Files
project_6/ex_engine/csrc/ilu_layer_attention.cpp
project6-dev f4e2264a83 ref(EX): import upstream ILU kernels + xllm MoE CUDA sources into ex_engine
Copied from upstream_ref (NOT rewritten — exact upstream code):

ixformer C++ API (the authoritative header):
  include/ixformer.h — ixformer::infer namespace: topk_softmax,
    moe_compute_token_index_api, moe_w16a16_group_gemm, moe_expand_input,
    moe_output_reduce_sum, silu_and_mul, rms_norm, xllm_paged_attention, etc.
  include/ilu_ops_api.h — xllm::kernel::ilu namespace: moe_active_topk,
    moe_gen_idx, moe_expand_input, group_gemm, moe_combine_result,
    batch_prefill, batch_decode, rms_norm, matmul, act_and_mul, etc.

ILU kernel wrappers (call ixformer::infer directly):
  csrc/ilu_kernel_fused_moe.cpp — topk routing + gen_idx + expand + combine
  csrc/ilu_kernel_group_gemm.cpp — batched expert GEMM
  csrc/ilu_kernel_{activation,norm,rope,matmul,attention}.cpp

ILU layer implementations (full pipeline):
  csrc/ilu_layer_fused_moe.{cpp,h} — 797 lines, the complete MoE pipeline
    that competitor 168 ran as corex_moe.py
  csrc/ilu_layer_attention.{cpp,h} — prefill/decode attention dispatch

CUDA MoE kernels (from xllm + ds_vllm):
  csrc/moe/moe_topk_softmax_kernels.cuh — CUB BlockReduce + warp topk
  csrc/moe/moe_topk_sigmoid_kernels.cuh — sigmoid scoring variant
  csrc/moe/moe_topk.cuh + moe_fused_topk.cu — entry points
  csrc/moe/moeTopKFuncs.cuh — TRT-LLM derived vllm-compatible topk
  csrc/moe/moe_ops.h + moe_align_sum_kernels.cu — alignment kernels

Common layer headers:
  csrc/common_fused_moe{,_base}.h + common_moe_fused_topk.{cpp,h}
2026-08-10 03:59:45 +00:00

190 lines
7.9 KiB
C++

/* Copyright 2025 The xLLM Authors. All Rights Reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
https://github.com/jd-opensource/xllm/blob/main/LICENSE
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================*/
#include "attention.h"
#include "kernels/ilu/ilu_ops_api.h"
#include "kernels/ops_api.h"
namespace xllm {
namespace layer {
AttentionImpl::AttentionImpl(int64_t num_heads,
int64_t head_size,
float scale,
int64_t num_kv_heads,
int64_t sliding_window)
: num_heads_(num_heads),
head_size_(head_size),
scale_(scale),
num_kv_heads_(num_kv_heads),
v_head_dim_(head_size),
use_fused_mla_qkv_(false),
enable_lighting_indexer_(false),
enable_mla_(false),
sliding_window_(sliding_window) {
if (sliding_window_ > -1) {
sliding_window_ = sliding_window_ - 1;
}
}
AttentionImpl::AttentionImpl(int64_t num_heads,
int64_t head_size,
int64_t num_kv_heads,
int64_t v_head_dim,
int64_t sliding_window,
float scale,
bool use_fused_mla_qkv,
bool enable_lighting_indexer,
bool enable_mla)
: num_heads_(num_heads),
head_size_(head_size),
scale_(scale),
num_kv_heads_(num_kv_heads),
v_head_dim_(v_head_dim),
use_fused_mla_qkv_(use_fused_mla_qkv),
enable_lighting_indexer_(enable_lighting_indexer),
enable_mla_(enable_mla),
sliding_window_(sliding_window) {
if (sliding_window_ > -1) {
sliding_window_ = sliding_window_ - 1;
}
}
std::tuple<torch::Tensor, std::optional<torch::Tensor>> AttentionImpl::forward(
const AttentionMetadata& attn_metadata,
torch::Tensor& query,
torch::Tensor& key,
torch::Tensor& value,
KVCache& kv_cache) {
std::optional<torch::Tensor> output_lse = std::nullopt;
torch::Tensor output;
if (enable_mla_) {
output = torch::empty({query.size(0), num_heads_ * v_head_dim_},
query.options());
} else {
output = torch::empty_like(query);
}
if (attn_metadata.is_dummy) {
return std::make_tuple(output, output_lse);
}
bool only_prefill =
attn_metadata.is_prefill || attn_metadata.is_chunked_prefill;
int64_t num_kv_heads = (enable_mla_ && !only_prefill) ? 1 : num_kv_heads_;
torch::Tensor k_cache = kv_cache.get_k_cache();
std::optional<torch::Tensor> v_cache;
std::optional<torch::Tensor> v;
if (!enable_mla_) {
v = value.view({-1, num_kv_heads, head_size_});
v_cache = kv_cache.get_v_cache();
}
bool skip_process_cache = enable_mla_ && (only_prefill || use_fused_mla_qkv_);
if (!skip_process_cache) {
xllm::kernel::ReshapePagedCacheParams reshape_paged_cache_params;
reshape_paged_cache_params.key = key.view({-1, num_kv_heads, head_size_});
reshape_paged_cache_params.value = v;
reshape_paged_cache_params.k_cache = k_cache;
reshape_paged_cache_params.v_cache = v_cache;
reshape_paged_cache_params.slot_mapping = attn_metadata.slot_mapping;
xllm::kernel::reshape_paged_cache(reshape_paged_cache_params);
}
if (enable_lighting_indexer_ || !only_prefill) {
decoder_forward(query, output, k_cache, v_cache, attn_metadata);
} else {
prefill_forward(query, key, value, output, k_cache, v_cache, attn_metadata);
}
int64_t head_size = enable_mla_ ? v_head_dim_ : head_size_;
output = output.view({-1, num_heads_ * head_size});
return {output, output_lse};
}
void AttentionImpl::prefill_forward(torch::Tensor& query,
torch::Tensor& key,
torch::Tensor& value,
torch::Tensor& output,
const torch::Tensor& k_cache,
const std::optional<torch::Tensor>& v_cache,
const AttentionMetadata& attn_metadata) {
int64_t head_size_v = enable_mla_ ? v_head_dim_ : head_size_;
std::optional<torch::Tensor> output_lse = std::nullopt;
query = query.view({-1, num_heads_, head_size_});
output = output.view({-1, num_heads_, head_size_v});
// torch::Tensor k_cache_ = k_cache;
// torch::Tensor v_cache_ = v_cache.value();
xllm::kernel::ilu::batch_prefill(query,
k_cache,
v_cache,
output,
output_lse,
attn_metadata.q_cu_seq_lens,
attn_metadata.kv_cu_seq_lens,
/*alibi_slope=*/std::nullopt,
/*attn_bias=*/std::nullopt,
/*q_quant_scale=*/std::nullopt,
/*k_quant_scale=*/std::nullopt,
/*v_quant_scale=*/std::nullopt,
attn_metadata.block_table,
attn_metadata.max_query_len,
attn_metadata.max_seq_len,
scale_,
attn_metadata.is_causal,
sliding_window_,
/*window_size_right=*/-1,
attn_metadata.compute_dtype,
/*return_lse=*/false);
}
void AttentionImpl::decoder_forward(torch::Tensor& query,
torch::Tensor& output,
const torch::Tensor& k_cache,
const std::optional<torch::Tensor>& v_cache,
const AttentionMetadata& attn_metadata) {
int64_t head_size_v = enable_mla_ ? v_head_dim_ : head_size_;
query = query.view({-1, 1, num_heads_, head_size_});
output = output.view({-1, 1, num_heads_, head_size_v});
std::optional<torch::Tensor> output_lse = std::nullopt;
int64_t block_aligned_max_seq_len =
attn_metadata.block_table.size(-1) * k_cache.size(2);
xllm::kernel::ilu::batch_decode(query,
k_cache,
output,
attn_metadata.block_table,
attn_metadata.kv_seq_lens,
v_cache,
output_lse,
/*q_quant_scale=*/std::nullopt,
/*k_quant_scale=*/std::nullopt,
/*v_quant_scale=*/std::nullopt,
/*out_quant_scale=*/std::nullopt,
/*alibi_slope=*/std::nullopt,
attn_metadata.attn_mask,
attn_metadata.compute_dtype,
block_aligned_max_seq_len,
sliding_window_,
/*window_size_right=*/-1,
scale_,
/*return_lse=*/false,
attn_metadata.is_causal,
/*kv_cache_quant_bit_size=*/-1);
}
} // namespace layer
} // namespace xllm