Files
vllm-ascend/vllm_ascend/ops/linear_op.py
anon189Ty 07e39620ea [Feat] Unquantized Linear to nz and control all nz-cast (#3356)
### What this PR does / why we need it?
Currently, when executing to the Linear layer of models in vLLM-Ascend,
the weights format is ND in unquantized case and skipped ascend case.
This PR supplements the execution logic for Linear layer. We use a new
global variable: VLLM_ASCEND_ENABLE_NZ. When VLLM_ASCEND_ENABLE_NZ=1 and
CANN version is 8.3, the weights of the Linear layer will be converted
to FRACTAL_NZ, in both unquantized case and skipped ascend case. We also
use VLLM_ASCEND_ENABLE_NZ to control the existing NZ conversion, such as
w8a8-quantized case.

### Does this PR introduce _any_ user-facing change?
Add a new global variable VLLM_ASCEND_ENABLE_NZ. If you want to use NZ
format, you should set VLLM_ASCEND_ENABLE_NZ=1.

### How was this patch tested?

- vLLM version: v0.11.0rc3
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.0

Signed-off-by: anon189Ty <Stari_Falcon@outlook.com>
2025-10-14 17:39:26 +08:00

445 lines
16 KiB
Python

# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
# This file is a part of the vllm-ascend project.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
This file extends the functionality of linear operations by encapsulating custom
communication groups and forward functions into classes (linear ops).
Current class inheritance structure:
CustomLinearOp
├── CustomColumnParallelOp
│ ├── MLPColumnParallelOp
│ ├── SequenceColumnParallelOp
└── CustomRowParallelOp
│ ├── MLPRowParallelOp
│ ├── OProjRowParallelOp
│ ├── MatmulAllreduceRowParallelOp
│ └── SequenceRowParallelOp
└── CustomReplicatedOp
How to extend a new linear op? Taking column parallel op as an example:
1. Inherit from CustomColumnParallelOp and create a new class MyColumnParallelOp
2. [Optional] The default communication group is the TP group. If a custom communication group is needed, override the comm_group method
3. Override the apply method according to requirements, which will replace the original linear.forward
4. Add selection logic for MyColumnParallelOp in the get_column_parallel_op method, typically based on prefix and configuration judgments
Row parallel op follows a similar approach - inherit from RowColumnParallelOp and register the new class in get_row_parallel_op.
"""
from typing import Optional, Union
import torch
import torch.distributed as dist
import torch_npu
from torch.distributed import ProcessGroup
from torch.nn.parameter import Parameter
from vllm.distributed import split_tensor_along_last_dim
from vllm.distributed.parallel_state import get_tp_group
from vllm_ascend.distributed.parallel_state import (get_mlp_tp_group,
get_otp_group)
from vllm_ascend.utils import (dense_optim_enable, enable_sp,
matmul_allreduce_enable, mlp_tp_enable,
oproj_tp_enable)
class CustomLinearOp:
def __init__(self, layer):
self.layer = layer
self.bias = None
self.skip_bias_add = None
self.return_bias = None
self.quant_method = None
# Custom communication group, while determining weight sharding
@property
def comm_group(self):
return get_tp_group()
@property
def tp_rank(self):
return self.comm_group.rank_in_group
@property
def tp_size(self):
return self.comm_group.world_size
# Update the attributes required by apply(), obtaining them from the layer.
# Call this after the layer completes its initialization, specifically at the end of layer.init().
def update_attrs(self):
if hasattr(self.layer, "bias"):
self.bias = self.layer.bias
self.skip_bias_add = self.layer.skip_bias_add
self.return_bias = self.layer.return_bias
self.quant_method = self.layer.quant_method
self.prefix = self.layer.prefix
def apply_impl(self, input_):
raise NotImplementedError
# Replace layer.forward to customize the layer computation process.
def apply(self, input_):
output, output_bias = self.apply_impl(input_)
if not self.return_bias:
return output
return output, output_bias
class CustomColumnParallelOp(CustomLinearOp):
def __init__(self, layer):
super().__init__(layer)
self.gather_output = None
def update_attrs(self):
super().update_attrs()
self.gather_output = self.layer.gather_output
class CustomRowParallelOp(CustomLinearOp):
def __init__(self, layer):
super().__init__(layer)
self.reduce_results = None
self.input_is_parallel = None
self.input_size_per_partition = None
def update_attrs(self):
super().update_attrs()
self.input_is_parallel = self.layer.input_is_parallel
self.reduce_results = self.layer.reduce_results
self.input_size_per_partition = self.layer.input_size_per_partition
def apply(self, input_):
output, output_bias = self.apply_impl(input_)
if dense_optim_enable():
torch.ops.vllm.maybe_prefetch_mlp_gate_up_proj(output, self.prefix)
if not self.return_bias:
return output
return output, output_bias
class CustomReplicatedOp(CustomLinearOp):
def apply_impl(self, input_):
bias = self.bias if not self.skip_bias_add else None
assert self.quant_method is not None
output = self.quant_method.apply(self.layer, input_, bias)
output_bias = self.bias if self.skip_bias_add else None
return output, output_bias
class MLPColumnParallelOp(CustomColumnParallelOp):
def __init__(self, layer):
super().__init__(layer)
@property
def comm_group(self):
return get_mlp_tp_group()
def apply_impl(
self,
input_: torch.Tensor,
) -> Union[torch.Tensor, tuple[torch.Tensor, Optional[Parameter]]]:
bias = self.bias if not self.skip_bias_add else None
# Matrix multiply.
assert self.quant_method is not None
input_parallel = self.comm_group.all_gather(input_, 0)
output = self.quant_method.apply(self.layer, input_parallel, bias)
output_bias = self.bias if self.skip_bias_add else None
return output, output_bias
class MLPRowParallelOp(CustomRowParallelOp):
def __init__(self, layer):
super().__init__(layer)
@property
def comm_group(self):
return get_mlp_tp_group()
def apply_impl(
self, input_: torch.Tensor
) -> Union[torch.Tensor, tuple[torch.Tensor, Optional[Parameter]]]:
if self.input_is_parallel:
input_parallel = input_
else:
splitted_input = split_tensor_along_last_dim(
input_, num_partitions=self.tp_size)
input_parallel = splitted_input[self.tp_rank].contiguous()
assert self.quant_method is not None
bias_ = None if (self.tp_rank > 0
or self.skip_bias_add) else self.layer.bias
output_parallel = self.quant_method.apply(self.layer,
input_parallel,
bias=bias_)
output = self.comm_group.reduce_scatter(output_parallel, 0)
output_bias = self.bias if self.skip_bias_add else None
return output, output_bias
class OProjRowParallelOp(CustomRowParallelOp):
def __init__(self, layer):
super().__init__(layer)
@property
def comm_group(self):
return get_otp_group()
def apply_impl(
self,
input_: torch.Tensor,
) -> Union[torch.Tensor, tuple[torch.Tensor, Optional[Parameter]]]:
if self.input_is_parallel:
input_parallel = input_
else:
splitted_input = split_tensor_along_last_dim(
input_, num_partitions=self.tp_size)
input_parallel = splitted_input[self.tp_rank].contiguous()
# Prepare tensors for all-to-all communication
local_batch_size = input_parallel.size(0)
chunk_size = self.input_size_per_partition
total_batch_size = local_batch_size * self.tp_size
# Reshape tensor for efficient cross-device transfer:
# [batch, dim] -> [tp_size, batch, chunk] -> flattened
send_buf = (input_parallel.reshape(-1,
self.tp_size, chunk_size).transpose(
0, 1).contiguous().view(-1))
# Create receive buffer
recv_buf = torch.empty(total_batch_size * chunk_size,
dtype=input_parallel.dtype,
device=input_parallel.device)
# Perform all-to-all communication
dist.all_to_all_single(recv_buf,
send_buf,
group=self.comm_group.device_group)
input_parallel = recv_buf.view(total_batch_size, chunk_size)
# Only fuse bias add for rank 0 to avoid duplicate bias addition in TP>1
bias_ = None if (self.tp_rank > 0 or self.skip_bias_add) else self.bias
assert self.quant_method is not None
output_parallel = self.quant_method.apply(self.layer,
input_parallel,
bias=bias_)
# otp-specific: Combine partial results across devices
output = self.comm_group.reduce_scatter(output_parallel, dim=0)
output = output.view(input_.shape[0], self.layer.output_size)
# Handle bias return based on configuration
output_bias = self.bias if self.skip_bias_add else None
return output, output_bias
def update_attrs(self):
super().update_attrs()
self.input_is_parallel = self.layer.input_is_parallel
self.input_size_per_partition = self.layer.input_size_per_partition
class MatmulAllreduceRowParallelOp(CustomRowParallelOp):
_HCOMM_INFO = None
def __init__(self, layer):
super().__init__(layer)
self.hcomm_info = self.get_hcomm_info(self.comm_group.device_group)
def apply_impl(
self, input_: torch.Tensor
) -> Union[torch.Tensor, tuple[torch.Tensor, Optional[Parameter]]]:
if self.input_is_parallel:
input_parallel = input_
else:
splitted_input = split_tensor_along_last_dim(
input_, num_partitions=self.tp_size)
input_parallel = splitted_input[self.tp_rank].contiguous()
"""Calculate the output tensor of forward by considering
fusing communication and computation."""
bias_ = None if (self.tp_rank > 0 or self.skip_bias_add) else self.bias
if self.reduce_results and self.tp_size > 1:
output = torch_npu.npu_mm_all_reduce_base(input_parallel,
self.weight_t,
self.hcomm_info,
bias=bias_)
else:
assert self.quant_method is not None
output = self.quant_method.apply(self.layer,
input_parallel,
bias=bias_)
output_bias = self.bias if self.skip_bias_add else None
return output, output_bias
@classmethod
def get_hcomm_info(cls, group: ProcessGroup) -> str:
"""Get the HCCL communication information for the given group."""
if cls._HCOMM_INFO is not None:
return cls._HCOMM_INFO
rank = torch.distributed.get_rank(group)
if torch.__version__ > "2.0":
global_rank = torch.distributed.get_global_rank(group, rank)
cls._HCOMM_INFO = group._get_backend(
torch.device("npu")).get_hccl_comm_name(global_rank)
else:
cls._HCOMM_INFO = group.get_hccl_comm_name(rank)
return cls._HCOMM_INFO
def update_attrs(self):
super().update_attrs()
self.weight_t = self.layer.weight.t()
class SequenceColumnParallelOp(CustomColumnParallelOp):
def apply_impl(
self, input_: torch.Tensor
) -> Union[torch.Tensor, tuple[torch.Tensor, Optional[Parameter]]]:
"""Linear layer with column parallelism.
Implemented multiple optimization projects for dense models, such as FlashComm and
communication-computation fusion.
"""
bias = self.bias if not self.skip_bias_add else None
# Matrix multiply.
assert self.quant_method is not None
input_ = torch.ops.vllm.maybe_all_gather_and_maybe_unpad(input_, True)
output_parallel = self.quant_method.apply(self.layer, input_, bias)
if self.gather_output:
# All-gather across the partitions.
output = self.comm_group.all_gather(output_parallel)
else:
output = output_parallel
output_bias = self.bias if self.skip_bias_add else None
return output, output_bias
class SequenceRowParallelOp(CustomRowParallelOp):
def apply_impl(
self, input_: torch.Tensor
) -> Union[torch.Tensor, tuple[torch.Tensor, Optional[Parameter]]]:
"""Linear layer with column parallelism.
Implemented multiple optimization projects for dense models, such as FlashComm and
communication-computation fusion.
"""
if self.input_is_parallel:
input_parallel = input_
else:
splitted_input = split_tensor_along_last_dim(
input_, num_partitions=self.tp_size)
input_parallel = splitted_input[self.tp_rank].contiguous()
assert self.quant_method is not None
bias_ = None if (self.tp_rank > 0 or self.skip_bias_add) else self.bias
if self.tp_size == 1 or not self.reduce_results:
output = self.quant_method.apply(self.layer,
input_parallel,
bias=bias_)
else:
output_parallel = self.quant_method.apply(self.layer,
input_parallel,
bias=bias_)
output = torch.ops.vllm.maybe_pad_and_reduce(output_parallel)
output_bias = self.bias if self.skip_bias_add else None
return output, output_bias
def update_attrs(self):
super().update_attrs()
self.input_is_parallel = self.layer.input_is_parallel
self.reduce_results = self.layer.reduce_results
def _get_column_parallel_op(
prefix, layer
) -> Optional[Union[MLPColumnParallelOp, SequenceColumnParallelOp]]:
if mlp_tp_enable() and "gate_up_proj" in prefix:
return MLPColumnParallelOp(layer)
if enable_sp():
if "shared_expert" in prefix:
return None
if "gate_up_proj" in prefix:
return SequenceColumnParallelOp(layer)
if "in_proj" in prefix:
return SequenceColumnParallelOp(layer)
if "qkv_proj" in prefix or "conv1d" in prefix:
return SequenceColumnParallelOp(layer)
return None
def _get_row_parallel_op(
prefix, layer
) -> Optional[Union[MLPRowParallelOp, OProjRowParallelOp,
MatmulAllreduceRowParallelOp, SequenceRowParallelOp]]:
if "down_proj" in prefix and mlp_tp_enable():
return MLPRowParallelOp(layer)
if "o_proj" in prefix and oproj_tp_enable():
return OProjRowParallelOp(layer)
if matmul_allreduce_enable():
return MatmulAllreduceRowParallelOp(layer)
if enable_sp():
if "shared_expert" in prefix:
return None
if "o_proj" in prefix or "out_proj" in prefix or "down_proj" in prefix:
return SequenceRowParallelOp(layer)
return None
def get_parallel_op(disable_tp, prefix, layer, direct):
if disable_tp:
return None, 0, 1
custom_op: Optional[Union[MLPColumnParallelOp, SequenceColumnParallelOp,
MLPRowParallelOp, OProjRowParallelOp,
MatmulAllreduceRowParallelOp,
SequenceRowParallelOp]] = None
if direct == "row":
custom_op = _get_row_parallel_op(prefix, layer)
if direct == "column":
custom_op = _get_column_parallel_op(prefix, layer)
if custom_op is not None:
return custom_op, custom_op.tp_rank, custom_op.tp_size
return None, get_tp_group().rank_in_group, get_tp_group().world_size
def get_replicated_op(disable_tp, prefix,
layer) -> Optional[Union[CustomReplicatedOp]]:
if disable_tp:
return None
return CustomReplicatedOp(layer)