ColossalAI/colossalai/tensor/_ops/linear.py

51 lines
1.8 KiB
Python

import torch
from colossalai.tensor.op_wrapper import colo_op_impl
from colossalai.tensor.colo_tensor import ColoTensor
from colossalai.context import ParallelMode
from colossalai.nn.layer.parallel_1d._utils import split_forward_gather_backward, reduce_input
from packaging import version
@colo_op_impl(torch.nn.functional.linear)
def colo_linear(types, args, kwargs, pg):
"""Handles ``__torch_function__`` dispatch for ``torch.nn.functional.linear``.
This method computes a linear.
"""
input_tensor = args[0]
weight = args[1]
if version.parse(torch.__version__) > version.parse("1.11.0"):
if len(args) == 3:
bias = args[2]
else:
bias = None
else:
bias = kwargs.get('bias', None)
if isinstance(bias, ColoTensor):
bias = bias.torch_tensor()
# Add communication logic before and after linear call.
if isinstance(weight, ColoTensor):
if weight.shard_spec == None:
return torch.nn.functional.linear(input_tensor, weight.torch_tensor(), bias)
elif weight.shard_spec == '1Drow':
"""
Input:S[1] x Weight:S[0] = Output:P
All-Reduce(Output) + bias = res
"""
# Input:S[1]
input_per_partition = split_forward_gather_backward(input_tensor, ParallelMode.PARALLEL_1D, dim=-1)
# Output:P
partial_output = torch.nn.functional.linear(input_per_partition, weight.torch_tensor())
# Reduce(Output)
output = reduce_input(partial_output, ParallelMode.PARALLEL_1D)
# Bias
if bias is not None:
output = output + bias
return output
else:
raise NotImplementedError
else:
return torch.nn.functional.linear(input_tensor, weight, bias)