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2023-12-15 19:04:22 +08:00
/*
Adapted from https://github.com/turboderp/exllamav2 and https://github.com/qwopqwop200/GPTQ-for-LLaMa
*/
#include <cstdint>
#include <cstdio>
#include <torch/extension.h>
#include <c10/cuda/CUDAGuard.h>
#include <ATen/cuda/CUDAContext.h>
#include <cuda_runtime.h>
#include <cuda_fp16.h>
#include "compat.cuh"
#include "matrix_view.cuh"
#include "qdq_4.cuh"
namespace vllm {
namespace gptq {
#define BLOCK_KN_SIZE 128
#define BLOCK_M_SIZE_MAX 8
#define MAX_GROUPS_IN_BLOCK (BLOCK_KN_SIZE / 32)
#define MAX_Q_GEMM_ROWS 50
#define MAX_ALT_GEMM_ROWS 8
#define THREADS_X 32
#define THREADS_Y 32
#define DIVIDE(x, size) (((x) + (size) - 1) / (size))
#if defined(USE_ROCM)
__host__ __forceinline__ hipblasStatus_t __compat_hipblasHgemm(hipblasHandle_t handle,
hipblasOperation_t transA,
hipblasOperation_t transB,
int m,
int n,
int k,
const half* alpha,
const half* AP,
int lda,
const half* BP,
int ldb,
const half* beta,
half* CP,
int ldc) {
return hipblasHgemm(handle, transA, transB, m, n, k,
reinterpret_cast<const hipblasHalf *>(alpha),
reinterpret_cast<const hipblasHalf *>(AP), lda,
reinterpret_cast<const hipblasHalf *>(BP), ldb,
reinterpret_cast<const hipblasHalf *>(beta),
reinterpret_cast<hipblasHalf *>(CP), ldc);
}
#define hipblasHgemm __compat_hipblasHgemm
// Previous version of PyTorch were converting to rocBLAS instead of hipBLAS.
#define rocblas_operation_none HIPBLAS_OP_N
#define rocblas_hgemm __compat_hipblasHgemm
#endif
__forceinline__ __device__ half2 dot22_8(half2(&dq)[4], const half* a_ptr, const half2 g_result)
{
half2 result = {};
const half2* a2_ptr = (const half2*)a_ptr;
#pragma unroll
for (int i = 0; i < 4; i++) result = __hfma2(dq[i], *a2_ptr++, result);
return __hadd2(result, g_result);
}
__forceinline__ __device__ float dot22_8_f(half2(&dq)[4], const half* a_ptr)
{
half2 result = {};
const half2* a2_ptr = (const half2*)a_ptr;
#pragma unroll
for (int i = 0; i < 4; i++) result = __hfma2(dq[i], *a2_ptr++, result);
return __half2float(__low2half(result)) + __half2float(__high2half(result));
}
typedef void (*fp_gemm_half_q_half_gptq_kernel)
(
const half*,
const uint32_t*,
const uint32_t*,
const half*,
half*,
const int,
const int,
const int,
const int,
const int*
);
template <bool first_block, int m_count>
__global__ void gemm_half_q_half_gptq_kernel
(
const half* __restrict__ a,
const uint32_t* __restrict__ b_q_weight,
const uint32_t* __restrict__ b_gptq_qzeros,
const half* __restrict__ b_gptq_scales,
half* __restrict__ c,
const int size_m,
const int size_n,
const int size_k,
const int groups,
const int* __restrict__ b_q_perm
)
{
MatrixView_half a_(a, size_m, size_k);
MatrixView_half_rw c_(c, size_m, size_n);
MatrixView_q4_row b_gptq_qzeros_(b_gptq_qzeros, groups, size_n);
MatrixView_half b_gptq_scales_(b_gptq_scales, groups, size_n);
int t = threadIdx.x;
// Block
int offset_n = blockIdx.x * BLOCK_KN_SIZE * 4;
int offset_m = blockIdx.y * m_count;
int offset_k = blockIdx.z * BLOCK_KN_SIZE;
int end_n = min(offset_n + BLOCK_KN_SIZE * 4, size_n);
int end_m = min(offset_m + m_count, size_m);
int end_k = min(offset_k + BLOCK_KN_SIZE, size_k);
int n = offset_n + t * 4;
// Preload block_a
__shared__ half block_a[m_count][BLOCK_KN_SIZE];
if (offset_k + t < end_k)
{
for (int m = 0; m < m_count; ++m)
{
const half* a_ptr = a_.item_ptr(offset_m + m, 0);
half* block_a_ptr = block_a[m];
half a0;
if (b_q_perm) a0 = a_ptr[b_q_perm[offset_k + t]];
else a0 = a_ptr[offset_k + t];
block_a_ptr[t] = a0;
}
}
// Zero output
if (n >= size_n) return;
if (blockIdx.z == 0)
{
for (int m = 0; m < m_count; m++)
*((uint64_t*)c_.item_ptr(offset_m + m, n)) = 0;
}
__syncthreads();
// Find initial group
int groupsize = size_k / groups;
int group = offset_k / groupsize;
int nextgroup = offset_k + groupsize;
// a, b offset
int qk = offset_k / (32 / 4);
const uint32_t* b_ptr = b_q_weight + qk * size_n + n;
const half* a_ptr = &block_a[0][0];
int a_stride = BLOCK_KN_SIZE;
// Initial group
int zeros[4];
float scales[4];
half2 z1z16[4][2];
half2 y1y16[4][2];
b_gptq_qzeros_.item4(zeros, group, n);
b_gptq_scales_.item4_f(scales, group, n);
dequant_4bit_8_prep_zero(zeros[0] + 1, z1z16[0], y1y16[0]);
dequant_4bit_8_prep_zero(zeros[1] + 1, z1z16[1], y1y16[1]);
dequant_4bit_8_prep_zero(zeros[2] + 1, z1z16[2], y1y16[2]);
dequant_4bit_8_prep_zero(zeros[3] + 1, z1z16[3], y1y16[3]);
// Column result
float block_c[m_count][4] = {};
// Dequantize and multiply
int k = offset_k;
while (k < end_k)
{
if (k == nextgroup)
{
group++;
nextgroup += groupsize;
b_gptq_qzeros_.item4(zeros, group, n);
b_gptq_scales_.item4_f(scales, group, n);
dequant_4bit_8_prep_zero(zeros[0] + 1, z1z16[0], y1y16[0]);
dequant_4bit_8_prep_zero(zeros[1] + 1, z1z16[1], y1y16[1]);
dequant_4bit_8_prep_zero(zeros[2] + 1, z1z16[2], y1y16[2]);
dequant_4bit_8_prep_zero(zeros[3] + 1, z1z16[3], y1y16[3]);
}
#pragma unroll
for (int j = 0; j < 4; j++)
{
const int4* b_ptr4 = (int4*) b_ptr;
int4 load_int4 = *b_ptr4;
half2 dq[4][4];
dequant_4bit_8_gptq(load_int4.x, dq[0], z1z16[0], y1y16[0], size_n, false);
dequant_4bit_8_gptq(load_int4.y, dq[1], z1z16[1], y1y16[1], size_n, false);
dequant_4bit_8_gptq(load_int4.z, dq[2], z1z16[2], y1y16[2], size_n, false);
dequant_4bit_8_gptq(load_int4.w, dq[3], z1z16[3], y1y16[3], size_n, false);
#pragma unroll
for (int m = 0; m < m_count; m++)
{
block_c[m][0] = fma(dot22_8_f(dq[0], a_ptr + m * a_stride), scales[0], block_c[m][0]);
block_c[m][1] = fma(dot22_8_f(dq[1], a_ptr + m * a_stride), scales[1], block_c[m][1]);
block_c[m][2] = fma(dot22_8_f(dq[2], a_ptr + m * a_stride), scales[2], block_c[m][2]);
block_c[m][3] = fma(dot22_8_f(dq[3], a_ptr + m * a_stride), scales[3], block_c[m][3]);
}
b_ptr += size_n;
a_ptr += 8;
}
k += 32;
}
for (int m = 0; m < m_count; m++)
{
half2 *out = (half2*) c_.item_ptr(offset_m + m, n);
half2 result01 = __halves2half2(__float2half_rn(block_c[m][0]), __float2half_rn(block_c[m][1]));
half2 result23 = __halves2half2(__float2half_rn(block_c[m][2]), __float2half_rn(block_c[m][3]));
atomicAdd(out , result01);
atomicAdd(out + 1, result23);
}
}
fp_gemm_half_q_half_gptq_kernel pick_gemm_half_q_half_gptq_kernel(bool first_block, const int m_count)
{
#if BLOCK_M_SIZE_MAX >= 1
if (m_count == 1) return gemm_half_q_half_gptq_kernel<true, 1>;
#endif
#if BLOCK_M_SIZE_MAX >= 2
if (m_count == 2) return gemm_half_q_half_gptq_kernel<true, 2>;
#endif
#if BLOCK_M_SIZE_MAX >= 3
if (m_count == 3) return gemm_half_q_half_gptq_kernel<true, 3>;
#endif
#if BLOCK_M_SIZE_MAX >= 4
if (m_count == 4) return gemm_half_q_half_gptq_kernel<true, 4>;
#endif
#if BLOCK_M_SIZE_MAX >= 5
if (m_count == 5) return gemm_half_q_half_gptq_kernel<true, 5>;
#endif
#if BLOCK_M_SIZE_MAX >= 6
if (m_count == 6) return gemm_half_q_half_gptq_kernel<true, 6>;
#endif
#if BLOCK_M_SIZE_MAX >= 7
if (m_count == 7) return gemm_half_q_half_gptq_kernel<true, 7>;
#endif
#if BLOCK_M_SIZE_MAX >= 8
if (m_count == 8) return gemm_half_q_half_gptq_kernel<true, 8>;
#endif
return NULL;
}
void gemm_half_q_half_cuda_part
(
const half* a,
const uint32_t* b_q_weight,
const uint32_t* b_gptq_qzeros,
const half* b_gptq_scales,
const int* b_q_perm,
half* c,
int size_m,
int size_n,
int size_k,
int m_count,
int groups
)
{
dim3 blockDim, gridDim;
blockDim.x = BLOCK_KN_SIZE;
blockDim.y = 1;
blockDim.z = 1;
gridDim.x = DIVIDE(size_n, BLOCK_KN_SIZE * 4);
gridDim.y = DIVIDE(size_m, m_count);
gridDim.z = DIVIDE(size_k, BLOCK_KN_SIZE);
fp_gemm_half_q_half_gptq_kernel kernel = pick_gemm_half_q_half_gptq_kernel(true, m_count);
kernel<<<gridDim, blockDim>>>
(
a,
b_q_weight,
b_gptq_qzeros,
b_gptq_scales,
c,
size_m,
size_n,
size_k,
groups,
b_q_perm
);
}
__global__ void reconstruct_exllama_kernel
(
const uint32_t* __restrict__ b_q_weight,
const int* __restrict__ b_q_perm,
const uint32_t* __restrict__ b_gptq_qzeros,
const half* __restrict__ b_gptq_scales,
const int size_k,
const int size_n,
const int groups,
half* __restrict__ b
)
{
MatrixView_half_rw b_(b, size_k, size_n);
MatrixView_q4_row b_gptq_qzeros_(b_gptq_qzeros, groups, size_n);
MatrixView_half b_gptq_scales_(b_gptq_scales, groups, size_n);
int offset_k = BLOCK_KN_SIZE * blockIdx.y;
int offset_n = BLOCK_KN_SIZE * blockIdx.x * 4;
int end_k = min(offset_k + BLOCK_KN_SIZE, size_k);
// Preload remapping table
__shared__ int perm[BLOCK_KN_SIZE];
int t = threadIdx.x;
if (b_q_perm)
{
if (offset_k + t < size_k)
perm[t] = b_q_perm[offset_k + t];
}
// Column
int n = offset_n + t * 4;
if (n >= size_n) return;
// Find initial group
int groupsize = size_k / groups;
int group = offset_k / groupsize;
int nextgroup = offset_k + groupsize;
// b offset
int qk = offset_k / (32 / 4);
const uint32_t* b_ptr = b_q_weight + qk * size_n + n;
// Initial zeros/scale
int zeros[4];
half2 scales[4];
half2 z1z16[4][2];
half2 y1y16[4][2];
b_gptq_qzeros_.item4(zeros, group, n);
b_gptq_scales_.item4_h2(scales, group, n);
dequant_4bit_8_prep_zero(zeros[0] + 1, z1z16[0], y1y16[0]);
dequant_4bit_8_prep_zero(zeros[1] + 1, z1z16[1], y1y16[1]);
dequant_4bit_8_prep_zero(zeros[2] + 1, z1z16[2], y1y16[2]);
dequant_4bit_8_prep_zero(zeros[3] + 1, z1z16[3], y1y16[3]);
__syncthreads();
int k = offset_k;
int lk = 0;
while (k < end_k)
{
if (k == nextgroup)
{
group++;
nextgroup += groupsize;
b_gptq_qzeros_.item4(zeros, group, n);
b_gptq_scales_.item4_h2(scales, group, n);
dequant_4bit_8_prep_zero(zeros[0] + 1, z1z16[0], y1y16[0]);
dequant_4bit_8_prep_zero(zeros[1] + 1, z1z16[1], y1y16[1]);
dequant_4bit_8_prep_zero(zeros[2] + 1, z1z16[2], y1y16[2]);
dequant_4bit_8_prep_zero(zeros[3] + 1, z1z16[3], y1y16[3]);
}
for (int p = 0; p < 4; p++)
{
half2 dq[4][4];
const int4* b_ptr4 = (int4*) b_ptr;
int4 load_int4 = *b_ptr4;
dequant_4bit_8_gptq(load_int4.x, dq[0], z1z16[0], y1y16[0], size_n, false);
dequant_4bit_8_gptq(load_int4.y, dq[1], z1z16[1], y1y16[1], size_n, false);
dequant_4bit_8_gptq(load_int4.z, dq[2], z1z16[2], y1y16[2], size_n, false);
dequant_4bit_8_gptq(load_int4.w, dq[3], z1z16[3], y1y16[3], size_n, false);
b_ptr += size_n;
//half* dqh = (half*)dq;
if (b_q_perm)
{
for (int j = 0; j < 4; j++)
{
for (int v = 0; v < 4; v++) dq[v][j] = __hmul2(scales[v], dq[v][j]);
b_.set4(perm[lk++], n, __low2half(dq[0][j]), __low2half(dq[1][j]), __low2half(dq[2][j]), __low2half(dq[3][j]));
b_.set4(perm[lk++], n, __high2half(dq[0][j]), __high2half(dq[1][j]), __high2half(dq[2][j]), __high2half(dq[3][j]));
}
}
else
{
for (int j = 0; j < 4; j++)
{
for (int v = 0; v < 4; v++) dq[v][j] = __hmul2(scales[v], dq[v][j]);
b_.set4(offset_k + lk++, n, __low2half(dq[0][j]), __low2half(dq[1][j]), __low2half(dq[2][j]), __low2half(dq[3][j]));
b_.set4(offset_k + lk++, n, __high2half(dq[0][j]), __high2half(dq[1][j]), __high2half(dq[2][j]), __high2half(dq[3][j]));
}
}
}
k += 32;
}
}
void reconstruct_exllama
(
const uint32_t* b_q_weight,
const uint32_t* b_gptq_qzeros,
const half* b_gptq_scales,
const int* b_q_perm,
half* out,
int height,
int width,
int groups
)
{
dim3 blockDim, gridDim;
blockDim.x = BLOCK_KN_SIZE;
blockDim.y = 1;
gridDim.y = DIVIDE(height, BLOCK_KN_SIZE);
gridDim.x = DIVIDE(width, BLOCK_KN_SIZE);
reconstruct_exllama_kernel<<<gridDim, blockDim>>>
(
b_q_weight,
b_q_perm,
b_gptq_qzeros,
b_gptq_scales,
height,
width,
groups,
out
);
}
__global__ void gemm_half_q_half_alt_kernel(
const half2* __restrict__ vec,
const uint32_t* __restrict__ mat,
half* __restrict__ mul,
const half* __restrict__ scales,
const uint32_t* __restrict__ zeros,
const int* __restrict__ g_idx,
int batch,
int height,
int width
)
{
int zero_width = width / 8;
int vec_height = height * 4;
const int blockwidth2 = BLOCK_KN_SIZE / 2;
int b = blockIdx.y * BLOCK_M_SIZE_MAX;
int b_end = min(BLOCK_M_SIZE_MAX, batch - b);
int h = BLOCK_KN_SIZE * blockIdx.z / 8;
int h_end = min(BLOCK_KN_SIZE / 8, height - h) * 4;
int w = BLOCK_KN_SIZE * blockIdx.x + threadIdx.x;
__shared__ half2 blockvec[BLOCK_M_SIZE_MAX][blockwidth2];
if (threadIdx.x < h_end) {
for (int m = 0; m < b_end; ++m) {
blockvec[m][threadIdx.x] =
vec[(m + b) * vec_height + blockIdx.z * BLOCK_KN_SIZE / 2 +
threadIdx.x];
}
}
__shared__ half2 deq2[256][8];
int val = threadIdx.x / 8;
int off = threadIdx.x % 8;
for (; val < 256; val += BLOCK_KN_SIZE / 8) {
deq2[val][off] = __halves2half2(
__int2half_rn(val & 0xF), __int2half_rn(val >> 4)
);
}
if (blockIdx.z == 0)
{
for (int m = 0; m < b_end; m++)
mul[(b + m) * width + w] = __int2half_rn(0);
}
__syncthreads();
int i = width * h + w;
int g_h = h * 8;
int k = 0;
int z_w = w / 8;
int z_mod = (w % 8) * 4;
half2 res2;
half res[BLOCK_M_SIZE_MAX] = {};
unsigned int tmp;
while (k < h_end) {
tmp = mat[i];
half2 scales_tmp[4];
half2 zeros_tmp[4];
for (int tmp_k = 0; tmp_k < 4; tmp_k++) {
int g = g_idx[g_h + (k + tmp_k) * 2];
int g2 = g_idx[g_h + (k + tmp_k) * 2 + 1];
half scale_f = scales[g * width + w];
half scale_f2 = scales[g2 * width + w];
half2 scale = __halves2half2(scale_f, scale_f2);
half2 zero = __halves2half2(
__hmul(scale_f, __int2half_rn(-((zeros[g * zero_width + z_w] >> z_mod) & 0xF) - 1)),
__hmul(scale_f2, __int2half_rn(-((zeros[g2 * zero_width + z_w] >> z_mod) & 0xF) - 1))
);
scales_tmp[tmp_k] = scale;
zeros_tmp[tmp_k] = zero;
}
for (int m = 0; m < b_end; m++) {
res2 = {};
res2 = __hfma2(__hfma2(deq2[(tmp >> 0) & 0xff][off], scales_tmp[0], zeros_tmp[0]), blockvec[m][k + 0], res2);
res2 = __hfma2(__hfma2(deq2[(tmp >> 8) & 0xff][off], scales_tmp[1], zeros_tmp[1]), blockvec[m][k + 1], res2);
res2 = __hfma2(__hfma2(deq2[(tmp >> 16) & 0xff][off], scales_tmp[2], zeros_tmp[2]), blockvec[m][k + 2], res2);
res2 = __hfma2(__hfma2(deq2[(tmp >> 24) & 0xff][off], scales_tmp[3], zeros_tmp[3]), blockvec[m][k + 3], res2);
res[m] = __hadd(res[m], __hadd(res2.x, res2.y));
}
i += width;
k += 4;
}
for (int m = 0; m < b_end; m++) {
atomicAdd(&mul[(b + m) * width + w], res[m]);
}
}
void gemm_half_q_half_alt
(
const half* a,
const uint32_t* b_q_weight,
const uint32_t* b_gptq_qzeros,
const half* b_gptq_scales,
const int* b_g_idx,
half* c,
int size_m,
int size_n,
int size_k
)
{
dim3 blockDim, gridDim;
blockDim.x = BLOCK_KN_SIZE;
blockDim.y = 1;
blockDim.z = 1;
gridDim.x = DIVIDE(size_n, BLOCK_KN_SIZE);
gridDim.y = DIVIDE(size_m, BLOCK_M_SIZE_MAX);
gridDim.z = DIVIDE(size_k, BLOCK_KN_SIZE);
gemm_half_q_half_alt_kernel<<<gridDim, blockDim>>>
(
(const half2*) a,
b_q_weight,
c,
b_gptq_scales,
b_gptq_qzeros,
b_g_idx,
size_m,
size_k / 8,
size_n
);
}
__global__ void reconstruct_gptq_kernel
(
const uint32_t* __restrict__ w,
const half* __restrict__ w_scales,
const uint32_t* __restrict__ w_zeros,
const int* __restrict__ g_idx,
const int height,
const int width,
const int group,
half* __restrict__ out
)
{
// Start of block
int column = BLOCK_KN_SIZE * blockIdx.x + threadIdx.x;
int row = blockIdx.y * 8;
if (column >= width) return;
// Views
MatrixView_q4_column w_(w, height, width);
MatrixView_half_rw out_(out, height, width);
MatrixView_half w_scales_(w_scales, group, width);
MatrixView_q4_row w_zeros_(w_zeros, group, width);
uint32_t w_read = w_.item_uint32_t(row, column);
half* out_ptr = out_.item_ptr(row, column);
#pragma unroll
for (int s = 0; s < 32; s += 4)
{
int group = g_idx[row + s / 4];
half w_scale = w_scales_.item(group, column);
uint32_t w_zero = w_zeros_.item(group, column) + 1;
half w_item = __hmul(__int2half_rn((int)((w_read >> s) & 0x0f) - w_zero), w_scale);
*out_ptr = w_item; out_ptr += out_.width;
}
}
void reconstruct_gptq
(
const uint32_t* b_q_weight,
const uint32_t* b_gptq_qzeros,
const half* b_gptq_scales,
const int* b_g_idx,
half* out,
int height,
int width,
int groups
)
{
dim3 blockDim, gridDim;
blockDim.x = BLOCK_KN_SIZE;
blockDim.y = 1;
gridDim.y = DIVIDE(height, 8);
gridDim.x = DIVIDE(width, BLOCK_KN_SIZE);
reconstruct_gptq_kernel<<<gridDim, blockDim>>>
(
b_q_weight,
b_gptq_scales,
b_gptq_qzeros,
b_g_idx,
height,
width,
groups,
out
);
}
void gemm_half_q_half_cuda
(
cublasHandle_t cublas_handle,
const half* a,
const uint32_t* b_q_weight,
const uint32_t* b_gptq_qzeros,
const half* b_gptq_scales,
const int* b_g_idx,
half* c,
half* temp_dq,
int size_m,
int size_n,
int size_k,
int groups,
bool use_exllama
)
{
if ((use_exllama && size_m > MAX_Q_GEMM_ROWS) || (!use_exllama && size_m > MAX_ALT_GEMM_ROWS)) {
// Reconstruct FP16 matrix, then cuBLAS
if (use_exllama) {
reconstruct_exllama(b_q_weight, b_gptq_qzeros, b_gptq_scales, b_g_idx, temp_dq,
size_k, size_n, groups);
}
else
{
reconstruct_gptq(b_q_weight, b_gptq_qzeros, b_gptq_scales, b_g_idx,
temp_dq, size_k, size_n, groups);
}
const half alpha = __float2half(1.0f);
const half beta = __float2half(0.0f);
cublasHgemm(cublas_handle,
CUBLAS_OP_N,
CUBLAS_OP_N,
size_n, size_m, size_k,
&alpha, temp_dq, size_n,
a, size_k,
&beta, c, size_n);
}
else if (use_exllama)
{
// Quantized matmul
int max_chunks = size_m / BLOCK_M_SIZE_MAX;
int last_chunk = max_chunks * BLOCK_M_SIZE_MAX;
int last_chunk_size = size_m - last_chunk;
if (max_chunks)
{
gemm_half_q_half_cuda_part(a, b_q_weight, b_gptq_qzeros, b_gptq_scales, b_g_idx,
c, last_chunk, size_n, size_k, BLOCK_M_SIZE_MAX,
groups);
}
if (last_chunk_size)
{
gemm_half_q_half_cuda_part(a + last_chunk * size_k, b_q_weight, b_gptq_qzeros,
b_gptq_scales, b_g_idx, c + last_chunk * size_n,
last_chunk_size, size_n, size_k, last_chunk_size,
groups);
}
}
else
{
gemm_half_q_half_alt(a, b_q_weight, b_gptq_qzeros, b_gptq_scales, b_g_idx,
c, size_m, size_n, size_k);
}
}
__global__ void shuffle_kernel
(
uint32_t* __restrict__ b_q_weight,
const int size_k,
const int size_n
)
{
int n = blockIdx.x * THREADS_X + threadIdx.x;
if (n >= size_n) return;
int k = 0;
uint32_t* b_ptr = b_q_weight + n;
while (k < size_k) { shuffle_4bit_8 (b_ptr, size_n); b_ptr += 1 * size_n; k += 8; }
}
__global__ void make_sequential_kernel
(
const uint32_t* __restrict__ w,
uint32_t* __restrict__ w_new,
const int* __restrict__ q_perm,
const int w_height,
const int w_width
)
{
const uint64_t* w2 = (uint64_t*) w;
uint64_t* w_new2 = (uint64_t*) w_new;
int w2_stride = w_width >> 1;
int w2_column = THREADS_X * blockIdx.x + threadIdx.x;
if (w2_column >= w2_stride) return;
int w_new2_row = blockIdx.y;
int q_perm_idx = w_new2_row << 3;
uint64_t dst = 0;
#pragma unroll
for (int i = 0; i < 8; i++)
{
int source_row = q_perm[q_perm_idx++];
int w2_row = source_row >> 3;
int w2_subrow = source_row & 0x07;
int w2_row_shift = w2_subrow << 2;
int wnew2_row_shift = i << 2;
uint64_t src = w2[w2_row * w2_stride + w2_column];
src >>= w2_row_shift;
src &= 0x0000000f0000000f;
src <<= wnew2_row_shift;
dst |= src;
}
w_new2[w_new2_row * w2_stride + w2_column] = dst;
}
void shuffle_exllama_weight
(
uint32_t* q_weight,
int* q_perm,
int height,
int width
)
{
if (q_perm)
{
uint32_t* new_qweight = NULL;
cudaMalloc(&new_qweight, height / 8 * width * sizeof(uint32_t));
dim3 blockDim, gridDim;
blockDim.x = THREADS_X;
blockDim.y = 1;
gridDim.x = DIVIDE(width, THREADS_X);
gridDim.y = height / 8;
make_sequential_kernel<<<gridDim, blockDim>>>
(
q_weight,
new_qweight,
q_perm,
height / 8,
width
);
// Replace qweights
cudaMemcpyAsync(q_weight, new_qweight, height / 8 * width * sizeof(uint32_t), cudaMemcpyDeviceToDevice);
// Cleanup
cudaDeviceSynchronize();
cudaFree(new_qweight);
}
dim3 blockDim, gridDim;
blockDim.x = THREADS_X;
blockDim.y = 1;
gridDim.x = DIVIDE(width, THREADS_X);
gridDim.y = 1;
shuffle_kernel<<<gridDim, blockDim>>>(q_weight, height, width);
}
} // namespace gptq
} // namespace vllm
torch::Tensor gptq_gemm
(
torch::Tensor a,
torch::Tensor b_q_weight,
torch::Tensor b_gptq_qzeros,
torch::Tensor b_gptq_scales,
torch::Tensor b_g_idx,
bool use_exllama
)
{
const at::cuda::OptionalCUDAGuard device_guard(device_of(a));
auto options = torch::TensorOptions().dtype(a.dtype()).device(a.device());
at::Tensor c = torch::empty({a.size(0), b_q_weight.size(1)}, options);
at::Tensor temp_dq = torch::empty({b_q_weight.size(0) * 8, b_q_weight.size(1)}, options);
vllm::gptq::gemm_half_q_half_cuda
(
at::cuda::getCurrentCUDABlasHandle(),
(const half*) a.data_ptr(),
(const uint32_t*) b_q_weight.data_ptr(),
(const uint32_t*)b_gptq_qzeros.data_ptr(),
(const half*) b_gptq_scales.data_ptr(),
b_g_idx.device().is_meta() ? NULL : (const int*) b_g_idx.data_ptr(),
(half*) c.data_ptr(),
(half*) temp_dq.data_ptr(),
c.size(0), // m
c.size(1), // n
a.size(1), // k
b_gptq_qzeros.size(0), // group number
use_exllama
);
return c;
}
void gptq_shuffle
(
torch::Tensor q_weight,
torch::Tensor q_perm
)
{
const at::cuda::OptionalCUDAGuard device_guard(device_of(q_weight));
vllm::gptq::shuffle_exllama_weight(
(uint32_t*) q_weight.data_ptr(),
q_perm.device().is_meta() ? NULL : (int*) q_perm.data_ptr(),
q_weight.size(0) * 8,
q_weight.size(1)
);
}