Files
xc-llm-ascend/vllm_ascend/quantization/quant_config.py
Anion 5f8b1699ae [Feat][quantization] Support new version w4a8 dynamic quantization for Linear layers (#3311)
### What this PR does / why we need it?
**Problem Description:**

The existing implementation for the w4a8-dynamic linear method only
supports the old quantization format from msmodelslim. When attempting
to load models quantized with the new version, vLLM encounters errors
due to mismatched tensor shapes and unprocessed quantization parameters.

Relavant issues: 
- https://github.com/vllm-project/vllm-ascend/issues/3192
- https://github.com/vllm-project/vllm-ascend/issues/3152

**Proposed Changes:**
1. Add support for w4a8 dynamic(new format) in
AscendW4A8DynamicLinearMethod and TorchairAscendW4A8DynamicLinearMethod
2. Add unit tests and e2e tests for w4a8 dynamic new and old format
models
<details>
<summary><b>details</b></summary>

1.  **Support for new w4a8-dynamic format:**
* Detects quantization format by reading the "version" field in
quant_description to ensure backward compatibility.
* Handles the new pre-packed weight format (`2x int4` in an `int8`),
which has a halved dimension. It tells the vLLM loader how to unpack it
using `_packed_dim` and `_packed_factor`.
* Supports the new `scale_bias` parameter, setting its shape based on
the layer type, as required by msmodelslim. For api consistency and
future use, the `layer_type` parameter was also added to other
quantization methods.
* Updates the weight processing logic: new format weights are handled
with `.view(torch.int32)` since they're pre-packed, while old ones are
processed with `npu_convert_weight_to_int4pack`.

2.  **New unit and E2E tests:**
* Added unit tests that verify the logic for both the old and new
formats.
* Split the distributed E2E test to confirm that both old and new format
models work correctly.

</details>
Theoretically, these changes will provide support for all common new
version w4a8(dynamic) models from msmodelslim.

### Does this PR introduce _any_ user-facing change?
no

### How was this patch tested?
I implement relevant unit tests and e2e tests and test the changes with
following commands:
```bash
# unit tests
python -m pytest tests/ut/quantization/test_w4a8_dynamic.py tests/ut/torchair/quantization/test_torchair_w4a8_dynamic.py -v

# e2e tests
pytest tests/e2e/singlecard/test_quantization.py -v -s

pytest tests/e2e/multicard/test_offline_inference_distributed.py::test_models_distributed_Qwen3_W4A8DYNAMIC_new_version -v -s
pytest tests/e2e/multicard/test_offline_inference_distributed.py::test_models_distributed_Qwen3_W4A8DYNAMIC_old_version -v -s
pytest tests/e2e/multicard/test_offline_inference_distributed.py::test_models_distributed_DeepSeek_W4A8DYNAMIC -v -s

```

I also tested Hunyuan-1.8B-Instruct quantized with the new w4a8-dynamic
format:
```
vllm serve ./models/Hunyuan-1.8B-Instruct-quantized --gpu-memory-utilization 0.96 --quantization ascend --max-model-len 9600 --seed 0 --max-num-batched-tokens 16384 
```

All tests mentioned passed locally.

**NOTE: I use quantization model from my own repo in
test_offline_inference_distributed.py**. Here is the description:
[Anionex/Qwen3-1.7B-W4A8-V1](https://modelscope.cn/models/Anionex/Qwen3-1.7B-W4A8-V1/summary)
(including quantization steps).This should be replaced by a model in
vllm-ascend ci modelscope repo.

Thanks for reading!


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

---------

Signed-off-by: Anionex <1005128408@qq.com>
2025-10-21 20:18:39 +08:00

475 lines
19 KiB
Python

#
# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
# Copyright 2023 The vLLM team.
#
# 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 is a part of the vllm-ascend project.
#
from types import MappingProxyType
from typing import Any, Callable, Dict, List, Mapping, Optional
import torch
from vllm.config import get_current_vllm_config
from vllm.distributed import get_tensor_model_parallel_rank
from vllm.model_executor.layers.fused_moe import (FusedMoE, FusedMoEMethodBase,
FusedMoeWeightScaleSupported)
from vllm.model_executor.layers.linear import (LinearBase, LinearMethodBase,
RowParallelLinear)
from vllm.model_executor.layers.quantization import \
register_quantization_config
from vllm.model_executor.layers.quantization.base_config import (
QuantizationConfig, QuantizeMethodBase)
from vllm.model_executor.layers.quantization.kv_cache import BaseKVCacheMethod
from vllm.model_executor.layers.vocab_parallel_embedding import (
UnquantizedEmbeddingMethod, VocabParallelEmbedding)
from vllm.model_executor.parameter import PerTensorScaleParameter
from vllm.model_executor.utils import set_weight_attrs
from vllm_ascend.distributed.parallel_state import (get_mlp_tp_group,
get_otp_group)
from vllm_ascend.ops.common_fused_moe import AscendUnquantizedFusedMoEMethod
from vllm_ascend.ops.linear import AscendUnquantizedLinearMethod
from vllm_ascend.utils import (ASCEND_QUANTIZATION_METHOD, mlp_tp_enable,
oproj_tp_enable)
from .utils import get_quant_method
@register_quantization_config(ASCEND_QUANTIZATION_METHOD)
class AscendQuantConfig(QuantizationConfig):
"""Config class for Ascend
This class is a general class that parse quantization configs
that are supported on ascend hardware.
"""
def __init__(self, quant_config: Dict[str, Any]):
super().__init__()
self.quant_description = quant_config
# TODO(whx): remove this adaptation after adding "shared_head"
# to prefix of DeepSeekShareHead in vLLM.
extra_quant_dict = {}
for k in self.quant_description.keys():
if "shared_head" in k:
new_k = k.replace(".shared_head.", ".")
extra_quant_dict[new_k] = self.quant_description[k]
self.quant_description.update(extra_quant_dict)
def __repr__(self) -> str:
return "AscendQuantConfig:\n" + super().__repr__()
@classmethod
def get_name(cls) -> str:
return ASCEND_QUANTIZATION_METHOD
@classmethod
def get_supported_act_dtypes(cls) -> List[torch.dtype]:
return [torch.int8, torch.float16, torch.bfloat16]
@classmethod
def get_min_capability(cls) -> int:
raise NotImplementedError(
"Ascend hardware dose not support \"get_min_capability\" feature.")
@classmethod
def get_config_filenames(cls) -> List[str]:
return ["quant_model_description.json"]
@classmethod
def from_config(cls, config: Dict[str, Any]) -> "AscendQuantConfig":
return cls(config)
@classmethod
def override_quantization_method(cls, hf_quant_cfg,
user_quant) -> Optional[str]:
if torch.npu.is_available():
return ASCEND_QUANTIZATION_METHOD
return None
def get_quant_method(self, layer: torch.nn.Module,
prefix: str) -> Optional["QuantizeMethodBase"]:
vllm_config = get_current_vllm_config()
model_type = vllm_config.model_config.hf_config.model_type
if model_type in packed_modules_model_mapping:
self.packed_modules_mapping = packed_modules_model_mapping[
model_type]
from vllm.attention.layer import Attention
if prefix.startswith("language_model"):
prefix = prefix.split('.', 1)[-1]
if isinstance(layer, LinearBase):
if self.is_layer_skipped_ascend(prefix,
self.packed_modules_mapping):
return AscendUnquantizedLinearMethod()
return AscendLinearMethod(self, prefix,
self.packed_modules_mapping)
elif isinstance(layer, Attention) and \
'fa_quant_type' in self.quant_description.keys() and \
self.quant_description['fa_quant_type'] is not None:
return AscendKVCacheMethod(self, prefix)
elif isinstance(layer, Attention) and self.quant_description.get(
'kv_quant_type') == 'C8':
return AscendKVCacheMethod(self, prefix)
elif isinstance(layer, FusedMoE):
if self.is_layer_skipped_ascend(prefix,
self.packed_modules_mapping):
return AscendUnquantizedFusedMoEMethod(layer.moe_config)
return AscendFusedMoEMethod(self, prefix,
self.packed_modules_mapping)
elif isinstance(layer, VocabParallelEmbedding):
if self.is_layer_skipped_ascend(prefix,
self.packed_modules_mapping):
return UnquantizedEmbeddingMethod()
return AscendEmbeddingMethod(self, prefix,
self.packed_modules_mapping)
return None
def is_layer_skipped_ascend(
self,
prefix: str,
fused_mapping: Mapping[str, List[str]] = MappingProxyType({})):
# adapted from vllm.model_executor.layers.quantization.utils.quant_utils.is_layer_skipped
proj_name = prefix.split(".")[-1]
if proj_name in fused_mapping:
shard_prefixes = [
prefix.replace(proj_name, shard_proj_name)
for shard_proj_name in fused_mapping[proj_name]
]
is_skipped = None
for shard_prefix in shard_prefixes:
is_shard_skipped = self.quant_description[shard_prefix +
'.weight'] == "FLOAT"
if is_skipped is None:
is_skipped = is_shard_skipped
elif is_shard_skipped != is_skipped:
raise ValueError(
f"Detected some but not all shards of {prefix} "
"are quantized. All shards of fused layers "
"to have the same precision.")
else:
is_skipped = self.quant_description[prefix + '.weight'] == "FLOAT"
assert is_skipped is not None
return is_skipped
def get_scaled_act_names(self) -> List[str]:
return []
packed_modules_model_mapping = {
"qwen3_moe": {
"qkv_proj": [
"q_proj",
"k_proj",
"v_proj",
],
"gate_up_proj": [
"gate_proj",
"up_proj",
],
"experts":
["experts.0.gate_proj", "experts.0.up_proj", "experts.0.down_proj"],
},
"deepseek_v2": {
"gate_up_proj": ["gate_proj", "up_proj"],
"experts":
["experts.0.gate_proj", "experts.0.up_proj", "experts.0.down_proj"],
"fused_qkv_a_proj": ["q_a_proj", "kv_a_proj_with_mqa"]
},
"deepseek_v3": {
"gate_up_proj": ["gate_proj", "up_proj"],
"experts":
["experts.0.gate_proj", "experts.0.up_proj", "experts.0.down_proj"],
"fused_qkv_a_proj": ["q_a_proj", "kv_a_proj_with_mqa"]
},
"deepseek_v32": {
"gate_up_proj": ["gate_proj", "up_proj"],
"experts":
["experts.0.gate_proj", "experts.0.up_proj", "experts.0.down_proj"]
},
# NOTE 1.The quantized MTP layer of deepseek on the NPU is not quantized;
# NOTE 2.The description file generated by the current msmodelslim tool does not have
# MTP layer info. Please manually add it and set the value to FLOAT.
"deepseek_mtp": {
"gate_up_proj": ["gate_proj", "up_proj"],
"experts":
["experts.0.gate_proj", "experts.0.up_proj", "experts.0.down_proj"]
},
"qwen3_next": {
"qkv_proj": [
"q_proj",
"k_proj",
"v_proj",
],
"gate_up_proj": ["gate_proj", "up_proj"],
"in_proj": ["in_proj_qkvz", "in_proj_ba"],
},
"qwen2_5_vl": {
"qkv_proj": [
"q_proj",
"k_proj",
"v_proj",
],
"gate_up_proj": [
"gate_proj",
"up_proj",
],
},
"glm4_moe": {
"qkv_proj": [
"q_proj",
"k_proj",
"v_proj",
],
"gate_up_proj": [
"gate_proj",
"up_proj",
],
"experts":
["experts.0.gate_proj", "experts.0.up_proj", "experts.0.down_proj"]
},
}
class AscendLinearMethod(LinearMethodBase):
"""Linear method for Ascend quantization.
Args:
quant_config: The Ascend quantization config.
"""
def __init__(self, quant_config: AscendQuantConfig, prefix: str,
packed_modules_mapping: Dict[str, Any]) -> None:
self.quant_method = get_quant_method(quant_config.quant_description,
prefix, "linear",
packed_modules_mapping)
def create_weights(
self,
layer: torch.nn.Module,
input_size_per_partition: int,
output_partition_sizes: List[int],
input_size: int,
output_size: int,
params_dtype: torch.dtype,
**extra_weight_attrs,
) -> None:
output_size_per_partition = sum(output_partition_sizes)
weight_loader = extra_weight_attrs.get("weight_loader")
weight_dict = self.quant_method.get_weight(input_size_per_partition,
output_size_per_partition,
params_dtype)
# Extract packing information (if present)
packed_dim = weight_dict.pop("_packed_dim", None)
packed_factor = weight_dict.pop("_packed_factor", None)
for weight_name, weight_param in weight_dict.items():
param = torch.nn.Parameter(weight_param, requires_grad=False)
set_weight_attrs(param, {"input_dim": 1, "output_dim": 0})
# Set packing attributes if the weight is packed
if packed_dim is not None and packed_factor is not None:
set_weight_attrs(param, {
"packed_dim": packed_dim,
"packed_factor": packed_factor
})
layer.register_parameter(weight_name, param)
set_weight_attrs(param, extra_weight_attrs)
pertensor_dict = self.quant_method.get_pertensor_param(params_dtype)
for pertensor_name, pertensor_param in pertensor_dict.items():
param = PerTensorScaleParameter(data=pertensor_param,
weight_loader=weight_loader)
# disable warning
param.ignore_warning = True
layer.register_parameter(pertensor_name, param)
param.weight_loader = extra_weight_attrs.get("weight_loader")
perchannel_dict = self.quant_method.get_perchannel_param(
output_size_per_partition, params_dtype)
for perchannel_name, perchannel_param in perchannel_dict.items():
param = torch.nn.Parameter(perchannel_param, requires_grad=False)
set_weight_attrs(param, {"output_dim": 0})
layer.register_parameter(perchannel_name, param)
set_weight_attrs(param, extra_weight_attrs)
# NOTE: In w4a8 quantization implementation,
# for down_proj and o_proj scale_bias shape is [output_size, 16],
# others are [output_size, 1]
layer_type = "row" if isinstance(layer,
RowParallelLinear) else "others"
pergroup_dict = self.quant_method.get_pergroup_param(
input_size_per_partition,
output_size_per_partition,
params_dtype,
layer_type=layer_type)
for pergroup_name, pergroup_param in pergroup_dict.items():
param = torch.nn.Parameter(pergroup_param, requires_grad=False)
set_weight_attrs(param, {"output_dim": 0})
layer.register_parameter(pergroup_name, param)
set_weight_attrs(param, extra_weight_attrs)
if "weight_scale_second" in pergroup_name or "weight_offset_second" in pergroup_name:
setattr(param, "input_dim", 1)
param.input_dim = 1
def process_weights_after_loading(self, layer: torch.nn.Module) -> None:
if hasattr(self.quant_method, "process_weights_after_loading"):
self.quant_method.process_weights_after_loading(layer)
def apply(
self,
layer: torch.nn.Module,
x: torch.Tensor,
bias: Optional[torch.Tensor] = None,
) -> torch.Tensor:
if isinstance(layer, RowParallelLinear):
if layer.prefix.find("o_proj") != -1 and oproj_tp_enable():
tp_rank = get_otp_group().rank_in_group
elif layer.prefix.find("down_proj") != -1 and mlp_tp_enable():
tp_rank = get_mlp_tp_group().rank_in_group
else:
tp_rank = get_tensor_model_parallel_rank()
else:
tp_rank = 0
return self.quant_method.apply(layer, x, bias, tp_rank)
class AscendKVCacheMethod(BaseKVCacheMethod):
"""KVCache method for Ascend quantization.
Args:
quant_config: The Ascend quantization config.
"""
def __init__(self, quant_config: AscendQuantConfig, prefix: str) -> None:
self.quant_method = get_quant_method(quant_config.quant_description,
prefix, "attention")
def create_weights(self, layer: torch.nn.Module) -> None:
# Different from linear method, there are no weight processing/slicing
# steps for attention in vllm. So the whole process of create weights
# is hidden into the specific quant method.
self.quant_method.create_weights(layer)
def process_weights_after_loading(self, layer: torch.nn.Module) -> None:
if hasattr(self.quant_method, "process_weights_after_loading"):
self.quant_method.process_weights_after_loading(layer)
def apply(self, layer: torch.nn.Module, query: torch.Tensor,
key: torch.Tensor, value: torch.Tensor, kv_cache, attn_metadata,
attn_type, scale, output) -> torch.Tensor:
return self.quant_method.apply(layer, query, key, value, kv_cache,
attn_metadata, attn_type, scale, output)
class AscendFusedMoEMethod(FusedMoEMethodBase):
"""FusedMoE method for Ascend quantization.
Args:
quant_config: The Ascend quantization config.
"""
def __init__(self, quant_config: AscendQuantConfig, prefix: str,
packed_modules_mapping: Dict[str, Any]):
self.quant_method = get_quant_method(quant_config.quant_description,
prefix, "moe",
packed_modules_mapping)
def create_weights(
self,
layer: torch.nn.Module,
num_experts: int,
hidden_size: int,
intermediate_size_per_partition: int,
params_dtype: torch.dtype,
**extra_weight_attrs,
) -> None:
weight_param = self.quant_method.get_weight(
num_experts, intermediate_size_per_partition, hidden_size,
params_dtype)
for param_key, param_value in weight_param.items():
param = torch.nn.Parameter(param_value, requires_grad=False)
layer.register_parameter(param_key, param)
set_weight_attrs(param, extra_weight_attrs)
extra_weight_attrs.update(
{"quant_method": FusedMoeWeightScaleSupported.CHANNEL.value})
per_group_param = [
"weight_scale_second", "weight_offset_second", "scale_bias"
]
dynamic_quant_param = self.quant_method.get_dynamic_quant_param(
num_experts, intermediate_size_per_partition, hidden_size,
params_dtype)
for param_key, param_value in dynamic_quant_param.items():
param = torch.nn.Parameter(param_value, requires_grad=False)
layer.register_parameter(param_key, param)
set_weight_attrs(param, extra_weight_attrs)
if any(fields in param_key for fields in per_group_param):
setattr(param, "quant_method",
FusedMoeWeightScaleSupported.GROUP.value)
def apply(
self,
layer: torch.nn.Module,
x: torch.Tensor,
router_logits: torch.Tensor,
top_k: int,
renormalize: bool,
use_grouped_topk: bool = False,
global_num_experts: int = -1,
expert_map: Optional[torch.Tensor] = None,
topk_group: Optional[int] = None,
num_expert_group: Optional[int] = None,
custom_routing_function: Optional[Callable] = None,
scoring_func: str = "softmax",
e_score_correction_bias: Optional[torch.Tensor] = None,
is_prefill: bool = True,
enable_force_load_balance: bool = False,
log2phy: torch.Tensor = None,
global_redundant_expert_num=0,
**kwargs,
) -> torch.Tensor:
return self.quant_method.apply(
layer, x, router_logits, top_k, renormalize, use_grouped_topk,
global_num_experts, expert_map, topk_group, num_expert_group,
custom_routing_function, scoring_func, e_score_correction_bias,
is_prefill, enable_force_load_balance, log2phy,
global_redundant_expert_num, **kwargs)
def process_weights_after_loading(self, layer: torch.nn.Module) -> None:
if hasattr(self.quant_method, "process_weights_after_loading"):
self.quant_method.process_weights_after_loading(layer)
def get_fused_moe_quant_config(self, layer: torch.nn.Module):
# TODO: implement this function
pass
class AscendEmbeddingMethod(AscendLinearMethod):
"""Embedding method for Ascend quantization.
Args:
quant_config: The Ascend quantization config.
"""
def __init__(self, quant_config: AscendQuantConfig, prefix: str,
packed_modules_mapping: Dict[str, Any]) -> None:
self.quant_method = get_quant_method(quant_config.quant_description,
prefix, "linear",
packed_modules_mapping)