ignore[attr-defined]
except ImportError:
    _cudart = None

_initialized = False
_tls = threading.local()
_initialization_lock = threading.Lock()
_queued_calls: List[
    Tuple[Callable[[], None], List[str]]
] = []  # don't invoke these until initialization occurs
_is_in_bad_fork = getattr(torch._C, "_cuda_isInBadFork", lambda: False)
_device_t = Union[_device, str, int, None]

_HAS_PYNVML = False
_PYNVML_ERR = None
try:
    from torch import version as _version

    try:
        if not _version.hip:
            import pynvml  # type: ignore[import]
        else:
            import amdsmi  # type: ignore[import]

        _HAS_PYNVML = True
    except ModuleNotFoundError:
        pass
    finally:
        del _version
except ImportError as err:
    _PYNVML_ERR = err  # sometimes a lib is installed but the import fails for some other reason, so we log the error for later

_lazy_seed_tracker = _LazySeedTracker()

# Define dummy _CudaDeviceProperties type if PyTorch was compiled without CUDA
if hasattr(torch._C, "_CudaDeviceProperties"):
    _CudaDeviceProperties = torch._C._CudaDeviceProperties
else:
    _CudaDeviceProperties = _dummy_type("_CudaDeviceProperties")  # type: ignore[assignment, misc]

if hasattr(torch._C, "_cuda_exchangeDevice"):
    _exchange_device = torch._C._cuda_exchangeDevice
else:

    def _exchange_device(device: int) -> int:
        if device < 0:
            return -1
        raise RuntimeError("PyTorch was compiled without CUDA support")


if hasattr(torch._C, "_cuda_maybeExchangeDevice"):
    _maybe_exchange_device = torch._C._cuda_maybeExchangeDevice
else:

    def _maybe_exchange_device(device: int) -> int:
        if device < 0:
            return -1
        raise RuntimeError("PyTorch was compiled without CUDA support")


has_half: bool = True
has_magma: bool = torch._C._has_magma

default_generators: Tuple[torch._C.Generator] = ()  # type: ignore[assignment]


def _is_compiled() -> bool:
    r"""Return true if compile with CUDA support."""
    return hasattr(torch._C, "_cuda_getDeviceCount")


def _nvml_based_avail() -> bool:
    return os.getenv("PYTORCH_NVML_BASED_CUDA_CHECK") == "1"


[docs]def is_available() -> bool: r"""Return a bool indicating if CUDA is currently available.""" if not _is_compiled(): return False if _nvml_based_avail(): # The user has set an env variable to request this availability check that attempts to avoid fork poisoning by # using NVML at the cost of a weaker CUDA availability assessment. Note that if NVML discovery/initialization # fails, this assessment falls back to the default CUDA Runtime API assessment (`cudaGetDeviceCount`) return device_count() > 0 else: # The default availability inspection never throws and returns 0 if the driver is missing or can't # be initialized. This uses the CUDA Runtime API `cudaGetDeviceCount` which in turn initializes the CUDA Driver # API via `cuInit` return torch._C._cuda_getDeviceCount() > 0
def is_bf16_supported(including_emulation: bool = True): r"""Return a bool indicating if the current CUDA/ROCm device supports dtype bfloat16.""" # Check for ROCm, if true return true, no ROCM_VERSION check required, # since it is supported on AMD GPU archs. if torch.version.hip: return True # If CUDA is not available, than it does not support bf16 either if not is_available(): return False device = torch.cuda.current_device() # Check for CUDA version and device compute capability. # This is a fast way to check for it. cuda_version = torch.version.cuda if ( cuda_version is not None and int(cuda_version.split(".")[0]) >= 11 and torch.cuda.get_device_properties(device).major >= 8 ): return True if not including_emulation: return False # Finally try to create a bfloat16 device. return _check_bf16_tensor_supported(device) @lru_cache(maxsize=16) def _check_bf16_tensor_supported(device: _device_t): try: torch.tensor([1.0], dtype=torch.bfloat16, device=device) return True except Exception: return False def _sleep(cycles): torch._C._cuda_sleep(cycles) def _extract_arch_version(arch_string: str): """Extracts the architecture string from a CUDA version""" base = arch_string.split("_")[1] if base.endswith("a"): base = base[:-1] return int(base) def _check_capability(): incorrect_binary_warn = """ Found GPU%d %s which requires CUDA_VERSION >= %d to work properly, but your PyTorch was compiled with CUDA_VERSION %d. Please install the correct PyTorch binary using instructions from https://pytorch.org """ # noqa: F841 old_gpu_warn = """ Found GPU%d %s which is of cuda capability %d.%d. PyTorch no longer supports this GPU because it is too old. The minimum cuda capability supported by this library is %d.%d. """ if torch.version.cuda is not None: # on ROCm we don't want this check CUDA_VERSION = torch._C._cuda_getCompiledVersion() # noqa: F841 for d in range(device_count()): capability = get_device_capability(d) major = capability[0] minor = capability[1] name = get_device_name(d) current_arch = major * 10 + minor min_arch = min( (_extract_arch_version(arch) for arch in torch.cuda.get_arch_list()), default=35, ) if current_arch < min_arch: warnings.warn( old_gpu_warn % (d, name, major, minor, min_arch // 10, min_arch % 10) ) def _check_cubins(): incompatible_device_warn = """ {} with CUDA capability sm_{} is not compatible with the current PyTorch installation. The current PyTorch install supports CUDA capabilities {}. If you want to use the {} GPU with PyTorch, please check the instructions at https://pytorch.org/get-started/locally/ """ if torch.version.cuda is None: # on ROCm we don't want this check return arch_list = get_arch_list() if len(arch_list) == 0: return supported_sm = [_extract_arch_version(arch) for arch in arch_list if "sm_" in arch] for idx in range(device_count()): cap_major, cap_minor = get_device_capability(idx) # NVIDIA GPU compute architectures are backward compatible within major version supported = any(sm // 10 == cap_major for sm in supported_sm) if not supported: device_name = get_device_name(idx) capability = cap_major * 10 + cap_minor warnings.warn( incompatible_device_warn.format( device_name, capability, " ".join(arch_list), device_name ) )
[docs]def is_initialized(): r"""Return whether PyTorch's CUDA state has been initialized.""" return _initialized and not _is_in_bad_fork()
def _lazy_call(callable, **kwargs): if is_initialized(): callable() else: # TODO(torch_deploy): this accesses linecache, which attempts to read the # file system to get traceback info. Patch linecache or do something # else here if this ends up being important. global _lazy_seed_tracker if kwargs.get("seed_all", False): _lazy_seed_tracker.queue_seed_all(callable, traceback.format_stack()) elif kwargs.get("seed", False): _lazy_seed_tracker.queue_seed(callable, traceback.format_stack()) else: # Don't store the actual traceback to avoid memory cycle _queued_calls.append((callable, traceback.format_stack())) _lazy_call(_check_capability) _lazy_call(_check_cubins) class DeferredCudaCallError(Exception): pass OutOfMemoryError = torch._C.OutOfMemoryError
[docs]def init(): r"""Initialize PyTorch's CUDA state. You may need to call this explicitly if you are interacting with PyTorch via its C API, as Python bindings for CUDA functionality will not be available until this initialization takes place. Ordinary users should not need this, as all of PyTorch's CUDA methods automatically initialize CUDA state on-demand. Does nothing if the CUDA state is already initialized. """ _lazy_init()
def _lazy_init(): global _initialized, _queued_calls if is_initialized() or hasattr(_tls, "is_initializing"): return with _initialization_lock: # We be double-checked locking, boys! This is OK because # the above test was GIL protected anyway. The inner test # is for when a thread blocked on some other thread which was # doing the initialization; when they get the lock, they will # find there is nothing left to do. if is_initialized(): return # It is important to prevent other threads from entering _lazy_init # immediately, while we are still guaranteed to have the GIL, because some # of the C calls we make below will release the GIL if _is_in_bad_fork(): raise RuntimeError( "Cannot re-initialize CUDA in forked subprocess. To use CUDA with " "multiprocessing, you must use the 'spawn' start method" ) if not hasattr(torch._C, "_cuda_getDeviceCount"): raise AssertionError("Torch not compiled with CUDA enabled") if _cudart is None: raise AssertionError( "libcudart functions unavailable. It looks like you have a broken build?" ) # This function throws if there's a driver initialization error, no GPUs # are found or any other error occurs if "CUDA_MODULE_LOADING" not in os.environ: os.environ["CUDA_MODULE_LOADING"] = "LAZY" torch._C._cuda_init() # Some of the queued calls may reentrantly call _lazy_init(); # we need to just return without initializing in that case. # However, we must not let any *other* threads in! _tls.is_initializing = True _queued_calls.extend(calls for calls in _lazy_seed_tracker.get_calls() if calls) try: for queued_call, orig_traceback in _queued_calls: try: queued_call() except Exception as e: msg = ( f"CUDA call failed lazily at initialization with error: {str(e)}\n\n" f"CUDA call was originally invoked at:\n\n{''.join(orig_traceback)}" ) raise DeferredCudaCallError(msg) from e finally: delattr(_tls, "is_initializing") _initialized = True
[docs]def cudart(): r"""Retrieves the CUDA runtime API module. This function initializes the CUDA runtime environment if it is not already initialized and returns the CUDA runtime API module (_cudart). The CUDA runtime API module provides access to various CUDA runtime functions. Args: ``None`` Returns: module: The CUDA runtime API module (_cudart). Raises: RuntimeError: If CUDA cannot be re-initialized in a forked subprocess. AssertionError: If PyTorch is not compiled with CUDA support or if libcudart functions are unavailable. Example of CUDA operations with profiling: >>> import torch >>> from torch.cuda import cudart, check_error >>> import os >>> >>> os.environ['CUDA_PROFILE'] = '1' >>> >>> def perform_cuda_operations_with_streams(): >>> stream = torch.cuda.Stream() >>> with torch.cuda.stream(stream): >>> x = torch.randn(100, 100, device='cuda') >>> y = torch.randn(100, 100, device='cuda') >>> z = torch.mul(x, y) >>> return z >>> >>> torch.cuda.synchronize() >>> print("====== Start nsys profiling ======") >>> check_error(cudart().cudaProfilerStart()) >>> with torch.autograd.profiler.emit_nvtx(): >>> result = perform_cuda_operations_with_streams() >>> print("CUDA operations completed.") >>> check_error(torch.cuda.cudart().cudaProfilerStop()) >>> print("====== End nsys profiling ======") To run this example and save the profiling information, execute: >>> $ nvprof --profile-from-start off --csv --print-summary -o trace_name.prof -f -- python cudart_test.py This command profiles the CUDA operations in the provided script and saves the profiling information to a file named `trace_name.prof`. The `--profile-from-start off` option ensures that profiling starts only after the `cudaProfilerStart` call in the script. The `--csv` and `--print-summary` options format the profiling output as a CSV file and print a summary, respectively. The `-o` option specifies the output file name, and the `-f` option forces the overwrite of the output file if it already exists. """ _lazy_init() return _cudart
class cudaStatus: SUCCESS: int = 0 ERROR_NOT_READY: int = 34 class CudaError(RuntimeError): def __init__(self, code: int) -> None: msg = _cudart.cudaGetErrorString(_cudart.cudaError(code)) super().__init__(f"{msg} ({code})") def check_error(res: int) -> None: if res != _cudart.cudaError.success: raise CudaError(res) class _DeviceGuard: def __init__(self, index: int): self.idx = index self.prev_idx = -1 def __enter__(self): self.prev_idx = torch.cuda._exchange_device(self.idx) def __exit__(self, type: Any, value: Any, traceback: Any): self.idx = torch.cuda._maybe_exchange_device(self.prev_idx) return False
[docs]class device: r"""Context-manager that changes the selected device. Args: device (torch.device or int): device index to select. It's a no-op if this argument is a negative integer or ``None``. """ def __init__(self, device: Any): self.idx = _get_device_index(device, optional=True) self.prev_idx = -1 def __enter__(self): self.prev_idx = torch.cuda._exchange_device(self.idx) def __exit__(self, type: Any, value: Any, traceback: Any): self.idx = torch.cuda._maybe_exchange_device(self.prev_idx) return False
[docs]class device_of(device): r"""Context-manager that changes the current device to that of given object. You can use both tensors and storages as arguments. If a given object is not allocated on a GPU, this is a no-op. Args: obj (Tensor or Storage): object allocated on the selected device. """ def __init__(self, obj): idx = obj.get_device() if obj.is_cuda else -1 super().__init__(idx)
[docs]def set_device(device: _device_t) -> None: r"""Set the current device. Usage of this function is discouraged in favor of :any:`device`. In most cases it's better to use ``CUDA_VISIBLE_DEVICES`` environmental variable. Args: device (torch.device or int): selected device. This function is a no-op if this argument is negative. """ device = _get_device_index(device) if device >= 0: torch._C._cuda_setDevice(device)
[docs]def get_device_name(device: Optional[_device_t] = None) -> str: r"""Get the name of a device. Args: device (torch.device or int or str, optional): device for which to return the name. This function is a no-op if this argument is a negative integer. It uses the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). Returns: str: the name of the device """ return get_device_properties(device).name
[docs]def get_device_capability(device: Optional[_device_t] = None) -> Tuple[int, int]: r"""Get the cuda capability of a device. Args: device (torch.device or int or str, optional): device for which to return the device capability. This function is a no-op if this argument is a negative integer. It uses the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). Returns: tuple(int, int): the major and minor cuda capability of the device """ prop = get_device_properties(device) return prop.major, prop.minor
[docs]def get_device_properties(device: Optional[_device_t] = None) -> _CudaDeviceProperties: r"""Get the properties of a device. Args: device (torch.device or int or str, optional): device for which to return the properties of the device. It uses the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). Returns: _CudaDeviceProperties: the properties of the device """ _lazy_init() # will define _get_device_properties device = _get_device_index(device, optional=True) if device < 0 or device >= device_count(): raise AssertionError("Invalid device id") return _get_device_properties(device) # type: ignore[name-defined]
[docs]def can_device_access_peer(device: _device_t, peer_device: _device_t) -> bool: r"""Check if peer access between two devices is possible.""" _lazy_init() device = _get_device_index(device, optional=True) peer_device = _get_device_index(peer_device) if device < 0 or device >= device_count(): raise AssertionError("Invalid device id") if peer_device < 0 or peer_device >= device_count(): raise AssertionError("Invalid peer device id") return torch._C._cuda_canDeviceAccessPeer(device, peer_device)
[docs]class StreamContext: r"""Context-manager that selects a given stream. All CUDA kernels queued within its context will be enqueued on a selected stream. Args: Stream (Stream): selected stream. This manager is a no-op if it's ``None``. .. note:: Streams are per-device. """ cur_stream: Optional["torch.cuda.Stream"] def __init__(self, stream: Optional["torch.cuda.Stream"]): self.stream = stream self.idx = _get_device_index(None, True) if not torch.jit.is_scripting(): if self.idx is None: self.idx = -1 self.src_prev_stream = ( None if not torch.jit.is_scripting() else torch.cuda.default_stream(None) ) self.dst_prev_stream = ( None if not torch.jit.is_scripting() else torch.cuda.default_stream(None) ) def __enter__(self): # Local cur_stream variable for type refinement cur_stream = self.stream # Return if stream is None or CUDA device not available if cur_stream is None or self.idx == -1: return self.src_prev_stream = torch.cuda.current_stream(None) # If the stream is not on the current device, then # set the current stream on the device if self.src_prev_stream.device != cur_stream.device: with device(cur_stream.device): self.dst_prev_stream = torch.cuda.current_stream(cur_stream.device) torch.cuda.set_stream(cur_stream) def __exit__(self, type: Any, value: Any, traceback: Any): # Local cur_stream variable for type refinement cur_stream = self.stream # If stream is None or no CUDA device available, return if cur_stream is None or self.idx == -1: return # Reset the stream on the original device # and destination device if self.src_prev_stream.device != cur_stream.device: # type: ignore[union-attr] torch.cuda.set_stream(self.dst_prev_stream) # type: ignore[arg-type] torch.cuda.set_stream(self.src_prev_stream) # type: ignore[arg-type]
[docs]def stream(stream: Optional["torch.cuda.Stream"]) -> StreamContext: r"""Wrap around the Context-manager StreamContext that selects a given stream. Arguments: stream (Stream): selected stream. This manager is a no-op if it's ``None``. ..Note:: In eager mode stream is of type Stream class while in JIT it is an object of the custom class ``torch.classes.cuda.Stream``. """ return StreamContext(stream)
def _set_stream_by_id(stream_id, device_index, device_type): r"""set stream specified by the stream id, device index and device type Args: stream_id (int): stream id in stream pool device_index (int): device index in topo device_type (int): enum device type """ torch._C._cuda_setStream( stream_id=stream_id, device_index=device_index, device_type=device_type, )
[docs]def set_stream(stream: Stream): r"""Set the current stream.This is a wrapper API to set the stream. Usage of this function is discouraged in favor of the ``stream`` context manager. Args: stream (Stream): selected stream. This function is a no-op if this argument is ``None``. """ if stream is None: return _set_stream_by_id( stream_id=stream.stream_id, device_index=stream.device_index, device_type=stream.device_type, )
def _parse_visible_devices() -> Union[List[int], List[str]]: r"""Parse CUDA_VISIBLE_DEVICES environment variable.""" var = os.getenv("CUDA_VISIBLE_DEVICES") if torch.version.hip: hip_devices = os.getenv("HIP_VISIBLE_DEVICES") if hip_devices is not None: var = hip_devices if var is None: return list(range(64)) def _strtoul(s: str) -> int: """Return -1 or positive integer sequence string starts with.""" if not s: return -1 for idx, c in enumerate(s): if not (c.isdigit() or (idx == 0 and c in "+-")): break if idx + 1 == len(s): idx += 1 return int(s[:idx]) if idx > 0 else -1 def parse_list_with_prefix(lst: str, prefix: str) -> List[str]: rcs: List[str] = [] for elem in lst.split(","): # Repeated id results in empty set if elem in rcs: return cast(List[str], []) # Anything other but prefix is ignored if not elem.startswith(prefix): break rcs.append(elem) return rcs if var.startswith("GPU-"): return parse_list_with_prefix(var, "GPU-") if var.startswith("MIG-"): return parse_list_with_prefix(var, "MIG-") # CUDA_VISIBLE_DEVICES uses something like strtoul # which makes `1gpu2,2ampere` is equivalent to `1,2` rc: List[int] = [] for elem in var.split(","): x = _strtoul(elem.strip()) # Repeated ordinal results in empty set if x in rc: return cast(List[int], []) # Negative value aborts the sequence if x < 0: break rc.append(x) return rc def _raw_device_count_amdsmi() -> int: if not _HAS_PYNVML: # If amdsmi is not available return -1 try: amdsmi.amdsmi_init() except amdsmi.AmdSmiException as e: warnings.warn(f"Can't initialize amdsmi - Error code: {e.err_code}") return -1 socket_handles = amdsmi.amdsmi_get_processor_handles() return len(socket_handles) def _raw_device_count_nvml() -> int: r"""Return number of devices as reported by NVML or negative value if NVML discovery/initialization failed.""" from ctypes import byref, c_int, CDLL nvml_h = CDLL("libnvidia-ml.so.1") rc = nvml_h.nvmlInit() if rc != 0: warnings.warn("Can't initialize NVML") return -1 dev_count = c_int(-1) rc = nvml_h.nvmlDeviceGetCount_v2(byref(dev_count)) if rc != 0: warnings.warn("Can't get nvml device count") return -1 del nvml_h return dev_count.value def _raw_device_uuid_amdsmi() -> Optional[List[str]]: from ctypes import byref, c_int, c_void_p, CDLL, create_string_buffer if not _HAS_PYNVML: # If amdsmi is not available return None try: amdsmi.amdsmi_init() except amdsmi.AmdSmiException: warnings.warn("Can't initialize amdsmi") return None try: socket_handles = amdsmi.amdsmi_get_processor_handles() dev_count = len(socket_handles) except amdsmi.AmdSmiException: warnings.warn("Can't get amdsmi device count") return None uuids: List[str] = [] for idx in range(dev_count): try: handler = amdsmi.amdsmi_get_processor_handles()[idx] except amdsmi.AmdSmiException: warnings.warn("Cannot get amd device handler") return None try: uuid = amdsmi.amdsmi_get_gpu_asic_info(handler)["asic_serial"][ 2: ] # Removes 0x prefix from serial except amdsmi.AmdSmiException: warnings.warn("Cannot get uuid for amd device") return None uuids.append( str(uuid).lower() ) # Lower-case to match expected HIP_VISIBLE_DEVICES uuid input return uuids def _raw_device_uuid_nvml() -> Optional[List[str]]: r"""Return list of device UUID as reported by NVML or None if NVM discovery/initialization failed.""" from ctypes import byref, c_int, c_void_p, CDLL, create_string_buffer nvml_h = CDLL("libnvidia-ml.so.1") rc = nvml_h.nvmlInit() if rc != 0: warnings.warn("Can't initialize NVML") return None dev_count = c_int(-1) rc = nvml_h.nvmlDeviceGetCount_v2(byref(dev_count)) if rc != 0: warnings.warn("Can't get nvml device count") return None uuids: List[str] = [] for idx in range(dev_count.value): dev_id = c_void_p() rc = nvml_h.nvmlDeviceGetHandleByIndex_v2(idx, byref(dev_id)) if rc != 0: warnings.warn("Can't get device handle") return None buf_len = 96 buf = create_string_buffer(buf_len) rc = nvml_h.nvmlDeviceGetUUID(dev_id, buf, buf_len) if rc != 0: warnings.warn("Can't get device UUID") return None uuids.append(buf.raw.decode("ascii").strip("\0")) del nvml_h return uuids def _transform_uuid_to_ordinals(candidates: List[str], uuids: List[str]) -> List[int]: r"""Given the set of partial uuids and list of known uuids builds a set of ordinals excluding ambiguous partials IDs.""" def uuid_to_ordinal(candidate: str, uuids: List[str]) -> int: best_match = -1 for idx, uuid in enumerate(uuids): if not uuid.startswith(candidate): continue # Ambiguous candidate if best_match != -1: return -1 best_match = idx return best_match rc: List[int] = [] for candidate in candidates: if torch.version.hip: candidate = candidate.replace( "GPU-", "", 1 ) # Remove GPU-prefix to match amdsmi asic serial idx = uuid_to_ordinal(candidate, uuids) # First invalid ordinal stops parsing if idx < 0: break # Duplicates result in empty set if idx in rc: return cast(List[int], []) rc.append(idx) return rc def _device_count_amdsmi() -> int: visible_devices = _parse_visible_devices() if not visible_devices: return 0 try: if type(visible_devices[0]) is str: uuids = _raw_device_uuid_amdsmi() if uuids is None: return -1 # Create string version of visible devices to avoid mypy warnings visible_device_str = cast(List[str], visible_devices) visible_devices = _transform_uuid_to_ordinals(visible_device_str, uuids) else: raw_cnt = _raw_device_count_amdsmi() if raw_cnt <= 0: return raw_cnt # Trim the list up to a maximum available device for idx, val in enumerate(visible_devices): if cast(int, val) >= raw_cnt: return idx except OSError: return -1 except AttributeError: return -1 return len(visible_devices) def _device_count_nvml() -> int: r"""Return number of devices as reported by NVML taking CUDA_VISIBLE_DEVICES into account. Negative value is returned if NVML discovery or initialization has failed. """ visible_devices = _parse_visible_devices() if not visible_devices: return 0 try: if type(visible_devices[0]) is str: # Skip MIG parsing if visible_devices[0].startswith("MIG-"): return -1 uuids = _raw_device_uuid_nvml() if uuids is None: return -1 visible_devices = _transform_uuid_to_ordinals( cast(List[str], visible_devices), uuids ) else: raw_cnt = _raw_device_count_nvml() if raw_cnt <= 0: return raw_cnt # Trim the list up to a maximum available device for idx, val in enumerate(visible_devices): if cast(int, val) >= raw_cnt: return idx except OSError: return -1 except AttributeError: return -1 return len(visible_devices) def _get_nvml_device_index(device: Optional[Union[int, Device]]) -> int: r"""Return the NVML index of the device, taking CUDA_VISIBLE_DEVICES into account.""" idx = _get_device_index(device, optional=True) visible_devices = _parse_visible_devices() if type(visible_devices[0]) is str: uuids = _raw_device_uuid_nvml() if uuids is None: raise RuntimeError("Can't get device UUIDs") visible_devices = _transform_uuid_to_ordinals( cast(List[str], visible_devices), uuids ) visible_devices = cast(List[int], visible_devices) if idx < 0 or idx >= len(visible_devices): raise RuntimeError( f"device {idx} is not visible (CUDA_VISIBLE_DEVICES={visible_devices})" ) return visible_devices[idx] _cached_device_count: Optional[int] = None
[docs]def device_count() -> int: r"""Return the number of GPUs available.""" global _cached_device_count if not _is_compiled(): return 0 if _cached_device_count is not None: return _cached_device_count # bypass _device_count_nvml() if rocm (not supported) nvml_count = _device_count_amdsmi() if torch.version.hip else _device_count_nvml() r = torch._C._cuda_getDeviceCount() if nvml_count < 0 else nvml_count # NB: Do not cache the device count prior to CUDA initialization, because # the number of devices can change due to changes to CUDA_VISIBLE_DEVICES # setting prior to CUDA initialization. if _initialized: _cached_device_count = r return r
[docs]def get_arch_list() -> List[str]: r"""Return list CUDA architectures this library was compiled for.""" if not is_available(): return [] arch_flags = torch._C._cuda_getArchFlags() if arch_flags is None: return [] return arch_flags.split()
[docs]def get_gencode_flags() -> str: r"""Return NVCC gencode flags this library was compiled with.""" arch_list = get_arch_list() if len(arch_list) == 0: return "" arch_list_ = [arch.split("_") for arch in arch_list] return " ".join( [ f"-gencode compute=compute_{arch},code={kind}_{arch}" for (kind, arch) in arch_list_ ] )
[docs]def current_device() -> int: r"""Return the index of a currently selected device.""" _lazy_init() return torch._C._cuda_getDevice()
[docs]def synchronize(device: _device_t = None) -> None: r"""Wait for all kernels in all streams on a CUDA device to complete. Args: device (torch.device or int, optional): device for which to synchronize. It uses the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). """ _lazy_init() with torch.cuda.device(device): return torch._C._cuda_synchronize()
[docs]def ipc_collect(): r"""Force collects GPU memory after it has been released by CUDA IPC. .. note:: Checks if any sent CUDA tensors could be cleaned from the memory. Force closes shared memory file used for reference counting if there is no active counters. Useful when the producer process stopped actively sending tensors and want to release unused memory. """ _lazy_init() return torch._C._cuda_ipc_collect()
[docs]def current_stream(device: Optional[_device_t] = None) -> Stream: r"""Return the currently selected :class:`Stream` for a given device. Args: device (torch.device or int, optional): selected device. Returns the currently selected :class:`Stream` for the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). """ _lazy_init() streamdata = torch._C._cuda_getCurrentStream( _get_device_index(device, optional=True) ) return Stream( stream_id=streamdata[0], device_index=streamdata[1], device_type=streamdata[2] )
[docs]def default_stream(device: Optional[_device_t] = None) -> Stream: r"""Return the default :class:`Stream` for a given device. Args: device (torch.device or int, optional): selected device. Returns the default :class:`Stream` for the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). """ _lazy_init() streamdata = torch._C._cuda_getDefaultStream( _get_device_index(device, optional=True) ) return Stream( stream_id=streamdata[0], device_index=streamdata[1], device_type=streamdata[2] )
[docs]def current_blas_handle(): r"""Return cublasHandle_t pointer to current cuBLAS handle""" _lazy_init() return torch._C._cuda_getCurrentBlasHandle()
[docs]def set_sync_debug_mode(debug_mode: Union[int, str]) -> None: r"""Set the debug mode for cuda synchronizing operations. Args: debug_mode(str or int): if "default" or 0, don't error or warn on synchronizing operations, if "warn" or 1, warn on synchronizing operations, if "error" or 2, error out synchronizing operations. Warning: This is an experimental feature, and not all synchronizing operations will trigger warning or error. In particular, operations in torch.distributed and torch.sparse namespaces are not covered yet. """ _lazy_init() if isinstance(debug_mode, str): if debug_mode == "default": debug_mode = 0 elif debug_mode == "warn": debug_mode = 1 elif debug_mode == "error": debug_mode = 2 else: raise RuntimeError( "invalid value of debug_mode, expected one of `default`, `warn`, `error`" ) torch._C._cuda_set_sync_debug_mode(debug_mode)
[docs]def get_sync_debug_mode() -> int: r"""Return current value of debug mode for cuda synchronizing operations.""" _lazy_init() return torch._C._cuda_get_sync_debug_mode()
def _get_pynvml_handler(device: Optional[Union[Device, int]] = None): if not _HAS_PYNVML: raise ModuleNotFoundError( "pynvml does not seem to be installed or it can't be imported." ) from _PYNVML_ERR from pynvml import NVMLError_DriverNotLoaded try: pynvml.nvmlInit() except NVMLError_DriverNotLoaded as e: raise RuntimeError("cuda driver can't be loaded, is cuda enabled?") from e device = _get_nvml_device_index(device) handle = pynvml.nvmlDeviceGetHandleByIndex(device) return handle def _get_amdsmi_handler(device: Optional[Union[Device, int]] = None): if not _HAS_PYNVML: raise ModuleNotFoundError( "amdsmi does not seem to be installed or it can't be imported." ) from _PYNVML_ERR try: amdsmi.amdsmi_init() except amdsmi.AmdSmiException as e: raise RuntimeError( "amdsmi driver can't be loaded, requires >=ROCm5.6 installation" ) from e device = _get_amdsmi_device_index(device) handle = amdsmi.amdsmi_get_processor_handles()[device] return handle def _get_amdsmi_device_index(device: Optional[Union[int, Device]]) -> int: r"""Return the amdsmi index of the device, taking visible_devices into account.""" idx = _get_device_index(device, optional=True) visible_devices = _parse_visible_devices() if type(visible_devices[0]) is str: uuids = _raw_device_uuid_amdsmi() if uuids is None: raise RuntimeError("Can't get device UUIDs") visible_devices_str = cast( List[str], visible_devices ) # Create str variable for mypy visible_devices = _transform_uuid_to_ordinals(visible_devices_str, uuids) idx_map = dict(enumerate(cast(List[int], visible_devices))) if idx not in idx_map: raise RuntimeError( f"device {idx} is not visible (HIP_VISIBLE_DEVICES={visible_devices})" ) return idx_map[idx] def _get_amdsmi_device_memory_used(device: Optional[Union[Device, int]] = None) -> int: handle = _get_amdsmi_handler() device = _get_amdsmi_device_index(device) # amdsmi_get_gpu_vram_usage returns mem usage in megabytes mem_mega_bytes = amdsmi.amdsmi_get_gpu_vram_usage(handle)["vram_used"] mem_bytes = mem_mega_bytes * 1024 * 1024 return mem_bytes def _get_amdsmi_memory_usage(device: Optional[Union[Device, int]] = None) -> int: handle = _get_amdsmi_handler() device = _get_amdsmi_device_index(device) handle = amdsmi.amdsmi_get_processor_handles()[device] return amdsmi.amdsmi_get_gpu_activity(handle)["umc_activity"] def _get_amdsmi_utilization(device: Optional[Union[Device, int]] = None) -> int: handle = _get_amdsmi_handler() device = _get_amdsmi_device_index(device) handle = amdsmi.amdsmi_get_processor_handles()[device] return amdsmi.amdsmi_get_gpu_activity(handle)["gfx_activity"] def _get_amdsmi_temperature(device: Optional[Union[Device, int]] = None) -> int: handle = _get_amdsmi_handler(device) return amdsmi.amdsmi_get_temp_metric( handle, amdsmi.AmdSmiTemperatureType.JUNCTION, amdsmi.AmdSmiTemperatureMetric.CURRENT, ) def _get_amdsmi_power_draw(device: Optional[Union[Device, int]] = None) -> int: handle = _get_amdsmi_handler(device) socket_power = amdsmi.amdsmi_get_power_info(handle)["average_socket_power"] if socket_power != "N/A": return socket_power else: return amdsmi.amdsmi_get_power_info(handle)["current_socket_power"] def _get_amdsmi_clock_rate(device: Optional[Union[Device, int]] = None) -> int: handle = _get_amdsmi_handler(device) clock_info = amdsmi.amdsmi_get_clock_info(handle, amdsmi.AmdSmiClkType.GFX) if "cur_clk" in clock_info: # ROCm 6.2 deprecation return clock_info["cur_clk"] else: return clock_info["clk"]
[docs]def device_memory_used(device: Optional[Union[Device, int]] = None) -> int: r"""Return used global (device) memory in bytes as given by `nvidia-smi` or `amd-smi`. Args: device (torch.device or int, optional): selected device. Returns statistic for the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). """ if not torch.version.hip: handle = _get_pynvml_handler() device = _get_nvml_device_index(device) handle = pynvml.nvmlDeviceGetHandleByIndex(device) return pynvml.nvmlDeviceGetMemoryInfo(handle).used else: return _get_amdsmi_device_memory_used(device)
[docs]def memory_usage(device: Optional[Union[Device, int]] = None) -> int: r"""Return the percent of time over the past sample period during which global (device) memory was being read or written as given by `nvidia-smi`. Args: device (torch.device or int, optional): selected device. Returns statistic for the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). Warning: Each sample period may be between 1 second and 1/6 second, depending on the product being queried. """ if not torch.version.hip: handle = _get_pynvml_handler() device = _get_nvml_device_index(device) handle = pynvml.nvmlDeviceGetHandleByIndex(device) return pynvml.nvmlDeviceGetUtilizationRates(handle).memory else: return _get_amdsmi_memory_usage(device)
[docs]def utilization(device: Optional[Union[Device, int]] = None) -> int: r"""Return the percent of time over the past sample period during which one or more kernels was executing on the GPU as given by `nvidia-smi`. Args: device (torch.device or int, optional): selected device. Returns statistic for the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). Warning: Each sample period may be between 1 second and 1/6 second, depending on the product being queried. """ if not torch.version.hip: handle = _get_pynvml_handler(device) device = _get_nvml_device_index(device) handle = pynvml.nvmlDeviceGetHandleByIndex(device) return pynvml.nvmlDeviceGetUtilizationRates(handle).gpu else: return _get_amdsmi_utilization(device)
[docs]def temperature(device: Optional[Union[Device, int]] = None) -> int: r"""Return the average temperature of the GPU sensor in Degrees C (Centigrades). The average temperature is computed based on past sample period as given by `nvidia-smi`. Args: device (torch.device or int, optional): selected device. Returns statistic for the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). Warning: Each sample period may be between 1 second and 1/6 second, depending on the product being queried. """ if not torch.version.hip: handle = _get_pynvml_handler(device) # 0 refers to the temperature sensor for the GPU die. return pynvml.nvmlDeviceGetTemperature(handle, 0) else: return _get_amdsmi_temperature(device)
[docs]def power_draw(device: Optional[Union[Device, int]] = None) -> int: r"""Return the average power draw of the GPU sensor in mW (MilliWatts) over the past sample period as given by `nvidia-smi` for Fermi or newer fully supported devices. Args: device (torch.device or int, optional): selected device. Returns statistic for the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). Warning: Each sample period may be between 1 second and 1/6 second, depending on the product being queried. """ if not torch.version.hip: handle = _get_pynvml_handler(device) return pynvml.nvmlDeviceGetPowerUsage(handle) else: return _get_amdsmi_power_draw(device)
[docs]def clock_rate(device: Optional[Union[Device, int]] = None) -> int: r"""Return the clock speed of the GPU SM in Hz Hertz over the past sample period as given by `nvidia-smi`. Args: device (torch.device or int, optional): selected device. Returns statistic for the current device, given by :func:`~torch.cuda.current_device`, if :attr:`device` is ``None`` (default). Warning: Each sample period may be between 1 second and 1/6 second, depending on the product being queried. """ if not torch.version.hip: handle = _get_pynvml_handler(device) return pynvml.nvmlDeviceGetClockInfo(handle, 1) else: return _get_amdsmi_clock_rate(device)
def _get_device(device: Union[int, str, torch.device]) -> torch.device: r"""Return the torch.device type object from the passed in device. Args: device (torch.device or int): selected device. """ if isinstance(device, str): device = torch.device(device) elif isinstance(device, int): device = torch.device("cuda", device) return device def _get_generator(device: torch.device) -> torch._C.Generator: r"""Return the CUDA Generator object for the given device. Args: device (torch.device): selected device. """ idx = device.index if idx is None: idx = current_device() return torch.cuda.default_generators[idx] def _set_rng_state_offset( offset: int, device: Union[int, str, torch.device] = "cuda" ) -> None: r"""Set the random number generator state offset of the specified GPU. Args: offset (int): The desired offset device (torch.device or int, optional): The device to set the RNG state. Default: ``'cuda'`` (i.e., ``torch.device('cuda')``, the current CUDA device). """ final_device = _get_device(device) def cb(): default_generator = _get_generator(final_device) default_generator.set_offset(offset) _lazy_call(cb) def _get_rng_state_offset(device: Union[int, str, torch.device] = "cuda") -> int: r"""Return the random number generator state offset of the specified GPU. Args: device (torch.device or int, optional): The device to return the RNG state offset of. Default: ``'cuda'`` (i.e., ``torch.device('cuda')``, the current CUDA device). .. warning:: This function eagerly initializes CUDA. """ _lazy_init() final_device = _get_device(device) default_generator = _get_generator(final_device) return default_generator.get_offset() from .memory import * # noqa: F403 from .random import * # noqa: F403 ################################################################################ # Define Storage and Tensor classes ################################################################################ @staticmethod # type: ignore[misc] def _lazy_new(cls, *args, **kwargs): _lazy_init() # We may need to call lazy init again if we are a forked child # del _CudaBase.__new__ return super(_CudaBase, cls).__new__(cls, *args, **kwargs) class _CudaBase: is_cuda = True is_sparse = False def type(self, *args, **kwargs): # We could use a Protocol here to tell mypy that self has `get_device` method # but it is only available in the typing module on Python >= 3.8 # or on typing_extensions module on Python >= 3.6 with device(self.get_device()): # type: ignore[attr-defined] return super().type(*args, **kwargs) # type: ignore[misc] __new__ = _lazy_new from torch.storage import _LegacyStorage, _warn_typed_storage_removal class _CudaLegacyStorage(_LegacyStorage): @classmethod def from_buffer(cls, *args, **kwargs): _warn_typed_storage_removal() raise RuntimeError("from_buffer: Not available for CUDA storage") @classmethod def _new_with_weak_ptr(cls, *args, **kwargs): raise RuntimeError("_new_with_weak_ptr: Not available for CUDA storage") @classmethod def _new_shared_filename(cls, manager, obj, size, *, device=None, dtype=None): raise RuntimeError("_new_shared_filename: Not available for CUDA storage") class ByteStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.uint8 class DoubleStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.double class FloatStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.float class HalfStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.half class LongStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.long class IntStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.int class ShortStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.short class CharStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.int8 class BoolStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.bool class BFloat16Storage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.bfloat16 class ComplexDoubleStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.cdouble class ComplexFloatStorage(_CudaLegacyStorage): @classproperty def dtype(self): _warn_typed_storage_removal() return self._dtype @classproperty def _dtype(self): return torch.cfloat del _LegacyStorage del _CudaLegacyStorage torch._storage_classes.add(DoubleStorage) torch._storage_classes.add(FloatStorage) torch._storage_classes.add(LongStorage) torch._storage_classes.add(IntStorage) torch._storage_classes.add(ShortStorage) torch._storage_classes.add(CharStorage) torch._storage_classes.add(ByteStorage) torch._storage_classes.add(HalfStorage) torch._storage_classes.add(BoolStorage) torch._storage_classes.add(BFloat16Storage) torch._storage_classes.add(ComplexDoubleStorage) torch._storage_classes.add(ComplexFloatStorage) class _WrappedTritonKernel: """Just a simple wrapper to store some metadata for testing purposes.""" def __init__(self, kernel): self.kernel = kernel self.kernel_invoked = False def __call__(self, *args, **kwargs): res = self.kernel(*args, **kwargs) self.kernel_invoked = True return res def _register_triton_kernels(): if torch._running_with_deploy(): return @_WrappedTritonKernel def kernel_impl(*args, **kwargs): from torch.sparse._triton_ops import bsr_dense_mm return bsr_dense_mm(*args, skip_checks=True, **kwargs) @_WrappedTritonKernel def addmm_kernel_impl(*args, **kwargs): from torch.sparse._triton_ops import bsr_dense_addmm return bsr_dense_addmm(*args, skip_checks=True, **kwargs) has_triton = importlib.util.find_spec("triton") is not None if has_triton: torch._TritonLibrary.registerOp( "_triton_bsr_dense_mm_out", "_triton_bsr_dense_mm_out(Tensor bsr, Tensor dense, *, Tensor(a!) out) -> Tensor(a!)", kernel_impl, "SparseCsrCUDA", ) torch._TritonLibrary.registerOp( "_triton_bsr_dense_addmm_out", ( "_triton_bsr_dense_addmm_out(Tensor input, Tensor bsr, Tensor dense," " *, Scalar beta, Scalar alpha, Tensor(a!) out) -> Tensor(a!)" ), addmm_kernel_impl, "SparseCsrCUDA", ) _lazy_call(_register_triton_kernels) from . import amp, jiterator, nvtx, profiler, sparse, tunable __all__ = [ # Typed storage and tensors "BFloat16Storage", "BFloat16Tensor", "BoolStorage", "BoolTensor", "ByteStorage", "ByteTensor", "CharStorage", "CharTensor", "ComplexDoubleStorage", "ComplexFloatStorage", "DoubleStorage", "DoubleTensor", "FloatStorage", "FloatTensor", "HalfStorage", "HalfTensor", "IntStorage", "IntTensor", "LongStorage", "LongTensor", "ShortStorage", "ShortTensor", "CUDAGraph", "CudaError", "DeferredCudaCallError", "Event", "ExternalStream", "Stream", "StreamContext", "amp", "caching_allocator_alloc", "caching_allocator_delete", "caching_allocator_enable", "can_device_access_peer", "check_error", "cudaStatus", "cudart", "current_blas_handle", "current_device", "current_stream", "default_generators", "default_stream", "device", "device_count", "device_memory_used", "device_of", "empty_cache", "get_allocator_backend", "CUDAPluggableAllocator", "change_current_allocator", "get_arch_list", "get_device_capability", "get_device_name", "get_device_properties", "get_gencode_flags", "get_per_process_memory_fraction", "get_rng_state", "get_rng_state_all", "get_sync_debug_mode", "graph", "graph_pool_handle", "graphs", "has_half", "has_magma", "init", "initial_seed", "ipc_collect", "is_available", "is_bf16_supported", "is_current_stream_capturing", "is_initialized", "jiterator", "list_gpu_processes", "make_graphed_callables", "manual_seed", "manual_seed_all", "max_memory_allocated", "max_memory_cached", "max_memory_reserved", "mem_get_info", "memory", "memory_allocated", "memory_cached", "memory_reserved", "memory_snapshot", "memory_stats", "memory_stats_as_nested_dict", "memory_summary", "memory_usage", "MemPool", "MemPoolContext", "use_mem_pool", "temperature", "power_draw", "clock_rate", "nccl", "nvtx", "profiler", "random", "reset_accumulated_memory_stats", "reset_max_memory_allocated", "reset_max_memory_cached", "reset_peak_memory_stats", "seed", "seed_all", "set_device", "set_per_process_memory_fraction", "set_rng_state", "set_rng_state_all", "set_stream", "set_sync_debug_mode", "sparse", "stream", "streams", "synchronize", "tunable", "utilization", ]

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