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Commit 81a882ad authored by jixx's avatar jixx
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add tgi2.4.0

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server/marlin/marlin_kernels/gptq_marlin_dtypes.cuh deleted 100644 → 0
View file @ 9822d7f6
#ifndef _data_types_cuh
#define _data_types_cuh
#include "gptq_marlin.cuh"
#include <cuda_fp16.h>
#include <cuda_bf16.h>
namespace gptq_marlin {
template <typename scalar_t>
class ScalarType {};
template <>
class ScalarType<half> {
public:
using scalar_t = half;
using scalar_t2 = half2;
// Matrix fragments for tensor core instructions; their precise layout is
// documented here:
// https://docs.nvidia.com/cuda/parallel-thread-execution/index.html#matrix-fragments-for-mma-m16n8k16-with-floating-point-type
using FragA = Vec<half2, 4>;
using FragB = Vec<half2, 2>;
using FragC = Vec<float, 4>;
using FragS = Vec<half2, 1>;
static __device__ float inline num2float(const half x) {
return __half2float(x);
}
static __device__ half2 inline num2num2(const half x) {
return __half2half2(x);
}
static __device__ half2 inline nums2num2(const half x1, const half x2) {
return __halves2half2(x1, x2);
}
static __host__ __device__ half inline float2num(const float x) {
return __float2half(x);
}
};
template <>
class ScalarType<nv_bfloat16> {
public:
using scalar_t = nv_bfloat16;
using scalar_t2 = nv_bfloat162;
using FragA = Vec<nv_bfloat162, 4>;
using FragB = Vec<nv_bfloat162, 2>;
using FragC = Vec<float, 4>;
using FragS = Vec<nv_bfloat162, 1>;
#if defined(__CUDA_ARCH__) && __CUDA_ARCH__ >= 800
static __device__ float inline num2float(const nv_bfloat16 x) {
return __bfloat162float(x);
}
static __device__ nv_bfloat162 inline num2num2(const nv_bfloat16 x) {
return __bfloat162bfloat162(x);
}
static __device__ nv_bfloat162 inline nums2num2(const nv_bfloat16 x1,
const nv_bfloat16 x2) {
return __halves2bfloat162(x1, x2);
}
static __host__ __device__ nv_bfloat16 inline float2num(const float x) {
return __float2bfloat16(x);
}
#endif
};
} // namespace gptq_marlin
#endif
server/marlin/marlin_kernels/gptq_marlin_repack.cu deleted 100644 → 0
View file @ 9822d7f6
#include "gptq_marlin.cuh"
namespace gptq_marlin {
static constexpr int repack_stages = 8;
static constexpr int repack_threads = 256;
static constexpr int tile_k_size = tile_size;
static constexpr int tile_n_size = tile_k_size * 4;
#if defined(__CUDA_ARCH__) && __CUDA_ARCH__ < 800
template <int const num_threads, int const num_bits, bool const has_perm>
__global__ void marlin_repack_kernel(
uint32_t const* __restrict__ b_q_weight_ptr,
uint32_t const* __restrict__ perm_ptr, uint32_t* __restrict__ out_ptr,
int size_k, int size_n) {}
} // namespace gptq_marlin
torch::Tensor gptq_marlin_repack(torch::Tensor& b_q_weight, torch::Tensor& perm,
int64_t size_k, int64_t size_n,
int64_t num_bits) {
TORCH_CHECK_NOT_IMPLEMENTED(
false, "marlin_repack_from_gptq(..) requires CUDA_ARCH >= 8.0");
return torch::empty({1, 1});
}
#else
template <int const num_threads, int const num_bits, bool const has_perm>
__global__ void marlin_repack_kernel(
uint32_t const* __restrict__ b_q_weight_ptr,
uint32_t const* __restrict__ perm_ptr, uint32_t* __restrict__ out_ptr,
int size_k, int size_n) {
constexpr int pack_factor = 32 / num_bits;
int k_tiles = size_k / tile_k_size;
int n_tiles = size_n / tile_n_size;
int block_k_tiles = div_ceil(k_tiles, gridDim.x);
int start_k_tile = blockIdx.x * block_k_tiles;
if (start_k_tile >= k_tiles) {
return;
}
int finish_k_tile = min(start_k_tile + block_k_tiles, k_tiles);
// Wait until the next thread tile has been loaded to shared memory.
auto wait_for_stage = [&]() {
// We only have `stages - 2` active fetches since we are double buffering
// and can only issue the next fetch when it is guaranteed that the previous
// shared memory load is fully complete (as it may otherwise be
// overwritten).
cp_async_wait<repack_stages - 2>();
__syncthreads();
};
extern __shared__ int4 sh[];
constexpr int perm_size = tile_k_size / 4;
int4* sh_perm_ptr = sh;
int4* sh_pipe_ptr = sh_perm_ptr;
if constexpr (has_perm) {
sh_pipe_ptr += perm_size;
}
constexpr int tile_ints = tile_k_size / pack_factor;
constexpr int stage_n_threads = tile_n_size / 4;
constexpr int stage_k_threads = has_perm ? tile_k_size : tile_ints;
constexpr int stage_size = stage_k_threads * stage_n_threads;
auto load_perm_to_shared = [&](int k_tile_id) {
int first_k_int4 = (k_tile_id * tile_k_size) / 4;
int4 const* perm_int4_ptr = reinterpret_cast<int4 const*>(perm_ptr);
if (threadIdx.x < perm_size) {
sh_perm_ptr[threadIdx.x] = perm_int4_ptr[first_k_int4 + threadIdx.x];
}
__syncthreads();
};
auto fetch_to_shared = [&](int pipe, int k_tile_id, int n_tile_id) {
if (n_tile_id >= n_tiles) {
cp_async_fence();
return;
}
int first_n = n_tile_id * tile_n_size;
int4* sh_ptr = sh_pipe_ptr + stage_size * pipe;
if constexpr (has_perm) {
if (threadIdx.x < stage_size) {
int k_id = threadIdx.x / stage_n_threads;
int n_id = threadIdx.x % stage_n_threads;
uint32_t const* sh_perm_int_ptr =
reinterpret_cast<uint32_t const*>(sh_perm_ptr);
int src_k = sh_perm_int_ptr[k_id];
int src_k_packed = src_k / pack_factor;
cp_async4(
&sh_ptr[k_id * stage_n_threads + n_id],
reinterpret_cast<int4 const*>(&(
b_q_weight_ptr[src_k_packed * size_n + first_n + (n_id * 4)])));
}
} else {
if (threadIdx.x < stage_size) {
int k_id = threadIdx.x / stage_n_threads;
int n_id = threadIdx.x % stage_n_threads;
int first_k = k_tile_id * tile_k_size;
int first_k_packed = first_k / pack_factor;
cp_async4(&sh_ptr[k_id * stage_n_threads + n_id],
reinterpret_cast<int4 const*>(
&(b_q_weight_ptr[(first_k_packed + k_id) * size_n +
first_n + (n_id * 4)])));
}
}
cp_async_fence();
};
auto repack_tile = [&](int pipe, int k_tile_id, int n_tile_id) {
if (n_tile_id >= n_tiles) {
return;
}
int warp_id = threadIdx.x / 32;
int th_id = threadIdx.x % 32;
if (warp_id >= 4) {
return;
}
int tc_col = th_id / 4;
int tc_row = (th_id % 4) * 2;
constexpr int tc_offsets[4] = {0, 1, 8, 9};
int cur_n = warp_id * 16 + tc_col;
constexpr int sh_stride = 64;
constexpr uint32_t mask = (1 << num_bits) - 1;
int4* sh_stage_ptr = sh_pipe_ptr + stage_size * pipe;
uint32_t* sh_stage_int_ptr = reinterpret_cast<uint32_t*>(sh_stage_ptr);
uint32_t* sh_perm_int_ptr = reinterpret_cast<uint32_t*>(sh_perm_ptr);
uint32_t vals[8];
if constexpr (has_perm) {
for (int i = 0; i < 4; i++) {
int k_idx = tc_row + tc_offsets[i];
uint32_t src_k = sh_perm_int_ptr[k_idx];
uint32_t src_k_pos = src_k % pack_factor;
uint32_t b1_val = sh_stage_int_ptr[k_idx * sh_stride + cur_n];
uint32_t b1_cur_val = (b1_val >> (src_k_pos * num_bits)) & mask;
uint32_t b2_val = sh_stage_int_ptr[k_idx * sh_stride + cur_n + 8];
uint32_t b2_cur_val = (b2_val >> (src_k_pos * num_bits)) & mask;
vals[i] = b1_cur_val;
vals[4 + i] = b2_cur_val;
}
} else {
uint32_t b1_vals[tile_ints];
uint32_t b2_vals[tile_ints];
#pragma unroll
for (int i = 0; i < tile_ints; i++) {
b1_vals[i] = sh_stage_int_ptr[cur_n + sh_stride * i];
b2_vals[i] = sh_stage_int_ptr[cur_n + 8 + sh_stride * i];
}
#pragma unroll
for (int i = 0; i < 4; i++) {
int cur_elem = tc_row + tc_offsets[i];
int cur_int = cur_elem / pack_factor;
int cur_pos = cur_elem % pack_factor;
vals[i] = (b1_vals[cur_int] >> (cur_pos * num_bits)) & mask;
vals[4 + i] = (b2_vals[cur_int] >> (cur_pos * num_bits)) & mask;
}
}
constexpr int tile_size = tile_k_size * tile_n_size / pack_factor;
int out_offset = (k_tile_id * n_tiles + n_tile_id) * tile_size;
// Result of:
// https://github.com/NVIDIA/FasterTransformer/blob/main/src/fastertransformer/cutlass_extensions/include/cutlass_extensions/interleaved_numeric_conversion.h
if constexpr (num_bits == 4) {
constexpr int pack_idx[8] = {0, 2, 4, 6, 1, 3, 5, 7};
uint32_t res = 0;
#pragma unroll
for (int i = 0; i < 8; i++) {
res |= vals[pack_idx[i]] << (i * 4);
}
out_ptr[out_offset + th_id * 4 + warp_id] = res;
} else {
constexpr int pack_idx[4] = {0, 2, 1, 3};
uint32_t res1 = 0;
uint32_t res2 = 0;
#pragma unroll
for (int i = 0; i < 4; i++) {
res1 |= vals[pack_idx[i]] << (i * 8);
res2 |= vals[4 + pack_idx[i]] << (i * 8);
}
out_ptr[out_offset + th_id * 8 + (warp_id * 2) + 0] = res1;
out_ptr[out_offset + th_id * 8 + (warp_id * 2) + 1] = res2;
}
};
auto start_pipes = [&](int k_tile_id, int n_tile_id) {
#pragma unroll
for (int pipe = 0; pipe < repack_stages - 1; pipe++) {
fetch_to_shared(pipe, k_tile_id, n_tile_id + pipe);
}
wait_for_stage();
};
#pragma unroll
for (int k_tile_id = start_k_tile; k_tile_id < finish_k_tile; k_tile_id++) {
int n_tile_id = 0;
if constexpr (has_perm) {
load_perm_to_shared(k_tile_id);
}
start_pipes(k_tile_id, n_tile_id);
while (n_tile_id < n_tiles) {
#pragma unroll
for (int pipe = 0; pipe < repack_stages; pipe++) {
fetch_to_shared((pipe + repack_stages - 1) % repack_stages, k_tile_id,
n_tile_id + pipe + repack_stages - 1);
repack_tile(pipe, k_tile_id, n_tile_id + pipe);
wait_for_stage();
}
n_tile_id += repack_stages;
}
}
}
} // namespace gptq_marlin
#define CALL_IF(NUM_BITS, HAS_PERM) \
else if (num_bits == NUM_BITS && has_perm == HAS_PERM) { \
cudaFuncSetAttribute( \
gptq_marlin::marlin_repack_kernel<gptq_marlin::repack_threads, \
NUM_BITS, HAS_PERM>, \
cudaFuncAttributeMaxDynamicSharedMemorySize, max_shared_mem); \
gptq_marlin::marlin_repack_kernel<gptq_marlin::repack_threads, NUM_BITS, \
HAS_PERM> \
<<<blocks, gptq_marlin::repack_threads, max_shared_mem, stream>>>( \
b_q_weight_ptr, perm_ptr, out_ptr, size_k, size_n); \
}
torch::Tensor gptq_marlin_repack(torch::Tensor& b_q_weight, torch::Tensor& perm,
int64_t size_k, int64_t size_n,
int64_t num_bits) {
// Verify compatibility with marlin tile of 16x64
TORCH_CHECK(size_k % gptq_marlin::tile_k_size == 0, "size_k = ", size_k,
" is not divisible by tile_k_size = ", gptq_marlin::tile_k_size);
TORCH_CHECK(size_n % gptq_marlin::tile_n_size == 0, "size_n = ", size_n,
" is not divisible by tile_n_size = ", gptq_marlin::tile_n_size);
TORCH_CHECK(num_bits == 4 || num_bits == 8,
"num_bits must be 4 or 8. Got = ", num_bits);
int const pack_factor = 32 / num_bits;
// Verify B
TORCH_CHECK((size_k / pack_factor) == b_q_weight.size(0),
"Shape mismatch: b_q_weight.size(0) = ", b_q_weight.size(0),
", size_k = ", size_k, ", pack_factor = ", pack_factor);
TORCH_CHECK(b_q_weight.size(1) == size_n,
"b_q_weight.size(1) = ", b_q_weight.size(1),
" is not size_n = ", size_n);
// Verify device and strides
TORCH_CHECK(b_q_weight.device().is_cuda(), "b_q_weight is not on GPU");
TORCH_CHECK(b_q_weight.is_contiguous(), "b_q_weight is not contiguous");
TORCH_CHECK(b_q_weight.dtype() == at::kInt, "b_q_weight type is not kInt");
TORCH_CHECK(perm.device().is_cuda(), "perm is not on GPU");
TORCH_CHECK(perm.is_contiguous(), "perm is not contiguous");
TORCH_CHECK(perm.dtype() == at::kInt, "perm type is not at::kInt");
// Alloc buffers
const at::cuda::OptionalCUDAGuard device_guard(device_of(b_q_weight));
auto options = torch::TensorOptions()
.dtype(b_q_weight.dtype())
.device(b_q_weight.device());
torch::Tensor out =
torch::empty({size_k / gptq_marlin::tile_size,
size_n * gptq_marlin::tile_size / pack_factor},
options);
// Detect if there is act_order
bool has_perm = perm.size(0) != 0;
// Get ptrs
uint32_t const* b_q_weight_ptr =
reinterpret_cast<uint32_t const*>(b_q_weight.data_ptr());
uint32_t const* perm_ptr = reinterpret_cast<uint32_t const*>(perm.data_ptr());
uint32_t* out_ptr = reinterpret_cast<uint32_t*>(out.data_ptr());
// Get dev info
int dev = b_q_weight.get_device();
cudaStream_t stream = at::cuda::getCurrentCUDAStream(dev);
int blocks;
cudaDeviceGetAttribute(&blocks, cudaDevAttrMultiProcessorCount, dev);
int max_shared_mem = 0;
cudaDeviceGetAttribute(&max_shared_mem,
cudaDevAttrMaxSharedMemoryPerBlockOptin, dev);
TORCH_CHECK(max_shared_mem > 0);
if (false) {
}
CALL_IF(4, false)
CALL_IF(4, true)
CALL_IF(8, false)
CALL_IF(8, true)
else {
TORCH_CHECK(false, "Unsupported repack config: num_bits = ", num_bits,
", has_perm = ", has_perm);
}
return out;
}
#endif
server/marlin/marlin_kernels/marlin_cuda_kernel.cu deleted 100644 → 0
View file @ 9822d7f6
/*
* Modified by Neural Magic
* Copyright (C) Marlin.2024 Elias Frantar
*
* 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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 <torch/all.h>
#include <ATen/cuda/CUDAContext.h>
#include <c10/cuda/CUDAGuard.h>
#include <cuda.h>
#include <cuda_fp16.h>
#include <cuda_runtime.h>
#include <iostream>
template <typename T>
inline std::string str(T x) {
return std::to_string(x);
}
namespace marlin {
constexpr int ceildiv(int a, int b) { return (a + b - 1) / b; }
#if defined(__CUDA_ARCH__) && __CUDA_ARCH__ >= 800
// Instances of `Vec` are used to organize groups of >>registers<<, as needed
// for instance as inputs to tensor core operations. Consequently, all
// corresponding index accesses must be compile-time constants, which is why we
// extensively use `#pragma unroll` throughout the kernel code to guarantee
// this.
template <typename T, int n>
struct Vec {
T elems[n];
__device__ T& operator[](int i) { return elems[i]; }
};
using I4 = Vec<int, 4>;
// Matrix fragments for tensor core instructions; their precise layout is
// documented here:
// https://docs.nvidia.com/cuda/parallel-thread-execution/index.html#matrix-fragments-for-mma-m16n8k16-with-floating-point-type
using FragA = Vec<half2, 4>;
using FragB = Vec<half2, 2>;
using FragC = Vec<float, 4>;
using FragS = Vec<half2, 1>; // quantization scales
// Predicated asynchronous global->shared copy; used for inputs A where we apply
// predication to handle batchsizes that are not multiples of 16.
__device__ inline void cp_async4_pred(void* smem_ptr, const void* glob_ptr,
bool pred = true) {
const int BYTES = 16;
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile(
"{\n"
" .reg .pred p;\n"
" setp.ne.b32 p, %0, 0;\n"
" @p cp.async.cg.shared.global [%1], [%2], %3;\n"
"}\n" ::"r"((int)pred),
"r"(smem), "l"(glob_ptr), "n"(BYTES));
}
// Asynchronous global->shared copy
__device__ inline void cp_async4(void* smem_ptr, const void* glob_ptr) {
const int BYTES = 16;
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile(
"{\n"
" cp.async.cg.shared.global [%0], [%1], %2;\n"
"}\n" ::"r"(smem),
"l"(glob_ptr), "n"(BYTES));
}
// Async copy fence.
__device__ inline void cp_async_fence() {
asm volatile("cp.async.commit_group;\n" ::);
}
// Wait until at most `n` async copy stages are still pending.
template <int n>
__device__ inline void cp_async_wait() {
asm volatile("cp.async.wait_group %0;\n" ::"n"(n));
}
// m16n8k16 tensor core mma instruction with fp16 inputs and fp32
// output/accumulation.
__device__ inline void mma(const FragA& a_frag, const FragB& frag_b,
FragC& frag_c) {
const uint32_t* a = reinterpret_cast<const uint32_t*>(&a_frag);
const uint32_t* b = reinterpret_cast<const uint32_t*>(&frag_b);
float* c = reinterpret_cast<float*>(&frag_c);
asm volatile(
"mma.sync.aligned.m16n8k16.row.col.f32.f16.f16.f32 "
"{%0,%1,%2,%3}, {%4,%5,%6,%7}, {%8,%9}, {%10,%11,%12,%13};\n"
: "=f"(c[0]), "=f"(c[1]), "=f"(c[2]), "=f"(c[3])
: "r"(a[0]), "r"(a[1]), "r"(a[2]), "r"(a[3]), "r"(b[0]), "r"(b[1]),
"f"(c[0]), "f"(c[1]), "f"(c[2]), "f"(c[3]));
}
// Instruction for loading a full 16x16 matrix fragment of operand A from shared
// memory, directly in tensor core layout.
__device__ inline void ldsm4(FragA& frag_a, const void* smem_ptr) {
uint32_t* a = reinterpret_cast<uint32_t*>(&frag_a);
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile("ldmatrix.sync.aligned.m8n8.x4.shared.b16 {%0,%1,%2,%3}, [%4];\n"
: "=r"(a[0]), "=r"(a[1]), "=r"(a[2]), "=r"(a[3])
: "r"(smem));
}
// Lookup-table based 3-input logical operation; explicitly used for
// dequantization as the compiler does not seem to automatically recognize it in
// all cases.
template <int lut>
__device__ inline int lop3(int a, int b, int c) {
int res;
asm volatile("lop3.b32 %0, %1, %2, %3, %4;\n"
: "=r"(res)
: "r"(a), "r"(b), "r"(c), "n"(lut));
return res;
}
// Efficiently dequantize an int32 value into a full B-fragment of 4 fp16
// values. We mostly follow the strategy in the link below, with some small
// changes:
// https://github.com/NVIDIA/FasterTransformer/blob/main/src/fastertransformer/cutlass_extensions/include/cutlass_extensions/interleaved_numeric_conversion.h
__device__ inline FragB dequant(int q) {
const int LO = 0x000f000f;
const int HI = 0x00f000f0;
const int EX = 0x64006400;
// Guarantee that the `(a & b) | c` operations are LOP3s.
int lo = lop3<(0xf0 & 0xcc) | 0xaa>(q, LO, EX);
int hi = lop3<(0xf0 & 0xcc) | 0xaa>(q, HI, EX);
// We want signed int4 outputs, hence we fuse the `-8` symmetric zero point
// directly into `SUB` and `ADD`.
const int SUB = 0x64086408;
const int MUL = 0x2c002c00;
const int ADD = 0xd480d480;
FragB frag_b;
frag_b[0] = __hsub2(*reinterpret_cast<half2*>(&lo),
*reinterpret_cast<const half2*>(&SUB));
frag_b[1] = __hfma2(*reinterpret_cast<half2*>(&hi),
*reinterpret_cast<const half2*>(&MUL),
*reinterpret_cast<const half2*>(&ADD));
return frag_b;
}
// Multiply dequantized values by the corresponding quantization scale; used
// only for grouped quantization.
__device__ inline void scale(FragB& frag_b, FragS& frag_s, int i) {
half2 s = __half2half2(reinterpret_cast<__half*>(&frag_s)[i]);
frag_b[0] = __hmul2(frag_b[0], s);
frag_b[1] = __hmul2(frag_b[1], s);
}
// Wait until barrier reaches `count`, then lock for current threadblock.
__device__ inline void barrier_acquire(int* lock, int count) {
if (threadIdx.x == 0) {
int state = -1;
do
// Guarantee that subsequent writes by this threadblock will be visible
// globally.
asm volatile("ld.global.acquire.gpu.b32 %0, [%1];\n"
: "=r"(state)
: "l"(lock));
while (state != count);
}
__syncthreads();
}
// Release barrier and increment visitation count.
__device__ inline void barrier_release(int* lock, bool reset = false) {
__syncthreads();
if (threadIdx.x == 0) {
if (reset) {
lock[0] = 0;
return;
}
int val = 1;
// Make sure that all writes since acquiring this barrier are visible
// globally, while releasing the barrier.
asm volatile("fence.acq_rel.gpu;\n");
asm volatile("red.relaxed.gpu.global.add.s32 [%0], %1;\n"
:
: "l"(lock), "r"(val));
}
}
template <const int threads, // number of threads in a threadblock
const int thread_m_blocks, // number of 16x16 blocks in the m
// dimension (batchsize) of the
// threadblock
const int thread_n_blocks, // same for n dimension (output)
const int thread_k_blocks, // same for k dimension (reduction)
const int stages, // number of stages for the async global->shared
// fetch pipeline
const int group_blocks = -1 // number of consecutive 16x16 blocks
// with a separate quantization scale
>
__global__ void Marlin(
const int4* __restrict__ A, // fp16 input matrix of shape mxk
const int4* __restrict__ B, // 4bit quantized weight matrix of shape kxn
int4* __restrict__ C, // fp16 output buffer of shape mxn
const int4* __restrict__ s, // fp16 quantization scales of shape
// (k/groupsize)xn
int prob_m, // batch dimension m
int prob_n, // output dimension n
int prob_k, // reduction dimension k
int* locks // extra global storage for barrier synchronization
) {
// Each threadblock processes one "stripe" of the B matrix with (roughly) the
// same size, which might involve multiple column "slices" (of width 16 *
// `thread_n_blocks`). Stripes are defined as shown in the 3x3 matrix 5 SM
// example:
// 0 1 3
// 0 2 3
// 1 2 4
// While this kind of partitioning makes things somewhat more complicated, it
// ensures good utilization of all SMs for many kinds of shape and GPU
// configurations, while requiring as few slow global cross-threadblock
// reductions as possible.
// For larger GEMMs we run multiple batchsize 64 versions in parallel for a
// better partitioning with less reductions
int parallel = 1;
if (prob_m > 16 * thread_m_blocks) {
parallel = prob_m / (16 * thread_m_blocks);
prob_m = 16 * thread_m_blocks;
}
int k_tiles = prob_k / 16 / thread_k_blocks;
int n_tiles = prob_n / 16 / thread_n_blocks;
int iters = ceildiv(k_tiles * n_tiles * parallel, gridDim.x);
// Ensure that the number of tiles in each stripe is a multiple of the
// groupsize; this avoids an annoying special case where a stripe starts in
// the middle of group.
if (group_blocks != -1)
iters = (group_blocks / thread_k_blocks) *
ceildiv(iters, (group_blocks / thread_k_blocks));
int slice_row = (iters * blockIdx.x) % k_tiles;
int slice_col_par = (iters * blockIdx.x) / k_tiles;
int slice_col = slice_col_par;
int slice_iters; // number of threadblock tiles in the current slice
int slice_count =
0; // total number of active threadblocks in the current slice
int slice_idx; // index of threadblock in current slice; numbered bottom to
// top
// We can easily implement parallel problem execution by just remapping
// indices and advancing global pointers
if (slice_col_par >= n_tiles) {
A += (slice_col_par / n_tiles) * 16 * thread_m_blocks * prob_k / 8;
C += (slice_col_par / n_tiles) * 16 * thread_m_blocks * prob_n / 8;
locks += (slice_col_par / n_tiles) * n_tiles;
slice_col = slice_col_par % n_tiles;
}
// Compute all information about the current slice which is required for
// synchronization.
auto init_slice = [&]() {
slice_iters =
iters * (blockIdx.x + 1) - (k_tiles * slice_col_par + slice_row);
if (slice_iters < 0 || slice_col_par >= n_tiles * parallel) slice_iters = 0;
if (slice_iters == 0) return;
if (slice_row + slice_iters > k_tiles) slice_iters = k_tiles - slice_row;
slice_count = 1;
slice_idx = 0;
int col_first = iters * ceildiv(k_tiles * slice_col_par, iters);
if (col_first <= k_tiles * (slice_col_par + 1)) {
int col_off = col_first - k_tiles * slice_col_par;
slice_count = ceildiv(k_tiles - col_off, iters);
if (col_off > 0) slice_count++;
int delta_first = iters * blockIdx.x - col_first;
if (delta_first < 0 || (col_off == 0 && delta_first == 0))
slice_idx = slice_count - 1;
else {
slice_idx = slice_count - 1 - delta_first / iters;
if (col_off > 0) slice_idx--;
}
}
if (slice_col == n_tiles) {
A += 16 * thread_m_blocks * prob_k / 8;
C += 16 * thread_m_blocks * prob_n / 8;
locks += n_tiles;
slice_col = 0;
}
};
init_slice();
int a_gl_stride = prob_k / 8; // stride of the A matrix in global memory
// We typically use `constexpr` to indicate that this value is a compile-time
// constant
constexpr int a_sh_stride =
16 * thread_k_blocks / 8; // stride of an A matrix tile in shared memory
constexpr int a_gl_rd_delta_o =
16 * thread_k_blocks /
8; // delta between subsequent A tiles in global memory
int a_gl_rd_delta_i =
a_gl_stride *
(threads / a_gl_rd_delta_o); // between subsequent accesses within a tile
constexpr int a_sh_wr_delta =
a_sh_stride *
(threads / a_gl_rd_delta_o); // between shared memory writes
constexpr int a_sh_rd_delta_o =
2 * ((threads / 32) /
(thread_n_blocks / 4)); // between shared memory tile reads
constexpr int a_sh_rd_delta_i =
a_sh_stride * 16; // within a shared memory tile
constexpr int a_sh_stage =
a_sh_stride * (16 * thread_m_blocks); // overall size of a tile
constexpr int a_sh_wr_iters =
ceildiv(a_sh_stage,
a_sh_wr_delta); // number of shared write iterations for a tile
int b_gl_stride = 16 * prob_n / 32;
constexpr int b_sh_stride = 32 * thread_n_blocks / 4;
int b_gl_rd_delta_o = b_gl_stride * thread_k_blocks;
int b_gl_rd_delta_i = b_gl_stride * (threads / b_sh_stride);
constexpr int b_sh_wr_delta = threads;
constexpr int b_sh_rd_delta = threads;
constexpr int b_sh_stage = b_sh_stride * thread_k_blocks;
constexpr int b_sh_wr_iters = b_sh_stage / b_sh_wr_delta;
int s_gl_stride = prob_n / 8;
constexpr int s_sh_stride = 16 * thread_n_blocks / 8;
constexpr int s_sh_stage = s_sh_stride;
int s_gl_rd_delta = s_gl_stride;
// Global A read index of current thread.
int a_gl_rd = a_gl_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
a_gl_rd += a_gl_rd_delta_o * slice_row;
// Shared write index of current thread.
int a_sh_wr = a_sh_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
// Shared read index.
int a_sh_rd =
a_sh_stride * ((threadIdx.x % 32) % 16) + (threadIdx.x % 32) / 16;
a_sh_rd += 2 * ((threadIdx.x / 32) / (thread_n_blocks / 4));
int b_gl_rd =
b_gl_stride * (threadIdx.x / b_sh_stride) + (threadIdx.x % b_sh_stride);
b_gl_rd += b_sh_stride * slice_col;
b_gl_rd += b_gl_rd_delta_o * slice_row;
int b_sh_wr = threadIdx.x;
int b_sh_rd = threadIdx.x;
int s_gl_rd = s_gl_stride * ((thread_k_blocks * slice_row) / group_blocks) +
s_sh_stride * slice_col + threadIdx.x;
int s_sh_wr = threadIdx.x;
int s_sh_rd;
// We use a different scale layout for grouped and column-wise quantization as
// we scale a `half2` tile in column-major layout in the former and in
// row-major in the latter case.
if (group_blocks != -1)
s_sh_rd = 8 * ((threadIdx.x / 32) % (thread_n_blocks / 4)) +
(threadIdx.x % 32) / 4;
else
s_sh_rd = 8 * ((threadIdx.x / 32) % (thread_n_blocks / 4)) +
(threadIdx.x % 32) % 4;
// Precompute which thread should not read memory in which iterations; this is
// needed if there are more threads than required for a certain tilesize or
// when the batchsize is not a multiple of 16.
bool a_sh_wr_pred[a_sh_wr_iters];
#pragma unroll
for (int i = 0; i < a_sh_wr_iters; i++)
a_sh_wr_pred[i] = a_sh_wr_delta * i + a_sh_wr < a_sh_stride * prob_m;
bool s_sh_wr_pred = threadIdx.x < s_sh_stride;
// To ensure that writing and reading A tiles to/from shared memory, the
// latter in fragment format, is fully bank conflict free, we need to use a
// rather fancy XOR-based layout. The key here is that neither reads nor
// writes of the 16-byte `int4` blocks of 8 consecutive threads involve the
// same shared memory banks. Further, it seems (based on NSight-Compute) that
// each warp must also write a consecutive memory segment?
auto transform_a = [&](int i) {
int row = i / a_gl_rd_delta_o;
return a_gl_rd_delta_o * row + (i % a_gl_rd_delta_o) ^ row;
};
// Since the computation of this remapping is non-trivial and, due to our main
// loop unrolls, all shared memory accesses are static, we simply precompute
// both transformed reads and writes.
int a_sh_wr_trans[a_sh_wr_iters];
#pragma unroll
for (int i = 0; i < a_sh_wr_iters; i++)
a_sh_wr_trans[i] = transform_a(a_sh_wr_delta * i + a_sh_wr);
int a_sh_rd_trans[b_sh_wr_iters][thread_m_blocks];
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) {
#pragma unroll
for (int j = 0; j < thread_m_blocks; j++)
a_sh_rd_trans[i][j] =
transform_a(a_sh_rd_delta_o * i + a_sh_rd_delta_i * j + a_sh_rd);
}
// Since B-accesses have non-constant stride they have to be computed at
// runtime; we break dependencies between subsequent accesses with a tile by
// maintining multiple pointers (we have enough registers), a tiny
// optimization.
const int4* B_ptr[b_sh_wr_iters];
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++)
B_ptr[i] = B + b_gl_rd_delta_i * i + b_gl_rd;
extern __shared__ int4 sh[];
// Shared memory storage for global fetch pipelines.
int4* sh_a = sh;
int4* sh_b = sh_a + (stages * a_sh_stage);
int4* sh_s = sh_b + (stages * b_sh_stage);
// Register storage for double buffer of shared memory reads.
FragA frag_a[2][thread_m_blocks];
I4 frag_b_quant[2];
FragC frag_c[thread_m_blocks][4][2];
FragS frag_s[2][4];
// Zero accumulators.
auto zero_accums = [&]() {
#pragma unroll
for (int i = 0; i < thread_m_blocks * 4 * 2 * 4; i++)
reinterpret_cast<float*>(frag_c)[i] = 0;
};
// Asynchronously fetch the next A, B and s tile from global to the next
// shared memory pipeline location.
auto fetch_to_shared = [&](int pipe, int a_off, bool pred = true) {
if (pred) {
int4* sh_a_stage = sh_a + a_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < a_sh_wr_iters; i++) {
cp_async4_pred(
&sh_a_stage[a_sh_wr_trans[i]],
&A[a_gl_rd_delta_i * i + a_gl_rd + a_gl_rd_delta_o * a_off],
a_sh_wr_pred[i]);
}
int4* sh_b_stage = sh_b + b_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) {
cp_async4(&sh_b_stage[b_sh_wr_delta * i + b_sh_wr], B_ptr[i]);
B_ptr[i] += b_gl_rd_delta_o;
}
// Only fetch scales if this tile starts a new group
if (group_blocks != -1 && pipe % (group_blocks / thread_k_blocks) == 0) {
int4* sh_s_stage = sh_s + s_sh_stage * pipe;
if (s_sh_wr_pred) cp_async4(&sh_s_stage[s_sh_wr], &s[s_gl_rd]);
s_gl_rd += s_gl_rd_delta;
}
}
// Insert a fence even when we are winding down the pipeline to ensure that
// waiting is also correct at this point.
cp_async_fence();
};
// Wait until the next thread tile has been loaded to shared memory.
auto wait_for_stage = [&]() {
// We only have `stages - 2` active fetches since we are double buffering
// and can only issue the next fetch when it is guaranteed that the previous
// shared memory load is fully complete (as it may otherwise be
// overwritten).
cp_async_wait<stages - 2>();
__syncthreads();
};
// Load the next sub-tile from the current location in the shared memory pipe
// into the current register buffer.
auto fetch_to_registers = [&](int k, int pipe) {
// It may seem inefficient that we reload the groups for every sub-tile;
// however, this does not seem to be a significant bottleneck, while some
// theoretically better attempts have lead to bad instruction ordering by
// the compiler and correspondingly a noticeable drop in performance.
if (group_blocks != -1) {
int4* sh_s_stage =
sh_s + s_sh_stage * ((group_blocks / thread_k_blocks) *
(pipe / (group_blocks / thread_k_blocks)));
reinterpret_cast<int4*>(&frag_s[k % 2])[0] = sh_s_stage[s_sh_rd];
}
int4* sh_a_stage = sh_a + a_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++)
ldsm4(frag_a[k % 2][i], &sh_a_stage[a_sh_rd_trans[k % b_sh_wr_iters][i]]);
int4* sh_b_stage = sh_b + b_sh_stage * pipe;
frag_b_quant[k % 2] = *reinterpret_cast<I4*>(
&sh_b_stage[b_sh_rd_delta * (k % b_sh_wr_iters) + b_sh_rd]);
};
// Execute the actual tensor core matmul of a sub-tile.
auto matmul = [&](int k) {
// We have the m dimension as the inner loop in order to encourage overlapping
// dequantization and matmul operations.
#pragma unroll
for (int j = 0; j < 4; j++) {
int b_quant = frag_b_quant[k % 2][j];
int b_quant_shift = b_quant >> 8;
FragB frag_b0 = dequant(b_quant);
// If there are no groups, we can just scale the final output once and can
// avoid doing so for each weight.
if (group_blocks != -1) scale(frag_b0, frag_s[k % 2][j], 0);
FragB frag_b1 = dequant(b_quant_shift);
if (group_blocks != -1) scale(frag_b1, frag_s[k % 2][j], 1);
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
mma(frag_a[k % 2][i], frag_b0, frag_c[i][j][0]);
mma(frag_a[k % 2][i], frag_b1, frag_c[i][j][1]);
}
}
};
// Since we slice across the k dimension of a tile in order to increase the
// number of warps while keeping the n dimension of a tile reasonable, we have
// multiple warps that accumulate their partial sums of the same output
// location; which we have to reduce over in the end. We do in shared memory.
auto thread_block_reduce = [&]() {
constexpr int red_off = threads / b_sh_stride / 2;
if (red_off >= 1) {
int red_idx = threadIdx.x / b_sh_stride;
constexpr int red_sh_stride = b_sh_stride * 4 * 2;
constexpr int red_sh_delta = b_sh_stride;
int red_sh_rd = red_sh_stride * (threadIdx.x / b_sh_stride) +
(threadIdx.x % b_sh_stride);
// Parallel logarithmic shared memory reduction. We make sure to avoid any
// unnecessary read or write iterations, e.g., for two warps we write only
// once by warp 1 and read only once by warp 0.
#pragma unroll
for (int m_block = 0; m_block < thread_m_blocks; m_block++) {
#pragma unroll
for (int i = red_off; i > 0; i /= 2) {
if (i <= red_idx && red_idx < 2 * i) {
#pragma unroll
for (int j = 0; j < 4 * 2; j++) {
int red_sh_wr =
red_sh_delta * j + (red_sh_rd - red_sh_stride * i);
if (i < red_off) {
float* c_rd =
reinterpret_cast<float*>(&sh[red_sh_delta * j + red_sh_rd]);
float* c_wr = reinterpret_cast<float*>(&sh[red_sh_wr]);
#pragma unroll
for (int k = 0; k < 4; k++)
reinterpret_cast<FragC*>(frag_c)[4 * 2 * m_block + j][k] +=
c_rd[k] + c_wr[k];
}
sh[red_sh_wr] =
reinterpret_cast<int4*>(&frag_c)[4 * 2 * m_block + j];
}
}
__syncthreads();
}
if (red_idx == 0) {
#pragma unroll
for (int i = 0; i < 4 * 2; i++) {
float* c_rd =
reinterpret_cast<float*>(&sh[red_sh_delta * i + red_sh_rd]);
#pragma unroll
for (int j = 0; j < 4; j++)
reinterpret_cast<FragC*>(frag_c)[4 * 2 * m_block + i][j] +=
c_rd[j];
}
}
__syncthreads();
}
}
};
// Since multiple threadblocks may process parts of the same column slice, we
// finally have to globally reduce over the results. As the striped
// partitioning minimizes the number of such reductions and our outputs are
// usually rather small, we perform this reduction serially in L2 cache.
auto global_reduce = [&](bool first = false, bool last = false) {
// We are very careful here to reduce directly in the output buffer to
// maximize L2 cache utilization in this step. To do this, we write out
// results in FP16 (but still reduce with FP32 compute).
constexpr int active_threads = 32 * thread_n_blocks / 4;
if (threadIdx.x < active_threads) {
int c_gl_stride = prob_n / 8;
int c_gl_wr_delta_o = 8 * c_gl_stride;
int c_gl_wr_delta_i = 4 * (active_threads / 32);
int c_gl_wr = c_gl_stride * ((threadIdx.x % 32) / 4) +
4 * (threadIdx.x / 32) + threadIdx.x % 4;
c_gl_wr += (2 * thread_n_blocks) * slice_col;
constexpr int c_sh_wr_delta = active_threads;
int c_sh_wr = threadIdx.x;
int row = (threadIdx.x % 32) / 4;
if (!first) {
// Interestingly, doing direct global accesses here really seems to mess up
// the compiler and lead to slowdowns, hence we also use async-copies even
// though these fetches are not actually asynchronous.
#pragma unroll
for (int i = 0; i < thread_m_blocks * 4; i++) {
cp_async4_pred(
&sh[c_sh_wr + c_sh_wr_delta * i],
&C[c_gl_wr + c_gl_wr_delta_o * (i / 2) +
c_gl_wr_delta_i * (i % 2)],
i < (thread_m_blocks - 1) * 4 || 8 * (i / 2) + row < prob_m);
}
cp_async_fence();
cp_async_wait<0>();
}
#pragma unroll
for (int i = 0; i < thread_m_blocks * 4; i++) {
if (i < (thread_m_blocks - 1) * 4 || 8 * (i / 2) + row < prob_m) {
if (!first) {
int4 c_red = sh[c_sh_wr + i * c_sh_wr_delta];
#pragma unroll
for (int j = 0; j < 2 * 4; j++) {
reinterpret_cast<float*>(
&frag_c)[4 * 2 * 4 * (i / 4) + 4 * j + (i % 4)] +=
__half2float(reinterpret_cast<__half*>(&c_red)[j]);
}
}
if (!last) {
int4 c;
#pragma unroll
for (int j = 0; j < 2 * 4; j++) {
reinterpret_cast<__half*>(&c)[j] =
__float2half(reinterpret_cast<float*>(
&frag_c)[4 * 2 * 4 * (i / 4) + 4 * j + (i % 4)]);
}
C[c_gl_wr + c_gl_wr_delta_o * (i / 2) + c_gl_wr_delta_i * (i % 2)] =
c;
}
}
}
}
};
// Write out the reduce final result in the correct layout. We only actually
// reshuffle matrix fragments in this step, the reduction above is performed
// in fragment layout.
auto write_result = [&]() {
int c_gl_stride = prob_n / 8;
constexpr int c_sh_stride = 2 * thread_n_blocks + 1;
int c_gl_wr_delta = c_gl_stride * (threads / (2 * thread_n_blocks));
constexpr int c_sh_rd_delta =
c_sh_stride * (threads / (2 * thread_n_blocks));
int c_gl_wr = c_gl_stride * (threadIdx.x / (2 * thread_n_blocks)) +
(threadIdx.x % (2 * thread_n_blocks));
c_gl_wr += (2 * thread_n_blocks) * slice_col;
int c_sh_wr =
(4 * c_sh_stride) * ((threadIdx.x % 32) / 4) + (threadIdx.x % 32) % 4;
c_sh_wr += 32 * (threadIdx.x / 32);
int c_sh_rd = c_sh_stride * (threadIdx.x / (2 * thread_n_blocks)) +
(threadIdx.x % (2 * thread_n_blocks));
int c_gl_wr_end = c_gl_stride * prob_m;
// We first reorder in shared memory to guarantee the most efficient final
// global write patterns
auto write = [&](int idx, float c0, float c1, FragS& s) {
half2 res = __halves2half2(__float2half(c0), __float2half(c1));
if (group_blocks ==
-1) // for per-column quantization we finally apply the scale here
res = __hmul2(res, s[0]);
((half2*)sh)[idx] = res;
};
if (threadIdx.x / 32 < thread_n_blocks / 4) {
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
#pragma unroll
for (int j = 0; j < 4; j++) {
int wr = c_sh_wr + 8 * j;
write(wr + (4 * c_sh_stride) * 0 + 0, frag_c[i][j][0][0],
frag_c[i][j][0][1], frag_s[j / 2][2 * (j % 2) + 0]);
write(wr + (4 * c_sh_stride) * 8 + 0, frag_c[i][j][0][2],
frag_c[i][j][0][3], frag_s[j / 2][2 * (j % 2) + 0]);
write(wr + (4 * c_sh_stride) * 0 + 4, frag_c[i][j][1][0],
frag_c[i][j][1][1], frag_s[j / 2][2 * (j % 2) + 1]);
write(wr + (4 * c_sh_stride) * 8 + 4, frag_c[i][j][1][2],
frag_c[i][j][1][3], frag_s[j / 2][2 * (j % 2) + 1]);
}
c_sh_wr += 16 * (4 * c_sh_stride);
}
}
__syncthreads();
#pragma unroll
for (int i = 0;
i < ceildiv(16 * thread_m_blocks, threads / (2 * thread_n_blocks));
i++) {
if (c_gl_wr < c_gl_wr_end) {
C[c_gl_wr] = sh[c_sh_rd];
c_gl_wr += c_gl_wr_delta;
c_sh_rd += c_sh_rd_delta;
}
}
};
// Start global fetch and register load pipelines.
auto start_pipes = [&]() {
#pragma unroll
for (int i = 0; i < stages - 1; i++) fetch_to_shared(i, i, i < slice_iters);
zero_accums();
wait_for_stage();
fetch_to_registers(0, 0);
a_gl_rd += a_gl_rd_delta_o * (stages - 1);
};
start_pipes();
// Main loop.
while (slice_iters) {
// We unroll over both the global fetch and the register load pipeline to
// ensure all shared memory accesses are static. Note that both pipelines have
// even length meaning that the next iteration will always start at index 0.
#pragma unroll
for (int pipe = 0; pipe < stages;) {
#pragma unroll
for (int k = 0; k < b_sh_wr_iters; k++) {
fetch_to_registers(k + 1, pipe % stages);
if (k == b_sh_wr_iters - 2) {
fetch_to_shared((pipe + stages - 1) % stages, pipe,
slice_iters >= stages);
pipe++;
wait_for_stage();
}
matmul(k);
}
slice_iters--;
if (slice_iters == 0) break;
}
a_gl_rd += a_gl_rd_delta_o * stages;
// Process results and, if necessary, proceed to the next column slice.
// While this pattern may not be the most readable, other ways of writing
// the loop seemed to noticeably worse performance after compilation.
if (slice_iters == 0) {
cp_async_wait<0>();
bool last = slice_idx == slice_count - 1;
// For per-column scales, we only fetch them here in the final step before
// write-out
if (group_blocks == -1 && last) {
if (s_sh_wr_pred) cp_async4(&sh_s[s_sh_wr], &s[s_gl_rd]);
cp_async_fence();
}
thread_block_reduce();
if (group_blocks == -1 && last) {
cp_async_wait<0>();
__syncthreads();
if (threadIdx.x / 32 < thread_n_blocks / 4) {
reinterpret_cast<int4*>(&frag_s)[0] = sh_s[s_sh_rd + 0];
reinterpret_cast<int4*>(&frag_s)[1] = sh_s[s_sh_rd + 4];
}
}
if (slice_count > 1) { // only globally reduce if there is more than one
// block in a slice
barrier_acquire(&locks[slice_col], slice_idx);
global_reduce(slice_idx == 0, last);
barrier_release(&locks[slice_col], last);
}
if (last) // only the last block in a slice actually writes the result
write_result();
slice_row = 0;
slice_col_par++;
slice_col++;
init_slice();
if (slice_iters) {
a_gl_rd = a_gl_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++)
B_ptr[i] += b_sh_stride - b_gl_rd_delta_o * k_tiles;
if (slice_col == 0) {
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) B_ptr[i] -= b_gl_stride;
}
s_gl_rd = s_sh_stride * slice_col + threadIdx.x;
start_pipes();
}
}
}
}
#else
template <const int threads, // number of threads in a threadblock
const int thread_m_blocks, // number of 16x16 blocks in the m
// dimension (batchsize) of the
// threadblock
const int thread_n_blocks, // same for n dimension (output)
const int thread_k_blocks, // same for k dimension (reduction)
const int stages, // number of stages for the async global->shared
// fetch pipeline
const int group_blocks = -1 // number of consecutive 16x16 blocks
// with a separate quantization scale
>
__global__ void Marlin(
const int4* __restrict__ A, // fp16 input matrix of shape mxk
const int4* __restrict__ B, // 4bit quantized weight matrix of shape kxn
int4* __restrict__ C, // fp16 output buffer of shape mxn
const int4* __restrict__ s, // fp16 quantization scales of shape
// (k/groupsize)xn
int prob_m, // batch dimension m
int prob_n, // output dimension n
int prob_k, // reduction dimension k
int* locks // extra global storage for barrier synchronization
) {
// Marlin is not implemented yet for SM < 8.0
assert(false);
return;
}
#endif
// 8 warps are a good choice since every SM has 4 schedulers and having more
// than 1 warp per schedule allows some more latency hiding. At the same time,
// we want relatively few warps to have many registers per warp and small tiles.
const int USER_THREADS =
256; // Note: This is only used with user-provided thread_k/n
const int STAGES = 4; // 4 pipeline stages fit into shared memory
const int SHARED_MEM =
96 * 1024; // max shared memory on compute capability 8.6 (< 8.0)
static constexpr int min_thread_n = 64;
static constexpr int min_thread_k = 64;
static constexpr int tile_size = 16;
static constexpr int max_par = 16;
static constexpr int pack_factor_4bit =
8; // We have 8 4-bit vals inside a 32 bit
#define __CALL_IF(THREAD_M_BLOCKS, THREAD_N_BLOCKS, THREAD_K_BLOCKS, \
GROUP_BLOCKS, NUM_THREADS) \
else if (thread_m_blocks == THREAD_M_BLOCKS && \
thread_n_blocks == THREAD_N_BLOCKS && \
thread_k_blocks == THREAD_K_BLOCKS && \
group_blocks == GROUP_BLOCKS && num_threads == NUM_THREADS) { \
cudaFuncSetAttribute(Marlin<NUM_THREADS, THREAD_M_BLOCKS, THREAD_N_BLOCKS, \
THREAD_K_BLOCKS, STAGES, GROUP_BLOCKS>, \
cudaFuncAttributeMaxDynamicSharedMemorySize, \
SHARED_MEM); \
Marlin<NUM_THREADS, THREAD_M_BLOCKS, THREAD_N_BLOCKS, THREAD_K_BLOCKS, \
STAGES, GROUP_BLOCKS><<<blocks, NUM_THREADS, SHARED_MEM, stream>>>( \
A_ptr, B_ptr, C_ptr, s_ptr, prob_m, prob_n, prob_k, locks); \
}
typedef struct {
int thread_k;
int thread_n;
int num_threads;
} thread_config_t;
thread_config_t small_batch_thread_configs[] = {
// Ordered by priority
// thread_k, thread_n, num_threads
{128, 128, 256}, // Default
{128, 64, 128}, // Reduce N 2X, same K
{64, 256, 256}, // Reduce K 2X, increase N 2X
{64, 128, 128}, // Reduce K 2X, same N
};
thread_config_t large_batch_thread_configs[] = {
// Ordered by priority
// thread_k, thread_n, num_threads
{64, 256, 256}, // Default
{128, 128, 256}, // Reduce N 2X, increase K 2X
{64, 128, 128}, // Reduce N 2X, same K
{128, 64, 128}, // Reduce N 4X, increase K 2X
};
bool is_valid_config(thread_config_t const& th_config, int prob_m, int prob_n,
int prob_k) {
// Sanity
if (th_config.thread_k == -1 || th_config.thread_n == -1 ||
th_config.num_threads == -1) {
return false;
}
// Verify K/N are divisible by thread K/N
if (prob_k % th_config.thread_k != 0 || prob_n % th_config.thread_n != 0) {
return false;
}
// thread_k can be only 128 or 64 (because it must be less than groupsize
// which is 128)
if (th_config.thread_k != 128 && th_config.thread_k != 64) {
return false;
}
// Verify min for thread K/N
if (th_config.thread_n < min_thread_n || th_config.thread_k < min_thread_k) {
return false;
}
// num_threads must be at least 128 (= 4 warps)
if (th_config.num_threads < 128) {
return false;
}
return true;
}
thread_config_t determine_thread_config(int prob_m, int prob_n, int prob_k) {
if (prob_m <= 16) {
for (auto th_config : small_batch_thread_configs) {
if (is_valid_config(th_config, prob_m, prob_n, prob_k)) {
return th_config;
}
}
} else {
for (auto th_config : large_batch_thread_configs) {
if (is_valid_config(th_config, prob_m, prob_n, prob_k)) {
return th_config;
}
}
}
return thread_config_t{-1, -1, -1};
}
#define CALL_IF(N_BLOCKS, K_BLOCKS, NUM_THREADS) \
__CALL_IF(1, N_BLOCKS, K_BLOCKS, -1, NUM_THREADS) \
__CALL_IF(1, N_BLOCKS, K_BLOCKS, 8, NUM_THREADS) \
__CALL_IF(1, N_BLOCKS, K_BLOCKS, -1, NUM_THREADS) \
__CALL_IF(1, N_BLOCKS, K_BLOCKS, 8, NUM_THREADS) \
__CALL_IF(2, N_BLOCKS, K_BLOCKS, -1, NUM_THREADS) \
__CALL_IF(2, N_BLOCKS, K_BLOCKS, 8, NUM_THREADS) \
__CALL_IF(3, N_BLOCKS, K_BLOCKS, -1, NUM_THREADS) \
__CALL_IF(3, N_BLOCKS, K_BLOCKS, 8, NUM_THREADS) \
__CALL_IF(4, N_BLOCKS, K_BLOCKS, -1, NUM_THREADS) \
__CALL_IF(4, N_BLOCKS, K_BLOCKS, 8, NUM_THREADS)
void marlin_cuda(const void* A, const void* B, void* C, void* s, int prob_m,
int prob_n, int prob_k, void* workspace, int groupsize = -1,
int dev = 0, cudaStream_t stream = 0, int thread_k = -1,
int thread_n = -1, int sms = -1, int max_par = 16) {
int tot_m = prob_m;
int tot_m_blocks = ceildiv(tot_m, 16);
int pad = 16 * tot_m_blocks - tot_m;
if (sms == -1)
cudaDeviceGetAttribute(&sms, cudaDevAttrMultiProcessorCount, dev);
// Set thread config
thread_config_t th_config;
if (thread_k != -1 && thread_n != -1) {
// User-defined config
th_config = thread_config_t{thread_k, thread_n, USER_THREADS};
} else {
// Auto config
th_config = determine_thread_config(prob_m, prob_n, prob_k);
}
if (!is_valid_config(th_config, prob_m, prob_n, prob_k)) {
throw std::runtime_error(
"Invalid thread config: thread_k = " + str(th_config.thread_k) +
", thread_n = " + str(th_config.thread_n) +
", num_threads = " + str(th_config.num_threads) + " for MKN = [" +
str(prob_m) + ", " + str(prob_k) + ", " + str(prob_n) + "]");
}
// Uncomment for debug
// std::cout << "Using thread_config: thread_k = " + str(th_config.thread_k) +
// ", thread_n = " + str(th_config.thread_n) +
// ", num_threads = " + str(th_config.num_threads) + " for
// MKN = [" + str(prob_m) +
// ", " + str(prob_k) + ", " + str(prob_n) + "]\n";
int num_threads = th_config.num_threads;
thread_k = th_config.thread_k;
thread_n = th_config.thread_n;
int thread_k_blocks = thread_k / 16;
int thread_n_blocks = thread_n / 16;
int group_blocks = (groupsize == -1) ? -1 : groupsize / 16;
int blocks = sms;
if (prob_m == 0 || prob_n == 0 || prob_k == 0) {
return;
}
TORCH_CHECK(prob_n % thread_n == 0, "prob_n = ", prob_n,
" is not divisible by thread_n = ", thread_n);
TORCH_CHECK(prob_k % thread_k == 0, "prob_k = ", prob_k,
" is not divisible by thread_k = ", thread_k);
if (group_blocks != -1) {
TORCH_CHECK(prob_k % group_blocks == 0, "prob_k = ", prob_k,
" is not divisible by group_blocks = ", group_blocks);
}
const int4* A_ptr = (const int4*)A;
const int4* B_ptr = (const int4*)B;
int4* C_ptr = (int4*)C;
const int4* s_ptr = (const int4*)s;
int* locks = (int*)workspace;
for (int i = 0; i < tot_m_blocks; i += 4) {
int thread_m_blocks = tot_m_blocks - i;
prob_m = tot_m - 16 * i;
int par = 1;
if (thread_m_blocks > 4) {
// Note that parallel > 1 currently only works for inputs without any
// padding
par = (16 * thread_m_blocks - pad) / 64;
if (par > max_par) par = max_par;
prob_m = 64 * par;
i += 4 * (par - 1);
thread_m_blocks = 4;
}
// For compilation speed, we only define the kernel configurations that have
// seemed useful (in terms of performance) in our testing, however many more
// are, in principle, possible.
if (false) {
}
CALL_IF(8, 8, 256)
CALL_IF(16, 4, 256)
CALL_IF(8, 4, 128)
CALL_IF(4, 8, 128)
else {
throw std::runtime_error("Unsupported shapes: MKN = [" + str(prob_m) +
", " + str(prob_k) + ", " + str(prob_n) + "]" +
", groupsize = " + str(groupsize) +
", thread_m_blocks = " + str(thread_m_blocks) +
", thread_n_blocks = " + str(thread_n_blocks) +
", thread_k_blocks = " + str(thread_k_blocks));
}
A_ptr += 16 * thread_m_blocks * (prob_k / 8) * par;
C_ptr += 16 * thread_m_blocks * (prob_n / 8) * par;
}
}
} // namespace marlin
torch::Tensor marlin_gemm(torch::Tensor& a, torch::Tensor& b_q_weight,
torch::Tensor& b_scales, torch::Tensor& workspace,
int64_t size_m, int64_t size_n, int64_t size_k) {
// Verify M
TORCH_CHECK(size_m == a.size(0),
"Shape mismatch: a.size(0) = " + str(a.size(0)) +
", size_m = " + str(size_m));
// Verify K
TORCH_CHECK(size_k == a.size(1),
"Shape mismatch: a.size(1) = " + str(a.size(1)) +
", size_k = " + str(size_k));
TORCH_CHECK(size_k % marlin::tile_size == 0,
"size_k = " + str(size_k) +
" is not divisible by tile_size = " + str(marlin::tile_size));
TORCH_CHECK((size_k / marlin::tile_size) == b_q_weight.size(0),
"Shape mismatch: b_q_weight.size(0) = " +
str(b_q_weight.size(0)) + ", size_k = " + str(size_k) +
", tile_size = " + str(marlin::tile_size));
// Verify N
TORCH_CHECK(b_scales.size(1) == size_n,
"b_scales.size(1) = " + str(b_scales.size(1)) +
", size_n = " + str(size_n));
TORCH_CHECK(b_q_weight.size(1) % marlin::tile_size == 0,
"b_q_weight.size(1) = " + str(b_q_weight.size(1)) +
" is not divisible by tile_size = " + str(marlin::tile_size));
int actual_size_n =
(b_q_weight.size(1) / marlin::tile_size) * marlin::pack_factor_4bit;
TORCH_CHECK(
size_n == actual_size_n,
"size_n = " + str(size_n) + ", actual_size_n = " + str(actual_size_n));
// Verify A device and strides
TORCH_CHECK(a.device().is_cuda(), "A is not on GPU");
TORCH_CHECK(a.is_contiguous(), "A is not contiguous");
// Verify B device and strides
TORCH_CHECK(b_q_weight.device().is_cuda(), "b_q_weight is not on GPU");
TORCH_CHECK(b_q_weight.is_contiguous(), "b_q_weight is not contiguous");
// Verify scales device and strides
TORCH_CHECK(b_scales.device().is_cuda(), "b_scales is not on GPU");
TORCH_CHECK(b_scales.is_contiguous(), "b_scales is not contiguous");
// Alloc C matrix
const at::cuda::OptionalCUDAGuard device_guard(device_of(a));
auto options = torch::TensorOptions().dtype(a.dtype()).device(a.device());
torch::Tensor c = torch::empty({size_m, size_n}, options);
// thread_k: `k` size of a thread_tile in `weights` (can usually be left as
// auto -1)
int thread_k = -1;
// thread_n: `n` size of a thread_tile in `weights` (can usually be left as
// auto -1)
int thread_n = -1;
// sms: number of SMs to use for the kernel (can usually be left as auto -1)
int sms = -1;
// Detect groupsize
if (b_scales.size(0) != 1) {
TORCH_CHECK(size_k % b_scales.size(0) == 0,
"size_k = " + str(size_k) +
", is not divisible by b_scales.size(0) = " +
str(b_scales.size(0)));
}
int groupsize = b_scales.size(0) == 1 ? -1 : size_k / b_scales.size(0);
// Verify groupsize
TORCH_CHECK(groupsize == -1 || groupsize == 128,
"Unexpected groupsize = " + str(groupsize));
// Verify workspace size
TORCH_CHECK(
size_n % marlin::min_thread_n == 0,
"size_n = " + str(size_n) +
", is not divisible by min_thread_n = " + str(marlin::min_thread_n));
int min_workspace_size = (size_n / marlin::min_thread_n) * marlin::max_par;
TORCH_CHECK(workspace.numel() >= min_workspace_size,
"workspace.numel = " + str(workspace.numel()) +
" is below min_workspace_size = " + str(min_workspace_size));
int dev = a.get_device();
marlin::marlin_cuda(a.data_ptr(), b_q_weight.data_ptr(), c.data_ptr(),
b_scales.data_ptr(), size_m, size_n, size_k,
workspace.data_ptr(), groupsize, dev,
at::cuda::getCurrentCUDAStream(dev), thread_k, thread_n,
sms, marlin::max_par);
return c;
}
server/marlin/marlin_kernels/sparse/common/base.h deleted 100644 → 0
View file @ 9822d7f6
/*
* Copyright (C) 2024 Roberto Lopez Castro (roberto.lopez.castro@udc.es). 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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.
*/
#pragma once
namespace marlin_24 {
constexpr int ceildiv(int a, int b) { return (a + b - 1) / b; }
// Instances of `Vec` are used to organize groups of >>registers<<, as needed
// for instance as inputs to tensor core operations. Consequently, all
// corresponding index accesses must be compile-time constants, which is why we
// extensively use `#pragma unroll` throughout the kernel code to guarantee
// this.
template <typename T, int n>
struct Vec {
T elems[n];
__device__ T& operator[](int i) { return elems[i]; }
};
template <int M_, int N_, int K_>
struct ShapeBase {
static constexpr int M = M_, N = N_, K = K_;
};
using I4 = Vec<int, 4>;
// Matrix fragments for tensor core instructions; their precise layout is
// documented here:
// https://docs.nvidia.com/cuda/parallel-thread-execution/index.html#matrix-fragments-for-mma-m16n8k16-with-floating-point-type
using FragA = Vec<half2, 4>;
using FragB = Vec<half2, 2>;
using FragM = Vec<uint, 1>;
using FragC = Vec<float, 4>;
using FragS = Vec<half2, 1>; // quantization scales
} // namespace marlin_24
server/marlin/marlin_kernels/sparse/common/mem.h deleted 100644 → 0
View file @ 9822d7f6
/*
* Copyright (C) 2024 Roberto Lopez Castro (roberto.lopez.castro@udc.es). 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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.
*/
#pragma once
#include "base.h"
namespace marlin_24 {
// Predicated asynchronous global->shared copy; used for inputs A where we apply
// predication to handle batchsizes that are not multiples of 16.
__device__ inline void cp_async4_pred_zfill(void* smem_ptr,
const void* glob_ptr,
bool pred = true,
const bool zfill = false) {
const int BYTES = 16;
int src_in_bytes = (zfill ? 0 : BYTES);
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile(
"{\n"
" .reg .pred p;\n"
" setp.ne.b32 p, %0, 0;\n"
" @p cp.async.cg.shared.global [%1], [%2], %3;\n"
"}\n" ::"r"((int)pred),
"r"(smem), "l"(glob_ptr), "n"(BYTES), "r"(src_in_bytes));
}
__device__ inline void cp_async4_pred(void* smem_ptr, const void* glob_ptr,
bool pred = true) {
const int BYTES = 16;
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile(
"{\n"
" .reg .pred p;\n"
" setp.ne.b32 p, %0, 0;\n"
" @p cp.async.cg.shared.global [%1], [%2], %3;\n"
"}\n" ::"r"((int)pred),
"r"(smem), "l"(glob_ptr), "n"(BYTES));
}
// Asynchronous global->shared copy
__device__ inline void cp_async4(void* smem_ptr, const void* glob_ptr) {
const int BYTES = 16;
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile(
"{\n"
" cp.async.cg.shared.global [%0], [%1], %2;\n"
"}\n" ::"r"(smem),
"l"(glob_ptr), "n"(BYTES));
}
// Async copy fence.
__device__ inline void cp_async_fence() {
asm volatile("cp.async.commit_group;\n" ::);
}
// Wait until at most `n` async copy stages are still pending.
template <int n>
__device__ inline void cp_async_wait() {
asm volatile("cp.async.wait_group %0;\n" ::"n"(n));
}
// Instruction for loading a full 16x16 matrix fragment of operand A from shared
// memory, directly in tensor core layout.
__device__ inline void ldsm4(FragA& frag_a, const void* smem_ptr) {
uint32_t* a = reinterpret_cast<uint32_t*>(&frag_a);
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile("ldmatrix.sync.aligned.m8n8.x4.shared.b16 {%0,%1,%2,%3}, [%4];\n"
: "=r"(a[0]), "=r"(a[1]), "=r"(a[2]), "=r"(a[3])
: "r"(smem));
}
__device__ inline void ldsm4_m(FragM& frag_m, const void* smem_ptr) {
uint32_t* a = reinterpret_cast<uint32_t*>(&frag_m);
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile("ldmatrix.sync.aligned.m8n8.x2.shared.b16 {%0,%1}, [%2];\n"
: "=r"(a[0]), "=r"(a[1])
: "r"(smem));
}
// Instruction for loading a full 16x16 matrix fragment of operand A from shared
// memory, directly in tensor core layout.
__device__ inline void ldsm4_t(FragA& frag_a, const void* smem_ptr) {
uint32_t* a = reinterpret_cast<uint32_t*>(&frag_a);
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
asm volatile(
"ldmatrix.sync.aligned.m8n8.x4.trans.shared.b16 {%0,%1,%2,%3}, [%4];\n"
: "=r"(a[0]), "=r"(a[1]), "=r"(a[2]), "=r"(a[3])
: "r"(smem));
}
// Wait until barrier reaches `count`, then lock for current threadblock.
__device__ inline void barrier_acquire(int* lock, int count) {
if (threadIdx.x == 0) {
int state = -1;
do
// Guarantee that subsequent writes by this threadblock will be visible
// globally.
asm volatile("ld.global.acquire.gpu.b32 %0, [%1];\n"
: "=r"(state)
: "l"(lock));
while (state != count);
}
__syncthreads();
}
// Release barrier and increment visitation count.
__device__ inline void barrier_release(int* lock, bool reset = false) {
__syncthreads();
if (threadIdx.x == 0) {
if (reset) {
lock[0] = 0;
return;
}
int val = 1;
// Make sure that all writes since acquiring this barrier are visible
// globally, while releasing the barrier.
asm volatile("fence.acq_rel.gpu;\n");
asm volatile("red.relaxed.gpu.global.add.s32 [%0], %1;\n"
:
: "l"(lock), "r"(val));
}
}
} // namespace marlin_24
server/marlin/marlin_kernels/sparse/common/mma.h deleted 100644 → 0
View file @ 9822d7f6
/*
* Copyright (C) 2024 Roberto Lopez Castro (roberto.lopez.castro@udc.es). 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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.
*/
#pragma once
#include "base.h"
#include <cudaTypedefs.h>
namespace marlin_24 {
// On CUDA earlier than 12.5, the ordered_metadata version of this instruction
// is not supported. On later versions of CUDA the version without ordered
// metadata results in the following warning:
// | Advisory: Modifier ‘.sp::ordered_metadata’ should be used on instruction
// | ‘mma’ instead of modifier ‘.sp’ as it is expected to have substantially
// | reduced performance on some future architectures
#if defined CUDA_VERSION && CUDA_VERSION >= 12050
#define MMA_SP_INST \
"mma.sp::ordered_metadata.sync.aligned.m16n8k32.row.col.f32.f16.f16.f32 "
#else
#define MMA_SP_INST "mma.sp.sync.aligned.m16n8k32.row.col.f32.f16.f16.f32 "
#endif
// m16n8k32 sparse tensor core mma instruction with fp16 inputs and fp32
// output/accumulation.
__device__ inline void mma_sp(const FragB& a_frag0, const FragB& a_frag1,
const FragA& frag_b, FragC& frag_c, FragM& frag_m,
const int psel) {
const uint32_t* a0 = reinterpret_cast<const uint32_t*>(&a_frag0);
const uint32_t* a1 = reinterpret_cast<const uint32_t*>(&a_frag1);
const uint32_t* b = reinterpret_cast<const uint32_t*>(&frag_b);
const uint32_t* e = reinterpret_cast<const uint32_t*>(&frag_m);
float* c = reinterpret_cast<float*>(&frag_c);
if (psel == 0) {
asm volatile(MMA_SP_INST
"{%0, %1, %2, %3}, {%4, %5, %6, %7}, {%8, %9, %10,%11}, "
"{%12,%13,%14,%15}, %16, 0x0;\n"
: "=f"(c[0]), "=f"(c[1]), "=f"(c[2]), "=f"(c[3])
: "r"(a0[0]), "r"(a1[0]), "r"(a0[1]), "r"(a1[1]), "r"(b[0]),
"r"(b[2]), "r"(b[4]), "r"(b[6]), "f"(c[0]), "f"(c[1]),
"f"(c[2]), "f"(c[3]), "r"(e[0]));
asm volatile(MMA_SP_INST
"{%0, %1, %2, %3}, {%4, %5, %6, %7}, {%8, %9, %10,%11}, "
"{%12,%13,%14,%15}, %16, 0x0;\n"
: "=f"(c[4]), "=f"(c[5]), "=f"(c[6]), "=f"(c[7])
: "r"(a0[0]), "r"(a1[0]), "r"(a0[1]), "r"(a1[1]), "r"(b[1]),
"r"(b[3]), "r"(b[5]), "r"(b[7]), "f"(c[4]), "f"(c[5]),
"f"(c[6]), "f"(c[7]), "r"(e[0]));
} else {
asm volatile(MMA_SP_INST
"{%0, %1, %2, %3}, {%4, %5, %6, %7}, {%8, %9, %10,%11}, "
"{%12,%13,%14,%15}, %16, 0x1;\n"
: "=f"(c[0]), "=f"(c[1]), "=f"(c[2]), "=f"(c[3])
: "r"(a0[0]), "r"(a1[0]), "r"(a0[1]), "r"(a1[1]), "r"(b[0]),
"r"(b[2]), "r"(b[4]), "r"(b[6]), "f"(c[0]), "f"(c[1]),
"f"(c[2]), "f"(c[3]), "r"(e[0]));
asm volatile(MMA_SP_INST
"{%0, %1, %2, %3}, {%4, %5, %6, %7}, {%8, %9, %10,%11}, "
"{%12,%13,%14,%15}, %16, 0x1;\n"
: "=f"(c[4]), "=f"(c[5]), "=f"(c[6]), "=f"(c[7])
: "r"(a0[0]), "r"(a1[0]), "r"(a0[1]), "r"(a1[1]), "r"(b[1]),
"r"(b[3]), "r"(b[5]), "r"(b[7]), "f"(c[4]), "f"(c[5]),
"f"(c[6]), "f"(c[7]), "r"(e[0]));
}
}
// Lookup-table based 3-input logical operation; explicitly used for
// dequantization as the compiler does not seem to automatically recognize it in
// all cases.
template <int lut>
__device__ inline int lop3(int a, int b, int c) {
int res;
asm volatile("lop3.b32 %0, %1, %2, %3, %4;\n"
: "=r"(res)
: "r"(a), "r"(b), "r"(c), "n"(lut));
return res;
}
__device__ __forceinline__ uint2 to_half4(float c0, float c1, float c2,
float c3) {
uint2 r;
asm("{\n\t"
".reg .f16 a, b, c, d; \n\t"
"cvt.rn.f16.f32 a, %2; \n\t"
"cvt.rn.f16.f32 b, %3; \n\t"
"cvt.rn.f16.f32 c, %4; \n\t"
"cvt.rn.f16.f32 d, %5; \n\t"
"mov.b32 %0, {a, b}; \n\t"
"mov.b32 %1, {c, d}; \n\t"
"}"
: "=r"(r.x), "=r"(r.y)
: "f"(c0), "f"(c1), "f"(c2), "f"(c3));
return r;
}
// Constructs destination register by taking bytes from 2 sources (based on
// mask)
template <int start_byte, int mask>
__device__ inline uint32_t prmt(uint32_t a) {
uint32_t res;
asm volatile("prmt.b32 %0, %1, %2, %3;\n"
: "=r"(res)
: "r"(a), "n"(start_byte), "n"(mask));
return res;
}
// Efficiently dequantize an int32 value into a full B-fragment of 4 fp16
// values. We mostly follow the strategy in the link below, with some small
// changes:
// https://github.com/NVIDIA/FasterTransformer/blob/main/src/fastertransformer/cutlass_extensions/include/cutlass_extensions/interleaved_numeric_conversion.h
__device__ inline FragB dequant_4bit(int q) {
const int LO = 0x000f000f;
const int HI = 0x00f000f0;
const int EX = 0x64006400;
// Guarantee that the `(a & b) | c` operations are LOP3s.
int lo = lop3<(0xf0 & 0xcc) | 0xaa>(q, LO, EX);
int hi = lop3<(0xf0 & 0xcc) | 0xaa>(q, HI, EX);
// We want signed int4 outputs, hence we fuse the `-8` symmetric zero point
// directly into `SUB` and `ADD`.
const int SUB = 0x64086408;
const int MUL = 0x2c002c00;
const int ADD = 0xd480d480;
FragB frag_b;
frag_b[0] = __hsub2(*reinterpret_cast<half2*>(&lo),
*reinterpret_cast<const half2*>(&SUB));
frag_b[1] = __hfma2(*reinterpret_cast<half2*>(&hi),
*reinterpret_cast<const half2*>(&MUL),
*reinterpret_cast<const half2*>(&ADD));
return frag_b;
}
// Efficiently dequantize an int32 value into a full B-fragment of 4 fp16
// values. We mostly follow the strategy in the link below, with some small
// changes:
// https://github.com/NVIDIA/FasterTransformer/blob/main/src/fastertransformer/cutlass_extensions/include/cutlass_extensions/interleaved_numeric_conversion.h
__device__ inline FragB dequant_8bit(int q) {
static constexpr uint32_t mask_for_elt_01 = 0x5250;
static constexpr uint32_t mask_for_elt_23 = 0x5351;
static constexpr uint32_t start_byte_for_fp16 = 0x64646464;
uint32_t lo = prmt<start_byte_for_fp16, mask_for_elt_01>(q);
uint32_t hi = prmt<start_byte_for_fp16, mask_for_elt_23>(q);
static constexpr uint32_t I8s_TO_F16s_MAGIC_NUM = 0x64806480;
FragB frag_b;
frag_b[0] = __hsub2(*reinterpret_cast<half2*>(&lo),
*reinterpret_cast<const half2*>(&I8s_TO_F16s_MAGIC_NUM));
frag_b[1] = __hsub2(*reinterpret_cast<half2*>(&hi),
*reinterpret_cast<const half2*>(&I8s_TO_F16s_MAGIC_NUM));
return frag_b;
}
// Multiply dequantized values by the corresponding quantization scale; used
// only for grouped quantization.
__device__ inline void scale(FragB& frag_b, FragS& frag_s, int i) {
half2 s = __half2half2(reinterpret_cast<__half*>(&frag_s)[i]);
frag_b[0] = __hmul2(frag_b[0], s);
frag_b[1] = __hmul2(frag_b[1], s);
}
__device__ inline void scale_floats(float* c0, float* c1, float* c2, float* c3,
FragS& s0, float* c4, float* c5, float* c6,
float* c7, FragS& s1) {
*c0 = __fmul_rn(*c0, __half2float(s0[0].x));
*c1 = __fmul_rn(*c1, __half2float(s0[0].y));
*c2 = __fmul_rn(*c2, __half2float(s0[1].x));
*c3 = __fmul_rn(*c3, __half2float(s0[1].y));
*c4 = __fmul_rn(*c4, __half2float(s1[0].x));
*c5 = __fmul_rn(*c5, __half2float(s1[0].y));
*c6 = __fmul_rn(*c6, __half2float(s1[1].x));
*c7 = __fmul_rn(*c7, __half2float(s1[1].y));
}
} // namespace marlin_24
server/marlin/marlin_kernels/sparse/marlin_24_cuda_kernel.cu deleted 100644 → 0
View file @ 9822d7f6
/*
* Notice: This file was modified by Neuralmagic inc to include 8-bit support
*
* Copyright (C) 2024 Roberto Lopez Castro (roberto.lopez.castro@udc.es). 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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 <torch/all.h>
#include <ATen/cuda/CUDAContext.h>
#include <c10/cuda/CUDAGuard.h>
#include <cuda.h>
#include <cuda_fp16.h>
#include <cuda_runtime.h>
#include <iostream>
#include "common/base.h"
#if defined(__CUDA_ARCH__) && __CUDA_ARCH__ < 800
#else
#include "common/mem.h"
#include "common/mma.h"
#endif
template <typename T>
inline std::string str(T x) {
return std::to_string(x);
}
namespace marlin_24 {
// 8 warps are a good choice since every SM has 4 schedulers and having more
// than 1 warp per schedule allows some more latency hiding. At the same time,
// we want relatively few warps to have many registers per warp and small tiles.
static constexpr int THREADS = 256;
static constexpr int STAGES = 4;
static constexpr int min_thread_n = 128;
static constexpr int tile_size = 16;
static constexpr int max_par = 64;
#if defined(__CUDA_ARCH__) && __CUDA_ARCH__ < 800
template <const int num_bits, // weight bits
const int threads, // number of threads in a threadblock
const int thread_m_blocks, // number of 16x16 blocks in the m
// dimension (batchsize) of the
// threadblock
const int thread_n_blocks, // same for n dimension (output)
const int thread_k_blocks, // same for k dimension (reduction)
const int stages, // number of stages for the async global->shared
// fetch pipeline
const int group_blocks = -1 // number of consecutive 16x16 blocks
// with a separate quantization scale
>
__global__ void Marlin_24(
const int4* __restrict__ A, // fp16 input matrix of shape mxk
const int4* __restrict__ B, // 4bit quantized weight matrix of shape kxn
const int4* __restrict__ meta, // 2bit metadata information about 2:4
// format on B
int4* __restrict__ C, // fp16 output buffer of shape mxn
const int4* __restrict__ s, // fp16 quantization scales of shape
// (k/groupsize)xn
int prob_m, // batch dimension m
int prob_n, // output dimension n
int prob_k, // reduction dimension k
int* locks // extra global storage for barrier synchronization
) {}
torch::Tensor gptq_marlin_24_gemm(torch::Tensor& a, torch::Tensor& b_q_weight,
torch::Tensor& b_meta,
torch::Tensor& b_scales,
torch::Tensor& workspace, int64_t num_bits,
int64_t size_m, int64_t size_n,
int64_t size_k) {
TORCH_CHECK_NOT_IMPLEMENTED(
false, "gptq_marlin_24_gemm(..) requires CUDA_ARCH >= 8.0");
return torch::empty({1, 1});
}
#else
template <const int num_bits, // weight bits
const int threads, // number of threads in a threadblock
const int thread_m_blocks, // number of 16x16 blocks in the m
// dimension (batchsize) of the
// threadblock
const int thread_n_blocks, // same for n dimension (output)
const int thread_k_blocks, // same for k dimension (reduction)
const int stages, // number of stages for the async global->shared
// fetch pipeline
const int group_blocks = -1 // number of consecutive 16x16 blocks
// with a separate quantization scale
>
__global__ void Marlin_24(
const int4* __restrict__ A, // fp16 input matrix of shape mxk
const int4* __restrict__ B, // 4bit quantized weight matrix of shape kxn
const int4* __restrict__ meta, // 2bit metadata information about 2:4
// format on B
int4* __restrict__ C, // fp16 output buffer of shape mxn
const int4* __restrict__ s, // fp16 quantization scales of shape
// (k/groupsize)xn
int prob_m, // batch dimension m
int prob_n, // output dimension n
int prob_k, // reduction dimension k
int* locks // extra global storage for barrier synchronization
) {
// Each threadblock processes one "stripe" of the B matrix with (roughly) the
// same size, which might involve multiple column "slices" (of width 16 *
// `thread_n_blocks`). Stripes are defined as shown in the 3x3 matrix 5 SM
// example:
// 0 1 3
// 0 2 3
// 1 2 4
// While this kind of partitioning makes things somewhat more complicated, it
// ensures good utilization of all SMs for many kinds of shape and GPU
// configurations, while requiring as few slow global cross-threadblock
// reductions as possible.
// For larger GEMMs we run multiple batchsize 64 versions in parallel for a
// better partitioning with less reductions
int parallel = 1;
if (prob_m > 16 * thread_m_blocks) {
parallel = prob_m / (16 * thread_m_blocks);
prob_m = 16 * thread_m_blocks;
}
// number of thread_k_blocks in k-dim
int k_tiles = prob_k / 32 / thread_k_blocks;
// number of thread_n_blocks in n-dim
int n_tiles = prob_n / 16 / thread_n_blocks;
// iters needed to cover all slices
int iters = ceildiv(k_tiles * n_tiles * parallel, gridDim.x);
// Ensure that the number of tiles in each stripe is a multiple of the
// groupsize; this avoids an annoying special case where a stripe starts in
// the middle of group.
if (group_blocks != -1)
iters = (group_blocks / thread_k_blocks) *
ceildiv(iters, (group_blocks / thread_k_blocks));
int slice_row = (iters * blockIdx.x) % k_tiles;
int slice_col_par = (iters * blockIdx.x) / k_tiles;
int slice_col = slice_col_par;
// number of threadblock tiles in the current slice
int slice_iters;
// total number of active threadblocks in the current slice
int slice_count = 0;
// index of threadblock in current slice; numbered bottom to top
int slice_idx;
// We can easily implement parallel problem execution by just remapping
// indices and advancing global pointers
if (slice_col_par >= n_tiles) {
A += (slice_col_par / n_tiles) * 16 * thread_m_blocks * prob_k / 8;
C += (slice_col_par / n_tiles) * 16 * thread_m_blocks * prob_n / 8;
locks += (slice_col_par / n_tiles) * n_tiles;
slice_col = slice_col_par % n_tiles;
}
// Compute all information about the current slice which is required for
// synchronization.
auto init_slice = [&]() {
slice_iters =
iters * (blockIdx.x + 1) - (k_tiles * slice_col_par + slice_row);
if (slice_iters < 0 || slice_col_par >= n_tiles * parallel) slice_iters = 0;
if (slice_iters == 0) return;
if (slice_row + slice_iters > k_tiles) slice_iters = k_tiles - slice_row;
slice_count = 1;
slice_idx = 0;
int col_first = iters * ceildiv(k_tiles * slice_col_par, iters);
if (col_first <= k_tiles * (slice_col_par + 1)) {
int col_off = col_first - k_tiles * slice_col_par;
slice_count = ceildiv(k_tiles - col_off, iters);
if (col_off > 0) slice_count++;
int delta_first = iters * blockIdx.x - col_first;
if (delta_first < 0 || (col_off == 0 && delta_first == 0))
slice_idx = slice_count - 1;
else {
slice_idx = slice_count - 1 - delta_first / iters;
if (col_off > 0) slice_idx--;
}
}
if (slice_col == n_tiles) {
A += 16 * thread_m_blocks * prob_k / 8;
C += 16 * thread_m_blocks * prob_n / 8;
locks += n_tiles;
slice_col = 0;
}
};
init_slice();
// RLC: 8 is vec_size -> 128-bit instructions, 8 fp16 elements
int a_gl_stride = prob_k / 8; // stride of the A matrix in global memory
// stride of an A matrix tile in shared memory
constexpr int a_sh_stride = 32 * thread_k_blocks / 8;
// delta between subsequent A tiles in global memory
constexpr int a_gl_rd_delta_o = 32 * thread_k_blocks / 8;
// between subsequent accesses within a tile
int a_gl_rd_delta_i = a_gl_stride * (threads / a_gl_rd_delta_o);
// between shared memory writes
constexpr int a_sh_wr_delta = a_sh_stride * (threads / a_gl_rd_delta_o);
// between shared memory tile reads //RLC: 2 * #warps k-dim
constexpr int a_sh_rd_delta_o = 4 * ((threads / 32) / (thread_n_blocks / 4));
// within a shared memory tile
constexpr int a_sh_rd_delta_i = a_sh_stride * 16;
// overall size of a tile
constexpr int a_sh_stage = a_sh_stride * (16 * thread_m_blocks);
// number of shared write iterations for a tile
constexpr int a_sh_wr_iters = ceildiv(a_sh_stage, a_sh_wr_delta);
constexpr int pack_factor = 32 / num_bits;
int b_gl_stride = 16 * prob_n / (pack_factor * 4);
constexpr int b_sh_stride = ((thread_n_blocks * 16) * 16 / pack_factor) / 4;
constexpr int b_thread_vecs = num_bits == 4 ? 1 : 2;
constexpr int b_sh_stride_threads = b_sh_stride / b_thread_vecs;
int b_gl_rd_delta_o = b_gl_stride * thread_k_blocks;
int b_gl_rd_delta_i = b_gl_stride * (threads / b_sh_stride_threads);
constexpr int b_sh_wr_delta = threads * b_thread_vecs;
constexpr int b_sh_rd_delta = threads * b_thread_vecs;
constexpr int b_sh_stage = b_sh_stride * thread_k_blocks;
constexpr int b_sh_wr_iters = b_sh_stage / b_sh_wr_delta;
int m_gl_stride = 2 * prob_n / 8; // (16*2*4 / 8) = 16
constexpr int m_sh_stride =
(16 * thread_n_blocks) / 4; // #warps n-dim * threads/warp
int m_gl_rd_delta_o = m_gl_stride * thread_k_blocks;
int m_gl_rd_delta_i = m_gl_stride * (threads / m_sh_stride);
constexpr int m_sh_wr_delta = threads / 2;
constexpr int m_sh_rd_delta = threads / 2;
constexpr int m_sh_stage = m_sh_stride * thread_k_blocks;
constexpr int m_sh_iters = ceildiv(m_sh_stage, m_sh_wr_delta);
int s_gl_stride = prob_n / 8;
constexpr int s_sh_stride = 16 * thread_n_blocks / 8;
constexpr int s_sh_stage = s_sh_stride;
int s_gl_rd_delta = s_gl_stride;
// Global A read index of current thread.
int a_gl_rd = a_gl_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
a_gl_rd += a_gl_rd_delta_o * slice_row;
// Shared write index of current thread.
int a_sh_wr = a_sh_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
// Shared read index.
int a_sh_rd =
a_sh_stride * ((threadIdx.x % 32) % 16) + (threadIdx.x % 32) / 16;
a_sh_rd += 4 * ((threadIdx.x / 32) / (thread_n_blocks / 4));
int b_gl_rd = b_gl_stride * (threadIdx.x / b_sh_stride_threads) +
(threadIdx.x % b_sh_stride_threads) * b_thread_vecs;
b_gl_rd += b_sh_stride * slice_col;
b_gl_rd += b_gl_rd_delta_o * slice_row;
int b_sh_wr = threadIdx.x * b_thread_vecs;
int b_sh_rd = threadIdx.x * b_thread_vecs;
int m_gl_rd = m_gl_stride * (threadIdx.x / (m_sh_stride)) +
(threadIdx.x % (m_sh_stride));
m_gl_rd += (m_sh_stride)*slice_col;
m_gl_rd += m_gl_rd_delta_o * slice_row;
int m_sh_wr = threadIdx.x;
int m_sh_rd = threadIdx.x % 16 + (threadIdx.x / 32) * 16;
int s_gl_rd;
if constexpr (group_blocks == -1) {
s_gl_rd = s_sh_stride * slice_col + threadIdx.x;
} else {
s_gl_rd = s_gl_stride * ((thread_k_blocks * slice_row) / group_blocks) +
s_sh_stride * slice_col + threadIdx.x;
}
int s_sh_wr = threadIdx.x;
int s_sh_rd;
// We use a different scale layout for grouped and column-wise quantization as
// we scale a `half2` tile in column-major layout in the former and in
// row-major in the latter case.
if (group_blocks != -1) {
s_sh_rd = 8 * ((threadIdx.x / 32) % (thread_n_blocks / 4)) +
(threadIdx.x % 32) / 4;
} else {
s_sh_rd = 8 * ((threadIdx.x / 32) % (thread_n_blocks / 4)) +
(threadIdx.x % 32) / 4;
}
// Precompute which thread should not read memory in which iterations; this is
// needed if there are more threads than required for a certain tilesize or
// when the batchsize is not a multiple of 16.
bool a_sh_wr_pred[a_sh_wr_iters];
#pragma unroll
for (int i = 0; i < a_sh_wr_iters; i++) {
a_sh_wr_pred[i] = a_sh_wr_delta * i + a_sh_wr < a_sh_stride * prob_m;
}
bool s_sh_wr_pred = threadIdx.x < s_sh_stride;
// To ensure that writing and reading A tiles to/from shared memory, the
// latter in fragment format, is fully bank conflict free, we need to use a
// rather fancy XOR-based layout. The key here is that neither reads nor
// writes of the 16-byte `int4` blocks of 8 consecutive threads involve the
// same shared memory banks. Further, it seems (based on NSight-Compute) that
// each warp must also write a consecutive memory segment?
auto transform_a = [&](int i) {
int row = i / a_gl_rd_delta_o;
return a_gl_rd_delta_o * row + (i % a_gl_rd_delta_o) ^ row;
};
// Since the computation of this remapping is non-trivial and, due to our main
// loop unrolls, all shared memory accesses are static, we simply precompute
// both transformed reads and writes.
int a_sh_wr_trans[a_sh_wr_iters];
#pragma unroll
for (int i = 0; i < a_sh_wr_iters; i++)
a_sh_wr_trans[i] = transform_a(a_sh_wr_delta * i + a_sh_wr);
int a_sh_rd_trans[2][b_sh_wr_iters][thread_m_blocks];
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) {
#pragma unroll
for (int j = 0; j < thread_m_blocks; j++) {
a_sh_rd_trans[0][i][j] =
transform_a(a_sh_rd_delta_o * i + a_sh_rd_delta_i * j + a_sh_rd);
a_sh_rd_trans[1][i][j] =
transform_a(a_sh_rd_delta_o * i + a_sh_rd_delta_i * j + a_sh_rd + 2);
}
}
// Since B-accesses have non-constant stride they have to be computed at
// runtime; we break dependencies between subsequent accesses with a tile by
// maintining multiple pointers (we have enough registers), a tiny
// optimization.
const int4* B_ptr[b_sh_wr_iters];
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++)
B_ptr[i] = B + b_gl_rd_delta_i * i + b_gl_rd;
bool m_sh_wr_pred = threadIdx.x < m_sh_wr_delta;
const int4* meta_ptr[m_sh_iters];
#pragma unroll
for (int i = 0; i < m_sh_iters; i++)
meta_ptr[i] = meta + m_gl_rd_delta_i * i + m_gl_rd;
extern __shared__ int4 sh[];
// Shared memory storage for global fetch pipelines.
int4* sh_a = sh;
int4* sh_b = sh_a + (stages * a_sh_stage);
int4* sh_s = sh_b + (stages * b_sh_stage);
int4* sh_m = sh_s + (stages * s_sh_stage);
// Register storage for double buffer of shared memory reads.
FragA frag_a[2][thread_m_blocks][2];
I4 frag_b_quant[2][b_thread_vecs];
FragM frag_m[2][2];
FragC frag_c[thread_m_blocks][4][2];
FragS frag_s[2][4];
// Zero accumulators.
auto zero_accums = [&]() {
#pragma unroll
for (int i = 0; i < thread_m_blocks * 4 * 2 * 4; i++)
reinterpret_cast<float*>(frag_c)[i] = 0;
};
// Asynchronously fetch the next A, B and s tile from global to the next
// shared memory pipeline location.
auto fetch_to_shared = [&](int pipe, int a_off, bool pred = true) {
if (pred) {
int4* sh_a_stage = sh_a + a_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < a_sh_wr_iters; i++) {
cp_async4_pred(
&sh_a_stage[a_sh_wr_trans[i]],
&A[a_gl_rd_delta_i * i + a_gl_rd + a_gl_rd_delta_o * a_off],
a_sh_wr_pred[i]);
}
int4* sh_b_stage = sh_b + b_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) {
#pragma unroll
for (int j = 0; j < b_thread_vecs; j++) {
cp_async4(&sh_b_stage[b_sh_wr_delta * i + b_sh_wr + j], B_ptr[i] + j);
}
B_ptr[i] += b_gl_rd_delta_o;
}
int4* sh_meta_stage = sh_m + m_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < m_sh_iters; i++) {
if (m_sh_wr_pred)
cp_async4(&sh_meta_stage[m_sh_wr_delta * i + m_sh_wr], meta_ptr[i]);
meta_ptr[i] += m_gl_rd_delta_o;
}
// Only fetch scales if this tile starts a new group
if (group_blocks != -1 && pipe % (group_blocks / thread_k_blocks) == 0) {
int4* sh_s_stage = sh_s + s_sh_stage * pipe;
if (s_sh_wr_pred) cp_async4(&sh_s_stage[s_sh_wr], &s[s_gl_rd]);
s_gl_rd += s_gl_rd_delta;
}
}
// Insert a fence even when we are winding down the pipeline to ensure that
// waiting is also correct at this point.
cp_async_fence();
};
// Wait until the next thread tile has been loaded to shared memory.
auto wait_for_stage = [&]() {
// We only have `stages - 2` active fetches since we are double buffering
// and can only issue the next fetch when it is guaranteed that the previous
// shared memory load is fully complete (as it may otherwise be
// overwritten).
cp_async_wait<stages - 2>();
__syncthreads();
};
// Load the next sub-tile from the current location in the shared memory pipe
// into the current register buffer.
auto fetch_to_registers = [&](int k, int pipe) {
// It may seem inefficient that we reload the groups for every sub-tile;
// however, this does not seem to be a significant bottleneck, while some
// theoretically better attempts have lead to bad instruction ordering by
// the compiler and correspondingly a noticeable drop in performance.
if (group_blocks != -1) {
int4* sh_s_stage =
sh_s + s_sh_stage * ((group_blocks / thread_k_blocks) *
(pipe / (group_blocks / thread_k_blocks)));
reinterpret_cast<int4*>(&frag_s[k % 2])[0] = sh_s_stage[s_sh_rd];
}
int4* sh_a_stage = sh_a + a_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
ldsm4(frag_a[k % 2][i][0],
&sh_a_stage[a_sh_rd_trans[0][k % b_sh_wr_iters][i]]);
ldsm4(frag_a[k % 2][i][1],
&sh_a_stage[a_sh_rd_trans[1][k % b_sh_wr_iters][i]]);
}
int4* sh_b_stage = sh_b + b_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < b_thread_vecs; i++) {
frag_b_quant[k % 2][i] = *reinterpret_cast<I4*>(
&sh_b_stage[b_sh_rd_delta * (k % b_sh_wr_iters) + b_sh_rd + i]);
}
// Load meta with ldsm4
int4* sh_m_stage = sh_m + m_sh_stage * pipe;
ldsm4_m(frag_m[k % 2][0],
&sh_m_stage[m_sh_rd_delta * (k % m_sh_iters) + m_sh_rd]);
};
// Execute the actual tensor core matmul of a sub-tile.
auto matmul = [&](int k) {
// We have the m dimension as the inner loop in order to encourage overlapping
// dequantization and matmul operations.
#pragma unroll
for (int j = 0; j < 4; j++) {
FragB frag_b0;
FragB frag_b1;
if constexpr (num_bits == 4) {
int b_quant = frag_b_quant[k % 2][0][j];
int b_quant_shift = b_quant >> 8;
frag_b0 = dequant_4bit(b_quant);
frag_b1 = dequant_4bit(b_quant_shift);
} else {
int* frag_b_quant_ptr = reinterpret_cast<int*>(frag_b_quant[k % 2]);
int b_quant_0 = frag_b_quant_ptr[j * 2 + 0];
int b_quant_1 = frag_b_quant_ptr[j * 2 + 1];
frag_b0 = dequant_8bit(b_quant_0);
frag_b1 = dequant_8bit(b_quant_1);
}
// If there are no groups, we can just scale the final output once and can
// avoid doing so for each weight.
if constexpr (group_blocks != -1) {
scale(frag_b0, frag_s[k % 2][j], 0);
}
if constexpr (group_blocks != -1) {
scale(frag_b1, frag_s[k % 2][j], 1);
}
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
mma_sp(frag_b0, frag_b1, frag_a[k % 2][i][0], frag_c[i][j][0],
frag_m[k % 2][j / 2], j % 2);
}
}
};
// Since we slice across the k dimension of a tile in order to increase the
// number of warps while keeping the n dimension of a tile reasonable, we have
// multiple warps that accumulate their partial sums of the same output
// location; which we have to reduce over in the end. We do in shared memory.
auto thread_block_reduce = [&]() {
constexpr int red_off = threads / b_sh_stride_threads / 2;
if (red_off >= 1) {
int red_idx = threadIdx.x / b_sh_stride_threads;
constexpr int red_sh_stride = b_sh_stride_threads * 4 * 2;
constexpr int red_sh_delta = b_sh_stride_threads;
int red_sh_rd = red_sh_stride * (threadIdx.x / b_sh_stride_threads) +
(threadIdx.x % b_sh_stride_threads);
// Parallel logarithmic shared memory reduction. We make sure to avoid any
// unnecessary read or write iterations, e.g., for two warps we write only
// once by warp 1 and read only once by warp 0.
#pragma unroll
for (int m_block = 0; m_block < thread_m_blocks; m_block++) {
#pragma unroll
for (int i = red_off; i > 0; i /= 2) {
if (i <= red_idx && red_idx < 2 * i) {
#pragma unroll
for (int j = 0; j < 4 * 2; j++) {
int red_sh_wr =
red_sh_delta * j + (red_sh_rd - red_sh_stride * i);
if (i < red_off) {
float* c_rd =
reinterpret_cast<float*>(&sh[red_sh_delta * j + red_sh_rd]);
float* c_wr = reinterpret_cast<float*>(&sh[red_sh_wr]);
#pragma unroll
for (int k = 0; k < 4; k++)
reinterpret_cast<FragC*>(frag_c)[4 * 2 * m_block + j][k] +=
c_rd[k] + c_wr[k];
}
sh[red_sh_wr] =
reinterpret_cast<int4*>(&frag_c)[4 * 2 * m_block + j];
}
}
__syncthreads();
}
if (red_idx == 0) {
#pragma unroll
for (int i = 0; i < 4 * 2; i++) {
float* c_rd =
reinterpret_cast<float*>(&sh[red_sh_delta * i + red_sh_rd]);
#pragma unroll
for (int j = 0; j < 4; j++)
reinterpret_cast<FragC*>(frag_c)[4 * 2 * m_block + i][j] +=
c_rd[j];
}
}
__syncthreads();
}
}
};
// Since multiple threadblocks may process parts of the same column slice, we
// finally have to globally reduce over the results. As the striped
// partitioning minimizes the number of such reductions and our outputs are
// usually rather small, we perform this reduction serially in L2 cache.
auto global_reduce = [&](bool first = false, bool last = false) {
// We are very careful here to reduce directly in the output buffer to
// maximize L2 cache utilization in this step. To do this, we write out
// results in FP16 (but still reduce with FP32 compute).
constexpr int active_threads = 32 * thread_n_blocks / 4;
if (threadIdx.x < active_threads) {
int c_gl_stride = prob_n / 8;
int c_gl_wr_delta_o = 2 * 4 * c_gl_stride;
int c_gl_wr_delta_i =
c_gl_stride; // 8 threads (e.g., 0,4,8,12,16,20,24,28)
int c_gl_wr = 2 * c_gl_stride * (threadIdx.x % 4) +
8 * (threadIdx.x / 32) + (threadIdx.x % 32) / 4;
c_gl_wr += (2 * thread_n_blocks) * slice_col;
constexpr int c_sh_wr_delta = active_threads;
int c_sh_wr = threadIdx.x;
int col = 2 * ((threadIdx.x % 32) % 4);
if (!first) {
// Interestingly, doing direct global accesses here really seems to mess up
// the compiler and lead to slowdowns, hence we also use async-copies even
// though these fetches are not actually asynchronous.
#pragma unroll
for (int i = 0; i < thread_m_blocks * 4; i++) {
cp_async4_pred(&sh[c_sh_wr + c_sh_wr_delta * i],
&C[c_gl_wr + c_gl_wr_delta_o * (i / 2) +
c_gl_wr_delta_i * (i % 2)],
i < (thread_m_blocks - 1) * 4 ||
8 * (i / 2) + col + (i % 2) < prob_m);
}
cp_async_fence();
cp_async_wait<0>();
}
#pragma unroll
for (int i = 0; i < thread_m_blocks * 4; i++) {
if (i < (thread_m_blocks - 1) * 4 ||
8 * (i / 2) + col + (i % 2) < prob_m) {
if (!first) {
int4 c_red = sh[c_sh_wr + i * c_sh_wr_delta];
#pragma unroll
for (int j2 = 0; j2 < 2; j2++) {
#pragma unroll
for (int j1 = 0; j1 < 4; j1++) {
reinterpret_cast<float*>(
&frag_c)[4 * 2 * 4 * (i / 4) + 8 * j1 + 2 * j2 +
4 * ((i % 4) / 2) + i % 2] +=
__half2float(
reinterpret_cast<__half*>(&c_red)[(j2 * 4 + j1)]);
}
}
}
if (!last) {
int4 c;
#pragma unroll
for (int j2 = 0; j2 < 2; j2++) {
#pragma unroll
for (int j1 = 0; j1 < 4; j1++) {
reinterpret_cast<__half*>(&c)[(j2 * 4 + j1)] =
__float2half(reinterpret_cast<float*>(
&frag_c)[4 * 2 * 4 * (i / 4) + 8 * j1 + 2 * j2 +
4 * ((i % 4) / 2) + i % 2]);
}
}
C[c_gl_wr + c_gl_wr_delta_o * (i / 2) + c_gl_wr_delta_i * (i % 2)] =
c;
}
}
}
}
};
// Write out the reduce final result in the correct layout. We only actually
// reshuffle matrix fragments in this step, the reduction above is performed
// in fragment layout.
auto write_result = [&]() {
int c_gl_stride = prob_n / 8;
constexpr int c_sh_stride = 2 * thread_n_blocks; // RLC:
constexpr int c_sh_stride_2 = 2 * c_sh_stride + 2; // RLC:
constexpr int c_sh_stride_3 = 2 * (2 * thread_n_blocks) + 2; // RLC:
int c_gl_wr_delta = c_gl_stride * (threads / (2 * thread_n_blocks));
int c_gl_wr = c_gl_stride * (threadIdx.x / (2 * thread_n_blocks)) +
(threadIdx.x % (2 * thread_n_blocks));
c_gl_wr += (2 * thread_n_blocks) * slice_col;
int c_sh_wr = c_sh_stride_2 * ((threadIdx.x % 32) % 4) +
((threadIdx.x % 32) / 4); // RLC:
c_sh_wr += 8 * (threadIdx.x / 32); // 128/4(half4)
constexpr int c_sh_rd_delta =
c_sh_stride_3 * (threads / (2 * 2 * thread_n_blocks)); // RLC:
int c_sh_rd = c_sh_stride_3 * (threadIdx.x / (2 * 2 * thread_n_blocks)) +
(threadIdx.x % (2 * 2 * thread_n_blocks));
int c_gl_wr_end = c_gl_stride * prob_m;
auto write = [&](int idx, float c0, float c1, float c2, float c3, FragS& s0,
float c4, float c5, float c6, float c7, FragS& s1) {
uint2 res[2];
res[0] = to_half4(c0, c1, c2, c3);
res[1] = to_half4(c4, c5, c6, c7);
half2* tmp = (half2*)&res;
// for per-column quantization we finally apply the scale here
if constexpr (group_blocks == -1 && num_bits == 4) {
tmp[0] = __hmul2(tmp[0], s0[0]);
tmp[1] = __hmul2(tmp[1], s0[1]);
tmp[2] = __hmul2(tmp[2], s1[0]);
tmp[3] = __hmul2(tmp[3], s1[1]);
}
((int4*)sh)[idx] = *((int4*)&res[0]);
};
// RLC: only warp 0 and 1 baseline example
if (threadIdx.x / 32 < thread_n_blocks / 4) {
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
int wr = c_sh_wr;
write(wr, frag_c[i][0][0][0], frag_c[i][1][0][0], frag_c[i][2][0][0],
frag_c[i][3][0][0], frag_s[0][0], frag_c[i][0][0][2],
frag_c[i][1][0][2], frag_c[i][2][0][2], frag_c[i][3][0][2],
frag_s[0][2]);
write(wr + c_sh_stride, frag_c[i][0][0][1], frag_c[i][1][0][1],
frag_c[i][2][0][1], frag_c[i][3][0][1], frag_s[0][0],
frag_c[i][0][0][3], frag_c[i][1][0][3], frag_c[i][2][0][3],
frag_c[i][3][0][3], frag_s[0][2]);
write(wr + 4 * c_sh_stride_2, frag_c[i][0][1][0], frag_c[i][1][1][0],
frag_c[i][2][1][0], frag_c[i][3][1][0], frag_s[0][0],
frag_c[i][0][1][2], frag_c[i][1][1][2], frag_c[i][2][1][2],
frag_c[i][3][1][2], frag_s[0][2]);
write(wr + 4 * c_sh_stride_2 + c_sh_stride, frag_c[i][0][1][1],
frag_c[i][1][1][1], frag_c[i][2][1][1], frag_c[i][3][1][1],
frag_s[0][0], frag_c[i][0][1][3], frag_c[i][1][1][3],
frag_c[i][2][1][3], frag_c[i][3][1][3], frag_s[0][2]);
c_sh_wr += 8 * c_sh_stride_2;
}
}
__syncthreads();
#pragma unroll
for (int i = 0;
i < ceildiv(16 * thread_m_blocks, threads / (2 * thread_n_blocks));
i++) {
if (c_gl_wr < c_gl_wr_end) {
C[c_gl_wr] = sh[c_sh_rd];
c_gl_wr += c_gl_wr_delta;
c_sh_rd += c_sh_rd_delta;
}
}
};
// Start global fetch and register load pipelines.
auto start_pipes = [&]() {
#pragma unroll
for (int i = 0; i < stages - 1; i++) fetch_to_shared(i, i, i < slice_iters);
zero_accums();
wait_for_stage();
fetch_to_registers(0, 0);
a_gl_rd += a_gl_rd_delta_o * (stages - 1);
};
start_pipes();
// Main loop.
while (slice_iters) {
// We unroll over both the global fetch and the register load pipeline to
// ensure all shared memory accesses are static. Note that both pipelines have
// even length meaning that the next iteration will always start at index 0.
#pragma unroll
for (int pipe = 0; pipe < stages;) {
fetch_to_shared((pipe + stages - 1) % stages, pipe,
slice_iters >= stages);
matmul(pipe);
wait_for_stage();
fetch_to_registers(pipe + 1, (pipe + 1) % stages);
pipe++;
slice_iters--;
if (slice_iters == 0) break;
}
a_gl_rd += a_gl_rd_delta_o * stages;
// Process results and, if necessary, proceed to the next column slice.
// While this pattern may not be the most readable, other ways of writing
// the loop seemed to noticeably worse performance after compilation.
if (slice_iters == 0) {
cp_async_wait<0>();
bool last = slice_idx == slice_count - 1;
// For per-column scales, we only fetch them here in the final step before
// write-out
if constexpr (group_blocks == -1) {
if constexpr (num_bits == 8) {
if (s_sh_wr_pred) cp_async4(&sh_s[s_sh_wr], &s[s_gl_rd]);
cp_async_fence();
} else {
if (last) {
if (s_sh_wr_pred) cp_async4(&sh_s[s_sh_wr], &s[s_gl_rd]);
cp_async_fence();
}
}
}
thread_block_reduce();
if constexpr (group_blocks == -1) {
if constexpr (num_bits == 8) {
cp_async_wait<0>();
__syncthreads();
if (threadIdx.x / 32 < thread_n_blocks / 4) {
*(float4*)(frag_s) = *(float4*)(&sh_s[s_sh_rd]);
}
} else {
if (last) {
cp_async_wait<0>();
__syncthreads();
if (threadIdx.x / 32 < thread_n_blocks / 4) {
*(float4*)(frag_s) = *(float4*)(&sh_s[s_sh_rd]);
}
}
}
}
// For 8-bit channelwise, we apply the scale before the global reduction
// that converts the fp32 results to fp16 (so that we avoid possible
// overflow in fp16)
if constexpr (group_blocks == -1 && num_bits == 8) {
if (threadIdx.x / 32 < thread_n_blocks / 4) {
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
scale_floats(&frag_c[i][0][0][0], &frag_c[i][1][0][0],
&frag_c[i][2][0][0], &frag_c[i][3][0][0], frag_s[0][0],
&frag_c[i][0][0][2], &frag_c[i][1][0][2],
&frag_c[i][2][0][2], &frag_c[i][3][0][2],
frag_s[0][2]);
scale_floats(&frag_c[i][0][0][1], &frag_c[i][1][0][1],
&frag_c[i][2][0][1], &frag_c[i][3][0][1], frag_s[0][0],
&frag_c[i][0][0][3], &frag_c[i][1][0][3],
&frag_c[i][2][0][3], &frag_c[i][3][0][3],
frag_s[0][2]);
scale_floats(&frag_c[i][0][1][0], &frag_c[i][1][1][0],
&frag_c[i][2][1][0], &frag_c[i][3][1][0], frag_s[0][0],
&frag_c[i][0][1][2], &frag_c[i][1][1][2],
&frag_c[i][2][1][2], &frag_c[i][3][1][2],
frag_s[0][2]);
scale_floats(&frag_c[i][0][1][1], &frag_c[i][1][1][1],
&frag_c[i][2][1][1], &frag_c[i][3][1][1], frag_s[0][0],
&frag_c[i][0][1][3], &frag_c[i][1][1][3],
&frag_c[i][2][1][3], &frag_c[i][3][1][3],
frag_s[0][2]);
}
}
}
if (slice_count > 1) { // only globally reduce if there is more than one
// block in a slice
barrier_acquire(&locks[slice_col], slice_idx);
global_reduce(slice_idx == 0, last);
barrier_release(&locks[slice_col], last);
}
if (last) // only the last block in a slice actually writes the result
write_result();
slice_row = 0;
slice_col_par++;
slice_col++;
init_slice();
if (slice_iters) {
a_gl_rd = a_gl_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++)
B_ptr[i] += b_sh_stride - b_gl_rd_delta_o * k_tiles;
#pragma unroll
for (int i = 0; i < m_sh_iters; i++)
meta_ptr[i] += (m_sh_stride)-m_gl_rd_delta_o * k_tiles;
if (slice_col == 0) {
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) B_ptr[i] -= b_gl_stride;
#pragma unroll
for (int i = 0; i < m_sh_iters; i++) meta_ptr[i] -= m_gl_stride;
}
s_gl_rd = s_sh_stride * slice_col + threadIdx.x;
start_pipes();
}
}
}
}
#endif
#define CALL_IF_2_4(NUM_BITS, THREAD_M_BLOCKS, THREAD_N_BLOCKS, \
THREAD_K_BLOCKS, GROUP_BLOCKS) \
else if (num_bits == NUM_BITS && thread_m_blocks == THREAD_M_BLOCKS && \
thread_n_blocks == THREAD_N_BLOCKS && \
thread_k_blocks == THREAD_K_BLOCKS && \
group_blocks == GROUP_BLOCKS) { \
cudaFuncSetAttribute( \
Marlin_24<NUM_BITS, THREADS, THREAD_N_BLOCKS, THREAD_M_BLOCKS, \
THREAD_K_BLOCKS, STAGES, GROUP_BLOCKS>, \
cudaFuncAttributeMaxDynamicSharedMemorySize, max_shared_mem); \
Marlin_24<NUM_BITS, THREADS, THREAD_N_BLOCKS, THREAD_M_BLOCKS, \
THREAD_K_BLOCKS, STAGES, GROUP_BLOCKS> \
<<<blocks, THREADS, max_shared_mem, stream>>>(A_ptr, B_ptr, meta_ptr, \
C_ptr, s_ptr, prob_n, \
prob_m, prob_k, locks); \
}
void marlin_cuda_2_4(const void* A, const void* B, const void* meta, void* C,
void* s, int prob_m, int prob_n, int prob_k,
void* workspace, int num_bits, int groupsize = -1,
int dev = 0, cudaStream_t stream = 0, int thread_k = -1,
int thread_m = -1, int sms = -1, int max_par = 16) {
int tot_n = prob_n;
int tot_n_blocks = ceildiv(tot_n, 16);
int pad = 16 * tot_n_blocks - tot_n;
if (sms == -1) {
cudaDeviceGetAttribute(&sms, cudaDevAttrMultiProcessorCount, dev);
}
TORCH_CHECK(sms > 0);
int max_shared_mem = 0;
cudaDeviceGetAttribute(&max_shared_mem,
cudaDevAttrMaxSharedMemoryPerBlockOptin, dev);
TORCH_CHECK(max_shared_mem > 0);
if (thread_k == -1 || thread_m == -1) {
if (prob_n <= 16) {
// For small batchizes, better partitioningif is slightly more important
// than better compute utilization
thread_k = 128;
thread_m = 128;
} else if (prob_n <= 256) {
thread_k = 64;
thread_m = 256;
} else {
thread_k = 32;
thread_m = 512;
}
}
int thread_k_blocks = thread_k / 32; // 2:4 version with m16n8k32 instruction
int thread_m_blocks = thread_m / 16;
int group_blocks = (groupsize == -1) ? -1 : groupsize / 16;
int blocks = sms;
TORCH_CHECK(prob_m % thread_m == 0, "prob_m = ", prob_m,
" is not divisible by thread_m = ", thread_m);
TORCH_CHECK(prob_k % thread_k == 0, "prob_k = ", prob_k,
" is not divisible by thread_k = ", thread_k);
if (group_blocks != -1) {
TORCH_CHECK((prob_k / 2) % group_blocks == 0, "prob_k/2 = ", prob_k / 2,
" is not divisible by group_blocks = ", group_blocks);
}
TORCH_CHECK(prob_m > 0 && prob_n > 0 && prob_k > 0, "Invalid MNK = [", prob_m,
", ", prob_n, ", ", prob_k, "]");
const int4* A_ptr = (const int4*)A;
const int4* B_ptr = (const int4*)B;
const int4* meta_ptr = (const int4*)meta;
int4* C_ptr = (int4*)C;
const int4* s_ptr = (const int4*)s;
constexpr int max_m_blocks = 4;
int* locks = (int*)workspace;
for (int i = 0; i < tot_n_blocks; i += max_m_blocks) {
int thread_n_blocks = tot_n_blocks - i;
prob_n = tot_n - 16 * i;
int par = 1;
if (thread_n_blocks > max_m_blocks) {
// Note that parallel > 1 currently only works for inputs without any
// padding
par = (16 * thread_n_blocks - pad) / (max_m_blocks * 16);
if (par > max_par) par = max_par;
prob_n = (max_m_blocks * 16) * par;
i += max_m_blocks * (par - 1);
thread_n_blocks = max_m_blocks;
}
// For compilation speed, we only define the kernel configurations that have
// seemed useful (in terms of performance) in our testing, however many more
// are, in principle, possible.
// the false is start of the CALL_IF macros
if (false) {
} // BMxBNxBK, group
// 4-bit
CALL_IF_2_4(4, 8, 1, 4, -1) // e.g., 16x128x128
CALL_IF_2_4(4, 8, 1, 4, 4) // e.g., 16x128x128, 64
CALL_IF_2_4(4, 16, 1, 2, -1) // e.g., 16x256x64
CALL_IF_2_4(4, 16, 1, 2, 4) // e.g., 16x256x64, 64
CALL_IF_2_4(4, 16, 2, 2, -1) // e.g.. 32x256x64
CALL_IF_2_4(4, 16, 2, 2, 4)
CALL_IF_2_4(4, 16, 3, 2, -1)
CALL_IF_2_4(4, 16, 3, 2, 4)
CALL_IF_2_4(4, 16, 4, 2, -1)
CALL_IF_2_4(4, 16, 4, 2, 4)
CALL_IF_2_4(4, 32, 1, 1, -1) // e.g., 16x256x64
CALL_IF_2_4(4, 32, 1, 1, 4) // e.g., 16x256x64, 64
CALL_IF_2_4(4, 32, 2, 1, -1) // e.g.. 32x256x64
CALL_IF_2_4(4, 32, 2, 1, 4)
CALL_IF_2_4(4, 32, 3, 1, -1)
CALL_IF_2_4(4, 32, 3, 1, 4)
CALL_IF_2_4(4, 32, 4, 1, -1)
CALL_IF_2_4(4, 32, 4, 1, 4)
// 8-bit
CALL_IF_2_4(8, 8, 1, 4, -1) // e.g., 16x128x128
CALL_IF_2_4(8, 8, 1, 4, 4) // e.g., 16x128x128, 64
CALL_IF_2_4(8, 16, 1, 2, -1) // e.g., 16x256x64
CALL_IF_2_4(8, 16, 1, 2, 4) // e.g., 16x256x64, 64
CALL_IF_2_4(8, 16, 2, 2, -1) // e.g.. 32x256x64
CALL_IF_2_4(8, 16, 2, 2, 4)
CALL_IF_2_4(8, 16, 3, 2, -1)
CALL_IF_2_4(8, 16, 3, 2, 4)
CALL_IF_2_4(8, 16, 4, 2, -1)
CALL_IF_2_4(8, 16, 4, 2, 4)
CALL_IF_2_4(8, 32, 1, 1, -1) // e.g., 16x256x64
CALL_IF_2_4(8, 32, 1, 1, 4) // e.g., 16x256x64, 64
CALL_IF_2_4(8, 32, 2, 1, -1) // e.g.. 32x256x64
CALL_IF_2_4(8, 32, 2, 1, 4)
CALL_IF_2_4(8, 32, 3, 1, -1)
CALL_IF_2_4(8, 32, 3, 1, 4)
CALL_IF_2_4(8, 32, 4, 1, -1)
CALL_IF_2_4(8, 32, 4, 1, 4)
else {
throw std::runtime_error("Unsupported shapes: MKN = [" + str(prob_m) +
", " + str(prob_k) + ", " + str(prob_n) + "]" +
", groupsize = " + str(groupsize) +
", thread_m_blocks = " + str(thread_m_blocks) +
", thread_n_blocks = " + str(thread_n_blocks) +
", thread_k_blocks = " + str(thread_k_blocks));
}
A_ptr += 16 * thread_n_blocks * (prob_k / 8) * par;
C_ptr += 16 * thread_n_blocks * (prob_m / 8) * par;
}
}
} // namespace marlin_24
torch::Tensor gptq_marlin_24_gemm(torch::Tensor& a, torch::Tensor& b_q_weight,
torch::Tensor& b_meta,
torch::Tensor& b_scales,
torch::Tensor& workspace, int64_t num_bits,
int64_t size_m, int64_t size_n,
int64_t size_k) {
// Verify num_bits
TORCH_CHECK(num_bits == 4 || num_bits == 8,
"num_bits must be 4 or 8. Got = ", num_bits);
int pack_factor = 32 / num_bits;
// Verify M
TORCH_CHECK(size_m == a.size(0),
"Shape mismatch: a.size(0) = " + str(a.size(0)) +
", size_m = " + str(size_m));
// Verify K
TORCH_CHECK(size_k == a.size(1),
"Shape mismatch: a.size(1) = " + str(a.size(1)) +
", size_k = " + str(size_k));
TORCH_CHECK(size_k % marlin_24::tile_size == 0,
"size_k = " + str(size_k) + " is not divisible by tile_size = " +
str(marlin_24::tile_size));
TORCH_CHECK((size_k / marlin_24::tile_size / 2) == b_q_weight.size(0),
"Shape mismatch: b_q_weight.size(0) = " +
str(b_q_weight.size(0)) + ", size_k = " + str(size_k) +
", tile_size = " + str(marlin_24::tile_size));
// Verify N
TORCH_CHECK(b_scales.size(1) == size_n,
"b_scales.size(1) = " + str(b_scales.size(1)) +
", size_n = " + str(size_n));
TORCH_CHECK(
b_q_weight.size(1) % marlin_24::tile_size == 0,
"b_q_weight.size(1) = " + str(b_q_weight.size(1)) +
" is not divisible by tile_size = " + str(marlin_24::tile_size));
int actual_size_n = (b_q_weight.size(1) / marlin_24::tile_size) * pack_factor;
TORCH_CHECK(
size_n == actual_size_n,
"size_n = " + str(size_n) + ", actual_size_n = " + str(actual_size_n));
// Verify meta
TORCH_CHECK(b_meta.size(0) == size_k / 8 / 2 / 2,
"b_meta.size(0) = ", b_meta.size(0),
" is not size_k / 8 / 2 / 2 = ", size_k / 8 / 2 / 2);
TORCH_CHECK(b_meta.size(1) == size_n * 2, "b_meta.size(1) = ", b_meta.size(1),
" is not size_n * 2 = ", size_n * 2);
// Verify A device and strides
TORCH_CHECK(a.device().is_cuda(), "A is not on GPU");
TORCH_CHECK(a.is_contiguous(), "A is not contiguous");
// Verify B device and strides
TORCH_CHECK(b_q_weight.device().is_cuda(), "b_q_weight is not on GPU");
TORCH_CHECK(b_q_weight.is_contiguous(), "b_q_weight is not contiguous");
// Verify b_meta device and strides
TORCH_CHECK(b_meta.device().is_cuda(), "b_meta is not on GPU");
TORCH_CHECK(b_meta.is_contiguous(), "b_meta is not contiguous");
// Verify scales device and strides
TORCH_CHECK(b_scales.device().is_cuda(), "b_scales is not on GPU");
TORCH_CHECK(b_scales.is_contiguous(), "b_scales is not contiguous");
// Alloc C matrix
const at::cuda::OptionalCUDAGuard device_guard(device_of(a));
auto options = torch::TensorOptions().dtype(a.dtype()).device(a.device());
torch::Tensor c = torch::empty({size_m, size_n}, options);
int thread_k = -1;
int thread_m = -1;
int sms = -1;
int max_par = marlin_24::max_par;
int groupsize = -1;
if (b_scales.size(0) > 1) {
TORCH_CHECK(size_k % b_scales.size(0) == 0,
"size_k = " + str(size_k) +
", is not divisible by b_scales.size(0) = " +
str(b_scales.size(0)));
groupsize = size_k / b_scales.size(0);
groupsize /= 2; // Because of 24
}
// Verify groupsize
TORCH_CHECK(groupsize == -1 || groupsize == 64,
"Unexpected groupsize = " + str(groupsize));
// Verify workspace size
TORCH_CHECK(size_n % marlin_24::min_thread_n == 0,
"size_n = " + str(size_n) +
", is not divisible by min_thread_n = " +
str(marlin_24::min_thread_n));
int min_workspace_size =
(size_n / marlin_24::min_thread_n) * marlin_24::max_par;
TORCH_CHECK(workspace.numel() >= min_workspace_size,
"workspace.numel = " + str(workspace.numel()) +
" is below min_workspace_size = " + str(min_workspace_size));
int dev = a.get_device();
marlin_24::marlin_cuda_2_4(
a.data_ptr(), b_q_weight.data_ptr(), b_meta.data_ptr(), c.data_ptr(),
b_scales.data_ptr(), size_n, size_m, size_k, workspace.data_ptr(),
num_bits, groupsize, dev, at::cuda::getCurrentCUDAStream(dev), thread_k,
thread_m, sms, max_par);
return c;
}
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