[CORE] [QUANT] Support for GPTQModel's dynamic quantization per module override/control (#7086)

tests/quantization/test_gptq_dynamic.py

@@ -0,0 +1,68 @@
+# SPDX-License-Identifier: Apache-2.0
+"""Tests whether gptq models with dynamic quantized can be loaded.
+
+Run `pytest tests/quantization/test_gptq_dynamic.py --forked`.
+"""
+
+import pytest
+import torch
+
+from vllm.model_executor.layers.linear import UnquantizedLinearMethod
+from vllm.model_executor.layers.quantization.gptq import GPTQLinearMethod
+from vllm.model_executor.layers.quantization.gptq_marlin import (
+    GPTQMarlinLinearMethod)
+from vllm.model_executor.layers.quantization.utils.gptq_utils import (
+    get_dynamic_override)
+
+PROMPT = "On the surface of Mars, we found"
+
+# The first layer is quantized using bits=4, group_size=128
+# The second layer is quantized using bits=8, group_size=32
+# All other layers (layer index >= 2) are not quantized
+MODEL_QUANT = [
+    ("ModelCloud/Qwen1.5-1.8B-Chat-GPTQ-4bits-dynamic-cfg-with-lm_head-symTrue",
+     True),
+    ("ModelCloud/Qwen1.5-1.8B-Chat-GPTQ-4bits-dynamic-cfg-with-lm_head-symFalse",
+     False),
+]
+
+
+@pytest.mark.parametrize("model_id, use_marlin_kernel", MODEL_QUANT)
+def test_gptq_with_dynamic(vllm_runner, model_id: str,
+                           use_marlin_kernel: bool):
+
+    vllm_model = vllm_runner(model_id, dtype=torch.float16, max_model_len=2048)
+
+    linear_method_cls = GPTQMarlinLinearMethod if use_marlin_kernel else (
+        GPTQLinearMethod)
+
+    for name, submodule in (vllm_model.model.llm_engine.model_executor.
+                            driver_worker.model_runner.model.named_modules()):
+        if name == "lm_head":
+            assert isinstance(submodule.quant_method, linear_method_cls)
+        elif name == 'model.layers.0.self_attn.qkv_proj':
+            # The first layer is quantized using bits=4, group_size=128
+            # desc_act=True
+            assert isinstance(submodule.quant_method, linear_method_cls)
+            config = submodule.quant_method.quant_config
+            assert config.weight_bits == 4
+            assert config.group_size == 128
+            assert config.desc_act
+        elif name == 'model.layers.1.self_attn.qkv_proj':
+            # The second layer is quantized using bits=8, group_size=32
+            # desc_act=False
+            assert isinstance(submodule.quant_method, linear_method_cls)
+            config = submodule.quant_method.quant_config
+            assert get_dynamic_override(config, layer_name=name,
+                                        key="bits") == 8
+            assert get_dynamic_override(config,
+                                        layer_name=name,
+                                        key="group_size") == 32
+            assert not get_dynamic_override(
+                config, layer_name=name, key="desc_act")
+        elif (name == 'model.layers.2.self_attn.qkv_proj'
+              or name == 'model.layers.2.mlp.gate_up_proj'):
+            # All other layers (layer index >= 2) are not quantized
+            assert isinstance(submodule.quant_method, UnquantizedLinearMethod)
+
+    del vllm_model