Source code for torch.backends.cudnn

import sys
import torch
import warnings
from contextlib import contextmanager
from torch.backends import ContextProp, PropModule, __allow_nonbracketed_mutation

    from torch._C import _cudnn
except ImportError:
    _cudnn = None  # type: ignore[assignment]

# Write:
#   torch.backends.cudnn.enabled = False
# to globally disable CuDNN/MIOpen

__cudnn_version = None

if _cudnn is not None:
    def _init():
        global __cudnn_version
        if __cudnn_version is None:
            __cudnn_version = _cudnn.getVersionInt()
            runtime_version = _cudnn.getRuntimeVersion()
            compile_version = _cudnn.getCompileVersion()
            runtime_major, runtime_minor, _ = runtime_version
            compile_major, compile_minor, _ = compile_version
            # Different major versions are always incompatible
            # Starting with cuDNN 7, minor versions are backwards-compatible
            # Not sure about MIOpen (ROCm), so always do a strict check
            if runtime_major != compile_major:
                cudnn_compatible = False
            elif runtime_major < 7 or not _cudnn.is_cuda:
                cudnn_compatible = runtime_minor == compile_minor
                cudnn_compatible = runtime_minor >= compile_minor
            if not cudnn_compatible:
                raise RuntimeError(
                    'cuDNN version incompatibility: PyTorch was compiled against {} '
                    'but linked against {}'.format(compile_version, runtime_version))
        return True
    def _init():
        return False

[docs]def version(): """Returns the version of cuDNN""" if not _init(): return None return __cudnn_version
CUDNN_TENSOR_DTYPES = { torch.half, torch.float, torch.double, }
[docs]def is_available(): r"""Returns a bool indicating if CUDNN is currently available.""" return torch._C.has_cudnn
def is_acceptable(tensor): if not torch._C._get_cudnn_enabled(): return False if tensor.device.type != 'cuda' or tensor.dtype not in CUDNN_TENSOR_DTYPES: return False if not is_available(): warnings.warn( "PyTorch was compiled without cuDNN/MIOpen support. To use cuDNN/MIOpen, rebuild " "PyTorch making sure the library is visible to the build system.") return False if not _init(): warnings.warn('cuDNN/MIOpen library not found. Check your {libpath}'.format( libpath={ 'darwin': 'DYLD_LIBRARY_PATH', 'win32': 'PATH' }.get(sys.platform, 'LD_LIBRARY_PATH'))) return False return True def set_flags(_enabled=None, _benchmark=None, _deterministic=None, _allow_tf32=None): orig_flags = (torch._C._get_cudnn_enabled(), torch._C._get_cudnn_benchmark(), torch._C._get_cudnn_deterministic(), torch._C._get_cudnn_allow_tf32()) if _enabled is not None: torch._C._set_cudnn_enabled(_enabled) if _benchmark is not None: torch._C._set_cudnn_benchmark(_benchmark) if _deterministic is not None: torch._C._set_cudnn_deterministic(_deterministic) if _allow_tf32 is not None: torch._C._set_cudnn_allow_tf32(_allow_tf32) return orig_flags @contextmanager def flags(enabled=False, benchmark=False, deterministic=False, allow_tf32=True): with __allow_nonbracketed_mutation(): orig_flags = set_flags(enabled, benchmark, deterministic, allow_tf32) try: yield finally: # recover the previous values with __allow_nonbracketed_mutation(): set_flags(*orig_flags) # The magic here is to allow us to intercept code like this: # # torch.backends.<cudnn|mkldnn>.enabled = True class CudnnModule(PropModule): def __init__(self, m, name): super(CudnnModule, self).__init__(m, name) enabled = ContextProp(torch._C._get_cudnn_enabled, torch._C._set_cudnn_enabled) deterministic = ContextProp(torch._C._get_cudnn_deterministic, torch._C._set_cudnn_deterministic) benchmark = ContextProp(torch._C._get_cudnn_benchmark, torch._C._set_cudnn_benchmark) allow_tf32 = ContextProp(torch._C._get_cudnn_allow_tf32, torch._C._set_cudnn_allow_tf32) # This is the sys.modules replacement trick, see # sys.modules[__name__] = CudnnModule(sys.modules[__name__], __name__) # Add type annotation for the replaced module enabled: bool deterministic: bool benchmark: bool


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