[Model] Support GLM-5.3 Flash NVFP4 loading (#38621)

Co-authored-by: YAMY <74099316+YAMY1234@users.noreply.github.com>

python/sglang/srt/models/glm5_next.py

@@ -94,6 +94,7 @@ from sglang.srt.models.glm_ocr import (
     GlmOcrVisionPatchEmbed,
     GlmOcrVisionPatchMerger,
 )
+from sglang.srt.models.utils import WeightsMapper
 from sglang.srt.multimodal.mm_utils import (
     run_dp_presharded_mrope_vision_model,
     run_dp_sharded_mrope_vision_model,
@@ -1077,6 +1078,13 @@ class Glm5NextModel(nn.Module):
 
 
 class Glm5NextForConditionalGeneration(nn.Module):
+    hf_to_sglang_mapper = WeightsMapper(
+        orig_to_new_substr={
+            "model.language_model.": "model.",
+            "model.visual": "visual",
+        }
+    )
+
     packed_modules_mapping = {
         "fused_qkv_a_proj_with_mqa": ["q_a_proj", "kv_a_proj_with_mqa"],
         "fused_qkvbfg_a_proj": [
@@ -1200,6 +1208,17 @@ class Glm5NextForConditionalGeneration(nn.Module):
         text_config = getattr(hf_config, "text_config", hf_config)
         if not getattr(text_config, "n_shared_experts", None):
             return "No shared experts are defined in the config."
+        if quant_config is not None and quant_config.get_name() == "modelopt_fp4":
+            first_sparse_layer = getattr(text_config, "first_k_dense_replace", 0)
+            for layer_id in range(first_sparse_layer, text_config.num_hidden_layers):
+                moe_prefix = f"model.layers.{layer_id}.mlp"
+                if quant_config.is_layer_excluded(
+                    f"{moe_prefix}.shared_experts"
+                ) and not quant_config.is_layer_excluded(f"{moe_prefix}.experts"):
+                    return (
+                        "ModelOpt FP4 keeps shared experts unquantized while routed "
+                        "experts are quantized."
+                    )
         if not _is_cuda:
             return "Shared experts fusion currently requires CUDA devices."
         if _device_sm is not None and _device_sm < 80:

test/registered/unit/models/test_glm5_next_modelopt.py

@@ -0,0 +1,104 @@
+import unittest
+from types import SimpleNamespace
+from unittest.mock import patch
+
+from sglang.srt.layers.quantization.modelopt_quant import ModelOptFp4Config
+from sglang.srt.models import glm5_next
+from sglang.srt.models.glm5_next import Glm5NextForConditionalGeneration
+from sglang.srt.runtime_context import get_parallel
+from sglang.test.ci.ci_register import register_cpu_ci
+from sglang.test.test_utils import CustomTestCase
+
+register_cpu_ci(est_time=5, suite="base-a-test-cpu")
+
+NVIDIA_EXCLUDE_MODULES = [
+    "model.language_model.embed_tokens",
+    "model.language_model.layers.11.self_attn*",
+    "model.language_model.layers.11.mlp.gate",
+    "model.language_model.layers.11.mlp.shared_experts*",
+    "model.visual*",
+]
+
+RADIXARK_EXCLUDE_MODULES = [
+    "model.language_model.embed_tokens",
+    "model.language_model.layers.11.self_attn*",
+    "model.language_model.layers.11.mlp.gate",
+    "model.visual*",
+    "model.embed_tokens",
+    "model.layers.11.self_attn*",
+    "model.layers.11.mlp.gate",
+    "model.language_model.layers.45*",
+    "model.layers.45*",
+    "visual*",
+]
+
+
+class TestGlm5NextModelOpt(CustomTestCase):
+    def _config(self, exclude_modules):
+        config = ModelOptFp4Config(
+            is_checkpoint_nvfp4_serialized=True,
+            group_size=16,
+            exclude_modules=exclude_modules,
+        )
+        config.apply_weight_name_mapper(
+            Glm5NextForConditionalGeneration.hf_to_sglang_mapper
+        )
+        return config
+
+    def _hf_config(self):
+        return SimpleNamespace(
+            text_config=SimpleNamespace(
+                first_k_dense_replace=3,
+                num_hidden_layers=45,
+                n_shared_experts=1,
+            )
+        )
+
+    def test_checkpoint_exclusions_match_sglang_module_names(self):
+        checkpoints = {
+            "nvidia/GLM-5.3-Flash-NVFP4": NVIDIA_EXCLUDE_MODULES,
+            "RadixArk/GLM-5.3-Flash-NVFP4": RADIXARK_EXCLUDE_MODULES,
+        }
+
+        for checkpoint, exclude_modules in checkpoints.items():
+            with self.subTest(checkpoint=checkpoint):
+                config = self._config(exclude_modules)
+                self.assertTrue(config.is_layer_excluded("model.embed_tokens"))
+                self.assertTrue(
+                    config.is_layer_excluded("model.layers.11.self_attn.kv_b_proj")
+                )
+                self.assertTrue(config.is_layer_excluded("model.layers.11.mlp.gate"))
+                self.assertTrue(
+                    config.is_layer_excluded("visual.blocks.0.attn.qkv_proj")
+                )
+
+    def test_nvidia_mixed_precision_shared_experts_disable_fusion(self):
+        config = self._config(NVIDIA_EXCLUDE_MODULES)
+
+        reason = Glm5NextForConditionalGeneration.shared_experts_fusion_disable_reason(
+            self._hf_config(), config
+        )
+
+        self.assertIn("shared experts unquantized", reason)
+
+    def test_radixark_uniform_fp4_shared_experts_keep_fusion(self):
+        config = self._config(RADIXARK_EXCLUDE_MODULES)
+        a2a_backend = SimpleNamespace(is_deepep=lambda: False)
+
+        with (
+            patch.object(glm5_next, "_is_cuda", True),
+            patch.object(glm5_next, "_device_sm", 100),
+            patch.object(glm5_next, "get_moe_a2a_backend", return_value=a2a_backend),
+            get_parallel().override(moe_ep_size=1),
+        ):
+            reason = (
+                Glm5NextForConditionalGeneration.shared_experts_fusion_disable_reason(
+                    self._hf_config(), config
+                )
+            )
+
+        self.assertIsNone(reason)
+
+
+if __name__ == "__main__":
+    unittest.main()