[NVIDIA][test] Tests for flashinfer TRTLLM BF16 MoE (#33715)

Signed-off-by: Linda-Stadter <57756729+Linda-Stadter@users.noreply.github.com>
Co-authored-by: Pavani Majety <pmajety@nvidia.com>

tests/evals/gsm8k/configs/moe-refactor/Llama-4-Scout-BF16-fi-cutlass.yaml

@@ -5,3 +5,5 @@ num_fewshot: 5
 server_args: "--enforce-eager --max-model-len 8192 --tensor-parallel-size 2 --enable-expert-parallel"
 env:
   VLLM_USE_FLASHINFER_MOE_FP16: "1"
+  VLLM_FLASHINFER_MOE_BACKEND: "throughput"
+

tests/evals/gsm8k/configs/moe-refactor/Mixtral-8x7B-BF16-fi-cutlass.yaml

@@ -5,3 +5,4 @@ num_fewshot: 5
 server_args: "--enforce-eager --max-model-len 8192 --tensor-parallel-size 2 --enable-expert-parallel"
 env:
   VLLM_USE_FLASHINFER_MOE_FP16: "1"
+  VLLM_FLASHINFER_MOE_BACKEND: "throughput"

tests/kernels/moe/test_flashinfer.py

@@ -318,3 +318,44 @@ def test_flashinfer_cutlass_moe_fp8_no_graph(
         torch.testing.assert_close(
             output, flashinfer_cutlass_output, atol=5.5e-2, rtol=1e-2
         )
+
+
+@pytest.mark.parametrize(
+    "num_experts,intermediate,hidden",
+    [
+        (8, 2048, 1536),
+        (64, 4096, 4096),
+    ],
+)
+def test_convert_moe_weights_to_flashinfer_trtllm_block_layout(
+    num_experts, intermediate, hidden
+):
+    from vllm.model_executor.layers.quantization.utils.flashinfer_utils import (
+        convert_moe_weights_to_flashinfer_trtllm_block_layout,
+    )
+
+    w13 = torch.randn(
+        (num_experts, 2 * intermediate, hidden), dtype=torch.bfloat16, device="cuda"
+    )
+    w2 = torch.randn(
+        (num_experts, hidden, intermediate), dtype=torch.bfloat16, device="cuda"
+    )
+
+    cache: dict[torch.Size, torch.Tensor] = {}
+    w13_converted, w2_converted = convert_moe_weights_to_flashinfer_trtllm_block_layout(
+        cache, w13, w2
+    )
+
+    assert w13_converted.ndim == 4, (
+        f"Expected 4D tensor, got shape {w13_converted.shape}"
+    )
+    assert w2_converted.ndim == 4, f"Expected 4D tensor, got shape {w2_converted.shape}"
+
+    assert w13_converted.numel() == w13.numel(), "W13 element count should be preserved"
+    assert w2_converted.numel() == w2.numel(), "W2 element count should be preserved"
+
+    assert w13_converted.dtype == torch.bfloat16
+    assert w2_converted.dtype == torch.bfloat16
+
+    assert w13_converted.shape[0] == num_experts
+    assert w2_converted.shape[0] == num_experts

tests/kernels/moe/test_moe.py

@@ -1558,3 +1558,103 @@ def test_batched_fused_marlin_moe(
     marlin_output = br.run(a, kwargs)
 
     torch.testing.assert_close(marlin_output, ref_marlin_output, atol=1e-3, rtol=0)
+
+
+@pytest.mark.parametrize("m,n,k", [(32, 1024, 1024)])
+@pytest.mark.parametrize("e,topk", [(8, 2)])
+@pytest.mark.parametrize("dtype", [torch.bfloat16])
+@pytest.mark.skipif(
+    not current_platform.is_device_capability_family(100),
+    reason="TRTLLM backend test only runs on Blackwell GPUs (SM10x).",
+)
+def test_unquantized_bf16_flashinfer_trtllm_backend(
+    m: int,
+    n: int,
+    k: int,
+    e: int,
+    topk: int,
+    dtype: torch.dtype,
+    monkeypatch,
+    workspace_init,
+):
+    """
+    Test BF16 unquantized MoE with FlashInfer TRTLLM backend.
+    """
+    set_random_seed(7)
+
+    monkeypatch.setenv("VLLM_USE_FLASHINFER_MOE_FP16", "1")
+
+    from vllm.model_executor.layers.fused_moe.config import (
+        FusedMoEConfig,
+        FusedMoEParallelConfig,
+        RoutingMethodType,
+    )
+    from vllm.model_executor.layers.fused_moe.oracle.unquantized import (
+        UnquantizedMoeBackend,
+    )
+    from vllm.model_executor.layers.fused_moe.unquantized_fused_moe_method import (
+        UnquantizedFusedMoEMethod,
+    )
+
+    # Setup test data
+    a = torch.randn((m, k), device="cuda", dtype=dtype) / 10
+    w1 = torch.randn((e, 2 * n, k), device="cuda", dtype=dtype) / 10
+    w2 = torch.randn((e, k, n), device="cuda", dtype=dtype) / 10
+    router_logits = torch.randn((m, e), device="cuda", dtype=dtype)
+
+    moe_config = FusedMoEConfig(
+        num_experts=e,
+        experts_per_token=topk,
+        hidden_dim=k,
+        intermediate_size_per_partition=n,
+        num_local_experts=e,
+        activation="silu",
+        device="cuda",
+        moe_parallel_config=FusedMoEParallelConfig.make_no_parallel(),
+        in_dtype=dtype,
+        is_act_and_mul=True,
+        routing_method=RoutingMethodType.Renormalize,
+        max_num_tokens=m,
+    )
+
+    with set_current_vllm_config(vllm_config):
+        quant_method = UnquantizedFusedMoEMethod(moe_config)
+
+        # Verify TRTLLM backend was selected
+        assert (
+            quant_method.unquantized_backend == UnquantizedMoeBackend.FLASHINFER_TRTLLM
+        ), f"Expected FLASHINFER_TRTLLM backend, got {quant_method.unquantized_backend}"
+
+        # Verify it's using monolithic path
+        assert quant_method.is_monolithic, (
+            "FLASHINFER_TRTLLM backend should use monolithic forward"
+        )
+        layer = torch.nn.Module()
+        layer.w13_weight = Parameter(w1.clone(), requires_grad=False)
+        layer.w2_weight = Parameter(w2.clone(), requires_grad=False)
+        layer.global_num_experts = e
+        layer.local_num_experts = e
+        layer.top_k = topk
+        layer.num_expert_group = 1
+        layer.topk_group = 1
+        layer.intermediate_size_per_partition = n
+        layer.ep_rank = 0
+        layer.activation = "silu"
+        layer.e_score_correction_bias = None
+        layer.routing_method_type = RoutingMethodType.Renormalize
+
+        quant_method.process_weights_after_loading(layer)
+
+        trtllm_output = quant_method.forward_monolithic_cuda(
+            layer=layer,
+            x=a,
+            router_logits=router_logits,
+        )
+
+        # Compute torch baseline
+        w1_original = w1.clone()
+        w2_original = w2.clone()
+        baseline_output = torch_moe(a, w1_original, w2_original, router_logits, topk)
+
+    close = torch.isclose(trtllm_output, baseline_output, atol=1e-1, rtol=0.85)
+    assert close.float().mean() > 0.925

tests/kernels/moe/test_unquantized_backend_selection.py

+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+from unittest.mock import patch
+
+import pytest
+
+from tests.kernels.moe.utils import make_dummy_moe_config
+from vllm.model_executor.layers.fused_moe.oracle.unquantized import (
+    UnquantizedMoeBackend,
+    select_unquantized_moe_backend,
+)
+
+
+@pytest.mark.parametrize(
+    "platform_method,expected_backend",
+    [
+        ("is_cuda", UnquantizedMoeBackend.TRITON),  # Default CUDA without FlashInfer
+        ("is_rocm", UnquantizedMoeBackend.TRITON),
+        ("is_cpu", UnquantizedMoeBackend.CPU),
+        ("is_xpu", UnquantizedMoeBackend.XPU),
+        ("is_tpu", UnquantizedMoeBackend.TPU),
+        ("is_out_of_tree", UnquantizedMoeBackend.OOT),
+    ],
+)
+@patch(
+    "vllm.model_executor.layers.fused_moe.oracle.unquantized.has_flashinfer",
+    return_value=False,
+)
+def test_select_default_backend_by_platform(
+    mock_has_flashinfer,
+    monkeypatch,
+    platform_method,
+    expected_backend,
+):
+    """Test backend selection for different platforms."""
+    with patch(
+        "vllm.model_executor.layers.fused_moe.oracle.unquantized.current_platform"
+    ) as mock_platform:
+        # Set all platform checks to False
+        mock_platform.is_cuda.return_value = False
+        mock_platform.is_rocm.return_value = False
+        mock_platform.is_cpu.return_value = False
+        mock_platform.is_xpu.return_value = False
+        mock_platform.is_tpu.return_value = False
+        mock_platform.is_out_of_tree.return_value = False
+
+        # Set only the specified platform to True
+        getattr(mock_platform, platform_method).return_value = True
+
+        moe_config = make_dummy_moe_config()
+        selected_backend = select_unquantized_moe_backend(
+            moe_config=moe_config,
+            use_ep=False,
+            use_dp=False,
+        )
+
+        assert selected_backend == expected_backend
+
+
+@patch(
+    "vllm.model_executor.layers.fused_moe.oracle.unquantized.has_flashinfer",
+    return_value=True,
+)
+@patch(
+    "vllm.model_executor.layers.fused_moe.oracle.unquantized.is_supported_config_trtllm_bf16",
+    return_value=(True, None),
+)
+def test_select_cuda_flashinfer_trtllm_backend(
+    mock_has_flashinfer, mock_is_supported_trtllm, monkeypatch
+):
+    """Test CUDA backend selection when FlashInfer TRTLLM is available and enabled."""
+    with patch(
+        "vllm.model_executor.layers.fused_moe.oracle.unquantized.current_platform"
+    ) as mock_platform:
+        # Set as CUDA platform
+        mock_platform.is_cuda.return_value = True
+        mock_platform.is_rocm.return_value = False
+        mock_platform.is_cpu.return_value = False
+        mock_platform.is_xpu.return_value = False
+        mock_platform.is_tpu.return_value = False
+        mock_platform.is_out_of_tree.return_value = False
+
+        monkeypatch.setenv("VLLM_USE_FLASHINFER_MOE_FP16", "1")
+
+        moe_config = make_dummy_moe_config()
+
+        selected_backend = select_unquantized_moe_backend(
+            moe_config=moe_config,
+            use_ep=True,
+            use_dp=False,
+        )
+
+        assert selected_backend == UnquantizedMoeBackend.FLASHINFER_TRTLLM
+
+
+@patch(
+    "vllm.model_executor.layers.fused_moe.oracle.unquantized.has_flashinfer",
+    return_value=True,
+)
+@patch(
+    "vllm.model_executor.layers.fused_moe.oracle.unquantized.is_supported_config_trtllm_bf16",
+    return_value=(False, None),
+)
+def test_select_cuda_flashinfer_cutlass_backend(
+    mock_has_flashinfer, mock_is_supported_trtllm, monkeypatch
+):
+    """Test CUDA backend selection when FlashInfer TRTLLM is not available
+    and FlashInfer CUTLASS is available."""
+    with patch(
+        "vllm.model_executor.layers.fused_moe.oracle.unquantized.current_platform"
+    ) as mock_platform:
+        # Set as CUDA platform with Hopper capability
+        mock_platform.is_cuda.return_value = True
+        mock_platform.is_rocm.return_value = False
+        mock_platform.is_cpu.return_value = False
+        mock_platform.is_xpu.return_value = False
+        mock_platform.is_tpu.return_value = False
+        mock_platform.is_out_of_tree.return_value = False
+        mock_platform.has_device_capability.return_value = True  # SM90+
+
+        # Enable FlashInfer via env var
+        monkeypatch.setenv("VLLM_USE_FLASHINFER_MOE_FP16", "1")
+
+        moe_config = make_dummy_moe_config()
+
+        selected_backend = select_unquantized_moe_backend(
+            moe_config=moe_config,
+            use_ep=True,  # CUTLASS requires EP
+            use_dp=False,  # CUTLASS doesn't support DP
+        )
+
+        assert selected_backend == UnquantizedMoeBackend.FLASHINFER_CUTLASS

tests/quantization/test_blackwell_moe.py

@@ -178,3 +178,11 @@ def test_gptoss_eager(monkeypatch: pytest.MonkeyPatch):
         hf_overrides=HF_OVERRIDE_TEXT,
         extra_args=["--enforce-eager"],
     )
+
+
+## Qwen3 Next ##
+
+
+def test_qwen3_next_bf16_moe_flashinfer_trtllm(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setenv("VLLM_USE_FLASHINFER_MOE_FP16", "1")
+    can_initialize("Qwen/Qwen3-Next-80B-A3B-Instruct", hf_overrides=HF_OVERRIDE_TEXT)

vllm/model_executor/layers/fused_moe/oracle/unquantized.py

@@ -78,7 +78,10 @@ def select_unquantized_moe_backend(
         activation_format=activation_format,
     )
     flashinfer_trtllm_moe_enabled = (
-        has_flashinfer() and envs.VLLM_USE_FLASHINFER_MOE_FP16 and trtllm_supported
+        has_flashinfer()
+        and envs.VLLM_USE_FLASHINFER_MOE_FP16
+        and trtllm_supported
+        and envs.VLLM_FLASHINFER_MOE_BACKEND == "latency"
     )
     # FlashInfer CUTLASS MoE is only supported on Hopper and later GPUS
     flashinfer_cutlass_moe_enabled = (
@@ -98,11 +101,19 @@ def select_unquantized_moe_backend(
             backend = UnquantizedMoeBackend.FLASHINFER_TRTLLM
         elif flashinfer_cutlass_moe_enabled:
             backend = UnquantizedMoeBackend.FLASHINFER_CUTLASS
+            if trtllm_supported:
+                logger.info_once(
+                    "FlashInfer TRTLLM MoE is available but not enabled, "
+                    "consider setting VLLM_FLASHINFER_MOE_BACKEND=latency "
+                    "to enable it for better performance.",
+                    scope="local",
+                )
         else:
             if not envs.VLLM_USE_FLASHINFER_MOE_FP16 and trtllm_supported:
                 logger.info_once(
                     "FlashInfer TRTLLM MoE is available but not enabled, "
                     "consider setting VLLM_USE_FLASHINFER_MOE_FP16=1 "
+                    "and VLLM_FLASHINFER_MOE_BACKEND=latency "
                     "to enable it for better performance.",
                     scope="local",
                 )