Files
xc-llm-ascend/vllm_ascend/quantization/modelslim_config.py
Cao Yi 3953dcf784 [Feature][Quant] Auto-detect quantization format from model files (#6645)
## Summary

- Add automatic quantization format detection, eliminating the need to
manually specify `--quantization` when serving quantized models.
- The detection inspects only lightweight JSON files
(`quant_model_description.json` and `config.json`) at engine
initialization time, with no `.safetensors` reads.
- User-explicit `--quantization` flags are always respected;
auto-detection only applies when the flag is omitted.

## Details

**Detection priority:**
1. `quant_model_description.json` exists → `quantization="ascend"`
(ModelSlim)
2. `config.json` contains `"quant_method": "compressed-tensors"` →
`quantization="compressed-tensors"` (LLM-Compressor)
3. Neither → default float behavior

**Technical approach:**
Hooked into `NPUPlatform.check_and_update_config()` to run detection
after `VllmConfig.__post_init__`. Since `quant_config` is already `None`
at that point, we explicitly recreate it via
`VllmConfig._get_quantization_config()` to trigger the full quantization
initialization pipeline.

## Files Changed

| File | Description |
|------|-------------|
| `vllm_ascend/quantization/utils.py` | Added
`detect_quantization_method()` and `maybe_auto_detect_quantization()` |
| `vllm_ascend/platform.py` | Integrated auto-detection in
`check_and_update_config()` |
| `vllm_ascend/quantization/modelslim_config.py` | Improved error
handling for weight loading |
- vLLM version: v0.15.0
- vLLM main:
d7e17aaacd

---------

Signed-off-by: SlightwindSec <slightwindsec@gmail.com>
2026-02-26 10:59:25 +08:00

565 lines
22 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.
#
"""ModelSlim quantization configuration and model mappings for Ascend.
This module provides the AscendModelSlimConfig class for parsing quantization
configs generated by the ModelSlim tool, along with model-specific mappings.
"""
import glob
import json
import os
from collections.abc import Mapping
from types import MappingProxyType
from typing import Any, Optional
import torch
from vllm.config import get_current_vllm_config
from vllm.logger import init_logger
from vllm.model_executor.layers.fused_moe import FusedMoE
from vllm.model_executor.layers.linear import LinearBase
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.vocab_parallel_embedding import UnquantizedEmbeddingMethod, VocabParallelEmbedding
from vllm.model_executor.models.utils import WeightsMapper
from vllm_ascend.utils import ASCEND_QUANTIZATION_METHOD
from .methods import get_scheme_class
# The config filename that ModelSlim generates after quantizing a model.
MODELSLIM_CONFIG_FILENAME = "quant_model_description.json"
logger = init_logger(__name__)
# key: model_type
# value: orig_to_new_prefix
QUANT_MODEL_PREFIX_MAPPINGS: dict[str, dict[str, str]] = {
"qwen3_vl_moe": {
"visual.": "model.visual.",
"language_model.lm_head.": "lm_head.",
"language_model.model.": "model.language_model.",
},
"qwen3_vl_text": {
"visual.": "model.visual.",
"language_model.lm_head.": "lm_head.",
"language_model.model.": "model.language_model.",
},
"kimi_k25": {
"mm_projector.linear_1": "mm_projector.proj.0",
"mm_projector.linear_2": "mm_projector.proj.2",
},
}
# key: model_type
# value: dict of fused module name -> list of original module names
packed_modules_model_mapping: dict[str, dict[str, list[str]]] = {
"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"],
},
"pangu_ultra_moe": {
"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"],
},
"kimi_k2": {
"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"],
"fused_qkv_a_proj": ["q_a_proj", "kv_a_proj_with_mqa"],
},
"glm_moe_dsa": {
"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"],
},
# 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"],
},
"pangu_ultra_moe_mtp": {
"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"],
},
"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"],
"experts": ["experts.0.gate_proj", "experts.0.up_proj", "experts.0.down_proj"],
},
"qwen2_5_vl": {
"qkv_proj": [
"q_proj",
"k_proj",
"v_proj",
],
"gate_up_proj": [
"gate_proj",
"up_proj",
],
},
"qwen3_vl_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"],
},
"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"],
},
"glm4_moe_lite": {
"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"],
},
"longcat_flash": {
"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"],
},
"minimax_m2": {
"qkv_proj": [
"q_proj",
"k_proj",
"v_proj",
],
"experts": ["experts.0.w1", "experts.0.w2", "experts.0.w3"],
},
}
def get_packed_modules_mapping(model_type: str) -> dict[str, list[str]]:
"""Get packed modules mapping for a model type.
Args:
model_type: The model type string (e.g., "deepseek_v3").
Returns:
Dictionary mapping fused module names to their component module names.
Returns empty dict if model_type is not found.
"""
return packed_modules_model_mapping.get(model_type, {})
def get_prefix_mapping(model_type: str) -> dict[str, str]:
"""Get prefix mapping for a model type.
Args:
model_type: The model type string (e.g., "qwen3_vl_moe").
Returns:
Dictionary mapping original prefixes to new prefixes.
Returns empty dict if model_type is not found.
"""
return QUANT_MODEL_PREFIX_MAPPINGS.get(model_type, {})
def get_linear_quant_type(
quant_description: dict[str, Any], prefix: str, packed_modules_mapping: dict[str, Any]
) -> str | None:
"""Determine the quantization type for a linear layer.
Args:
quant_description: The quantization description dictionary.
prefix: The layer prefix.
packed_modules_mapping: Mapping for packed/fused modules.
Returns:
The quantization type string (e.g., "W8A8_DYNAMIC").
"""
proj_name = prefix.split(".")[-1]
if proj_name in packed_modules_mapping:
quant_type = None
shard_prefixes = [
prefix.replace(proj_name, shard_proj_name) for shard_proj_name in packed_modules_mapping[proj_name]
]
for shard_prefix in shard_prefixes:
shard_quant_type = quant_description[shard_prefix + ".weight"]
if quant_type is None:
quant_type = shard_quant_type
elif shard_quant_type != quant_type:
raise ValueError(
f"Not all shards of {prefix} are quantized with same quant type."
f"Shard {proj_name} uses {shard_quant_type}, but another shard"
f"use {quant_type}. Please check quantization config."
)
else:
quant_type = quant_description[prefix + ".weight"]
return quant_type
def get_quant_type_for_layer(
quant_description: dict[str, Any],
prefix: str,
layer_type: str,
packed_modules_mapping: dict[str, Any] | None = None,
) -> str | None:
"""Determine the quantization type for a layer.
Args:
quant_description: The quantization description dictionary.
prefix: The layer prefix.
layer_type: The type of layer ("linear", "moe", "attention").
packed_modules_mapping: Mapping for packed/fused modules.
Returns:
The quantization type string (e.g., "W8A8_DYNAMIC").
"""
if packed_modules_mapping is None:
packed_modules_mapping = dict()
# Attention
if layer_type == "attention" and "fa_quant_type" in quant_description:
return quant_description["fa_quant_type"]
# Linear / MoE
return get_linear_quant_type(quant_description, prefix, packed_modules_mapping)
def create_scheme_for_layer(
quant_description: dict[str, Any],
prefix: str,
layer_type: str,
packed_modules_mapping: dict[str, Any] | None = None,
):
"""Create a quantization scheme instance for a layer.
Args:
quant_description: The quantization description dictionary.
prefix: The layer prefix.
layer_type: The type of layer ("linear", "moe", "attention").
packed_modules_mapping: Mapping for packed/fused modules.
Returns:
An instance of the appropriate quantization scheme class.
"""
logger.info_once("Using the vLLM Ascend modelslim Quantization now!")
quant_type = get_quant_type_for_layer(quant_description, prefix, layer_type, packed_modules_mapping)
if quant_type is None:
raise ValueError(f"Could not determine quantization type for layer {prefix}.")
# Use registry to get scheme class
scheme_cls = get_scheme_class(quant_type, layer_type)
if scheme_cls is not None:
return scheme_cls()
raise NotImplementedError(f"Currently, vLLM Ascend doesn't support {quant_type} for {layer_type}.")
@register_quantization_config(ASCEND_QUANTIZATION_METHOD)
class AscendModelSlimConfig(QuantizationConfig):
"""Config class for Ascend ModelSlim quantization.
This class is a general class that parses quantization configs
that are supported on Ascend hardware, specifically for models
quantized using the ModelSlim tool.
"""
def __init__(self, quant_config: dict[str, Any] | None = None):
super().__init__()
self.quant_description = quant_config if quant_config is not None else {}
# TODO(whx): remove this adaptation after adding "shared_head"
# to prefix of DeepSeekShareHead in vLLM.
extra_quant_dict = {}
for k in self.quant_description:
if "shared_head" in k:
new_k = k.replace(".shared_head.", ".")
extra_quant_dict[new_k] = self.quant_description[k]
if "weight_packed" in k:
new_k = k.replace("weight_packed", "weight")
extra_quant_dict[new_k] = self.quant_description[k]
self.quant_description.update(extra_quant_dict)
def __repr__(self) -> str:
return "AscendModelSlimConfig:\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 empty list so that vllm's get_quant_config() skips the
# file-based lookup (which raises an unfriendly "Cannot find the
# config file for ascend" error when the model is not quantized).
# Instead, the config file is loaded in maybe_update_config(),
# which can provide a user-friendly error message.
return []
@classmethod
def from_config(cls, config: dict[str, Any]) -> "AscendModelSlimConfig":
return cls(config)
@classmethod
def override_quantization_method(cls, hf_quant_cfg, user_quant) -> str | None:
if hf_quant_cfg is not None:
quant_method = hf_quant_cfg.get("quant_method", None)
if not quant_method and torch.npu.is_available():
return ASCEND_QUANTIZATION_METHOD
return None
def quant_prefix_mapper(self, model_type: str, prefix: str) -> str:
# TODO (Levi-JQ): will be removed when QuantizationConfig.apply_vllm_mapper is implemented
prefix_mapping = QUANT_MODEL_PREFIX_MAPPINGS.get(model_type)
if prefix_mapping:
hf_to_vllm_mapper = WeightsMapper(orig_to_new_prefix=prefix_mapping)
return hf_to_vllm_mapper._map_name(prefix)
return prefix
def get_quant_method(self, layer: torch.nn.Module, prefix: str) -> Optional["QuantizeMethodBase"]:
from .method_adapters import (
AscendEmbeddingMethod,
AscendFusedMoEMethod,
AscendKVCacheMethod,
AscendLinearMethod,
)
vllm_config = get_current_vllm_config()
model_type = vllm_config.model_config.hf_config.model_type
if model_type in ["minimax", "minimax_m2"]:
# Adapt to Minimax architecture: update layer names to MoE convention
prefix = prefix.replace("mlp", "block_sparse_moe")
# Normalize the prefix by stripping specific expert indices (e.g., 'experts.0' -> 'experts')
parts = prefix.split(".")
if "experts" in parts and len(parts) > 2:
exp_idx = parts.index("experts")
if exp_idx + 1 < len(parts) and parts[exp_idx + 1].isdigit():
parts = parts[: exp_idx + 1]
prefix = ".".join(parts)
if model_type in packed_modules_model_mapping:
self.packed_modules_mapping = packed_modules_model_mapping[model_type]
prefix = self.quant_prefix_mapper(model_type, prefix)
from vllm_ascend.utils import vllm_version_is
if vllm_version_is("v0.15.0"):
from vllm.attention.layer import Attention # type: ignore
else:
from vllm.model_executor.layers.attention import Attention
if model_type != "kimi_k2":
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):
# Delayed import to avoid circular import
from vllm_ascend.ops.linear import AscendUnquantizedLinearMethod
return AscendUnquantizedLinearMethod()
scheme = create_scheme_for_layer(self.quant_description, prefix, "linear", self.packed_modules_mapping)
return AscendLinearMethod(scheme)
elif (
isinstance(layer, Attention)
and "fa_quant_type" in self.quant_description
and self.quant_description["fa_quant_type"] is not None
):
scheme = create_scheme_for_layer(self.quant_description, prefix, "attention", self.packed_modules_mapping)
return AscendKVCacheMethod(scheme)
elif isinstance(layer, FusedMoE):
if self.is_layer_skipped_ascend(prefix, self.packed_modules_mapping):
# Delayed import to avoid circular import
from vllm_ascend.ops.fused_moe.fused_moe import AscendUnquantizedFusedMoEMethod
return AscendUnquantizedFusedMoEMethod(layer.moe_config)
scheme = create_scheme_for_layer(self.quant_description, prefix, "moe", self.packed_modules_mapping)
return AscendFusedMoEMethod(scheme, layer.moe_config)
elif isinstance(layer, VocabParallelEmbedding):
if self.is_layer_skipped_ascend(prefix, self.packed_modules_mapping):
return UnquantizedEmbeddingMethod()
scheme = create_scheme_for_layer(self.quant_description, prefix, "linear", self.packed_modules_mapping)
return AscendEmbeddingMethod(scheme)
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 maybe_update_config(self, model_name: str) -> None:
"""Load the ModelSlim quantization config from model directory.
This method is called by vllm after get_quant_config() returns
successfully. Since we return an empty list from get_config_filenames()
to bypass vllm's built-in file lookup, we do the actual config loading
here and provide user-friendly error messages when the config is missing.
Args:
model_name: Path to the model directory or model name.
"""
# If quant_description is already populated (e.g. from from_config()),
# there is nothing to do.
if self.quant_description:
return
# Try to find and load the ModelSlim config file
if os.path.isdir(model_name):
config_path = os.path.join(model_name, MODELSLIM_CONFIG_FILENAME)
if os.path.isfile(config_path):
with open(config_path) as f:
self.quant_description = json.load(f)
self._apply_extra_quant_adaptations()
return
# Check if there are any json files at all to help diagnose
json_files = glob.glob(os.path.join(model_name, "*.json"))
json_names = [os.path.basename(f) for f in json_files]
else:
json_names = []
# Config file not found - raise a friendly error message
raise ValueError(
"\n"
+ "=" * 80
+ "\n"
+ "ERROR: ModelSlim Quantization Config Not Found\n"
+ "=" * 80
+ "\n"
+ "\n"
+ f"You have enabled '--quantization {ASCEND_QUANTIZATION_METHOD}' "
+ "(ModelSlim quantization),\n"
+ f"but the model at '{model_name}' does not contain the required\n"
+ f"quantization config file ('{MODELSLIM_CONFIG_FILENAME}').\n"
+ "\n"
+ "This usually means the model weights are NOT quantized by "
+ "ModelSlim.\n"
+ "\n"
+ "Please choose one of the following solutions:\n"
+ "\n"
+ " Solution 1: Remove the quantization option "
+ "(for float/unquantized models)\n"
+ " "
+ "-" * 58
+ "\n"
+ f" Remove '--quantization {ASCEND_QUANTIZATION_METHOD}' from "
+ "your command if you want to\n"
+ " run the model with the original (float) weights.\n"
+ "\n"
+ " Example:\n"
+ f" vllm serve {model_name}\n"
+ "\n"
+ " Solution 2: Quantize your model weights with ModelSlim first\n"
+ " "
+ "-" * 58
+ "\n"
+ " Use the ModelSlim tool to quantize your model weights "
+ "before deployment.\n"
+ " After quantization, the model directory should contain "
+ f"'{MODELSLIM_CONFIG_FILENAME}'.\n"
+ " For more information, please refer to:\n"
+ " https://gitee.com/ascend/msit/tree/master/msmodelslim\n"
+ "\n"
+ (f" (Found JSON files in model directory: {json_names})\n" if json_names else "")
+ "=" * 80
)
def _apply_extra_quant_adaptations(self) -> None:
"""Apply extra adaptations to the quant_description dict.
This handles known key transformations such as shared_head and
weight_packed mappings.
"""
extra_quant_dict = {}
for k in self.quant_description:
if "shared_head" in k:
new_k = k.replace(".shared_head.", ".")
extra_quant_dict[new_k] = self.quant_description[k]
if "weight_packed" in k:
new_k = k.replace("weight_packed", "weight")
extra_quant_dict[new_k] = self.quant_description[k]
self.quant_description.update(extra_quant_dict)
def get_scaled_act_names(self) -> list[str]:
return []