flashinfer.py 24.2 KB
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# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
"""Compatibility wrapper for FlashInfer API changes.

Users of vLLM should always import **only** these wrappers.
"""
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import contextlib
import functools
import importlib
import importlib.util
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import os
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import shutil
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from collections.abc import Callable
from typing import Any, NoReturn
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import requests
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import torch
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import vllm.envs as envs
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from vllm.logger import init_logger
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from vllm.model_executor.layers.batch_invariant import (
    vllm_is_batch_invariant,
)
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from vllm.platforms import current_platform
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logger = init_logger(__name__)

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# This is the storage path for the cubins, it can be replaced
# with a local path for testing.
# Referenced from https://github.com/flashinfer-ai/flashinfer/blob/0c9a92c3d9a7e043ab6f3f7b2273269caf6ab044/flashinfer/jit/cubin_loader.py#L35  # noqa: E501
FLASHINFER_CUBINS_REPOSITORY = os.environ.get(
    "FLASHINFER_CUBINS_REPOSITORY",
    "https://edge.urm.nvidia.com/artifactory/sw-kernelinferencelibrary-public-generic-local/",  # noqa: E501
)

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@functools.cache
def has_flashinfer_cubin() -> bool:
    """Return `True` if flashinfer-cubin package is available."""
    if envs.VLLM_HAS_FLASHINFER_CUBIN:
        return True
    if importlib.util.find_spec("flashinfer_cubin") is not None:
        return True
    logger.debug_once("flashinfer-cubin package was not found")
    return False


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@functools.cache
def has_flashinfer() -> bool:
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    """Return `True` if flashinfer-python package is available."""
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    # Use find_spec to check if the module exists without importing it
    # This avoids potential CUDA initialization side effects
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    if importlib.util.find_spec("flashinfer") is None:
        logger.debug_once("FlashInfer unavailable since package was not found")
        return False
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    # When not using flashinfer cubin,
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    # Also check if nvcc is available since it's required to JIT compile flashinfer
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    if not has_flashinfer_cubin() and shutil.which("nvcc") is None:
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        logger.debug_once(
            "FlashInfer unavailable since nvcc was not found "
            "and not using pre-downloaded cubins"
        )
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        return False
    return True
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def _missing(*_: Any, **__: Any) -> NoReturn:
    """Placeholder for unavailable FlashInfer backend."""
    raise RuntimeError(
        "FlashInfer backend is not available. Please install the package "
        "to enable FlashInfer kernels: "
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        "https://github.com/flashinfer-ai/flashinfer"
    )
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def _get_submodule(module_name: str) -> Any | None:
    """Safely import a submodule and return it, or None if not available."""
    try:
        return importlib.import_module(module_name)
    except (ImportError, ModuleNotFoundError):
        return None


# General lazy import wrapper
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def _lazy_import_wrapper(
    module_name: str, attr_name: str, fallback_fn: Callable[..., Any] = _missing
):
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    """Create a lazy import wrapper for a specific function."""

    @functools.cache
    def _get_impl():
        if not has_flashinfer():
            return None
        mod = _get_submodule(module_name)
        return getattr(mod, attr_name, None) if mod else None

    def wrapper(*args, **kwargs):
        impl = _get_impl()
        if impl is None:
            return fallback_fn(*args, **kwargs)
        return impl(*args, **kwargs)

    return wrapper


# Create lazy wrappers for each function
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flashinfer_trtllm_bf16_moe = _lazy_import_wrapper(
    "flashinfer.fused_moe", "trtllm_bf16_moe"
)
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flashinfer_trtllm_fp8_block_scale_moe = _lazy_import_wrapper(
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    "flashinfer.fused_moe", "trtllm_fp8_block_scale_moe"
)
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flashinfer_trtllm_fp8_per_tensor_scale_moe = _lazy_import_wrapper(
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    "flashinfer.fused_moe", "trtllm_fp8_per_tensor_scale_moe"
)
flashinfer_cutlass_fused_moe = _lazy_import_wrapper(
    "flashinfer.fused_moe", "cutlass_fused_moe"
)
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flashinfer_cutedsl_grouped_gemm_nt_masked = _lazy_import_wrapper(
    "flashinfer.cute_dsl.blockscaled_gemm", "grouped_gemm_nt_masked"
)
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flashinfer_fp4_quantize = _lazy_import_wrapper("flashinfer", "fp4_quantize")
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nvfp4_batched_quantize = _lazy_import_wrapper("flashinfer", "nvfp4_batched_quantize")
silu_and_mul_scaled_nvfp4_experts_quantize = _lazy_import_wrapper(
    "flashinfer", "silu_and_mul_scaled_nvfp4_experts_quantize"
)
scaled_fp4_grouped_quantize = _lazy_import_wrapper(
    "flashinfer", "scaled_fp4_grouped_quantize"
)
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nvfp4_block_scale_interleave = _lazy_import_wrapper(
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    "flashinfer.fp4_quantization", "block_scale_interleave"
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)
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trtllm_fp4_block_scale_moe = _lazy_import_wrapper(
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    "flashinfer", "trtllm_fp4_block_scale_moe"
)
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# Special case for autotune since it returns a context manager
autotune = _lazy_import_wrapper(
    "flashinfer.autotuner",
    "autotune",
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    fallback_fn=lambda *args, **kwargs: contextlib.nullcontext(),
)
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@functools.cache
def has_flashinfer_comm() -> bool:
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    """Return `True` if FlashInfer comm module is available."""
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    return has_flashinfer() and importlib.util.find_spec("flashinfer.comm") is not None
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@functools.cache
def has_flashinfer_all2all() -> bool:
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    """Return `True` if FlashInfer mnnvl all2all is available."""
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    if not has_flashinfer_comm():
        return False

    # Check if all required functions are available
    required_functions = [
        ("flashinfer.comm", "Mapping"),
        ("flashinfer.comm.mnnvl", "MnnvlMemory"),
        ("flashinfer.comm.trtllm_alltoall", "MnnvlMoe"),
        ("flashinfer.comm.trtllm_alltoall", "MoEAlltoallInfo"),
    ]

    for module_name, attr_name in required_functions:
        mod = _get_submodule(module_name)
        if not mod or not hasattr(mod, attr_name):
            return False
    return True


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@functools.cache
def has_flashinfer_moe() -> bool:
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    """Return `True` if FlashInfer MoE module is available."""
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    return (
        has_flashinfer()
        and importlib.util.find_spec("flashinfer.fused_moe") is not None
    )
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@functools.cache
def has_flashinfer_cutedsl() -> bool:
    """Return ``True`` if FlashInfer cutedsl module is available."""
    return (
        has_flashinfer() and importlib.util.find_spec("flashinfer.cute_dsl") is not None
    )


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@functools.cache
def has_flashinfer_trtllm_fused_moe() -> bool:
    """Return `True` if FlashInfer TRTLLM fused MoE is available."""
    if not has_flashinfer_moe():
        return False
    required_functions = [
        ("flashinfer.fused_moe", "trtllm_fp8_block_scale_moe"),
        ("flashinfer.fused_moe", "trtllm_fp8_per_tensor_scale_moe"),
        ("flashinfer.fused_moe", "trtllm_fp4_block_scale_moe"),
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        ("flashinfer.fused_moe", "trtllm_mxint4_block_scale_moe"),
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    ]
    for module_name, attr_name in required_functions:
        mod = _get_submodule(module_name)
        if not mod or not hasattr(mod, attr_name):
            return False
    return True


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@functools.cache
def has_flashinfer_cutlass_fused_moe() -> bool:
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    """Return `True` if FlashInfer CUTLASS fused MoE is available."""
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    if not has_flashinfer_moe():
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        return False

    # Check if all required functions are available
    required_functions = [
        ("flashinfer.fused_moe", "cutlass_fused_moe"),
        ("flashinfer", "fp4_quantize"),
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        ("flashinfer", "nvfp4_block_scale_interleave"),
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        ("flashinfer.fused_moe", "trtllm_fp4_block_scale_moe"),
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    ]

    for module_name, attr_name in required_functions:
        mod = _get_submodule(module_name)
        if not mod or not hasattr(mod, attr_name):
            return False
    return True


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@functools.cache
def has_flashinfer_cutedsl_grouped_gemm_nt_masked() -> bool:
    """Return ``True`` if FlashInfer CUTLASS fused MoE is available."""
    if not has_flashinfer_cutedsl():
        return False

    # Check if all required functions are available
    required_functions = [
        ("flashinfer.cute_dsl.blockscaled_gemm", "grouped_gemm_nt_masked"),
        ("flashinfer", "scaled_fp4_grouped_quantize"),
        ("flashinfer", "silu_and_scaled_nvfp4_experts_quantize"),
    ]

    for module_name, attr_name in required_functions:
        mod = _get_submodule(module_name)
        if not mod or not hasattr(mod, attr_name):
            return False
    return True


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@functools.cache
def has_nvidia_artifactory() -> bool:
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    """Return `True` if NVIDIA's artifactory is accessible.
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    This checks connectivity to the kernel inference library artifactory
    which is required for downloading certain cubin kernels like TRTLLM FHMA.
    """
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    # If we have pre-downloaded cubins, we can assume the cubins are available.
    if has_flashinfer_cubin():
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        return True

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    try:
        # Use a short timeout to avoid blocking for too long
        response = requests.get(FLASHINFER_CUBINS_REPOSITORY, timeout=5)
        accessible = response.status_code == 200
        if accessible:
            logger.debug_once("NVIDIA artifactory is accessible")
        else:
            logger.warning_once(
                "NVIDIA artifactory returned failed status code: %d",
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                response.status_code,
            )
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        return accessible
    except Exception as e:
        logger.warning_once("Failed to connect to NVIDIA artifactory: %s", e)
        return False


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@functools.cache
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def supports_trtllm_attention() -> bool:
    """
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    TRTLLM attention is supported if the platform is SM100,
    NVIDIA artifactory is accessible, and batch-invariant mode is not enabled.
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    """
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    # Batch-invariant mode disables TRTLLM attention
    if vllm_is_batch_invariant():
        return False

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    # Requires SM100 and NVIDIA artifactory to be accessible to download cubins
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    return (
        current_platform.is_device_capability_family(100) and has_nvidia_artifactory()
    )
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def force_use_trtllm_attention() -> bool | None:
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    """
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    This function should only be called during initialization stage when vllm config
    is set.
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    Return `None` if --attention-config.use_trtllm_attention is not set,
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    return `True` if TRTLLM attention is forced to be used,
    return `False` if TRTLLM attention is forced to be not used.
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    """
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    from vllm.config import get_current_vllm_config

    vllm_config = get_current_vllm_config()
    return vllm_config.attention_config.use_trtllm_attention
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def can_use_trtllm_attention(num_qo_heads: int, num_kv_heads: int) -> bool:
    """Check if the current configuration supports TRTLLM attention."""
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    if force_use_trtllm_attention() is False:
        return False
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    has_trtllm = supports_trtllm_attention()
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    return has_trtllm and (num_qo_heads % num_kv_heads == 0)
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def use_trtllm_attention(
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    num_qo_heads: int,
    num_kv_heads: int,
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    num_tokens: int,
    max_seq_len: int,
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    dcp_world_size: int,
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    kv_cache_dtype: str,
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    q_dtype: torch.dtype,
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    is_prefill: bool,
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    # None means auto-detection, True means force on, False means force off
    force_use_trtllm: bool | None = None,
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    has_sinks: bool = False,
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    has_spec: bool = False,
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) -> bool:
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    """Return `True` if TRTLLM attention is used."""
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    # CLI argument is set to 0 - respect it
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    if force_use_trtllm is not None and not force_use_trtllm:
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        return False

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    # Decode context parallel is not supported
    if dcp_world_size > 1:
        logger.warning_once(
            "Trtllm does not support returning LSE and as a result "
            "does not support DCP, reverting to FlashInfer"
        )
        return False

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    # The platform is not supported
    if not supports_trtllm_attention():
        if force_use_trtllm:
            logger.warning_once(
                "TRTLLM attention is not supported on this platform, "
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                "but --attention-config.use_trtllm_attention is set to 1"
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            )
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        return False

    # The combination of query and key heads is not supported
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    if num_qo_heads % num_kv_heads != 0:
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        if force_use_trtllm:
            logger.warning_once(
                "TRTLLM attention is not supported for this combination of "
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                "query and key heads, but --attention-config.use_trtllm_attention is "
                "set to 1"
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            )
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        return False

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    if has_spec and not is_prefill:
        # Speculative decoding requires TRTLLM attention for decodes
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        logger.info_once("Using TRTLLM attention (enabled for speculative decoding).")
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        return True

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    # Must use TRTLLM attention if query is FP8 quantized
    if q_dtype == current_platform.fp8_dtype():
        logger.info_once("Using TRTLLM attention (query is quantized).")
        return True

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    # If sinks are being used, we must use TRTLLM attention as it's
    # the only backend that supports them
    if has_sinks:
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        logger.info_once("Using TRTLLM attention (required for attention sinks).")
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        return True

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    if force_use_trtllm is None:
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        # CLI argument not set - use auto-detection
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        if is_prefill:
            # Prefill auto-detection
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            use_trtllm = kv_cache_dtype == "auto"
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            if use_trtllm:
                logger.warning_once("Using TRTLLM prefill attention (auto-detected).")
        else:
            # Decode auto-detection
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            use_trtllm = num_tokens <= 256 and kv_cache_dtype == "auto"
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            if use_trtllm:
                logger.warning_once("Using TRTLLM decode attention (auto-detected).")
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        return use_trtllm

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    # CLI argument is set to 1 - respect it
    logger.info_once(
        "Using TRTLLM attention (--attention-config.use_trtllm_attention is set to 1)"
    )
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    return True

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if has_flashinfer():
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    from vllm.utils.torch_utils import direct_register_custom_op

    def _flashinfer_concat_mla_k(
        k: torch.Tensor,
        k_nope: torch.Tensor,
        k_pe: torch.Tensor,
    ) -> None:
        """Custom op wrapper for flashinfer's concat_mla_k.

        This is an in-place operation that concatenates k_nope and k_pe into k.

        The kernel is optimized for DeepSeek V3 dimensions:
        - num_heads=128
        - nope_dim=128
        - rope_dim=64

        Key optimizations:
        - Warp-based processing with software pipelining
        - Vectorized memory access (int2 for nope, int for rope)
        - L2 prefetching for next row while processing current
        - Register reuse for rope values across all heads

        Args:
            k: Output tensor, shape [num_tokens, num_heads, nope_dim + rope_dim].
                Modified in-place.
            k_nope: The nope part of k, shape [num_tokens, num_heads, nope_dim].
            k_pe: The rope part of k (shared), shape [num_tokens, 1, rope_dim].
                  This is broadcast to all heads.
        """
        from flashinfer.concat_ops import concat_mla_k

        concat_mla_k(k, k_nope, k_pe)

    def _flashinfer_concat_mla_k_fake(
        k: torch.Tensor,
        k_nope: torch.Tensor,
        k_pe: torch.Tensor,
    ) -> None:
        return

    # Register flashinfer concat_mla_k custom op
    direct_register_custom_op(
        op_name="flashinfer_concat_mla_k",
        op_func=_flashinfer_concat_mla_k,
        mutates_args=["k"],  # k tensor is modified in-place
        fake_impl=_flashinfer_concat_mla_k_fake,
    )
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    @torch.library.custom_op(
        "vllm::flashinfer_mm_fp4",
        mutates_args=[],
        device_types="cuda",
    )
    def flashinfer_mm_fp4(
        A: torch.Tensor,
        B: torch.Tensor,
        A_scale: torch.Tensor,
        B_scale: torch.Tensor,
        g_scale: torch.Tensor,
        dtype: torch.dtype,
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        use_8x4_sf_layout: bool,
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        backend: str,
    ) -> torch.Tensor:
        from flashinfer import mm_fp4 as flashinfer_mm_fp4_
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        return flashinfer_mm_fp4_(
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            A,
            B,
            A_scale,
            B_scale,
            g_scale,
            dtype,
            block_size=16,
            use_8x4_sf_layout=use_8x4_sf_layout,
            backend=backend,
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        )

    @torch.library.register_fake(
        "vllm::flashinfer_mm_fp4",
    )
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    def flashinfer_mm_fp4_fake(
        A: torch.Tensor,
        B: torch.Tensor,
        A_scale: torch.Tensor,
        B_scale: torch.Tensor,
        g_scale: torch.Tensor,
        dtype: torch.dtype,
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        use_8x4_sf_layout: bool,
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        backend: str,
    ) -> torch.Tensor:
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        return torch.empty(A.shape[0], B.shape[1], dtype=dtype, device=A.device)
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    @torch.library.custom_op(
        "vllm::bmm_fp8",
        mutates_args=[],
        device_types="cuda",
    )
    def bmm_fp8(
        A: torch.Tensor,
        B: torch.Tensor,
        A_scale: torch.Tensor,
        B_scale: torch.Tensor,
        dtype: torch.dtype,
        backend: str,
    ) -> torch.Tensor:
        from flashinfer import bmm_fp8 as bmm_fp8_
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        return bmm_fp8_(A, B, A_scale, B_scale, dtype, None, backend)

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    @torch.library.register_fake(
        "vllm::bmm_fp8",
    )
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    def bmm_fp8_fake(
        A: torch.Tensor,
        B: torch.Tensor,
        A_scale: torch.Tensor,
        B_scale: torch.Tensor,
        dtype: torch.dtype,
        backend: str,
    ) -> torch.Tensor:
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        return torch.empty(
            A.shape[0], A.shape[1], B.shape[2], dtype=dtype, device=A.device
        )

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    @torch.library.custom_op(
        "vllm::flashinfer_nvfp4_quantize",
        mutates_args=[],
        device_types="cuda",
    )
    def flashinfer_nvfp4_quantize(
        a: torch.Tensor, a_global_sf: torch.Tensor
    ) -> tuple[torch.Tensor, torch.Tensor]:
        from flashinfer import SfLayout
        from flashinfer import nvfp4_quantize as nvfp4_quantize_

        return nvfp4_quantize_(
            a, a_global_sf, sfLayout=SfLayout.layout_8x4, do_shuffle=False
        )

    @torch.library.register_fake(
        "vllm::flashinfer_nvfp4_quantize",
    )
    def flashinfer_nvfp4_quantize_fake(
        a: torch.Tensor, a_global_sf: torch.Tensor
    ) -> tuple[torch.Tensor, torch.Tensor]:
        m, n = a.shape

        round_up = lambda x, y: (x + y - 1) // y * y

        rounded_m = round_up(m, 8)
        scale_n = n // 16
        rounded_n = round_up(scale_n, 4)

        return torch.empty(m, n // 2, dtype=torch.uint8, device=a.device), torch.empty(
            rounded_m, rounded_n, dtype=torch.uint8, device=a.device
        )

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    @torch.library.custom_op(
        "vllm::mm_mxfp8",
        mutates_args=[],
        device_types="cuda",
    )
    def mm_mxfp8(
        A: torch.Tensor,
        B: torch.Tensor,
        A_scale: torch.Tensor,
        B_scale: torch.Tensor,
        out_dtype: torch.dtype,
        backend: str = "cutlass",
    ) -> torch.Tensor:
        from flashinfer import mm_mxfp8 as mm_mxfp8_

        return mm_mxfp8_(
            A,
            B,
            A_scale,
            B_scale,
            out=None,
            out_dtype=out_dtype,
            backend=backend,
        )

    @torch.library.register_fake(
        "vllm::mm_mxfp8",
    )
    def mm_mxfp8_fake(
        A: torch.Tensor,
        B: torch.Tensor,
        A_scale: torch.Tensor,
        B_scale: torch.Tensor,
        out_dtype: torch.dtype,
        backend: str = "cutlass",
    ) -> torch.Tensor:
        # A is [m, k], B is [k, n] -> output [m, n]
        return torch.empty(A.shape[0], B.shape[1], dtype=out_dtype, device=A.device)


def flashinfer_mm_mxfp8(
    a: torch.Tensor,
    b: torch.Tensor,
    block_scale_a: torch.Tensor,
    block_scale_b: torch.Tensor,
    out_dtype: torch.dtype,
    backend: str = "cutlass",
) -> torch.Tensor:
    """MXFP8 MM helper - mirrors flashinfer_scaled_fp4_mm API.

    Takes non-transposed weights and handles transpose internally.

    CRITICAL: mm_mxfp8 CUTLASS kernel requires SWIZZLED 1D scales for optimal
    performance and accuracy. Both input and weight scales should be in
    swizzled format from FlashInfer's mxfp8_quantize(is_sf_swizzled_layout=True).
    """
    # a shape [M, K]
    # b shape [K, N]
    assert a.ndim == 2 and b.ndim == 2
    assert a.shape[1] == b.shape[1]  # K dimension must match

    if block_scale_b.ndim != 1:
        raise ValueError(
            "mm_mxfp8 expects 1D swizzled weight scales for CUTLASS; "
            f"got shape={tuple(block_scale_b.shape)}"
        )

    # Output tensor [M, N]
    return mm_mxfp8(
        a,
        b.t(),  # Transpose weight: [N, K] -> [K, N]
        block_scale_a,
        block_scale_b,
        out_dtype,
        backend=backend,
    )

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def flashinfer_scaled_fp4_mm(
    a: torch.Tensor,
    b: torch.Tensor,
    block_scale_a: torch.Tensor,
    block_scale_b: torch.Tensor,
    alpha: torch.Tensor,
    out_dtype: torch.dtype,
    backend: str,
) -> torch.Tensor:
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    assert a.ndim == 2 and b.ndim == 2
    assert block_scale_a.ndim == 2 and block_scale_b.ndim == 2
    assert a.stride(-1) == 1 and b.stride(-1) == 1
    assert a.shape[1] == b.shape[1]

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    if backend in ("cutlass", "cudnn"):
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        block_scale_a = block_scale_a.view(torch.uint8)
        block_scale_b = block_scale_b.view(torch.uint8)

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    use_8x4_sf_layout = True if backend == "trtllm" and a.shape[0] <= 32 else False  # noqa: SIM210

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    return flashinfer_mm_fp4(
        a,
        b.t(),
        block_scale_a,
        block_scale_b.t(),
        alpha,
        out_dtype,
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        use_8x4_sf_layout=use_8x4_sf_layout,
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        backend=backend,
    )


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def flashinfer_scaled_fp8_mm(
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    a: torch.Tensor,
    b: torch.Tensor,
    scale_a: torch.Tensor,
    scale_b: torch.Tensor,
    out_dtype: torch.dtype,
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    bias: torch.Tensor | None = None,
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) -> torch.Tensor:
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    assert a.ndim == 2 and b.ndim == 2
    assert a.shape[1] == b.shape[0]
    assert scale_a.numel() == 1 and scale_b.numel() == 1
    assert a.dtype == torch.float8_e4m3fn and b.dtype == torch.float8_e4m3fn
    assert a.device.type == "cuda" and b.device.type == "cuda"
    assert scale_a.dtype == torch.float32 and scale_b.dtype == torch.float32
    assert scale_a.device.type == "cuda" and scale_b.device.type == "cuda"

    output = bmm_fp8(
        a.unsqueeze(0),
        b.unsqueeze(0),
        scale_a,
        scale_b,
        out_dtype,
        "auto",
    ).view(a.shape[0], b.shape[1])

    if bias is not None:
        output = output + bias
    return output


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def flashinfer_quant_nvfp4_8x4_sf_layout(
    a: torch.Tensor, a_global_sf: torch.Tensor
) -> tuple[torch.Tensor, torch.Tensor]:
    return flashinfer_nvfp4_quantize(a, a_global_sf)


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flashinfer_fp8_blockscale_gemm = _lazy_import_wrapper(
    "flashinfer.gemm", "fp8_blockscale_gemm_sm90"
)


@functools.cache
def has_flashinfer_fp8_blockscale_gemm() -> bool:
    """Return `True` if FlashInfer block-scale FP8 GEMM is available."""
    return (
        has_flashinfer()
        and current_platform.is_device_capability(90)
        and hasattr(_get_submodule("flashinfer.gemm"), "fp8_blockscale_gemm_sm90")
    )


@functools.cache
def is_flashinfer_fp8_blockscale_gemm_supported() -> bool:
    """Return `True` if FlashInfer block-scale FP8 GEMM is supported."""
    return (
        envs.VLLM_BLOCKSCALE_FP8_GEMM_FLASHINFER
        and has_flashinfer_fp8_blockscale_gemm()
    )


def should_use_flashinfer_for_blockscale_fp8_gemm(
    is_flashinfer_supported: bool,
    output_dtype: torch.dtype,
    input: torch.Tensor,
    weight: torch.Tensor,
):
    if not is_flashinfer_supported:
        return False

    # Verify DeepGEMM N/K dims requirements
    # NOTE: Also synchronized with test_w8a8_block_fp8_deep_gemm_matmul
    # test inside kernels/quatization/test_block_fp8.py
    N_MULTIPLE = 64
    K_MULTIPLE = 128

    weight_dtype = weight.dtype
    input_dtype = input.dtype

    should_use_flashinfer = (
        output_dtype == torch.bfloat16
        and input_dtype == torch.bfloat16
        and weight_dtype == torch.float8_e4m3fn
        and weight.shape[0] % N_MULTIPLE == 0
        and weight.shape[1] % K_MULTIPLE == 0
    )

    return should_use_flashinfer


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__all__ = [
    "has_flashinfer",
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    "flashinfer_trtllm_fp8_block_scale_moe",
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    "flashinfer_cutlass_fused_moe",
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    "flashinfer_cutedsl_grouped_gemm_nt_masked",
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    "flashinfer_fp4_quantize",
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    "silu_and_mul_scaled_nvfp4_experts_quantize",
    "scaled_fp4_grouped_quantize",
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    "nvfp4_block_scale_interleave",
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    "trtllm_fp4_block_scale_moe",
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    "autotune",
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    "has_flashinfer_moe",
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    "has_flashinfer_comm",
    "has_flashinfer_all2all",
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    "has_flashinfer_cutlass_fused_moe",
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    "has_flashinfer_cutedsl_grouped_gemm_nt_masked",
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    "has_flashinfer_fp8_blockscale_gemm",
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    "has_nvidia_artifactory",
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    "supports_trtllm_attention",
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    "can_use_trtllm_attention",
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    "use_trtllm_attention",
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    "flashinfer_scaled_fp4_mm",
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    "flashinfer_scaled_fp8_mm",
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    "flashinfer_quant_nvfp4_8x4_sf_layout",
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    "flashinfer_fp8_blockscale_gemm",
    "should_use_flashinfer_for_blockscale_fp8_gemm",
    "is_flashinfer_fp8_blockscale_gemm_supported",
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]