import os
import torch
import torch.distributed
from torch import nn
from torch.nn import functional as F
from typing import List, Tuple, Optional
from loguru import logger
from functools import lru_cache
from text_generation_server.utils.speculate import get_speculate
HAS_BITS_AND_BYTES = True
try:
import bitsandbytes as bnb
from bitsandbytes.nn import Int8Params, Params4bit
except ImportError:
HAS_BITS_AND_BYTES = False
from accelerate import init_empty_weights
from text_generation_server.utils.gptq.quant_linear import QuantLinear
from text_generation_server.utils.import_utils import (
IS_CUDA_SYSTEM,
IS_ROCM_SYSTEM,
IS_XPU_SYSTEM,
)
if IS_XPU_SYSTEM:
import intel_extension_for_pytorch as ipex
HAS_AWQ = True
try:
from text_generation_server.utils.awq.quantize.qmodule import WQLinear
except ImportError:
HAS_AWQ = False
try:
major, _minor = torch.cuda.get_device_capability()
except Exception:
major = 1
HAS_EXLLAMA = False
CAN_EXLLAMA = major >= 8 or IS_ROCM_SYSTEM
V2 = os.getenv("EXLLAMA_VERSION", "2") == "2"
if os.getenv("DISABLE_EXLLAMA") == "True":
HAS_EXLLAMA = False
elif CAN_EXLLAMA:
try:
if V2:
from text_generation_server.utils.gptq.exllamav2 import (
QuantLinear as ExllamaQuantLinear,
create_exllama_buffers,
set_device,
)
HAS_EXLLAMA = "2"
else:
from text_generation_server.utils.gptq.exllama import (
Ex4bitLinear as ExllamaQuantLinear,
create_exllama_buffers,
set_device,
)
HAS_EXLLAMA = "1"
except ImportError:
pass
HAS_EETQ = False
try:
from EETQ import quant_weights, w8_a16_gemm
HAS_EETQ = True
except ImportError:
pass
# Monkey patching
@classmethod
def load_layer_norm(cls, prefix, weights, eps):
weight = weights.get_tensor(f"{prefix}.weight")
bias = weights.get_tensor(f"{prefix}.bias")
with init_empty_weights():
ln = cls(weight.shape, eps=eps)
ln.weight = nn.Parameter(weight)
ln.bias = nn.Parameter(bias)
return ln
@classmethod
def load_layer_norm_no_bias(cls, prefix, weights, eps):
weight = weights.get_tensor(f"{prefix}.weight")
with init_empty_weights():
ln = cls(weight.shape, eps=eps)
ln.weight = nn.Parameter(weight)
ln.bias = None
return ln
@classmethod
def load_conv2d(cls, prefix, weights, in_channels, out_channels, kernel_size, stride):
weight = weights.get_tensor(f"{prefix}.weight")
bias = weights.get_tensor(f"{prefix}.bias")
with init_empty_weights():
conv2d = cls(
in_channels=in_channels,
out_channels=out_channels,
kernel_size=kernel_size,
stride=stride,
)
conv2d.weight = nn.Parameter(weight)
conv2d.bias = nn.Parameter(bias)
return conv2d
@classmethod
def load_conv2d_no_bias(
cls, prefix, weights, in_channels, out_channels, kernel_size, stride
):
weight = weights.get_tensor(f"{prefix}.weight")
with init_empty_weights():
conv2d = cls(
in_channels=in_channels,
out_channels=out_channels,
kernel_size=kernel_size,
stride=stride,
)
conv2d.weight = nn.Parameter(weight)
conv2d.bias = None
return conv2d
torch.nn.Conv2d.load = load_conv2d
torch.nn.Conv2d.load_no_bias = load_conv2d_no_bias
torch.nn.LayerNorm.load = load_layer_norm
torch.nn.LayerNorm.load_no_bias = load_layer_norm_no_bias
class FastLinear(nn.Module):
def __init__(
self,
weight,
bias,
) -> None:
super().__init__()
self.weight = nn.Parameter(weight)
if bias is not None:
self.bias = nn.Parameter(bias)
else:
self.bias = None
@classmethod
def load(cls, config, prefix: str, weights, bias: bool):
weight = weights.get_tensor(f"{prefix}.weight")
if bias:
bias = weights.get_tensor(f"{prefix}.bias")
else:
bias = None
return cls(weight, bias)
def forward(self, input: torch.Tensor) -> torch.Tensor:
return F.linear(input, self.weight, self.bias)
class EETQLinear(nn.Module):
def __init__(
self,
weight,
bias,
) -> None:
super().__init__()
device = weight.device
if weight.dtype != torch.float16:
weight = weight.to(dtype=torch.float16)
weight = torch.t(weight).contiguous().cpu()
weight, scale = quant_weights(weight, torch.int8, False)
self.weight = weight.cuda(device)
self.scale = scale.cuda(device)
self.bias = bias.cuda(device) if bias is not None else None
def forward(self, input: torch.Tensor) -> torch.Tensor:
output = w8_a16_gemm(input, self.weight, self.scale)
output = output + self.bias if self.bias is not None else output
return output
def fp8_quantize(weight, qdtype=torch.float8_e4m3fn):
device = weight.device
# weight, scale = quant_weights(weight, torch.int8, False)
finfo = torch.finfo(qdtype)
# Calculate the scale as dtype max divided by absmax
scale = finfo.max / weight.abs().max().clamp(min=1e-12)
# scale and clamp the tensor to bring it to
# the representative range of float8 data type
# (as default cast is unsaturated)
qweight = (weight * scale).clamp(min=finfo.min, max=finfo.max)
# Return both float8 data and the inverse scale (as float),
# as both required as inputs to torch._scaled_mm
qweight = qweight.to(qdtype)
scale = scale.float().reciprocal()
return qweight, scale
class Fp8Linear(nn.Module):
def __init__(
self,
weight,
bias,
) -> None:
super().__init__()
self.dtype = weight.dtype
self.qweight, self.scale = fp8_quantize(weight)
self.bias = bias if bias is not None else None
def forward(self, input: torch.Tensor) -> torch.Tensor:
qinput, scale = fp8_quantize(input)
output, _ = torch._scaled_mm(
qinput,
self.qweight.t(),
out_dtype=self.dtype,
scale_a=scale,
scale_b=self.scale,
bias=self.bias,
)
return output
class Linear8bitLt(nn.Module):
def __init__(
self,
weight,
bias,
has_fp16_weights=True,
memory_efficient_backward=False,
threshold=0.0,
index=None,
):
super().__init__()
assert (
not memory_efficient_backward
), "memory_efficient_backward is no longer required and the argument is deprecated in 0.37.0 and will be removed in 0.39.0"
self.state = bnb.MatmulLtState()
self.index = index
# Necessary for stacked layers
self.state.threshold = threshold
self.state.has_fp16_weights = has_fp16_weights
self.state.memory_efficient_backward = memory_efficient_backward
if threshold > 0.0 and not has_fp16_weights:
self.state.use_pool = True
self.weight = Int8Params(
weight.data,
has_fp16_weights=has_fp16_weights,
requires_grad=has_fp16_weights,
)
self.weight.cuda(weight.device)
self.bias = bias
def init_8bit_state(self):
self.state.CB = self.weight.CB
self.state.SCB = self.weight.SCB
self.weight.CB = None
self.weight.SCB = None
def forward(self, x: torch.Tensor):
self.state.is_training = self.training
if self.weight.CB is not None:
self.init_8bit_state()
# weights are cast automatically as Int8Params, but the bias has to be cast manually
if self.bias is not None and self.bias.dtype != x.dtype:
self.bias.data = self.bias.data.to(x.dtype)
out = bnb.matmul(x, self.weight, bias=self.bias, state=self.state)
if not self.state.has_fp16_weights:
if self.state.CB is not None and self.state.CxB is not None:
# we converted 8-bit row major to turing/ampere format in the first inference pass
# we no longer need the row-major weight
del self.state.CB
self.weight.data = self.state.CxB
return out
class Linear4bit(nn.Module):
def __init__(self, weight, bias, quant_type):
super().__init__()
self.weight = Params4bit(
weight.data,
requires_grad=False,
compress_statistics=True,
quant_type=quant_type,
)
self.compute_dtype = None
self.weight.cuda(weight.device)
self.bias = bias
def forward(self, x: torch.Tensor):
# weights are cast automatically as Int8Params, but the bias has to be cast manually
if self.bias is not None and self.bias.dtype != x.dtype:
self.bias.data = self.bias.data.to(x.dtype)
if getattr(self.weight, "quant_state", None) is None:
print(
"FP4 quantization state not initialized. Please call .cuda() or .to(device) on the LinearFP4 layer first."
)
inp_dtype = x.dtype
if self.compute_dtype is not None:
x = x.to(self.compute_dtype)
bias = None if self.bias is None else self.bias.to(self.compute_dtype)
out = bnb.matmul_4bit(
x, self.weight.t(), bias=bias, quant_state=self.weight.quant_state
)
out = out.to(inp_dtype)
return out
@lru_cache(1)
def warn_deprecate_bnb():
logger.warning(
"Bitsandbytes 8bit is deprecated, using `eetq` is a drop-in replacement, and has much better performnce"
)
def get_linear(weight, bias, quantize):
if quantize is None:
linear = FastLinear(weight, bias)
elif quantize == "eetq":
if HAS_EETQ:
linear = EETQLinear(weight, bias)
else:
raise ImportError(
"Please install EETQ from https://github.com/NetEase-FuXi/EETQ"
)
elif quantize == "fp8":
linear = Fp8Linear(weight, bias)
elif quantize == "bitsandbytes":
warn_deprecate_bnb()
linear = Linear8bitLt(
weight,
bias,
has_fp16_weights=False,
threshold=6.0,
)
if bias is not None:
linear.bias = nn.Parameter(bias)
elif quantize == "bitsandbytes-fp4":
linear = Linear4bit(
weight,
bias,
quant_type="fp4",
)
elif quantize == "bitsandbytes-nf4":
linear = Linear4bit(
weight,
bias,
quant_type="nf4",
)
elif quantize == "gptq":
try:
qweight, qzeros, scales, g_idx, bits, groupsize, use_exllama = weight
except Exception:
raise NotImplementedError(
f"The passed weight is not `gptq` compatible, loader needs to be updated."
)
if use_exllama:
linear = ExllamaQuantLinear(
qweight, qzeros, scales, g_idx, bias, bits, groupsize
)
else:
linear = QuantLinear(
qweight,
qzeros,
scales,
g_idx,
bias,
bits,
groupsize,
)
elif quantize == "awq":
try:
qweight, qzeros, scales, _, bits, groupsize, _ = weight
except Exception:
raise NotImplementedError(
f"The passed weight is not `awq` compatible, loader needs to be updated."
)
if IS_ROCM_SYSTEM:
raise NotImplementedError(
"AWQ GEMM kernel can't be used on ROCm systems, please use `--quantize gptq` instead "
"to use Exllama/GPTQ kernels for AWQ inference."
)
if not HAS_AWQ:
raise NotImplementedError(
"You do not seem to have awq installed, either install it (cd server && make install-awq), or try using GPTQ `---quantize gptq` a conversion AWQ->GPTQ will happen on the fly"
)
linear = WQLinear(
w_bit=bits,
group_size=groupsize,
qweight=qweight,
qzeros=qzeros,
scales=scales,
bias=bias is not None,
)
else:
raise NotImplementedError(f"Quantization `{quantize}` is not implemented yet.")
return linear
class SuperLayer(nn.Module):
def __init__(self, linear):
super().__init__()
self.linear = linear
def forward(self, x):
return self.linear.forward(x)
class ResBlock(torch.nn.Module):
def __init__(self, config, prefix, weights):
super().__init__()
self.linear = FastLinear.load(
config, prefix=f"{prefix}.linear", weights=weights, bias=True
)
self.act = torch.nn.SiLU()
def forward(self, x):
return x + self.act(self.linear(x))
class MedusaModel(torch.nn.Module):
def __init__(self, config, medusa_config, weights):
super().__init__()
self.heads = torch.nn.ModuleList(
[
MedusaHead(config, medusa_config, prefix=f"{i}", weights=weights)
for i in range(get_speculate())
]
)
def forward(self, x):
speculative_logits = torch.stack([head(x) for head in self.heads], dim=1)
return speculative_logits
class MedusaHead(torch.nn.Module):
def __init__(self, config, medusa_config, prefix, weights):
super().__init__()
self.blocks = torch.nn.ModuleList(
[
ResBlock(config, prefix=f"{prefix}.{i}", weights=weights)
for i in range(medusa_config["medusa_num_layers"])
]
)
n = len(self.blocks)
self.out = FastLinear.load(
config, prefix=f"{prefix}.{n}", weights=weights, bias=False
)
def forward(self, x):
for block in self.blocks:
x = block(x)
x = self.out(x)
return x
class MedusaHeadV1(nn.Module):
def __init__(self, lm_head, medusa):
super().__init__()
self.lm_head = lm_head
self.medusa = medusa
@staticmethod
def load(config, prefix: str, weights):
from pathlib import Path
from safetensors import safe_open
import json
use_medusa = config.use_medusa
medusa_config = str(Path(use_medusa) / "config.json")
filename = str(Path(use_medusa) / "medusa_lm_head.safetensors")
with open(medusa_config, "r") as f:
medusa_config = json.load(f)
routing = weights.routing
with safe_open(filename, framework="pytorch") as f:
for k in f.keys():
if k in routing and routing[k] != filename:
raise RuntimeError(
f"Key {k} was found in multiple files: {filename} and {routing[k]}"
)
routing[k] = filename
medusa = MedusaModel(config, medusa_config, weights)
lm_head = TensorParallelHead.load(config, prefix, weights)
return MedusaHeadV1(lm_head, medusa)
def forward(
self, input: torch.Tensor
) -> Tuple[torch.Tensor, Optional[torch.Tensor]]:
logits = self.lm_head(input)
# If we have too many tokens, we skip speculative logits
if input.shape[0] > 128:
return logits, None
speculative_logits = self.medusa(input)
return logits, speculative_logits
class MedusaHeadV2(nn.Module):
def __init__(self, config, prefix, weights):
super().__init__()
from pathlib import Path
from safetensors import safe_open
import json
use_medusa = config.use_medusa
medusa_config = str(Path(use_medusa) / "config.json")
filename = str(Path(use_medusa) / "medusa_lm_head.safetensors")
with open(medusa_config, "r") as f:
medusa_config = json.load(f)
routing = weights.routing
with safe_open(filename, framework="pytorch") as f:
for k in f.keys():
if k in routing and routing[k] != filename:
raise RuntimeError(
f"Key {k} was found in multiple files: {filename} and {routing[k]}"
)
routing[k] = filename
self.n_medusa_heads = get_speculate()
assert medusa_config["medusa_num_layers"] == 1
self.linear = TensorParallelColumnLinear.load_multi(
config,
prefixes=[f"{i}.0.linear" for i in range(self.n_medusa_heads)],
dim=0,
weights=weights,
bias=True,
)
self.process_group = weights.process_group
self.world_size = self.process_group.size()
self.rank = self.process_group.rank()
self.act = torch.nn.SiLU()
self.lm_head = TensorParallelHead.load(config, prefix, weights)
def forward(self, x):
# If we have too many tokens, we skip speculative logits
if x.shape[0] > 128:
logits = self.lm_head(x)
return logits, None
size = x.shape[-1]
block_size = (size + self.world_size - 1) // self.world_size
start = self.rank * block_size
stop = (self.rank + 1) * block_size
x_block = x[:, start:stop]
# Compute all medusa heads at the same time, then reshape and move the n_medusa_heads dim to dim 1
medusa_res = self.act(self.linear(x)).reshape(
*x_block.shape[:-1], self.n_medusa_heads, x_block.shape[-1]
)
# Apply all residual medusa heads
output = x[:, start:stop].unsqueeze(-2) + medusa_res
# Gather medusa heads
world_output = [
torch.empty_like(output) for _ in range(self.process_group.size())
]
torch.distributed.all_gather(world_output, output, group=self.process_group)
world_output = torch.cat(world_output, dim=-1)
# Stack x and medusa residual x
stacked_x = torch.cat([x.unsqueeze(-2), world_output], dim=-2)
# Compute lm head on x + medusa residual x
logits = self.lm_head(stacked_x)
# Finally, split logits from speculative logits
logits, speculative_logits = torch.split(
logits, [1, self.n_medusa_heads], dim=-2
)
# Squeeze added dimension
logits = logits.squeeze(-2)
return logits, speculative_logits
class SpeculativeHead(nn.Module):
def __init__(self, lm_head, medusa):
super().__init__()
self.head = lm_head
self.medusa = medusa
@staticmethod
def load(config, prefix: str, weights):
use_medusa = config.use_medusa
if use_medusa:
lm_head = None
try:
medusa = MedusaHeadV1.load(config, prefix, weights)
except:
medusa = MedusaHeadV2(config, prefix, weights)
else:
lm_head = TensorParallelHead.load(config, prefix, weights)
medusa = None
return SpeculativeHead(lm_head, medusa)
def forward(
self, input: torch.Tensor
) -> Tuple[torch.Tensor, Optional[torch.Tensor]]:
if self.medusa is not None:
return self.medusa(input)
assert self.head is not None
logits = self.head(input)
return logits, None
class TensorParallelHead(SuperLayer):
def __init__(self, linear, process_group, should_gather: bool):
super().__init__(linear)
self.process_group = process_group
self.should_gather = should_gather
@staticmethod
def load(config, prefix: str, weights):
if weights.process_group.size() > 1:
try:
weight = weights.get_sharded(f"{prefix}.weight", dim=0)
should_gather = True
except AssertionError:
# If the vocab size is not divisible by number of shards
# just load the entire thing.
weight = weights.get_tensor(f"{prefix}.weight")
should_gather = False
else:
weight = weights.get_tensor(f"{prefix}.weight")
should_gather = False
# GPTQ,AWQ,EETQ don't quantize heads (nor embeddings)
if config.quantize in ["gptq", "awq", "eetq"]:
quantize = None
else:
quantize = config.quantize
return TensorParallelHead(
get_linear(weight, bias=None, quantize=quantize),
process_group=weights.process_group,
should_gather=should_gather,
)
def forward(self, input: torch.Tensor) -> torch.Tensor:
if not self.should_gather:
return super().forward(input)
world_size = self.process_group.size()
if len(input.shape) == 2 and isinstance(self.linear, FastLinear):
out_dim = self.linear.weight.shape[0]
if input.shape[0] == 1:
world_out = input.new_empty(1, out_dim * world_size)
local_out = input.new_empty(1, out_dim)
gather_input = local_out
else:
world_out = input.new_empty(out_dim * world_size, input.shape[0])
gather_input = input.new_empty(out_dim, input.shape[0])
local_out = gather_input.T
torch.mm(input, self.linear.weight.T, out=local_out)
torch.distributed.all_gather_into_tensor(
world_out, gather_input, group=self.process_group
)
if input.shape[0] == 1:
return world_out
return world_out.T
output = super().forward(input)
world_output = [
torch.empty_like(output) for _ in range(self.process_group.size())
]
torch.distributed.all_gather(world_output, output, group=self.process_group)
world_output = torch.cat(world_output, dim=-1)
return world_output
class TensorParallelColumnLinear(SuperLayer):
@classmethod
def load_gate_up(cls, config, prefix: str, weights, bias: bool):
"""Specific method when the QKV was joined after the fact"""
weight = weights.get_weights_col_packed_gate_up(
prefix, quantize=config.quantize
)
if bias:
raise NotImplementedError("packed_gate_up only implemented without bias")
else:
bias = None
linear = get_linear(weight, bias, config.quantize)
return cls(linear)
@classmethod
def load_qkv(cls, config, prefix: str, weights, bias: bool):
"""Specific method when the QKV was joined after the fact"""
weight = weights.get_weights_col_packed_qkv(prefix, quantize=config.quantize)
if bias:
raise NotImplementedError("packed_qkv only implemented for baichuan")
else:
bias = None
linear = get_linear(weight, bias, config.quantize)
return cls(linear)
@classmethod
def load(cls, config, prefix: str, weights, bias: bool):
return cls.load_multi(config, [prefix], weights, bias, dim=0)
@classmethod
def load_multi(cls, config, prefixes: List[str], weights, bias: bool, dim: int):
weight = weights.get_multi_weights_col(
prefixes, quantize=config.quantize, dim=dim
)
if bias:
b = [weights.get_sharded(f"{p}.bias", dim=0) for p in prefixes]
bias = torch.cat(b, dim=dim)
else:
bias = None
linear = get_linear(weight, bias, config.quantize)
return cls(linear)
class TensorParallelRowLinear(SuperLayer):
def __init__(self, linear, process_group):
super().__init__(linear)
self.process_group = process_group
@classmethod
def load(cls, config, prefix: str, weights, bias: bool):
weight = weights.get_multi_weights_row(prefix, quantize=config.quantize)
if bias and weights.process_group.rank() == 0:
# Rank is only on the first rank process
bias = weights.get_tensor(f"{prefix}.bias")
else:
bias = None
return cls(
get_linear(weight, bias, config.quantize),
process_group=weights.process_group,
)
def forward(self, input: torch.Tensor, reduce: bool = True) -> torch.Tensor:
out = super().forward(input)
if self.process_group.size() > 1 and reduce:
torch.distributed.all_reduce(out, group=self.process_group)
return out
class TensorParallelEmbedding(nn.Module):
def __init__(self, prefix: str, weights, reduce=True):
super().__init__()
weight = weights.get_partial_sharded(f"{prefix}.weight", dim=0)
num_embeddings = weights.get_shape(f"{prefix}.weight")[0]
process_group = weights.process_group
world_size = process_group.size()
rank = process_group.rank()
block_size = (num_embeddings + world_size - 1) // world_size
self.min_id = rank * block_size
self.max_id = min(num_embeddings, (rank + 1) * block_size)
self.null_idx = weight.shape[
0
] # Usually block_size, might be less in non even vocab_size.
self.process_group = weights.process_group
self.reduce = reduce
"""Additional 0 entry used for masking"""
self.weight = nn.Parameter(F.pad(weight, (0, 0, 0, 1)))
def forward(self, input: torch.Tensor) -> torch.Tensor:
# default all out of bounds values to `self.null_idx` that will then be mapped to 0
# translate for [0, self.max_id - self.min_id[
input = torch.where(
(self.min_id > input) | (input >= self.max_id),
self.null_idx,
input - self.min_id,
)
out = torch.nn.functional.embedding(input, self.weight)
if self.reduce and self.process_group.size() > 1:
torch.distributed.all_reduce(out, group=self.process_group)
return out
try:
if IS_CUDA_SYSTEM:
import dropout_layer_norm
elif IS_ROCM_SYSTEM:
from vllm import layernorm_ops
else:
dropout_layer_norm = None
class FastLayerNorm(nn.LayerNorm):
def forward(self, hidden_states, residual=None):
if IS_XPU_SYSTEM:
res_out = hidden_states
out = ipex.llm.functional.add_layer_norm(
residual, hidden_states, self.weight, self.bias, self.eps, True
)
if residual is not None:
res_out = residual
return out, res_out
elif hidden_states.shape[-1] > 8192 or IS_ROCM_SYSTEM:
if residual is not None:
hidden_states += residual
residual = hidden_states
return super(FastLayerNorm, self).forward(hidden_states), residual
else:
(
normed_hidden_states,
residual,
*rest,
) = dropout_layer_norm.dropout_add_ln_fwd(
hidden_states,
residual,
self.weight,
self.bias,
None,
None,
None,
None,
0.0,
self.eps,
1.0,
0,
None,
False,
False,
)
if residual is None:
residual = hidden_states
return normed_hidden_states, residual
class FastRMSNorm(nn.Module):
def __init__(self, weight: torch.Tensor, eps: float):
super().__init__()
self.weight = nn.Parameter(weight)
self.variance_epsilon = eps
@classmethod
def load(cls, prefix, weights, eps=1e-6):
weight = weights.get_tensor(f"{prefix}.weight")
return cls(weight, eps)
def forward(self, hidden_states, residual=None):
if IS_XPU_SYSTEM:
residual_out = hidden_states
out = ipex.llm.functional.add_rms_norm(
residual,
hidden_states,
self.weight,
None,
self.variance_epsilon,
True,
)
if residual is not None:
residual_out = residual
return out, residual_out
elif hidden_states.shape[-1] > 8192:
if residual is not None:
hidden_states += residual
residual = hidden_states
hidden_states = hidden_states.to(torch.float32)
variance = hidden_states.pow(2).mean(-1, keepdim=True)
hidden_states = hidden_states * torch.rsqrt(
variance + self.variance_epsilon
)
# convert into half-precision if necessary
if self.weight.dtype in [torch.float16, torch.bfloat16]:
hidden_states = hidden_states.to(self.weight.dtype)
return self.weight * hidden_states, residual
elif IS_CUDA_SYSTEM:
# faster post attention rms norm
(
normed_hidden_states,
res,
*rest,
) = dropout_layer_norm.dropout_add_ln_fwd(
hidden_states,
residual,
self.weight,
None,
None,
None,
None,
None,
0.0,
self.variance_epsilon,
1.0,
0,
None,
False,
True, # Activate RMSNorm
)
if res is None:
res = hidden_states
return normed_hidden_states, res
elif IS_ROCM_SYSTEM:
# We use VLLM RMSNorm kernel that can be compiled for RoCm, instead of Flash Attention ones that can not.
if residual is not None:
hidden_states += residual
residual = hidden_states
out = torch.empty_like(hidden_states)
layernorm_ops.rms_norm(
out,
hidden_states,
self.weight.data,
self.variance_epsilon,
)
return out, residual
else:
raise ValueError(
"Your system seem to be not supported. Please check your install or open an issue at https://github.com/huggingface/text-generation-inference/issues with a clear reproduction."
)
except ImportError:
pass
try:
if IS_CUDA_SYSTEM:
from flash_attn.layers.rotary import RotaryEmbedding
import rotary_emb
elif IS_ROCM_SYSTEM:
from vllm import pos_encoding_ops
def _create_inv_freq(dim, base, device):
inv_freq = 1.0 / (
base ** (torch.arange(0, dim, 2, device=device, dtype=torch.float32) / dim)
)
return inv_freq
def _get_rope_config(config):
if os.getenv("ROPE_SCALING", None) is not None:
rope_scaling = {
"type": os.environ["ROPE_SCALING"],
"factor": float(os.environ["ROPE_FACTOR"]),
}
return rope_scaling
return getattr(config, "rope_scaling", None)
class PositionRotaryEmbedding(nn.Module):
def __init__(self, inv_freq, scaling_factor):
super().__init__()
self.inv_freq = inv_freq
self._seq_len_cached = 0
self._cos_cached = None
self._sin_cached = None
self._cos_k_cached = None
self._sin_k_cached = None
self.scaling_factor = scaling_factor
self.dynamic_args = None
def forward(
self,
query: torch.Tensor,
key: torch.Tensor,
cos: torch.Tensor,
sin: torch.Tensor,
):
# Such controlflows may add some overhead.
if IS_CUDA_SYSTEM:
rotary_dim = cos.shape[-1]
q1 = query[..., :rotary_dim]
q2 = query[..., rotary_dim : 2 * rotary_dim]
rotary_emb.apply_rotary(q1, q2, cos, sin, q1, q2, False)
k1 = key[..., :rotary_dim]
k2 = key[..., rotary_dim : 2 * rotary_dim]
rotary_emb.apply_rotary(k1, k2, cos, sin, k1, k2, False)
elif IS_ROCM_SYSTEM:
# NOTE: On RoCm systems, we use a ROPE implementatation adapted from VLLM which launches a single kernel for both query/key, contrary to flash-attn implementation used on NVIDIA systems.
# Compiling flash-attn rotary on RoCm, it appears hipcc is unable to unroll loops, resulting in an even slower inference compared to eager: https://github.com/pytorch/pytorch/issues/113773
head_size = query.shape[-1]
# Inplace operation, updating query and key.
pos_encoding_ops.rotary_embedding(query, key, head_size, cos, sin, True)
elif IS_XPU_SYSTEM:
ipex.llm.functional.rotary_embedding(
query, key, sin, cos, query.size(-1), True
)
else:
raise ValueError(
"Your system seem to be not supported. Please check your install or open an issue at https://github.com/huggingface/text-generation-inference/issues with a clear reproduction."
)
@classmethod
def static(cls, config, dim, base, device):
inv_freq = _create_inv_freq(dim, base, device)
scaling_factor = None
rope_scaling = _get_rope_config(config)
if rope_scaling is not None:
scaling_factor = rope_scaling["factor"]
if rope_scaling["type"] == "linear":
pass
elif rope_scaling["type"] == "dynamic":
return DynamicPositionRotaryEmbedding(
dim=dim,
max_position_embeddings=config.max_position_embeddings,
base=base,
device=inv_freq.device,
scaling_factor=scaling_factor,
)
elif rope_scaling["type"] == "yarn":
return YarnPositionRotaryEmbedding(
dim=2 * inv_freq.shape[0],
max_position_embeddings=rope_scaling[
"original_max_position_embeddings"
],
base=10000.0,
device=inv_freq.device,
scaling_factor=scaling_factor,
extrapolation_factor=1,
attn_factor=1,
beta_fast=32,
beta_slow=1,
)
else:
raise NotImplementedError(
f"rope scaling type {rope_scaling['type']} is not implemented or invalid"
)
return cls(inv_freq, scaling_factor)
@classmethod
def load(cls, config, prefix, weights):
# XXX: Always load this in float32 !
dtype = weights.dtype
weights.dtype = torch.float32
inv_freq = weights.get_tensor(f"{prefix}.inv_freq")
weights.dtype = dtype
scaling_factor = None
rope_scaling = _get_rope_config(config)
if rope_scaling is not None:
scaling_factor = rope_scaling["factor"]
if rope_scaling["type"] == "linear":
pass
elif rope_scaling["type"] == "dynamic":
return DynamicPositionRotaryEmbedding(
dim=2 * inv_freq.shape[0],
max_position_embeddings=config.max_position_embeddings,
base=10000.0,
device=inv_freq.device,
scaling_factor=scaling_factor,
)
elif rope_scaling["type"] == "yarn":
return YarnPositionRotaryEmbedding(
dim=2 * inv_freq.shape[0],
max_position_embeddings=rope_scaling[
"original_max_position_embeddings"
],
base=10000.0,
device=inv_freq.device,
scaling_factor=scaling_factor,
extrapolation_factor=1,
attn_factor=1,
beta_fast=32,
beta_slow=1,
)
else:
raise NotImplementedError(
f"rope scaling type {rope_scaling['type']} is not implemented or invalid"
)
return cls(inv_freq, scaling_factor)
def _update_cos_sin_cache(self, dtype, device, seqlen):
# Reset the tables if the sequence length has changed,
# or if we're on a new device (possibly due to tracing for instance)
if (
seqlen > self._seq_len_cached
or self._cos_cached.device != device
or self._cos_cached.dtype != dtype
):
self._seq_len_cached = seqlen
t = torch.arange(seqlen, device=device, dtype=self.inv_freq.dtype)
if self.scaling_factor is not None:
t /= self.scaling_factor
# Don't do einsum, it converts fp32 to fp16
# freqs = torch.einsum("i,j->ij", t, self.inv_freq)
freqs = torch.outer(t, self.inv_freq.to(device=t.device))
self._cos_cached = torch.cos(freqs).to(dtype)
self._sin_cached = torch.sin(freqs).to(dtype)
def get_cos_sin(
self, position_ids: torch.Tensor, max_s: int, dtype: torch.dtype
):
"""
Return cos and sin for the asked position ids
"""
if IS_ROCM_SYSTEM:
# For RoCm, we always use float cos/sin to avoid a cast.
# For NVIDIA, for some reason, the flash-attn rotary kernel requires cos/sin and query/key to be of same dtype: https://github.com/Dao-AILab/flash-attention/blob/017716451d446e464dde9aca3a3c1ed2209caaa9/csrc/rotary/rotary.cpp#L26
# But later on goes and cast cos/sin to float anyway: https://github.com/Dao-AILab/flash-attention/blob/017716451d446e464dde9aca3a3c1ed2209caaa9/csrc/rotary/rotary_cuda.cu#L29, which looks suboptimal.
dtype = torch.float32
self._update_cos_sin_cache(dtype, position_ids.device, max_s)
cos = torch.index_select(self._cos_cached, 0, position_ids)
sin = torch.index_select(self._sin_cached, 0, position_ids)
# Note: this unsqueeze is not necessary on RoCm + VLLM ROPE implementation, but we leave it as is to avoid yet an other controlflow.
return cos.unsqueeze(1), sin.unsqueeze(1)
class DynamicPositionRotaryEmbedding(PositionRotaryEmbedding):
def __init__(self, dim, max_position_embeddings, base, device, scaling_factor):
inv_freq = _create_inv_freq(dim, base, device)
super().__init__(inv_freq, scaling_factor)
self.dim = dim
self.max_position_embeddings = max_position_embeddings
self.base = base
def _update_cos_sin_cache(self, dtype, device, seqlen):
# Reset the tables if the sequence length has changed,
# or if we're on a new device (possibly due to tracing for instance)
if (
seqlen > self._seq_len_cached
or self._cos_cached.device != device
or self._cos_cached.dtype != dtype
):
if seqlen > self.max_position_embeddings:
newbase = self.base * (
(self.scaling_factor * seqlen / self.max_position_embeddings)
- (self.scaling_factor - 1)
) ** (self.dim / (self.dim - 2))
self.inv_freq = _create_inv_freq(
self.dim, newbase, self.inv_freq.device
)
self._seq_len_cached = seqlen
t = torch.arange(seqlen, device=device, dtype=self.inv_freq.dtype)
# Don't do einsum, it converts fp32 to fp16
# freqs = torch.einsum("i,j->ij", t, self.inv_freq)
freqs = torch.outer(t, self.inv_freq.to(device=t.device))
self._cos_cached = torch.cos(freqs).to(dtype)
self._sin_cached = torch.sin(freqs).to(dtype)
# Inverse dim formula to find dim based on number of rotations
import math
def find_correction_dim(
num_rotations, dim, base=10000, max_position_embeddings=2048
):
return (
dim * math.log(max_position_embeddings / (num_rotations * 2 * math.pi))
) / (2 * math.log(base))
# Find dim range bounds based on rotations
def find_correction_range(
low_rot, high_rot, dim, base=10000, max_position_embeddings=2048
):
low = math.floor(
find_correction_dim(low_rot, dim, base, max_position_embeddings)
)
high = math.ceil(
find_correction_dim(high_rot, dim, base, max_position_embeddings)
)
return max(low, 0), min(high, dim - 1) # Clamp values just in case
def linear_ramp_mask(min, max, dim):
if min == max:
max += 0.001 # Prevent singularity
linear_func = (torch.arange(dim, dtype=torch.float32) - min) / (max - min)
ramp_func = torch.clamp(linear_func, 0, 1)
return ramp_func
def get_mscale(scale=1):
if scale <= 1:
return 1.0
return 0.1 * math.log(scale) + 1.0
class YarnPositionRotaryEmbedding(PositionRotaryEmbedding):
def __init__(
self,
dim,
max_position_embeddings,
base,
device,
scaling_factor,
*,
extrapolation_factor,
attn_factor,
beta_fast,
beta_slow,
):
inv_freq = _create_inv_freq(dim, base, device)
super().__init__(inv_freq, scaling_factor)
self.dim = dim
self.max_position_embeddings = max_position_embeddings
self.base = base
self.extrapolation_factor = extrapolation_factor
self.attn_factor = attn_factor
self.beta_fast = beta_fast
self.beta_slow = beta_slow
self.mscale = float(
get_mscale(self.scaling_factor) * self.attn_factor
) # Get n-d magnitude scaling corrected for interpolation
def _update_cos_sin_cache(self, dtype, device, seqlen):
# Reset the tables if the sequence length has changed,
# or if we're on a new device (possibly due to tracing for instance)
if (
seqlen > self._seq_len_cached
or self._cos_cached.device != device
or self._cos_cached.dtype != dtype
):
if seqlen > self.max_position_embeddings:
inv_freq_extrapolation = _create_inv_freq(
self.dim, self.base, self.inv_freq.device
)
freqs = 1.0 / inv_freq_extrapolation
inv_freq_interpolation = 1.0 / (self.scaling_factor * freqs)
low, high = find_correction_range(
self.beta_fast,
self.beta_slow,
self.dim,
self.base,
self.max_position_embeddings,
)
inv_freq_mask = (
1
- linear_ramp_mask(low, high, self.dim // 2).float().to(device)
) * self.extrapolation_factor # Get n-d rotational scaling corrected for extrapolation
inv_freq = (
inv_freq_interpolation * (1 - inv_freq_mask)
+ inv_freq_extrapolation * inv_freq_mask
)
self.inv_freq = inv_freq
self.mscale = float(
get_mscale(self.scaling_factor) * self.attn_factor
) # Get n-d magnitude scaling corrected for interpolation
self._seq_len_cached = seqlen
t = torch.arange(seqlen, device=device, dtype=self.inv_freq.dtype)
# Don't do einsum, it converts fp32 to fp16
# freqs = torch.einsum("i,j->ij", t, self.inv_freq)
freqs = torch.outer(t, self.inv_freq.to(device=t.device))
self._cos_cached = (torch.cos(freqs) * self.mscale).to(dtype)
self._sin_cached = (torch.sin(freqs) * self.mscale).to(dtype)
except ImportError:
pass