1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141
|
from typing import Optional
import torch
import torch.nn.intrinsic as nni
from torch.ao.nn.sparse.quantized import linear
from torch.ao.nn.sparse.quantized.utils import LinearBlockSparsePattern
from torch.ao.nn.quantized.modules.utils import _quantize_weight, hide_packed_params_repr
__all__ = ['Linear']
class Linear(torch.nn.Module):
r"""
A dynamically quantized sparse linear module with float tensor as inputs and outputs.
"""
_version = 1
_op_type = "sparse_dynamic"
_FLOAT_MODULE = torch.nn.Linear
def __init__(self, in_features, out_features, row_block_size, col_block_size, bias=True, dtype=torch.qint8):
super().__init__()
if dtype != torch.qint8:
raise NotImplementedError("Only QINT8 is supported for Sparse Quantized Linear Dynamic")
self.in_features = in_features
self.out_features = out_features
if bias:
bias = torch.zeros(self.out_features, dtype=torch.float)
else:
bias = None
qweight = torch._empty_affine_quantized([out_features, in_features],
scale=1, zero_point=0, dtype=torch.qint8)
self._packed_params = linear.LinearPackedParams(row_block_size=row_block_size,
col_block_size=col_block_size,
dtype=dtype)
self._packed_params.set_weight_bias(qweight, bias, row_block_size, col_block_size)
def _get_name(self):
return 'SparseQuantizedDynamicLinear'
def extra_repr(self):
return 'in_features={}, out_features={}, qscheme={}'.format(
self.in_features, self.out_features, self.weight().qscheme()
)
def __repr__(self):
return hide_packed_params_repr(self, linear.LinearPackedParams)
def forward(self, x: torch.Tensor) -> torch.Tensor:
return torch.ops.sparse.qlinear_dynamic(x, self._packed_params._packed_params)
def _save_to_state_dict(self, destination, prefix, keep_vars):
super()._save_to_state_dict(destination, prefix, keep_vars)
destination[prefix + 'op_type'] = self._op_type
def _load_from_state_dict(self, state_dict, prefix, local_metadata, strict,
missing_keys, unexpected_keys, error_msgs):
op_type = int(state_dict[prefix + 'op_type'])
assert op_type == 'sparse', \
"Cannot load from op_type [{}], expecting [{}]".format(op_type, self._op_type)
state_dict.pop(prefix + 'op_type')
version = local_metadata.get('version', None)
assert version <= self._version
# Is this code valid? In old quantization it seemed to be used to load
# older model
weight = state_dict.pop(prefix + 'weight')
bias = state_dict.pop(prefix + 'bias')
state_dict.update({prefix + '_packed_params.weight': weight,
prefix + '_packed_params.bias': bias})
super()._load_from_state_dict(
state_dict, prefix, local_metadata, False,
missing_keys, unexpected_keys, error_msgs)
def _weight_bias(self):
return self._packed_params._weight_bias()
def weight(self):
return self._weight_bias()[0]
def bias(self):
return self._weight_bias()[1]
def set_weight_bias(self, w: torch.Tensor, b: Optional[torch.Tensor],
row_block_size: Optional[int], col_block_size: Optional[int]) -> None:
assert row_block_size is not None and col_block_size is not None
self.out_features = w.shape[0]
self.in_features = w.shape[1]
self._packed_params.set_weight_bias(w, b, row_block_size, col_block_size)
@classmethod
def from_float(cls, mod):
r"""Create a quantized sparse dynamic module from a float module.
We only care about the convert at this stage, no need for observers just yet.
"""
assert type(mod) == cls._FLOAT_MODULE, ' nnq.' + cls.__name__ + '.from_float only works for ' + \
cls._FLOAT_MODULE.__name__
# TODO: Need to add options to qconfig to avoid the calibration.
# TODO: Add calibration for the sparsity
assert hasattr(mod, 'qconfig'), 'Input float module must have qconfig defined'
if type(mod) == nni.LinearReLU:
mod = mod[0]
if mod.qconfig is not None and mod.qconfig.weight is not None:
weight_observer = mod.qconfig.weight()
else:
# We have the circular import issues if we import the qconfig in the beginning of this file:
# https://github.com/pytorch/pytorch/pull/24231. The current workaround is to postpone the
# import until we need it.
from torch.ao.quantization.qconfig import default_dynamic_qconfig
weight_observer = default_dynamic_qconfig.weight()
# It is important to multiply by the mask BEFORE calling the `weight_observer`
# TODO (zaf): Mask might not be part of the qconfig (T83295194)
weight = mod.weight
if getattr(mod.qconfig, 'mask', False):
weight = mod.qconfig.mask * mod.weight
weight_observer(weight)
dtype = weight_observer.dtype
assert dtype == torch.qint8, 'Weight observer must have dtype torch.qint8'
w_sc, w_zp = weight_observer.calculate_qparams()
if isinstance(w_zp, torch.Tensor):
assert not torch.any(w_zp.bool()), "All weight zero points must map to 0"
else:
assert w_zp == 0, 'Weight zero point must map to 0'
qweight = _quantize_weight(weight.float(), weight_observer)
row_block_size, col_block_size = LinearBlockSparsePattern.block_size()
qlinear = cls(mod.in_features,
mod.out_features,
row_block_size,
col_block_size,
dtype=dtype)
qlinear.set_weight_bias(qweight, mod.bias, row_block_size, col_block_size)
return qlinear
|