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DeepGEMM/csrc/jit_kernels/impls/smxx_fp8_fp4_mqa_logits.hpp
Chenggang Zhao 7f2a703ed5 [Public release 26/04] Introducing Mega MoE, FP4 Indexer and other features/fixes (#304)
* Merge with private repo

* Update README

* Update README

* Update README

* Add PyTorch requirements

* Fix sync scopes for MQA logits (#256)

* Update README
2026-04-17 09:45:14 +08:00

329 lines
14 KiB
C++

#pragma once
#include "../../jit/compiler.hpp"
#include "../../jit/device_runtime.hpp"
#include "../../jit/kernel_runtime.hpp"
#include "../heuristics/sm90.hpp"
#include "../heuristics/sm100.hpp"
#include "runtime_utils.hpp"
namespace deep_gemm {
class SMXXFP8MQALogitsRuntime final: public LaunchRuntime<SMXXFP8MQALogitsRuntime> {
public:
struct Args {
int seq_len;
int seq_len_kv;
int max_seqlen_k;
int stride_logits;
int num_heads, head_dim;
bool is_compressed_logits;
int num_q_stages;
int num_kv_stages;
int block_q;
int block_kv;
int* cu_seq_len_k_start;
int* cu_seq_len_k_end;
void* logits;
CUtensorMap tensor_map_q;
CUtensorMap tensor_map_kv;
CUtensorMap tensor_map_kv_scales;
CUtensorMap tensor_map_weights;
at::ScalarType logits_dtype;
int num_specialized_threads;
int num_math_threads;
LaunchArgs launch_args;
};
static std::string generate_impl(const Args& args) {
// TODO: optimize performance by tuning args
// Block sizes are fixed in this kernel
DG_HOST_ASSERT(128 % args.num_heads == 0);
const auto arch = device_runtime->get_arch(true);
return fmt::format(R"(
#include <deep_gemm/impls/sm{}_fp8_mqa_logits.cuh>
using namespace deep_gemm;
static void __instantiate_kernel() {{
auto ptr = reinterpret_cast<void*>(&sm{}_fp8_mqa_logits<
{}, {},
{},
{}, {},
{}, {},
{},
{}, {},
{}
>);
}};
)", arch, arch,
args.num_heads, args.head_dim,
args.is_compressed_logits,
args.block_q, args.block_kv,
args.num_q_stages, args.num_kv_stages,
args.launch_args.grid_dim.first,
args.num_specialized_threads, args.num_math_threads,
to_string(args.logits_dtype));
}
static void launch_impl(const KernelHandle& kernel, const LaunchConfigHandle& config, Args args) {
DG_CUDA_UNIFIED_CHECK(launch_kernel(kernel, config,
args.seq_len, args.seq_len_kv,
args.max_seqlen_k, args.stride_logits,
args.cu_seq_len_k_start, args.cu_seq_len_k_end,
args.logits,
args.tensor_map_q, args.tensor_map_kv,
args.tensor_map_kv_scales, args.tensor_map_weights
));
}
};
static void smxx_fp8_mqa_logits(const torch::Tensor& q,
const torch::Tensor& kv, const torch::Tensor& kv_scales,
const torch::Tensor& weights,
const torch::Tensor& cu_seq_len_k_start,
const torch::Tensor& cu_seq_len_k_end,
const torch::Tensor& logits,
const at::ScalarType& logits_dtype,
const int& seq_len, const int& seq_len_kv,
const int& max_seqlen_k, const int& stride_logits,
const int& num_heads, const int& head_dim,
const int& block_q, const int& block_kv) {
constexpr int num_specialized_threads = 128;
constexpr int num_q_stages = 3, num_kv_stages = 3;
const int num_math_threads = (device_runtime->get_arch_major() == 10 ? 256 : 512);
// Use compressed logits format when max_seqlen_k is specified
const bool is_compressed_logits = (max_seqlen_k > 0);
// Construct TMAs
DG_HOST_ASSERT(head_dim == 32 or head_dim == 64 or head_dim == 128);
const auto tensor_map_q = make_tma_2d_desc(q, head_dim, seq_len * num_heads,
head_dim, block_q * num_heads, head_dim, head_dim);
const auto tensor_map_kv = make_tma_2d_desc(kv, head_dim, seq_len_kv,
head_dim, block_kv, head_dim, head_dim);
// According to the driver API, the minimal alignment is 256 bytes
// So it is safe for us to do a 16-byte OOB
const auto tensor_map_kv_scales = make_tma_2d_desc(kv_scales,
get_tma_aligned_size(seq_len_kv, static_cast<int>(kv_scales.element_size())),
1, block_kv, 1, 0, 0);
const auto tensor_map_weights = make_tma_2d_desc(weights, num_heads, seq_len,
num_heads, block_q, num_heads, 0);
// Calculate shared memory size
int smem_size = 0;
const int smem_q_size_per_stage = block_q * num_heads * head_dim * static_cast<int>(q.element_size());
const int smem_weight_size_per_stage = block_q * num_heads * static_cast<int>(weights.element_size());
const int smem_kv_size_per_stage = block_kv * head_dim * static_cast<int>(kv.element_size());
const int kv_scale_size_per_stage = block_kv * static_cast<int>(kv_scales.element_size());
smem_size += num_q_stages * smem_q_size_per_stage;
smem_size += num_kv_stages * smem_kv_size_per_stage;
smem_size += num_q_stages * smem_weight_size_per_stage;
smem_size += num_kv_stages * kv_scale_size_per_stage;
smem_size += (num_q_stages * 2 + num_kv_stages * 2 + (num_math_threads / 128) * 2) * 8;
smem_size += 4;
DG_HOST_ASSERT(smem_size <= SM90ArchSpec::smem_capacity);
DG_HOST_ASSERT(smem_size <= SM100ArchSpec::smem_capacity);
// Launch
const SMXXFP8MQALogitsRuntime::Args args = {
.seq_len = seq_len,
.seq_len_kv = seq_len_kv,
.max_seqlen_k = max_seqlen_k,
.stride_logits = stride_logits,
.num_heads = num_heads, .head_dim = head_dim,
.is_compressed_logits = is_compressed_logits,
.num_q_stages = num_q_stages,
.num_kv_stages = num_kv_stages,
.block_q = block_q,
.block_kv = block_kv,
.cu_seq_len_k_start = cu_seq_len_k_start.data_ptr<int>(),
.cu_seq_len_k_end = cu_seq_len_k_end.data_ptr<int>(),
.logits = logits.data_ptr(),
.tensor_map_q = tensor_map_q,
.tensor_map_kv = tensor_map_kv,
.tensor_map_kv_scales = tensor_map_kv_scales,
.tensor_map_weights = tensor_map_weights,
.logits_dtype = logits_dtype,
.num_specialized_threads = num_specialized_threads,
.num_math_threads = num_math_threads,
.launch_args = LaunchArgs(device_runtime->get_num_sms(),
num_specialized_threads + num_math_threads,
smem_size)
};
const auto code = SMXXFP8MQALogitsRuntime::generate(args);
const auto runtime = compiler->build("smxx_fp8_mqa_logits", code);
SMXXFP8MQALogitsRuntime::launch(runtime, args);
}
class SM100FP4MQALogitsRuntime final: public LaunchRuntime<SM100FP4MQALogitsRuntime> {
public:
struct Args {
int seq_len;
int seq_len_kv;
int max_seqlen_k;
int stride_logits;
int num_heads, head_dim;
bool is_compressed_logits;
int num_q_stages;
int num_kv_stages;
int block_q;
int block_kv;
int* cu_seq_len_k_start;
int* cu_seq_len_k_end;
void* logits;
CUtensorMap tensor_map_q;
CUtensorMap tensor_map_sf_q;
CUtensorMap tensor_map_kv;
CUtensorMap tensor_map_sf_kv;
CUtensorMap tensor_map_weights;
at::ScalarType logits_dtype;
int num_specialized_threads;
int num_math_threads;
LaunchArgs launch_args;
};
static std::string generate_impl(const Args& args) {
// TODO: optimize performance by tuning args
// Block sizes are fixed in this kernel
DG_HOST_ASSERT(128 % args.num_heads == 0);
const auto arch = device_runtime->get_arch(true);
return fmt::format(R"(
#include <deep_gemm/impls/sm100_fp4_mqa_logits.cuh>
using namespace deep_gemm;
static void __instantiate_kernel() {{
auto ptr = reinterpret_cast<void*>(&sm100_fp4_mqa_logits<
{}, {},
{},
{}, {},
{}, {},
{},
{}, {},
{}
>);
}};
)", args.num_heads, args.head_dim,
args.is_compressed_logits,
args.block_q, args.block_kv,
args.num_q_stages, args.num_kv_stages,
args.launch_args.grid_dim.first,
args.num_specialized_threads, args.num_math_threads,
to_string(args.logits_dtype));
}
static void launch_impl(const KernelHandle& kernel, const LaunchConfigHandle& config, Args args) {
DG_CUDA_UNIFIED_CHECK(launch_kernel(kernel, config,
args.seq_len, args.seq_len_kv,
args.max_seqlen_k, args.stride_logits,
args.cu_seq_len_k_start, args.cu_seq_len_k_end,
args.logits,
args.tensor_map_q, args.tensor_map_sf_q,
args.tensor_map_kv, args.tensor_map_sf_kv,
args.tensor_map_weights
));
}
};
static void sm100_fp4_mqa_logits(const torch::Tensor& q, const torch::Tensor& sf_q,
const torch::Tensor& kv, const torch::Tensor& sf_kv,
const torch::Tensor& weights,
const torch::Tensor& cu_seq_len_k_start,
const torch::Tensor& cu_seq_len_k_end,
const torch::Tensor& logits,
const at::ScalarType& logits_dtype,
const int& seq_len, const int& seq_len_kv,
const int& max_seqlen_k, const int& stride_logits,
const int& num_heads, const int& head_dim,
const int& block_q, const int& block_kv) {
constexpr int num_specialized_threads = 128;
const int num_math_threads = 2 * 128;
constexpr int num_q_stages = 3, num_kv_stages = 6, num_tmem_stages = 3;
// Use compressed logits format when max_seqlen_k is specified
const bool is_compressed_logits = (max_seqlen_k > 0);
// Construct TMAs
// `head_dim` must be 128 for 64B swizzling
DG_HOST_ASSERT(head_dim == 128);
const auto tensor_map_q = make_tma_2d_desc(q, head_dim, seq_len * num_heads,
head_dim, block_q * num_heads,
static_cast<int>(q.stride(1)),
head_dim / 2, 0, false, false);
const auto tensor_map_sf_q = make_tma_2d_desc(sf_q, num_heads, seq_len,
num_heads, block_q,
static_cast<int>(sf_q.stride(0)), 0);
const auto tensor_map_weights = make_tma_2d_desc(weights, num_heads, seq_len,
num_heads, block_q,
static_cast<int>(weights.stride(0)), 0);
const auto tensor_map_kv = make_tma_2d_desc(kv, head_dim, seq_len_kv,
head_dim, block_kv,
static_cast<int>(kv.stride(0)),
head_dim / 2, 0, false, false);
// According to the driver API, the minimal alignment is 256 bytes
// So it is safe for us to do a 16-byte OOB
const auto tensor_map_sf_kv = make_tma_2d_desc(sf_kv,
get_tma_aligned_size(seq_len_kv, static_cast<int>(sf_kv.element_size())), 1,
block_kv, 1, 0, 0);
// Calculate shared memory size
const int smem_q_size_per_stage = block_q * num_heads * head_dim / 2;
const int smem_sf_q_size_per_stage = align(block_q * num_heads, 128) * sizeof(int);
const int smem_kv_size_per_stage = block_kv * head_dim / 2;
const int smem_sf_kv_size_per_stage = align(block_kv, 128) * sizeof(int);
const int smem_weight_size_per_stage = block_q * num_heads * sizeof(float);
const int smem_barriers = (num_q_stages + num_kv_stages + num_tmem_stages) * 2 * 8;
const int smem_tmem_ptr = 4;
const int smem_size = num_q_stages * (smem_q_size_per_stage + smem_sf_q_size_per_stage + smem_weight_size_per_stage) +
num_kv_stages * (smem_kv_size_per_stage + smem_sf_kv_size_per_stage) +
smem_barriers + smem_tmem_ptr;
DG_HOST_ASSERT(smem_size <= SM100ArchSpec::smem_capacity);
// Launch
const SM100FP4MQALogitsRuntime::Args args = {
.seq_len = seq_len,
.seq_len_kv = seq_len_kv,
.max_seqlen_k = max_seqlen_k,
.stride_logits = stride_logits,
.num_heads = num_heads, .head_dim = head_dim,
.is_compressed_logits = is_compressed_logits,
.num_q_stages = num_q_stages,
.num_kv_stages = num_kv_stages,
.block_q = block_q,
.block_kv = block_kv,
.cu_seq_len_k_start = cu_seq_len_k_start.data_ptr<int>(),
.cu_seq_len_k_end = cu_seq_len_k_end.data_ptr<int>(),
.logits = logits.data_ptr(),
.tensor_map_q = tensor_map_q,
.tensor_map_sf_q = tensor_map_sf_q,
.tensor_map_kv = tensor_map_kv,
.tensor_map_sf_kv = tensor_map_sf_kv,
.tensor_map_weights = tensor_map_weights,
.logits_dtype = logits_dtype,
.num_specialized_threads = num_specialized_threads,
.num_math_threads = num_math_threads,
.launch_args = LaunchArgs(device_runtime->get_num_sms(),
num_specialized_threads + num_math_threads,
smem_size)
};
const auto code = SM100FP4MQALogitsRuntime::generate(args);
const auto runtime = compiler->build("sm100_fp4_mqa_logits", code);
SM100FP4MQALogitsRuntime::launch(runtime, args);
}
} // namespace deep_gemm