ColossalAI/colossalai/nn/_ops/linear.py

94 lines
4.1 KiB
Python

import torch.nn.functional as F
from typing import Optional
from ._utils import GeneralTensor, convert_to_colo_tensor
from colossalai.tensor.op_wrapper import colo_op_impl
from ._utils import reduce_input, reduce_grad
from colossalai.tensor import ComputePattern, ComputeSpec, ColoTensor, ShardSpec, ReplicaSpec, ColoTensorSpec
def colo_linear_1drow(input_tensor: ColoTensor, weight: ColoTensor, bias: Optional[ColoTensor]) -> 'ColoTensor':
# Input:S[1] x Weight:S[0] = Output:P
# All-Reduce(Output) + bias = res
# Input:S[1]
pg = weight.get_process_group()
input_tensor = input_tensor.redistribute(ShardSpec([-1], [weight.get_tp_world_size()]), pg)
# Output:P
partial_output = F.linear(input_tensor, weight)
# Reduce(Output)
output = reduce_input(partial_output, pg)
# Bias
if bias is not None:
assert not bias.has_compute_spec(), 'Invalid bias spec for 1Drow Linear op'
output = output + bias
output = ColoTensor.from_torch_tensor(output, spec=ColoTensorSpec(pg, ReplicaSpec()))
return output
def colo_linear_1dcol(input_tensor: ColoTensor, weight: ColoTensor, bias: Optional[ColoTensor]) -> 'ColoTensor':
# Input:B x Weight:S[1] + Bias:S[1] = Output:S[1]
# All-Gather(Output)
# Input:B
compute_spec = weight.compute_spec
input_tensor = input_tensor.redistribute(ReplicaSpec())
input_parallel = reduce_grad(input_tensor, weight.get_process_group())
output_parallel = F.linear(input_parallel, weight, bias)
output = ColoTensor.from_torch_tensor(output_parallel,
spec=ColoTensorSpec(weight.get_process_group(),
ShardSpec([-1], [weight.get_tp_world_size()]),
ComputeSpec(ComputePattern.TP1D)))
if compute_spec.output_replicate:
return output.to_replicate()
else:
return output
def colo_linear_1d(mode: str, input_tensor: ColoTensor, weight: ColoTensor, bias: Optional[ColoTensor]) -> 'ColoTensor':
assert mode in ('row', 'col')
funcs = {'row': colo_linear_1drow, 'col': colo_linear_1dcol}
return funcs[mode](input_tensor, weight, bias)
# @register_colo_graph(input_pos=[1], param_pos=[2, 3])
def colo_linear_imp(input_tensor: GeneralTensor,
weight: GeneralTensor,
bias: Optional[GeneralTensor] = None) -> 'ColoTensor':
"""Handles ``__torch_function__`` dispatch for ``torch.nn.functional.linear``.
This method computes a linear.
"""
assert isinstance(weight, ColoTensor)
pg = weight.get_process_group()
assert pg
input_tensor = convert_to_colo_tensor(input_tensor, pg)
bias = convert_to_colo_tensor(bias, pg)
# input_tensor, weight, bias = tuple(map(convert_to_colo_tensor, (input_tensor, weight, bias)))
# Add communication logic before and after linear call.
ret_tensor = None
if not weight.has_compute_spec(): # No Model Parallel Applied
assert weight.is_replicate(), 'Invalid weight spec for native Linear op'
assert bias is None or bias.is_replicate(), 'Invalid bias spec for native Linear op'
ret_tensor = ColoTensor.from_torch_tensor(F.linear(input_tensor, weight, bias), spec=ColoTensorSpec(pg))
elif weight.has_compute_pattern(ComputePattern.TP1D): # Single Model Parallel Applied
if weight.is_shard_1dcol() and (bias is None or bias.is_replicate()):
mode = 'row'
elif weight.is_shard_1drow() and (bias is None or bias.is_shard_1drow() or bias.is_shard_1dcol()):
mode = 'col'
else:
raise RuntimeError(f"the weight or bias tensor spec is not valid, weight {weight}, bias {bias}")
ret_tensor = colo_linear_1d(mode, input_tensor, weight, bias)
else:
raise NotImplementedError
return ret_tensor
@colo_op_impl(F.linear)
def colo_linear(input_tensor: GeneralTensor,
weight: GeneralTensor,
bias: Optional[GeneralTensor] = None) -> 'ColoTensor':
return colo_linear_imp(input_tensor, weight, bias)