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[V1][Attention] Split triton_attn in triton-only and rocm specific backends (#24648)
Signed-off-by: Burkhard Ringlein <ngl@zurich.ibm.com>
This commit is contained in:
parent
c10101a3eb
commit
175811e3b5
@ -1494,6 +1494,7 @@ class EngineArgs:
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"FLEX_ATTENTION",
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"TREE_ATTN",
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"XFORMERS_VLLM_V1",
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"ROCM_ATTN_VLLM_V1",
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]
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if (envs.is_set("VLLM_ATTENTION_BACKEND")
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and envs.VLLM_ATTENTION_BACKEND not in V1_BACKENDS):
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@ -67,6 +67,7 @@ class _Backend(enum.Enum):
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FLEX_ATTENTION = enum.auto()
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TREE_ATTN = enum.auto()
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XFORMERS_VLLM_V1 = enum.auto()
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ROCM_ATTN_VLLM_V1 = enum.auto()
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class PlatformEnum(enum.Enum):
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@ -231,7 +231,17 @@ class RocmPlatform(Platform):
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logger.info("Using Flash Attention backend on V1 engine.")
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return ("vllm.v1.attention.backends."
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"rocm_aiter_fa.AiterFlashAttentionBackend")
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elif (envs.VLLM_ROCM_USE_AITER and
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envs.VLLM_USE_AITER_UNIFIED_ATTENTION) or \
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envs.VLLM_V1_USE_PREFILL_DECODE_ATTENTION or \
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selected_backend == _Backend.ROCM_ATTN_VLLM_V1:
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# rocm specific backend, with aiter and/or
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# triton prefix-prefill
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logger.info("Using Rocm/Aiter Attention backend on V1 engine.")
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return ("vllm.v1.attention.backends."
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"rocm_attn.RocmAttentionBackend")
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else:
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# default case, using triton unified attention
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logger.info("Using Triton Attention backend on V1 engine.")
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return ("vllm.v1.attention.backends."
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"triton_attn.TritonAttentionBackend")
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426
vllm/v1/attention/backends/rocm_attn.py
Normal file
426
vllm/v1/attention/backends/rocm_attn.py
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@ -0,0 +1,426 @@
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# SPDX-License-Identifier: Apache-2.0
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# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
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"""Attention layer with PagedAttention and Triton prefix prefill."""
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from dataclasses import dataclass
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from functools import cache
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from typing import ClassVar, Optional
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import torch
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from vllm import _custom_ops as ops
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from vllm import envs
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from vllm.attention.backends.abstract import (AttentionBackend, AttentionImpl,
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AttentionMetadata, AttentionType)
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from vllm.attention.ops.chunked_prefill_paged_decode import (
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chunked_prefill_paged_decode)
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from vllm.attention.ops.paged_attn import PagedAttention
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from vllm.config import VllmConfig
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from vllm.logger import init_logger
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from vllm.model_executor.layers.quantization.utils.quant_utils import (
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QuantKey, kFp8StaticTensorSym)
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from vllm.platforms import current_platform
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from vllm.v1.attention.backends.flash_attn import FlashAttentionMetadata
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from vllm.v1.attention.backends.utils import (AttentionCGSupport,
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AttentionMetadataBuilder,
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CommonAttentionMetadata)
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from vllm.v1.kv_cache_interface import AttentionSpec
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logger = init_logger(__name__)
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@dataclass
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class RocmAttentionMetadata:
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# NOTE(sang): Definition of context_len, query_len, and seq_len.
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# |---------- N-1 iteration --------|
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# |---------------- N iteration ---------------------|
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# |- tokenA -|......................|-- newTokens ---|
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# |---------- context_len ----------|
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# |-------------------- seq_len ---------------------|
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# |-- query_len ---|
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num_actual_tokens: int # Number of tokens excluding padding.
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max_query_len: int
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query_start_loc: torch.Tensor
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max_seq_len: int
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seq_lens: torch.Tensor
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block_table: torch.Tensor
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slot_mapping: torch.Tensor
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# For cascade attention.
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use_cascade: bool
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common_prefix_len: int
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cu_prefix_query_lens: Optional[torch.Tensor]
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prefix_kv_lens: Optional[torch.Tensor]
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suffix_kv_lens: Optional[torch.Tensor]
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# Optional aot scheduling
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scheduler_metadata: Optional[torch.Tensor] = None
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prefix_scheduler_metadata: Optional[torch.Tensor] = None
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class RocmAttentionMetadataBuilder(
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AttentionMetadataBuilder[RocmAttentionMetadata]):
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cudagraph_support: ClassVar[AttentionCGSupport] = AttentionCGSupport.ALWAYS
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def __init__(self, kv_cache_spec: AttentionSpec, layer_names: list[str],
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vllm_config: VllmConfig, device: torch.device):
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super().__init__(kv_cache_spec, layer_names, vllm_config, device)
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self.block_size = kv_cache_spec.block_size
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model_config = vllm_config.model_config
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self.num_heads_q = model_config.get_num_attention_heads(
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vllm_config.parallel_config)
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self.num_heads_kv = model_config.get_num_kv_heads(
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vllm_config.parallel_config)
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self.headdim = model_config.get_head_size()
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def build_for_cudagraph_capture(
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self, common_attn_metadata: CommonAttentionMetadata
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) -> RocmAttentionMetadata:
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attn_metadata = self.build(0, common_attn_metadata)
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# When doing full graph capture, setting seq_lens to
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# max_model_len will cause graph capture to be extremely
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# slow, so here we set it to 1.
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attn_metadata.seq_lens.fill_(1)
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return attn_metadata
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def build(self,
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common_prefix_len: int,
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common_attn_metadata: CommonAttentionMetadata,
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fast_build: bool = False) -> RocmAttentionMetadata:
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num_actual_tokens = common_attn_metadata.num_actual_tokens
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max_query_len = common_attn_metadata.max_query_len
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max_seq_len = common_attn_metadata.max_seq_len
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query_start_loc = common_attn_metadata.query_start_loc
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seq_lens = common_attn_metadata.seq_lens
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block_table_tensor = common_attn_metadata.block_table_tensor
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slot_mapping = common_attn_metadata.slot_mapping
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use_cascade = common_prefix_len > 0
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if use_cascade:
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cu_prefix_query_lens = torch.tensor([0, num_actual_tokens],
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dtype=torch.int32,
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device=self.device)
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prefix_kv_lens = torch.tensor([common_prefix_len],
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dtype=torch.int32,
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device=self.device)
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suffix_kv_lens = (common_attn_metadata.seq_lens_cpu -
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common_prefix_len)
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suffix_kv_lens = suffix_kv_lens.to(self.device)
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else:
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cu_prefix_query_lens = None
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prefix_kv_lens = None
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suffix_kv_lens = None
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prefix_scheduler_metadata = None
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attn_metadata = RocmAttentionMetadata(
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num_actual_tokens=num_actual_tokens,
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max_query_len=max_query_len,
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query_start_loc=query_start_loc,
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max_seq_len=max_seq_len,
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seq_lens=seq_lens,
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block_table=block_table_tensor,
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slot_mapping=slot_mapping,
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use_cascade=use_cascade,
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common_prefix_len=common_prefix_len,
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cu_prefix_query_lens=cu_prefix_query_lens,
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prefix_kv_lens=prefix_kv_lens,
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suffix_kv_lens=suffix_kv_lens,
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prefix_scheduler_metadata=prefix_scheduler_metadata,
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)
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return attn_metadata
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class RocmAttentionBackend(AttentionBackend):
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accept_output_buffer: bool = True
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@classmethod
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def get_supported_dtypes(cls) -> list[torch.dtype]:
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return [torch.float16, torch.bfloat16]
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@classmethod
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def get_supported_head_sizes(cls) -> list[int]:
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return [32, 64, 96, 128, 160, 192, 224, 256]
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@classmethod
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def validate_head_size(cls, head_size: int) -> None:
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supported_head_sizes = cls.get_supported_head_sizes()
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if head_size not in supported_head_sizes:
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attn_type = cls.__name__.removesuffix("Backend")
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raise ValueError(
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f"Head size {head_size} is not supported by {attn_type}. "
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f"Supported head sizes are: {supported_head_sizes}. "
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"Set VLLM_ATTENTION_BACKEND=FLEX_ATTENTION to use "
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"FlexAttention backend which supports all head sizes.")
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@staticmethod
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def get_name() -> str:
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return "ROCM_ATTN_VLLM_V1"
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@staticmethod
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def get_impl_cls() -> type["RocmAttentionImpl"]:
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return RocmAttentionImpl
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@staticmethod
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def get_metadata_cls() -> type["AttentionMetadata"]:
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return RocmAttentionMetadata
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@staticmethod
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def get_kv_cache_shape(
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num_blocks: int,
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block_size: int,
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num_kv_heads: int,
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head_size: int,
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) -> tuple[int, ...]:
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if block_size % 16 != 0:
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raise ValueError("Block size must be a multiple of 16.")
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return (2, num_blocks, block_size, num_kv_heads, head_size)
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@staticmethod
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def use_cascade_attention(*args, **kwargs) -> bool:
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return False
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@staticmethod
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def get_builder_cls() -> type["RocmAttentionMetadataBuilder"]:
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return RocmAttentionMetadataBuilder
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@cache
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def use_aiter_unified_attention() -> bool:
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"""Check if aiter unified attention should be used."""
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# VLLM_ROCM_USE_AITER_MHA needs to set to 0 as well as it is set
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# to 1 as default
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return envs.VLLM_ROCM_USE_AITER \
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and envs.VLLM_USE_AITER_UNIFIED_ATTENTION
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class RocmAttentionImpl(AttentionImpl):
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def fused_output_quant_supported(self, quant_key: QuantKey):
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return quant_key == kFp8StaticTensorSym
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def __init__(
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self,
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num_heads: int,
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head_size: int,
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scale: float,
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num_kv_heads: int,
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alibi_slopes: Optional[list[float]],
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sliding_window: Optional[int],
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kv_cache_dtype: str,
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logits_soft_cap: Optional[float] = None,
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attn_type: AttentionType = AttentionType.DECODER,
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kv_sharing_target_layer_name: Optional[int] = None,
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sinks: Optional[torch.Tensor] = None,
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) -> None:
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self.num_heads = num_heads
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self.head_size = head_size
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self.scale = float(scale)
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self.num_kv_heads = num_kv_heads
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if alibi_slopes is not None:
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alibi_slopes = torch.tensor(alibi_slopes, dtype=torch.float32)
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self.alibi_slopes = alibi_slopes
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if sliding_window is None:
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self.sliding_window = (-1, -1)
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else:
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self.sliding_window = (sliding_window - 1, 0)
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self.kv_cache_dtype = kv_cache_dtype
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if logits_soft_cap is None:
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# In flash-attn, setting logits_soft_cap as 0 means no soft cap.
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logits_soft_cap = 0
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self.logits_soft_cap = logits_soft_cap
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self.kv_sharing_target_layer_name = kv_sharing_target_layer_name
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self.num_queries_per_kv = self.num_heads // self.num_kv_heads
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RocmAttentionBackend.validate_head_size(head_size)
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if attn_type != AttentionType.DECODER:
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raise NotImplementedError("Encoder self-attention and "
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"encoder/decoder cross-attention "
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"are not implemented for "
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"RocmAttentionImpl")
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self.fp8_dtype = current_platform.fp8_dtype()
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self.force_prefill_decode_attn = \
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envs.VLLM_V1_USE_PREFILL_DECODE_ATTENTION
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if not self.force_prefill_decode_attn:
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# If not using prefill decode attention, we use the Triton
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# unified attention implementation.
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if use_aiter_unified_attention():
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logger.info_once(
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"Using aiter unified attention for RocmAttentionImpl")
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from aiter.ops.triton.unified_attention import (
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unified_attention)
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self.unified_attention = unified_attention
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else:
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logger.info_once(
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"Using vllm unified attention for RocmAttentionImpl")
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from vllm.attention.ops.triton_unified_attention import (
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unified_attention)
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self.unified_attention = unified_attention
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self.sinks = sinks
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if sinks is not None:
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assert sinks.shape[0] == num_heads, (
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"Sinks must have the same number of heads as the number of "
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f"heads in the layer. Sinks shape: {sinks.shape}, "
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f"num_heads: {num_heads}.")
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def forward(
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self,
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layer: torch.nn.Module,
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query: torch.Tensor,
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key: torch.Tensor,
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value: torch.Tensor,
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kv_cache: torch.Tensor,
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attn_metadata: FlashAttentionMetadata,
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output: Optional[torch.Tensor] = None,
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output_scale: Optional[torch.Tensor] = None,
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output_block_scale: Optional[torch.Tensor] = None,
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) -> torch.Tensor:
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"""Forward pass with FlashAttention.
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Args:
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query: shape = [num_tokens, num_heads, head_size]
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key: shape = [num_tokens, num_kv_heads, head_size]
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value: shape = [num_tokens, num_kv_heads, head_size]
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kv_cache: shape =
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[2, num_blocks, block_size, num_kv_heads, head_size]
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attn_metadata: Metadata for attention.
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Returns:
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shape = [num_tokens, num_heads * head_size]
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"""
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assert output is not None, "Output tensor must be provided."
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if output_block_scale is not None:
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raise NotImplementedError(
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"fused block_scale output quantization is not yet supported"
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" for RocmAttentionImpl")
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if attn_metadata is None:
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# Profiling run.
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return output
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assert attn_metadata.use_cascade is False
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# IMPORTANT!
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# NOTE(woosuk): With piece-wise CUDA graphs, this method is executed in
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# eager-mode PyTorch. Thus, we need to be careful about any CPU overhead
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# in this method. For example, `view` and `slice` (or `[:n]`) operations
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# are surprisingly slow even in the case they do not invoke any GPU ops.
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# Minimize the PyTorch ops in this method as much as possible.
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# Whenever making a change in this method, please benchmark the
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# performance to make sure it does not introduce any overhead.
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use_prefill_decode_attn = self.force_prefill_decode_attn
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num_actual_tokens = attn_metadata.num_actual_tokens
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if use_prefill_decode_attn:
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key_cache, value_cache = PagedAttention.split_kv_cache(
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kv_cache, self.num_kv_heads, self.head_size)
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else:
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key_cache, value_cache = kv_cache.unbind(0)
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if self.kv_sharing_target_layer_name is None:
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# Reshape the input keys and values and store them in the cache.
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# Skip this if sharing KV cache with an earlier attention layer.
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if use_prefill_decode_attn:
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PagedAttention.write_to_paged_cache(
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key,
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value,
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key_cache,
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value_cache,
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attn_metadata.slot_mapping,
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self.kv_cache_dtype,
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layer._k_scale,
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layer._v_scale,
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)
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else:
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ops.reshape_and_cache_flash(
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key,
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value,
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key_cache,
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value_cache,
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attn_metadata.slot_mapping,
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self.kv_cache_dtype,
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layer._k_scale,
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layer._v_scale,
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)
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if self.kv_cache_dtype.startswith("fp8"):
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key_cache = key_cache.view(self.fp8_dtype)
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value_cache = value_cache.view(self.fp8_dtype)
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num_tokens, num_heads, head_size = query.shape
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assert layer._q_scale_float == 1.0, \
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"A non 1.0 q_scale is not currently supported."
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if current_platform.is_cuda():
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# Skip Q quantization on ROCm and XPU, enable this on cuda
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# only, since dequantizing back to f32 in the attention kernel
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# is not supported.
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query, _ = ops.scaled_fp8_quant(
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query.reshape(
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(num_tokens, num_heads * head_size)).contiguous(),
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layer._q_scale)
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query = query.reshape((num_tokens, num_heads, head_size))
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cu_seqlens_q = attn_metadata.query_start_loc
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seqused_k = attn_metadata.seq_lens
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max_seqlen_q = attn_metadata.max_query_len
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max_seqlen_k = attn_metadata.max_seq_len
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block_table = attn_metadata.block_table
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if use_prefill_decode_attn:
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# Compute attention and update output up to `num_actual_tokens`.
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chunked_prefill_paged_decode(
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query=query[:num_actual_tokens],
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key=key[:num_actual_tokens],
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value=value[:num_actual_tokens],
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output=output[:num_actual_tokens],
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kv_cache_dtype=self.kv_cache_dtype,
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key_cache=key_cache,
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value_cache=value_cache,
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block_table=block_table,
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query_start_loc=cu_seqlens_q,
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seq_lens=seqused_k,
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max_seq_len=max_seqlen_k,
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max_query_len=max_seqlen_q,
|
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k_scale=layer._k_scale,
|
||||
v_scale=layer._v_scale,
|
||||
alibi_slopes=self.alibi_slopes,
|
||||
sliding_window=self.sliding_window[0],
|
||||
sm_scale=self.scale,
|
||||
output_scale=output_scale,
|
||||
sinks=self.sinks,
|
||||
)
|
||||
|
||||
else:
|
||||
descale_shape = (cu_seqlens_q.shape[0] - 1, key.shape[1])
|
||||
|
||||
self.unified_attention(
|
||||
q=query[:num_actual_tokens],
|
||||
k=key_cache,
|
||||
v=value_cache,
|
||||
out=output[:num_actual_tokens],
|
||||
cu_seqlens_q=cu_seqlens_q,
|
||||
max_seqlen_q=max_seqlen_q,
|
||||
seqused_k=seqused_k,
|
||||
max_seqlen_k=max_seqlen_k,
|
||||
softmax_scale=self.scale,
|
||||
causal=True,
|
||||
alibi_slopes=self.alibi_slopes,
|
||||
window_size=self.sliding_window,
|
||||
block_table=block_table,
|
||||
softcap=self.logits_soft_cap,
|
||||
q_descale=None, # Not supported
|
||||
k_descale=layer._k_scale.expand(descale_shape),
|
||||
v_descale=layer._v_scale.expand(descale_shape),
|
||||
sinks=self.sinks,
|
||||
output_scale=output_scale)
|
||||
|
||||
return output
|
||||
@ -1,24 +1,19 @@
|
||||
# SPDX-License-Identifier: Apache-2.0
|
||||
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
|
||||
"""Attention layer with PagedAttention and Triton prefix prefill."""
|
||||
"""High-Performance Triton-only Attention layer."""
|
||||
from dataclasses import dataclass
|
||||
from functools import cache
|
||||
from typing import ClassVar, Optional
|
||||
|
||||
import torch
|
||||
|
||||
from vllm import envs
|
||||
from vllm.attention.backends.abstract import (AttentionBackend, AttentionImpl,
|
||||
AttentionMetadata, AttentionType)
|
||||
from vllm.attention.ops.chunked_prefill_paged_decode import (
|
||||
chunked_prefill_paged_decode)
|
||||
from vllm.attention.ops.paged_attn import PagedAttention
|
||||
from vllm.attention.ops.triton_unified_attention import unified_attention
|
||||
from vllm.config import VllmConfig
|
||||
from vllm.logger import init_logger
|
||||
from vllm.model_executor.layers.quantization.utils.quant_utils import (
|
||||
QuantKey, kFp8StaticTensorSym)
|
||||
from vllm.platforms import current_platform
|
||||
from vllm.v1.attention.backends.flash_attn import FlashAttentionMetadata
|
||||
from vllm.v1.attention.backends.utils import (AttentionCGSupport,
|
||||
AttentionMetadataBuilder,
|
||||
CommonAttentionMetadata)
|
||||
@ -144,20 +139,15 @@ class TritonAttentionBackend(AttentionBackend):
|
||||
|
||||
@classmethod
|
||||
def get_supported_dtypes(cls) -> list[torch.dtype]:
|
||||
return [torch.float16, torch.bfloat16]
|
||||
|
||||
@classmethod
|
||||
def get_supported_head_sizes(cls) -> list[int]:
|
||||
return [32, 64, 96, 128, 160, 192, 224, 256]
|
||||
return [torch.float16, torch.bfloat16, torch.float32]
|
||||
|
||||
@classmethod
|
||||
def validate_head_size(cls, head_size: int) -> None:
|
||||
supported_head_sizes = cls.get_supported_head_sizes()
|
||||
if head_size not in supported_head_sizes:
|
||||
attn_type = cls.__name__.removesuffix("Backend")
|
||||
# Triton Attention supports any head size above 32
|
||||
if head_size < 32:
|
||||
raise ValueError(
|
||||
f"Head size {head_size} is not supported by {attn_type}. "
|
||||
f"Supported head sizes are: {supported_head_sizes}. "
|
||||
f"Head size {head_size} is not supported by TritonAttention."
|
||||
f"Head sizes need to be larger or equal 32 for this backend. "
|
||||
"Set VLLM_ATTENTION_BACKEND=FLEX_ATTENTION to use "
|
||||
"FlexAttention backend which supports all head sizes.")
|
||||
|
||||
@ -182,7 +172,7 @@ class TritonAttentionBackend(AttentionBackend):
|
||||
) -> tuple[int, ...]:
|
||||
if block_size % 16 != 0:
|
||||
raise ValueError("Block size must be a multiple of 16.")
|
||||
return (2, num_blocks, block_size, num_kv_heads, head_size)
|
||||
return (num_blocks, 2, block_size, num_kv_heads, head_size)
|
||||
|
||||
@staticmethod
|
||||
def use_cascade_attention(*args, **kwargs) -> bool:
|
||||
@ -193,15 +183,6 @@ class TritonAttentionBackend(AttentionBackend):
|
||||
return TritonAttentionMetadataBuilder
|
||||
|
||||
|
||||
@cache
|
||||
def use_aiter_unified_attention() -> bool:
|
||||
"""Check if aiter unified attention should be used."""
|
||||
# VLLM_ROCM_USE_AITER_MHA needs to set to 0 as well as it is set
|
||||
# to 1 as default
|
||||
return envs.VLLM_ROCM_USE_AITER \
|
||||
and envs.VLLM_USE_AITER_UNIFIED_ATTENTION
|
||||
|
||||
|
||||
class TritonAttentionImpl(AttentionImpl):
|
||||
|
||||
def fused_output_quant_supported(self, quant_key: QuantKey):
|
||||
@ -250,24 +231,6 @@ class TritonAttentionImpl(AttentionImpl):
|
||||
"TritonAttentionImpl")
|
||||
|
||||
self.fp8_dtype = current_platform.fp8_dtype()
|
||||
self.force_prefill_decode_attn = \
|
||||
envs.VLLM_V1_USE_PREFILL_DECODE_ATTENTION
|
||||
|
||||
if not self.force_prefill_decode_attn:
|
||||
# If not using prefill decode attention, we use the Triton
|
||||
# unified attention implementation.
|
||||
if use_aiter_unified_attention():
|
||||
logger.info_once(
|
||||
"Using aiter unified attention for TritonAttentionImpl")
|
||||
from aiter.ops.triton.unified_attention import (
|
||||
unified_attention)
|
||||
self.unified_attention = unified_attention
|
||||
else:
|
||||
logger.info_once(
|
||||
"Using vllm unified attention for TritonAttentionImpl")
|
||||
from vllm.attention.ops.triton_unified_attention import (
|
||||
unified_attention)
|
||||
self.unified_attention = unified_attention
|
||||
|
||||
self.sinks = sinks
|
||||
if sinks is not None:
|
||||
@ -283,19 +246,19 @@ class TritonAttentionImpl(AttentionImpl):
|
||||
key: torch.Tensor,
|
||||
value: torch.Tensor,
|
||||
kv_cache: torch.Tensor,
|
||||
attn_metadata: FlashAttentionMetadata,
|
||||
attn_metadata: TritonAttentionMetadata,
|
||||
output: Optional[torch.Tensor] = None,
|
||||
output_scale: Optional[torch.Tensor] = None,
|
||||
output_block_scale: Optional[torch.Tensor] = None,
|
||||
) -> torch.Tensor:
|
||||
"""Forward pass with FlashAttention.
|
||||
"""Forward pass with Paged Attention impl. in Triton.
|
||||
|
||||
Args:
|
||||
query: shape = [num_tokens, num_heads, head_size]
|
||||
key: shape = [num_tokens, num_kv_heads, head_size]
|
||||
value: shape = [num_tokens, num_kv_heads, head_size]
|
||||
kv_cache: shape =
|
||||
[2, num_blocks, block_size, num_kv_heads, head_size]
|
||||
[num_blocks, 2, block_size, num_kv_heads, head_size]
|
||||
attn_metadata: Metadata for attention.
|
||||
Returns:
|
||||
shape = [num_tokens, num_heads * head_size]
|
||||
@ -322,40 +285,22 @@ class TritonAttentionImpl(AttentionImpl):
|
||||
# Whenever making a change in this method, please benchmark the
|
||||
# performance to make sure it does not introduce any overhead.
|
||||
|
||||
use_prefill_decode_attn = self.force_prefill_decode_attn
|
||||
num_actual_tokens = attn_metadata.num_actual_tokens
|
||||
|
||||
if use_prefill_decode_attn:
|
||||
key_cache, value_cache = PagedAttention.split_kv_cache(
|
||||
kv_cache, self.num_kv_heads, self.head_size)
|
||||
else:
|
||||
key_cache, value_cache = kv_cache.unbind(0)
|
||||
key_cache, value_cache = kv_cache.unbind(1)
|
||||
|
||||
if self.kv_sharing_target_layer_name is None:
|
||||
# Reshape the input keys and values and store them in the cache.
|
||||
# Skip this if sharing KV cache with an earlier attention layer.
|
||||
if use_prefill_decode_attn:
|
||||
PagedAttention.write_to_paged_cache(
|
||||
key,
|
||||
value,
|
||||
key_cache,
|
||||
value_cache,
|
||||
attn_metadata.slot_mapping,
|
||||
self.kv_cache_dtype,
|
||||
layer._k_scale,
|
||||
layer._v_scale,
|
||||
)
|
||||
else:
|
||||
ops.reshape_and_cache_flash(
|
||||
key,
|
||||
value,
|
||||
key_cache,
|
||||
value_cache,
|
||||
attn_metadata.slot_mapping,
|
||||
self.kv_cache_dtype,
|
||||
layer._k_scale,
|
||||
layer._v_scale,
|
||||
)
|
||||
ops.reshape_and_cache_flash(
|
||||
key,
|
||||
value,
|
||||
key_cache,
|
||||
value_cache,
|
||||
attn_metadata.slot_mapping,
|
||||
self.kv_cache_dtype,
|
||||
layer._k_scale,
|
||||
layer._v_scale,
|
||||
)
|
||||
|
||||
if self.kv_cache_dtype.startswith("fp8"):
|
||||
key_cache = key_cache.view(self.fp8_dtype)
|
||||
@ -379,52 +324,28 @@ class TritonAttentionImpl(AttentionImpl):
|
||||
max_seqlen_k = attn_metadata.max_seq_len
|
||||
block_table = attn_metadata.block_table
|
||||
|
||||
if use_prefill_decode_attn:
|
||||
# Compute attention and update output up to `num_actual_tokens`.
|
||||
chunked_prefill_paged_decode(
|
||||
query=query[:num_actual_tokens],
|
||||
key=key[:num_actual_tokens],
|
||||
value=value[:num_actual_tokens],
|
||||
output=output[:num_actual_tokens],
|
||||
kv_cache_dtype=self.kv_cache_dtype,
|
||||
key_cache=key_cache,
|
||||
value_cache=value_cache,
|
||||
block_table=block_table,
|
||||
query_start_loc=cu_seqlens_q,
|
||||
seq_lens=seqused_k,
|
||||
max_seq_len=max_seqlen_k,
|
||||
max_query_len=max_seqlen_q,
|
||||
k_scale=layer._k_scale,
|
||||
v_scale=layer._v_scale,
|
||||
alibi_slopes=self.alibi_slopes,
|
||||
sliding_window=self.sliding_window[0],
|
||||
sm_scale=self.scale,
|
||||
output_scale=output_scale,
|
||||
sinks=self.sinks,
|
||||
)
|
||||
descale_shape = (cu_seqlens_q.shape[0] - 1, key.shape[1])
|
||||
|
||||
else:
|
||||
descale_shape = (cu_seqlens_q.shape[0] - 1, key.shape[1])
|
||||
|
||||
self.unified_attention(
|
||||
q=query[:num_actual_tokens],
|
||||
k=key_cache,
|
||||
v=value_cache,
|
||||
out=output[:num_actual_tokens],
|
||||
cu_seqlens_q=cu_seqlens_q,
|
||||
max_seqlen_q=max_seqlen_q,
|
||||
seqused_k=seqused_k,
|
||||
max_seqlen_k=max_seqlen_k,
|
||||
softmax_scale=self.scale,
|
||||
causal=True,
|
||||
alibi_slopes=self.alibi_slopes,
|
||||
window_size=self.sliding_window,
|
||||
block_table=block_table,
|
||||
softcap=self.logits_soft_cap,
|
||||
q_descale=None, # Not supported
|
||||
k_descale=layer._k_scale.expand(descale_shape),
|
||||
v_descale=layer._v_scale.expand(descale_shape),
|
||||
sinks=self.sinks,
|
||||
output_scale=output_scale)
|
||||
unified_attention(
|
||||
q=query[:num_actual_tokens],
|
||||
k=key_cache,
|
||||
v=value_cache,
|
||||
out=output[:num_actual_tokens],
|
||||
cu_seqlens_q=cu_seqlens_q,
|
||||
max_seqlen_q=max_seqlen_q,
|
||||
seqused_k=seqused_k,
|
||||
max_seqlen_k=max_seqlen_k,
|
||||
softmax_scale=self.scale,
|
||||
causal=True,
|
||||
alibi_slopes=self.alibi_slopes,
|
||||
window_size=self.sliding_window,
|
||||
block_table=block_table,
|
||||
softcap=self.logits_soft_cap,
|
||||
q_descale=None, # Not supported
|
||||
k_descale=layer._k_scale.expand(descale_shape),
|
||||
v_descale=layer._v_scale.expand(descale_shape),
|
||||
sinks=self.sinks,
|
||||
output_scale=output_scale,
|
||||
)
|
||||
|
||||
return output
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user