hf_text-generation-inference/server/text_generation_server/layers/gptq/triton.py

360 lines
12 KiB
Python

import math
import numpy as np
import torch
import torch.nn as nn
from torch.cuda.amp import custom_fwd
import triton
import triton.language as tl
from . import custom_autotune
# code based https://github.com/fpgaminer/GPTQ-triton
@custom_autotune.autotune(
configs=[
triton.Config(
{
"BLOCK_SIZE_M": 64,
"BLOCK_SIZE_N": 256,
"BLOCK_SIZE_K": 32,
"GROUP_SIZE_M": 8,
},
num_stages=4,
num_warps=4,
),
triton.Config(
{
"BLOCK_SIZE_M": 128,
"BLOCK_SIZE_N": 128,
"BLOCK_SIZE_K": 32,
"GROUP_SIZE_M": 8,
},
num_stages=4,
num_warps=4,
),
triton.Config(
{
"BLOCK_SIZE_M": 64,
"BLOCK_SIZE_N": 128,
"BLOCK_SIZE_K": 32,
"GROUP_SIZE_M": 8,
},
num_stages=4,
num_warps=4,
),
triton.Config(
{
"BLOCK_SIZE_M": 128,
"BLOCK_SIZE_N": 32,
"BLOCK_SIZE_K": 32,
"GROUP_SIZE_M": 8,
},
num_stages=4,
num_warps=4,
),
triton.Config(
{
"BLOCK_SIZE_M": 64,
"BLOCK_SIZE_N": 64,
"BLOCK_SIZE_K": 32,
"GROUP_SIZE_M": 8,
},
num_stages=4,
num_warps=4,
),
triton.Config(
{
"BLOCK_SIZE_M": 64,
"BLOCK_SIZE_N": 128,
"BLOCK_SIZE_K": 32,
"GROUP_SIZE_M": 8,
},
num_stages=2,
num_warps=8,
),
triton.Config(
{
"BLOCK_SIZE_M": 64,
"BLOCK_SIZE_N": 64,
"BLOCK_SIZE_K": 64,
"GROUP_SIZE_M": 8,
},
num_stages=3,
num_warps=8,
),
triton.Config(
{
"BLOCK_SIZE_M": 32,
"BLOCK_SIZE_N": 32,
"BLOCK_SIZE_K": 128,
"GROUP_SIZE_M": 8,
},
num_stages=2,
num_warps=4,
),
],
key=["M", "N", "K"],
nearest_power_of_two=True,
prune_configs_by={
"early_config_prune": custom_autotune.matmul248_kernel_config_pruner,
"perf_model": None,
"top_k": None,
},
)
@triton.jit
def matmul_248_kernel(
a_ptr,
b_ptr,
c_ptr,
scales_ptr,
zeros_ptr,
g_ptr,
M,
N,
K,
bits,
maxq,
stride_am,
stride_ak,
stride_bk,
stride_bn,
stride_cm,
stride_cn,
stride_scales,
stride_zeros,
BLOCK_SIZE_M: tl.constexpr,
BLOCK_SIZE_N: tl.constexpr,
BLOCK_SIZE_K: tl.constexpr,
GROUP_SIZE_M: tl.constexpr,
):
"""
Compute the matrix multiplication C = A x B.
A is of shape (M, K) float16
B is of shape (K//8, N) int32
C is of shape (M, N) float16
scales is of shape (G, N) float16
zeros is of shape (G, N) float16
g_ptr is of shape (K) int32
"""
infearure_per_bits = 32 // bits
pid = tl.program_id(axis=0)
num_pid_m = tl.cdiv(M, BLOCK_SIZE_M)
num_pid_n = tl.cdiv(N, BLOCK_SIZE_N)
num_pid_k = tl.cdiv(K, BLOCK_SIZE_K)
num_pid_in_group = GROUP_SIZE_M * num_pid_n
group_id = pid // num_pid_in_group
first_pid_m = group_id * GROUP_SIZE_M
group_size_m = min(num_pid_m - first_pid_m, GROUP_SIZE_M)
pid_m = first_pid_m + (pid % group_size_m)
pid_n = (pid % num_pid_in_group) // group_size_m
offs_am = pid_m * BLOCK_SIZE_M + tl.arange(0, BLOCK_SIZE_M)
offs_bn = pid_n * BLOCK_SIZE_N + tl.arange(0, BLOCK_SIZE_N)
offs_k = tl.arange(0, BLOCK_SIZE_K)
a_ptrs = a_ptr + (
offs_am[:, None] * stride_am + offs_k[None, :] * stride_ak
) # (BLOCK_SIZE_M, BLOCK_SIZE_K)
a_mask = offs_am[:, None] < M
# b_ptrs is set up such that it repeats elements along the K axis 8 times
b_ptrs = b_ptr + (
(offs_k[:, None] // infearure_per_bits) * stride_bk
+ offs_bn[None, :] * stride_bn
) # (BLOCK_SIZE_K, BLOCK_SIZE_N)
g_ptrs = g_ptr + offs_k
# shifter is used to extract the N bits of each element in the 32-bit word from B
scales_ptrs = scales_ptr + offs_bn[None, :]
zeros_ptrs = zeros_ptr + (offs_bn[None, :] // infearure_per_bits)
shifter = (offs_k % infearure_per_bits) * bits
zeros_shifter = (offs_bn % infearure_per_bits) * bits
accumulator = tl.zeros((BLOCK_SIZE_M, BLOCK_SIZE_N), dtype=tl.float32)
for k in range(0, num_pid_k):
g_idx = tl.load(g_ptrs)
# Fetch scales and zeros; these are per-outfeature and thus reused in the inner loop
scales = tl.load(
scales_ptrs + g_idx[:, None] * stride_scales
) # (BLOCK_SIZE_K, BLOCK_SIZE_N,)
zeros = tl.load(
zeros_ptrs + g_idx[:, None] * stride_zeros
) # (BLOCK_SIZE_K, BLOCK_SIZE_N,)
zeros = (zeros >> zeros_shifter[None, :]) & maxq
zeros = (zeros + 1) & maxq # eventually avoid overflow
a = tl.load(a_ptrs, mask=a_mask, other=0.0) # (BLOCK_SIZE_M, BLOCK_SIZE_K)
b = tl.load(b_ptrs) # (BLOCK_SIZE_K, BLOCK_SIZE_N), but repeated
# Now we need to unpack b (which is N-bit values) into 32-bit values
b = (b >> shifter[:, None]) & maxq # Extract the N-bit values
b = (b - zeros) * scales # Scale and shift
accumulator += tl.dot(a, b)
a_ptrs += BLOCK_SIZE_K
b_ptrs += (BLOCK_SIZE_K // infearure_per_bits) * stride_bk
g_ptrs += BLOCK_SIZE_K
c_ptrs = c_ptr + stride_cm * offs_am[:, None] + stride_cn * offs_bn[None, :]
c_mask = (offs_am[:, None] < M) & (offs_bn[None, :] < N)
tl.store(c_ptrs, accumulator, mask=c_mask)
def matmul248(input, qweight, scales, qzeros, g_idx, bits, maxq):
with torch.cuda.device(input.device):
output = torch.empty(
(input.shape[0], qweight.shape[1]), device=input.device, dtype=torch.float16
)
def grid(META):
return (
triton.cdiv(input.shape[0], META["BLOCK_SIZE_M"])
* triton.cdiv(qweight.shape[1], META["BLOCK_SIZE_N"]),
)
matmul_248_kernel[grid](
input,
qweight,
output,
scales,
qzeros,
g_idx,
input.shape[0],
qweight.shape[1],
input.shape[1],
bits,
maxq,
input.stride(0),
input.stride(1),
qweight.stride(0),
qweight.stride(1),
output.stride(0),
output.stride(1),
scales.stride(0),
qzeros.stride(0),
)
return output
class QuantLinearFunction(torch.autograd.Function):
@staticmethod
@custom_fwd(cast_inputs=torch.float16)
def forward(ctx, input, qweight, scales, qzeros, g_idx, bits, maxq):
output = matmul248(input, qweight, scales, qzeros, g_idx, bits, maxq)
return output
class QuantLinear(nn.Module):
def __init__(self, qweight, qzeros, scales, g_idx, bias, bits, groupsize):
super().__init__()
self.register_buffer("qweight", qweight)
self.register_buffer("qzeros", qzeros)
self.register_buffer("scales", scales)
self.register_buffer("g_idx", g_idx)
if bias is not None:
self.register_buffer("bias", bias)
else:
self.bias = None
if bits not in [2, 4, 8]:
raise NotImplementedError("Only 2,4,8 bits are supported.")
self.bits = bits
self.maxq = 2**self.bits - 1
self.groupsize = groupsize
self.outfeatures = qweight.shape[1]
self.infeatures = qweight.shape[0] * 32 // bits
@classmethod
def new(cls, bits, groupsize, infeatures, outfeatures, bias):
if bits not in [2, 4, 8]:
raise NotImplementedError("Only 2,4,8 bits are supported.")
qweight = torch.zeros((infeatures // 32 * bits, outfeatures), dtype=torch.int32)
qzeros = torch.zeros(
(math.ceil(infeatures / groupsize), outfeatures // 32 * bits),
dtype=torch.int32,
)
scales = torch.zeros(
(math.ceil(infeatures / groupsize), outfeatures), dtype=torch.float16
)
g_idx = torch.tensor(
[i // groupsize for i in range(infeatures)], dtype=torch.int32
)
if bias:
bias = torch.zeros((outfeatures), dtype=torch.float16)
else:
bias = None
return cls(qweight, qzeros, scales, g_idx, bias, bits, groupsize)
def pack(self, linear, scales, zeros, g_idx=None):
self.g_idx = g_idx.clone() if g_idx is not None else self.g_idx
scales = scales.t().contiguous()
zeros = zeros.t().contiguous()
scale_zeros = zeros * scales
self.scales = scales.clone().half()
if linear.bias is not None:
self.bias = linear.bias.clone().half()
intweight = []
for idx in range(self.infeatures):
intweight.append(
torch.round(
(linear.weight.data[:, idx] + scale_zeros[self.g_idx[idx]])
/ self.scales[self.g_idx[idx]]
).to(torch.int)[:, None]
)
intweight = torch.cat(intweight, dim=1)
intweight = intweight.t().contiguous()
intweight = intweight.numpy().astype(np.uint32)
qweight = np.zeros(
(intweight.shape[0] // 32 * self.bits, intweight.shape[1]), dtype=np.uint32
)
i = 0
row = 0
while row < qweight.shape[0]:
if self.bits in [2, 4, 8]:
for j in range(i, i + (32 // self.bits)):
qweight[row] |= intweight[j] << (self.bits * (j - i))
i += 32 // self.bits
row += 1
else:
raise NotImplementedError("Only 2,4,8 bits are supported.")
qweight = qweight.astype(np.int32)
self.qweight = torch.from_numpy(qweight)
zeros -= 1
zeros = zeros.numpy().astype(np.uint32)
qzeros = np.zeros(
(zeros.shape[0], zeros.shape[1] // 32 * self.bits), dtype=np.uint32
)
i = 0
col = 0
while col < qzeros.shape[1]:
if self.bits in [2, 4, 8]:
for j in range(i, i + (32 // self.bits)):
qzeros[:, col] |= zeros[:, j] << (self.bits * (j - i))
i += 32 // self.bits
col += 1
else:
raise NotImplementedError("Only 2,4,8 bits are supported.")
qzeros = qzeros.astype(np.int32)
self.qzeros = torch.from_numpy(qzeros)
def forward(self, x):
out_shape = x.shape[:-1] + (self.outfeatures,)
out = QuantLinearFunction.apply(
x.reshape(-1, x.shape[-1]),
self.qweight,
self.scales,
self.qzeros,
self.g_idx,
self.bits,
self.maxq,
)
out = out + self.bias if self.bias is not None else out
return out.reshape(out_shape)