Witllm/qwen/modeling_qwen.py

1581 lines
66 KiB
Python
Raw Normal View History

2024-01-03 20:26:26 +08:00
# Copyright (c) Alibaba Cloud.
#
# This source code is licensed under the license found in the
# LICENSE file in the root directory of this source tree.
import copy
import importlib
import math
import inspect
2024-01-03 20:26:26 +08:00
import pathlib
from typing import TYPE_CHECKING, Optional, Tuple, Union, Callable, List, Any, Generator
import torch
import torch.nn.functional as F
import torch.utils.checkpoint
import warnings
from torch.nn import CrossEntropyLoss
from transformers import PreTrainedTokenizer, GenerationConfig, StoppingCriteriaList
from transformers.generation.logits_process import LogitsProcessorList
if TYPE_CHECKING:
from transformers.generation.streamers import BaseStreamer
from transformers.generation.utils import GenerateOutput
from transformers.modeling_outputs import (
BaseModelOutputWithPast,
CausalLMOutputWithPast,
)
from transformers.modeling_utils import PreTrainedModel
from transformers.utils import logging
try:
from einops import rearrange
except ImportError:
rearrange = None
from torch import nn
SUPPORT_CUDA = torch.cuda.is_available()
SUPPORT_BF16 = SUPPORT_CUDA and torch.cuda.is_bf16_supported()
SUPPORT_FP16 = SUPPORT_CUDA and torch.cuda.get_device_capability(0)[0] >= 7
SUPPORT_TORCH2 = hasattr(torch, '__version__') and int(torch.__version__.split(".")[0]) >= 2
2024-01-03 21:03:27 +08:00
from configuration_qwen import QWenConfig
from qwen_generation_utils import (
2024-01-03 20:26:26 +08:00
HistoryType,
make_context,
decode_tokens,
get_stop_words_ids,
StopWordsLogitsProcessor,
)
logger = logging.get_logger(__name__)
QWen_PRETRAINED_MODEL_ARCHIVE_LIST = ["qwen-7b"]
_ERROR_BAD_CHAT_FORMAT = """\
We detect you are probably using the pretrained model (rather than chat model) for chatting, since the chat_format in generation_config is not "chatml".
If you are directly using the model downloaded from Huggingface, please make sure you are using our "Qwen/Qwen-7B-Chat" Huggingface model (rather than "Qwen/Qwen-7B") when you call model.chat().
我们检测到您可能在使用预训练模型而非chat模型进行多轮chat因为您当前在generation_config指定的chat_format并未设置为我们在对话中所支持的"chatml"格式
如果您在直接使用我们从Huggingface提供的模型请确保您在调用model.chat()使用的是"Qwen/Qwen-7B-Chat"模型而非"Qwen/Qwen-7B"预训练模型
"""
_SENTINEL = object()
_ERROR_STREAM_IN_CHAT = """\
Pass argument `stream` to model.chat() is buggy, deprecated, and marked for removal. Please use model.chat_stream(...) instead of model.chat(..., stream=True).
向model.chat()传入参数stream的用法可能存在Bug该用法已被废弃将在未来被移除请使用model.chat_stream(...)代替model.chat(..., stream=True)
"""
apply_rotary_emb_func = None
rms_norm = None
def quantize_cache_v(fdata, bits, qmax, qmin):
# b, s, head, h-dim->b, head, s, h-dim
qtype = torch.uint8
device = fdata.device
shape = fdata.shape
fdata_cal = torch.flatten(fdata, 2)
fmax = torch.amax(fdata_cal, dim=-1, keepdim=True)
fmin = torch.amin(fdata_cal, dim=-1, keepdim=True)
# Compute params
if qmax.device != fmax.device:
qmax = qmax.to(device)
qmin = qmin.to(device)
scale = (fmax - fmin) / (qmax - qmin)
zero = qmin - fmin / scale
scale = scale.unsqueeze(-1).repeat(1,1,shape[2],1).contiguous()
zero = zero.unsqueeze(-1).repeat(1,1,shape[2],1).contiguous()
# Quantize
res_data = fdata / scale + zero
qdata = torch.clamp(res_data, qmin, qmax).to(qtype)
return qdata.contiguous(), scale, zero
def dequantize_cache_torch(qdata, scale, zero):
data = scale * (qdata - zero)
return data
class QWenAttention(nn.Module):
def __init__(self, config):
super().__init__()
self.register_buffer("masked_bias", torch.tensor(-1e4), persistent=False)
self.seq_length = config.seq_length
self.hidden_size = config.hidden_size
self.split_size = config.hidden_size
self.num_heads = config.num_attention_heads
self.head_dim = self.hidden_size // self.num_heads
self.scale_attn_weights = True
self.projection_size = config.kv_channels * config.num_attention_heads
assert self.projection_size % config.num_attention_heads == 0
self.hidden_size_per_attention_head = (
self.projection_size // config.num_attention_heads
)
self.c_attn = nn.Linear(config.hidden_size, 3 * self.projection_size)
self.c_proj = nn.Linear(
config.hidden_size, self.projection_size, bias=not config.no_bias
)
self.is_fp32 = not (config.bf16 or config.fp16)
2024-01-07 16:22:41 +08:00
2024-01-03 20:26:26 +08:00
self.bf16 = config.bf16
self.use_dynamic_ntk = config.use_dynamic_ntk
self.use_logn_attn = config.use_logn_attn
logn_list = [
math.log(i, self.seq_length) if i > self.seq_length else 1
for i in range(1, 32768)
]
logn_tensor = torch.tensor(logn_list)[None, :, None, None]
self.register_buffer("logn_tensor", logn_tensor, persistent=False)
self.attn_dropout = nn.Dropout(config.attn_dropout_prob)
self.softmax_in_fp32 = config.softmax_in_fp32 if hasattr(config, 'softmax_in_fp32') else False
self.use_cache_quantization = config.use_cache_quantization if hasattr(config, 'use_cache_quantization') else False
self.use_cache_kernel = config.use_cache_kernel if hasattr(config,'use_cache_kernel') else False
cache_dtype = torch.float
if self.bf16:
cache_dtype=torch.bfloat16
elif config.fp16:
cache_dtype = torch.float16
self.cache_qmax = torch.tensor(torch.iinfo(torch.uint8).max, dtype=cache_dtype)
self.cache_qmin = torch.tensor(torch.iinfo(torch.uint8).min, dtype=cache_dtype)
if config.use_cache_quantization and config.use_cache_kernel:
# pre check if the support files existing
module_root = pathlib.Path(__file__).parent
src_files = ("cache_autogptq_cuda_256.cpp", "cache_autogptq_cuda_kernel_256.cu")
if any(not (module_root/src).is_file() for src in src_files):
warnings.warn("KV cache kernel source files (.cpp and .cu) not found.")
self.cache_kernels = None
else:
try:
from .cpp_kernels import cache_autogptq_cuda_256
self.cache_kernels = cache_autogptq_cuda_256
except ImportError:
warnings.warn("Failed to import KV cache kernels.")
self.cache_kernels = None
def _attn(self, query, key, value, causal_mask=None, attention_mask=None, head_mask=None):
device = query.device
if self.use_cache_quantization:
qk, qk_scale, qk_zero = key
if self.use_cache_kernel and self.cache_kernels is not None:
shape = query.shape[:-1] + (qk.shape[-2],)
attn_weights = torch.zeros(shape, dtype=torch.float16, device=device)
self.cache_kernels.vecquant8matmul_batched_faster_old(
query.contiguous() if query.dtype == torch.float16 else query.to(torch.float16).contiguous(),
qk.transpose(-1, -2).contiguous(),
attn_weights,
qk_scale.contiguous() if qk_scale.dtype == torch.float16 else qk_scale.to(torch.float16).contiguous(),
qk_zero.contiguous()if qk_zero.dtype == torch.float16 else qk_zero.to(torch.float16).contiguous())
# attn_weights = attn_weights.to(query.dtype).contiguous()
else:
key = dequantize_cache_torch(qk, qk_scale, qk_zero)
attn_weights = torch.matmul(query, key.transpose(-1, -2))
else:
attn_weights = torch.matmul(query, key.transpose(-1, -2))
if self.scale_attn_weights:
if self.use_cache_quantization:
size_temp = value[0].size(-1)
else:
size_temp = value.size(-1)
attn_weights = attn_weights / (size_temp ** 0.5)
mask_value = torch.finfo(attn_weights.dtype).min
if causal_mask is not None:
attn_weights = torch.where(
causal_mask, attn_weights.to(attn_weights.dtype), mask_value
)
if attention_mask is not None:
attn_weights = attn_weights + attention_mask
if self.softmax_in_fp32:
attn_weights = nn.functional.softmax(attn_weights.float(), dim=-1)
else:
attn_weights = nn.functional.softmax(attn_weights, dim=-1)
attn_weights = attn_weights.type(query.dtype)
attn_weights = self.attn_dropout(attn_weights)
if head_mask is not None:
attn_weights = attn_weights * head_mask
if self.use_cache_quantization:
qv, qv_scale, qv_zero = value
if self.use_cache_kernel and self.cache_kernels is not None:
shape = attn_weights.shape[:-1] + (query.shape[-1],)
attn_output = torch.zeros(shape, dtype=torch.float16, device=device)
self.cache_kernels.vecquant8matmul_batched_column_compression_faster_old(
attn_weights.contiguous() if attn_weights.dtype == torch.float16 else attn_weights.to(torch.float16).contiguous(),
qv.contiguous(), # dtype: int32
attn_output,
qv_scale.contiguous() if qv_scale.dtype == torch.float16 else qv_scale.to(torch.float16).contiguous(),
qv_zero.contiguous() if qv_zero.dtype == torch.float16 else qv_zero.to(torch.float16).contiguous())
if attn_output.dtype != query.dtype:
attn_output = attn_output.to(query.dtype)
attn_weights = attn_weights.to(query.dtype)
else:
value = dequantize_cache_torch(qv, qv_scale, qv_zero)
attn_output = torch.matmul(attn_weights, value)
else:
attn_output = torch.matmul(attn_weights, value)
attn_output = attn_output.transpose(1, 2)
return attn_output, attn_weights
def _split_heads(self, tensor, num_heads, attn_head_size):
new_shape = tensor.size()[:-1] + (num_heads, attn_head_size)
tensor = tensor.view(new_shape)
return tensor
def _merge_heads(self, tensor, num_heads, attn_head_size):
tensor = tensor.contiguous()
new_shape = tensor.size()[:-2] + (num_heads * attn_head_size,)
return tensor.view(new_shape)
def forward(
self,
hidden_states: Optional[Tuple[torch.FloatTensor]],
rotary_pos_emb_list: Optional[List[List[torch.Tensor]]] = None,
layer_past: Optional[Tuple[torch.Tensor]] = None,
attention_mask: Optional[torch.FloatTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
encoder_hidden_states: Optional[torch.Tensor] = None,
encoder_attention_mask: Optional[torch.FloatTensor] = None,
output_attentions: Optional[bool] = False,
use_cache: Optional[bool] = False,
):
mixed_x_layer = self.c_attn(hidden_states)
query, key, value = mixed_x_layer.split(self.split_size, dim=2)
query = self._split_heads(query, self.num_heads, self.head_dim)
key = self._split_heads(key, self.num_heads, self.head_dim)
value = self._split_heads(value, self.num_heads, self.head_dim)
if rotary_pos_emb_list is not None:
cur_len = query.shape[1]
if len(rotary_pos_emb_list) == 1:
rotary_pos_emb = rotary_pos_emb_list[0]
rotary_pos_emb = [i[:, -cur_len:, :, :] for i in rotary_pos_emb]
rotary_pos_emb = (rotary_pos_emb,) * 2
q_pos_emb, k_pos_emb = rotary_pos_emb
# Slice the pos emb for current inference
query = apply_rotary_pos_emb(query, q_pos_emb)
key = apply_rotary_pos_emb(key, k_pos_emb)
else:
query_list = []
key_list = []
for i, rotary_pos_emb in enumerate(rotary_pos_emb_list):
rotary_pos_emb = [i[:, -cur_len:, :, :] for i in rotary_pos_emb]
rotary_pos_emb = (rotary_pos_emb,) * 2
q_pos_emb, k_pos_emb = rotary_pos_emb
# Slice the pos emb for current inference
query_list += [apply_rotary_pos_emb(query[i:i+1, :, :], q_pos_emb)]
key_list += [apply_rotary_pos_emb(key[i:i+1, :, :], k_pos_emb)]
query = torch.cat(query_list, dim=0)
key = torch.cat(key_list, dim=0)
if self.use_cache_quantization:
key = quantize_cache_v(key.permute(0, 2, 1, 3),
bits=8,
qmin=self.cache_qmin,
qmax=self.cache_qmax)
value = quantize_cache_v(value.permute(0, 2, 1, 3),
bits=8,
qmin=self.cache_qmin,
qmax=self.cache_qmax)
if layer_past is not None:
past_key, past_value = layer_past[0], layer_past[1]
if self.use_cache_quantization:
# use_cache_quantization:
# present=((q_key,key_scale,key_zero_point),
# (q_value,value_scale,value_zero_point))
key = (torch.cat((past_key[0], key[0]), dim=2),
torch.cat((past_key[1], key[1]), dim=2),
torch.cat((past_key[2], key[2]), dim=2))
value = (torch.cat((past_value[0], value[0]), dim=2),
torch.cat((past_value[1], value[1]), dim=2),
torch.cat((past_value[2], value[2]), dim=2))
else:
# not use_cache_quantization:
# present=(key,value)
key = torch.cat((past_key, key), dim=1)
value = torch.cat((past_value, value), dim=1)
if use_cache:
present = (key, value)
else:
present = None
key_size = key[0].size(2) if self.use_cache_quantization else key.size(1)
if key_size > self.seq_length and self.use_logn_attn and not self.training:
if self.use_cache_quantization:
seq_start = key[0].size(2) - query.size(1)
seq_end = key[0].size(2)
else:
seq_start = key.size(1) - query.size(1)
seq_end = key.size(1)
logn_tensor = self.logn_tensor[:, seq_start:seq_end, :, :].type_as(query)
query = query * logn_tensor.expand_as(query)
2024-01-07 16:22:41 +08:00
key_size = key[0].size(2) if self.use_cache_quantization else key.size(1)
if query.size(1) == key_size:
causal_mask = torch.tril(
torch.ones((key_size, key_size), dtype=torch.bool, device=query.device)
).view(1, 1, key_size, key_size)
2024-01-03 20:26:26 +08:00
else:
2024-01-07 16:22:41 +08:00
causal_mask = None
query = query.permute(0, 2, 1, 3)
if not self.use_cache_quantization:
key = key.permute(0, 2, 1, 3)
value = value.permute(0, 2, 1, 3)
if not self.use_cache_quantization and SUPPORT_TORCH2:
if attention_mask is not None:
attention_mask = attention_mask.expand(
-1, -1, causal_mask.size(2), -1
2024-01-03 20:26:26 +08:00
)
2024-01-07 16:22:41 +08:00
if causal_mask is not None:
attention_mask = attention_mask.masked_fill(~causal_mask, torch.finfo(query.dtype).min)
else:
attention_mask = causal_mask
attn_output = F.scaled_dot_product_attention(
query, key, value, attn_mask=attention_mask
).transpose(1, 2)
attn_weight = None
else:
attn_output, attn_weight = self._attn(
query, key, value, causal_mask, attention_mask, head_mask
)
2024-01-03 20:26:26 +08:00
context_layer = self._merge_heads(
attn_output, self.num_heads, self.head_dim
)
attn_output = self.c_proj(context_layer)
outputs = (attn_output, present)
if output_attentions:
2024-01-07 16:22:41 +08:00
if not self.use_cache_quantization and SUPPORT_TORCH2:
2024-01-03 20:26:26 +08:00
raise ValueError("Cannot output attentions while using scaled_dot_product_attention")
else:
outputs += (attn_weight,)
return outputs
class QWenMLP(nn.Module):
def __init__(self, config):
super().__init__()
self.w1 = nn.Linear(
config.hidden_size, config.intermediate_size // 2, bias=not config.no_bias
)
self.w2 = nn.Linear(
config.hidden_size, config.intermediate_size // 2, bias=not config.no_bias
)
ff_dim_in = config.intermediate_size // 2
self.c_proj = nn.Linear(ff_dim_in, config.hidden_size, bias=not config.no_bias)
def forward(self, hidden_states):
a1 = self.w1(hidden_states)
a2 = self.w2(hidden_states)
intermediate_parallel = a1 * F.silu(a2)
output = self.c_proj(intermediate_parallel)
return output
class QWenBlock(nn.Module):
def __init__(self, config):
super().__init__()
hidden_size = config.hidden_size
self.bf16 = config.bf16
self.ln_1 = RMSNorm(
hidden_size,
eps=config.layer_norm_epsilon,
)
self.attn = QWenAttention(config)
self.ln_2 = RMSNorm(
hidden_size,
eps=config.layer_norm_epsilon,
)
self.mlp = QWenMLP(config)
def forward(
self,
hidden_states: Optional[Tuple[torch.FloatTensor]],
rotary_pos_emb_list: Optional[List[List[torch.Tensor]]] = None,
layer_past: Optional[Tuple[torch.Tensor]] = None,
attention_mask: Optional[torch.FloatTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
encoder_hidden_states: Optional[torch.Tensor] = None,
encoder_attention_mask: Optional[torch.FloatTensor] = None,
use_cache: Optional[bool] = False,
output_attentions: Optional[bool] = False,
):
layernorm_output = self.ln_1(hidden_states)
attn_outputs = self.attn(
layernorm_output,
rotary_pos_emb_list,
layer_past=layer_past,
attention_mask=attention_mask,
head_mask=head_mask,
use_cache=use_cache,
output_attentions=output_attentions,
)
attn_output = attn_outputs[0]
outputs = attn_outputs[1:]
residual = hidden_states
layernorm_input = attn_output + residual
layernorm_output = self.ln_2(layernorm_input)
residual = layernorm_input
mlp_output = self.mlp(layernorm_output)
hidden_states = residual + mlp_output
if use_cache:
outputs = (hidden_states,) + outputs
else:
outputs = (hidden_states,) + outputs[1:]
return outputs
class QWenPreTrainedModel(PreTrainedModel):
config_class = QWenConfig
base_model_prefix = "transformer"
is_parallelizable = False
supports_gradient_checkpointing = True
_no_split_modules = ["QWenBlock"]
_skip_keys_device_placement = "past_key_values"
def __init__(self, *inputs, **kwargs):
super().__init__(*inputs, **kwargs)
def _init_weights(self, module):
"""Initialize the weights."""
if isinstance(module, nn.Linear):
module.weight.data.normal_(mean=0.0, std=self.config.initializer_range)
if module.bias is not None:
module.bias.data.zero_()
elif isinstance(module, nn.Embedding):
module.weight.data.normal_(mean=0.0, std=self.config.initializer_range)
if module.padding_idx is not None:
module.weight.data[module.padding_idx].zero_()
elif isinstance(module, RMSNorm):
module.weight.data.fill_(1.0)
for name, p in module.named_parameters():
if name == "c_proj.weight":
p.data.normal_(
mean=0.0,
std=(
self.config.initializer_range
/ math.sqrt(2 * self.config.num_hidden_layers)
),
)
def _set_gradient_checkpointing(self, module, value=False):
if isinstance(module, QWenModel):
module.gradient_checkpointing = value
class QWenModel(QWenPreTrainedModel):
_keys_to_ignore_on_load_missing = ["attn.masked_bias"]
def __init__(self, config):
super().__init__(config)
self.vocab_size = config.vocab_size
self.num_hidden_layers = config.num_hidden_layers
self.embed_dim = config.hidden_size
self.use_cache_quantization = self.config.use_cache_quantization if hasattr(self.config, 'use_cache_quantization') else False
self.gradient_checkpointing = False
self.use_dynamic_ntk = config.use_dynamic_ntk
self.seq_length = config.seq_length
self.wte = nn.Embedding(self.vocab_size, self.embed_dim)
self.drop = nn.Dropout(config.emb_dropout_prob)
if config.rotary_pct == 1.0:
self.rotary_ndims = None
else:
assert config.rotary_pct < 1
self.rotary_ndims = int(
config.kv_channels * config.rotary_pct
)
dim = (
self.rotary_ndims
if self.rotary_ndims is not None
else config.kv_channels
)
self.rotary_emb = RotaryEmbedding(dim, base=config.rotary_emb_base)
self.is_fp32 = not (config.bf16 or config.fp16)
self.h = nn.ModuleList(
[
QWenBlock(
config
)
for i in range(config.num_hidden_layers)
]
)
self.ln_f = RMSNorm(
self.embed_dim,
eps=config.layer_norm_epsilon,
)
self.post_init()
def get_input_embeddings(self):
return self.wte
def set_input_embeddings(self, new_embeddings):
self.wte = new_embeddings
def get_ntk_alpha(self, true_seq_len):
context_value = math.log(true_seq_len / self.seq_length, 2) + 1
ntk_alpha = 2 ** math.ceil(context_value) - 1
ntk_alpha = max(ntk_alpha, 1)
return ntk_alpha
def forward(
self,
input_ids: Optional[torch.LongTensor] = None,
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
attention_mask: Optional[torch.FloatTensor] = None,
token_type_ids: Optional[torch.LongTensor] = None,
position_ids: Optional[torch.LongTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
inputs_embeds: Optional[torch.FloatTensor] = None,
encoder_hidden_states: Optional[torch.Tensor] = None,
encoder_attention_mask: Optional[torch.FloatTensor] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
):
output_attentions = (
output_attentions
if output_attentions is not None
else self.config.output_attentions
)
output_hidden_states = (
output_hidden_states
if output_hidden_states is not None
else self.config.output_hidden_states
)
use_cache = use_cache if use_cache is not None else self.config.use_cache
return_dict = (
return_dict if return_dict is not None else self.config.use_return_dict
)
if input_ids is not None and inputs_embeds is not None:
raise ValueError(
"You cannot specify both input_ids and inputs_embeds at the same time"
)
elif input_ids is not None:
input_shape = input_ids.size()
input_ids = input_ids.view(-1, input_shape[-1])
batch_size = input_ids.shape[0]
elif inputs_embeds is not None:
input_shape = inputs_embeds.size()[:-1]
batch_size = inputs_embeds.shape[0]
else:
raise ValueError("You have to specify either input_ids or inputs_embeds")
device = input_ids.device if input_ids is not None else inputs_embeds.device
if token_type_ids is not None:
token_type_ids = token_type_ids.view(-1, input_shape[-1])
if position_ids is not None:
position_ids = position_ids.view(-1, input_shape[-1])
if past_key_values is None:
past_length = 0
past_key_values = tuple([None] * len(self.h))
else:
if self.use_cache_quantization:
past_length = past_key_values[0][0][0].size(2)
else:
past_length = past_key_values[0][0].size(-2)
if position_ids is None:
position_ids = torch.arange(
past_length,
input_shape[-1] + past_length,
dtype=torch.long,
device=device,
)
position_ids = position_ids.unsqueeze(0).view(-1, input_shape[-1])
if attention_mask is not None:
if batch_size <= 0:
raise ValueError("batch_size has to be defined and > 0")
attention_mask = attention_mask.view(batch_size, -1)
attention_mask = attention_mask[:, None, None, :]
attention_mask = attention_mask.to(dtype=self.dtype)
attention_mask = (1.0 - attention_mask) * torch.finfo(self.dtype).min
encoder_attention_mask = None
head_mask = self.get_head_mask(head_mask, self.config.num_hidden_layers)
if inputs_embeds is None:
inputs_embeds = self.wte(input_ids)
hidden_states = inputs_embeds
kv_seq_len = hidden_states.size()[1]
if past_key_values[0] is not None:
# past key values[0][0] shape: bs * seq_len * head_num * dim
if self.use_cache_quantization:
kv_seq_len += past_key_values[0][0][0].shape[2]
else:
kv_seq_len += past_key_values[0][0].shape[1]
if self.training or not self.use_dynamic_ntk:
ntk_alpha_list = [1.0]
elif kv_seq_len != hidden_states.size()[1]:
ntk_alpha_list = self.rotary_emb._ntk_alpha_cached_list
else:
ntk_alpha_list = []
if attention_mask is not None and kv_seq_len > self.seq_length:
true_seq_lens = attention_mask.squeeze(1).squeeze(1).eq(0).sum(dim=-1, dtype=torch.int32)
for i in range(hidden_states.size()[0]):
true_seq_len = true_seq_lens[i].item()
ntk_alpha = self.get_ntk_alpha(true_seq_len)
ntk_alpha_list.append(ntk_alpha)
else:
ntk_alpha = self.get_ntk_alpha(kv_seq_len)
ntk_alpha_list.append(ntk_alpha)
self.rotary_emb._ntk_alpha_cached_list = ntk_alpha_list
rotary_pos_emb_list = [
self.rotary_emb(kv_seq_len, ntk_alpha=ntk_alpha) for ntk_alpha in ntk_alpha_list
]
hidden_states = self.drop(hidden_states)
output_shape = input_shape + (hidden_states.size(-1),)
if self.gradient_checkpointing and self.training:
if use_cache:
logger.warning_once(
"`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`..."
)
use_cache = False
presents = () if use_cache else None
all_self_attentions = () if output_attentions else None
all_hidden_states = () if output_hidden_states else None
for i, (block, layer_past) in enumerate(zip(self.h, past_key_values)):
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
if self.gradient_checkpointing and self.training:
def create_custom_forward(module):
def custom_forward(*inputs):
# None for past_key_value
return module(*inputs, use_cache, output_attentions)
return custom_forward
outputs = torch.utils.checkpoint.checkpoint(
create_custom_forward(block),
hidden_states,
rotary_pos_emb_list,
None,
attention_mask,
head_mask[i],
encoder_hidden_states,
encoder_attention_mask,
)
else:
outputs = block(
hidden_states,
layer_past=layer_past,
rotary_pos_emb_list=rotary_pos_emb_list,
attention_mask=attention_mask,
head_mask=head_mask[i],
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_attention_mask,
use_cache=use_cache,
output_attentions=output_attentions,
)
hidden_states = outputs[0]
if use_cache is True:
presents = presents + (outputs[1],)
if output_attentions:
all_self_attentions = all_self_attentions + (outputs[2 if use_cache else 1],)
hidden_states = self.ln_f(hidden_states)
hidden_states = hidden_states.view(output_shape)
# Add last hidden state
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
if not return_dict:
return tuple(
v for v in [hidden_states, presents, all_hidden_states] if v is not None
)
return BaseModelOutputWithPast(
last_hidden_state=hidden_states,
past_key_values=presents,
hidden_states=all_hidden_states,
attentions=all_self_attentions,
)
class QWenLMHeadModel(QWenPreTrainedModel):
_keys_to_ignore_on_load_missing = [r"h\.\d+\.attn\.rotary_emb\.inv_freq"]
_keys_to_ignore_on_load_unexpected = [r"h\.\d+\.attn\.masked_bias"]
def __init__(self, config):
super().__init__(config)
assert (
config.bf16 + config.fp16 + config.fp32 <= 1
), "Only one of \"bf16\", \"fp16\", \"fp32\" can be true"
autoset_precision = config.bf16 + config.fp16 + config.fp32 == 0
if autoset_precision:
if SUPPORT_BF16:
logger.warn(
"The model is automatically converting to bf16 for faster inference. "
"If you want to disable the automatic precision, please manually add bf16/fp16/fp32=True to \"AutoModelForCausalLM.from_pretrained\"."
)
config.bf16 = True
elif SUPPORT_FP16:
logger.warn(
"The model is automatically converting to fp16 for faster inference. "
"If you want to disable the automatic precision, please manually add bf16/fp16/fp32=True to \"AutoModelForCausalLM.from_pretrained\"."
)
config.fp16 = True
else:
config.fp32 = True
if config.bf16 and SUPPORT_CUDA and not SUPPORT_BF16:
logger.warn("Your device does NOT seem to support bf16, you can switch to fp16 or fp32 by by passing fp16/fp32=True in \"AutoModelForCausalLM.from_pretrained\".")
if config.fp16 and SUPPORT_CUDA and not SUPPORT_FP16:
logger.warn("Your device does NOT support faster inference with fp16, please switch to fp32 which is likely to be faster")
if config.fp32:
if SUPPORT_BF16:
logger.warn("Your device support faster inference by passing bf16=True in \"AutoModelForCausalLM.from_pretrained\".")
elif SUPPORT_FP16:
logger.warn("Your device support faster inference by passing fp16=True in \"AutoModelForCausalLM.from_pretrained\".")
self.transformer = QWenModel(config)
self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False)
if config.bf16:
self.transformer.bfloat16()
self.lm_head.bfloat16()
if config.fp16:
self.transformer.half()
self.lm_head.half()
self.post_init()
def get_output_embeddings(self):
return self.lm_head
def set_output_embeddings(self, new_embeddings):
self.lm_head = new_embeddings
def prepare_inputs_for_generation(
self, input_ids, past_key_values=None, inputs_embeds=None, **kwargs
):
if past_key_values:
input_ids = input_ids[:, -1].unsqueeze(-1)
if input_ids.size(0) == 1:
attention_mask = None
else:
attention_mask = kwargs.get("attention_mask", None)
if inputs_embeds is not None and past_key_values is None:
model_inputs = {"inputs_embeds": inputs_embeds}
else:
model_inputs = {"input_ids": input_ids}
model_inputs.update(
{
"past_key_values": past_key_values,
"use_cache": kwargs.get("use_cache"),
"attention_mask": attention_mask,
}
)
return model_inputs
def forward(
self,
input_ids: Optional[torch.LongTensor] = None,
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
attention_mask: Optional[torch.FloatTensor] = None,
token_type_ids: Optional[torch.LongTensor] = None,
position_ids: Optional[torch.LongTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
inputs_embeds: Optional[torch.FloatTensor] = None,
encoder_hidden_states: Optional[torch.Tensor] = None,
encoder_attention_mask: Optional[torch.FloatTensor] = None,
labels: Optional[torch.LongTensor] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
) -> Union[Tuple, CausalLMOutputWithPast]:
return_dict = (
return_dict if return_dict is not None else self.config.use_return_dict
)
transformer_outputs = self.transformer(
input_ids,
past_key_values=past_key_values,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
position_ids=position_ids,
head_mask=head_mask,
inputs_embeds=inputs_embeds,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_attention_mask,
use_cache=use_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
hidden_states = transformer_outputs[0]
lm_logits = self.lm_head(hidden_states)
loss = None
if labels is not None:
labels = labels.to(lm_logits.device)
shift_logits = lm_logits[..., :-1, :].contiguous()
shift_labels = labels[..., 1:].contiguous()
loss_fct = CrossEntropyLoss()
loss = loss_fct(
shift_logits.view(-1, shift_logits.size(-1)), shift_labels.view(-1)
)
# shift_labels = torch.ones([1,19]).to(lm_logits.device).to(torch.int64)
# shift_logits = lm_logits[..., :-1, :].contiguous()
# loss_fct = CrossEntropyLoss()
# loss = loss_fct(
# shift_logits.view(-1, shift_logits.size(-1)), shift_labels.view(-1)
# )
# loss.backward()
2024-01-03 20:26:26 +08:00
if not return_dict:
output = (lm_logits,) + transformer_outputs[1:]
return ((loss,) + output) if loss is not None else output
return CausalLMOutputWithPast(
loss=loss,
logits=lm_logits,
past_key_values=transformer_outputs.past_key_values,
hidden_states=transformer_outputs.hidden_states,
attentions=transformer_outputs.attentions,
)
@staticmethod
def _reorder_cache(
past_key_values: Tuple[Tuple[torch.Tensor]], beam_idx: torch.Tensor
) -> Tuple[Tuple[torch.Tensor]]:
return tuple(
tuple(
past_state.index_select(0, beam_idx.to(past_state.device))
for past_state in layer_past
)
for layer_past in past_key_values
)
def chat(
self,
tokenizer: PreTrainedTokenizer,
query: str,
history: Optional[HistoryType],
system: str = "You are a helpful assistant.",
stream: Optional[bool] = _SENTINEL,
stop_words_ids: Optional[List[List[int]]] = None,
generation_config: Optional[GenerationConfig] = None,
**kwargs,
) -> Tuple[str, HistoryType]:
generation_config = generation_config if generation_config is not None else self.generation_config
assert stream is _SENTINEL, _ERROR_STREAM_IN_CHAT
assert generation_config.chat_format == 'chatml', _ERROR_BAD_CHAT_FORMAT
if history is None:
history = []
else:
# make a copy of the user's input such that is is left untouched
history = copy.deepcopy(history)
if stop_words_ids is None:
stop_words_ids = []
max_window_size = kwargs.get('max_window_size', None)
if max_window_size is None:
max_window_size = generation_config.max_window_size
raw_text, context_tokens = make_context(
tokenizer,
query,
history=history,
system=system,
max_window_size=max_window_size,
chat_format=generation_config.chat_format,
)
stop_words_ids.extend(get_stop_words_ids(
generation_config.chat_format, tokenizer
))
input_ids = torch.tensor([context_tokens]).to(self.device)
outputs = self.generate(
input_ids,
stop_words_ids=stop_words_ids,
return_dict_in_generate=False,
generation_config=generation_config,
**kwargs,
)
2024-01-03 20:26:26 +08:00
response = decode_tokens(
outputs[0],
tokenizer,
raw_text_len=len(raw_text),
context_length=len(context_tokens),
chat_format=generation_config.chat_format,
verbose=False,
errors='replace'
)
# as history is a copy of the user inputs,
# we can always return the new turn to the user.
# separating input history and output history also enables the user
# to implement more complex history management
history.append((query, response))
return response, history
def chat_stream(
self,
tokenizer: PreTrainedTokenizer,
query: str,
history: Optional[HistoryType],
system: str = "You are a helpful assistant.",
stop_words_ids: Optional[List[List[int]]] = None,
logits_processor: Optional[LogitsProcessorList] = None,
generation_config: Optional[GenerationConfig] = None,
**kwargs,
) -> Generator[str, Any, None]:
generation_config = generation_config if generation_config is not None else self.generation_config
assert generation_config.chat_format == 'chatml', _ERROR_BAD_CHAT_FORMAT
if history is None:
history = []
if stop_words_ids is None:
stop_words_ids = []
max_window_size = kwargs.get('max_window_size', None)
if max_window_size is None:
max_window_size = generation_config.max_window_size
raw_text, context_tokens = make_context(
tokenizer,
query,
history=history,
system=system,
max_window_size=max_window_size,
chat_format=generation_config.chat_format,
)
stop_words_ids.extend(get_stop_words_ids(
generation_config.chat_format, tokenizer
))
if stop_words_ids is not None:
stop_words_logits_processor = StopWordsLogitsProcessor(
stop_words_ids=stop_words_ids,
eos_token_id=generation_config.eos_token_id,
)
if logits_processor is None:
logits_processor = LogitsProcessorList([stop_words_logits_processor])
else:
logits_processor.append(stop_words_logits_processor)
input_ids = torch.tensor([context_tokens]).to(self.device)
from transformers_stream_generator.main import NewGenerationMixin, StreamGenerationConfig
self.__class__.generate_stream = NewGenerationMixin.generate
self.__class__.sample_stream = NewGenerationMixin.sample_stream
stream_config = StreamGenerationConfig(**generation_config.to_dict(), do_stream=True)
def stream_generator():
outputs = []
for token in self.generate_stream(
input_ids,
return_dict_in_generate=False,
generation_config=stream_config,
logits_processor=logits_processor,
seed=-1,
**kwargs):
outputs.append(token.item())
yield tokenizer.decode(outputs, skip_special_tokens=True, errors='ignore')
return stream_generator()
def generate(
self,
inputs: Optional[torch.Tensor] = None,
generation_config: Optional[GenerationConfig] = None,
logits_processor: Optional[LogitsProcessorList] = None,
stopping_criteria: Optional[StoppingCriteriaList] = None,
prefix_allowed_tokens_fn: Optional[
Callable[[int, torch.Tensor], List[int]]
] = None,
synced_gpus: Optional[bool] = None,
assistant_model: Optional["PreTrainedModel"] = None,
streamer: Optional["BaseStreamer"] = None,
**kwargs,
) -> Union[GenerateOutput, torch.LongTensor]:
generation_config = generation_config if generation_config is not None else self.generation_config
# Process stop_words_ids.
stop_words_ids = kwargs.pop("stop_words_ids", None)
if stop_words_ids is None and generation_config is not None:
stop_words_ids = getattr(generation_config, "stop_words_ids", None)
if stop_words_ids is None:
stop_words_ids = getattr(generation_config, "stop_words_ids", None)
if stop_words_ids is not None:
stop_words_logits_processor = StopWordsLogitsProcessor(
stop_words_ids=stop_words_ids,
eos_token_id=generation_config.eos_token_id,
)
if logits_processor is None:
logits_processor = LogitsProcessorList([stop_words_logits_processor])
else:
logits_processor.append(stop_words_logits_processor)
return self.generate_base(
2024-01-03 20:26:26 +08:00
inputs,
generation_config=generation_config,
logits_processor=logits_processor,
stopping_criteria=stopping_criteria,
prefix_allowed_tokens_fn=prefix_allowed_tokens_fn,
synced_gpus=synced_gpus,
assistant_model=assistant_model,
streamer=streamer,
**kwargs,
)
def generate_base(
self,
inputs: Optional[torch.Tensor] = None,
generation_config: Optional[GenerationConfig] = None,
logits_processor: Optional[LogitsProcessorList] = None,
stopping_criteria: Optional[StoppingCriteriaList] = None,
prefix_allowed_tokens_fn: Optional[Callable[[int, torch.Tensor], List[int]]] = None,
synced_gpus: Optional[bool] = None,
assistant_model: Optional["PreTrainedModel"] = None,
streamer: Optional["BaseStreamer"] = None,
negative_prompt_ids: Optional[torch.Tensor] = None,
negative_prompt_attention_mask: Optional[torch.Tensor] = None,
**kwargs,
) -> Union[GenerateOutput, torch.LongTensor]:
if synced_gpus is None:
synced_gpus = False
# 1. Handle `generation_config` and kwargs that might update it, and validate the `.generate()` call
self._validate_model_class()
# priority: `generation_config` argument > `model.generation_config` (the default generation config)
if generation_config is None:
# legacy: users may modify the model configuration to control generation. To trigger this legacy behavior,
# two conditions must be met
# 1) the generation config must have been created from the model config (`_from_model_config` field);
# 2) the generation config must have seen no modification since its creation (the hash is the same).
if self.generation_config._from_model_config and self.generation_config._original_object_hash == hash(
self.generation_config
):
new_generation_config = GenerationConfig.from_model_config(self.config)
if new_generation_config != self.generation_config:
warnings.warn(
"You have modified the pretrained model configuration to control generation. This is a"
" deprecated strategy to control generation and will be removed soon, in a future version."
" Please use and modify the model generation configuration (see"
" https://huggingface.co/docs/transformers/generation_strategies#default-text-generation-configuration )"
)
self.generation_config = new_generation_config
generation_config = self.generation_config
generation_config = copy.deepcopy(generation_config)
model_kwargs = generation_config.update(**kwargs) # All unused kwargs must be model kwargs
generation_config.validate()
self._validate_model_kwargs(model_kwargs.copy())
# 2. Set generation parameters if not already defined
logits_processor = logits_processor if logits_processor is not None else LogitsProcessorList()
stopping_criteria = stopping_criteria if stopping_criteria is not None else StoppingCriteriaList()
if generation_config.pad_token_id is None and generation_config.eos_token_id is not None:
if model_kwargs.get("attention_mask", None) is None:
logger.warning(
"The attention mask and the pad token id were not set. As a consequence, you may observe "
"unexpected behavior. Please pass your input's `attention_mask` to obtain reliable results."
)
eos_token_id = generation_config.eos_token_id
if isinstance(eos_token_id, list):
eos_token_id = eos_token_id[0]
logger.warning(f"Setting `pad_token_id` to `eos_token_id`:{eos_token_id} for open-end generation.")
generation_config.pad_token_id = eos_token_id
# 3. Define model inputs
# inputs_tensor has to be defined
# model_input_name is defined if model-specific keyword input is passed
# otherwise model_input_name is None
# all model-specific keyword inputs are removed from `model_kwargs`
inputs_tensor, model_input_name, model_kwargs = self._prepare_model_inputs(
inputs, generation_config.bos_token_id, model_kwargs
)
batch_size = inputs_tensor.shape[0]
# 4. Define other model kwargs
model_kwargs["output_attentions"] = generation_config.output_attentions
model_kwargs["output_hidden_states"] = generation_config.output_hidden_states
# decoder-only models with inputs_embeds forwarding must use caching (otherwise we can't detect whether we are
# generating the first new token or not, and we only want to use the embeddings for the first new token)
if not self.config.is_encoder_decoder and model_input_name == "inputs_embeds":
model_kwargs["use_cache"] = True
else:
model_kwargs["use_cache"] = generation_config.use_cache
accepts_attention_mask = "attention_mask" in set(inspect.signature(self.forward).parameters.keys())
requires_attention_mask = "encoder_outputs" not in model_kwargs
if model_kwargs.get("attention_mask", None) is None and requires_attention_mask and accepts_attention_mask:
model_kwargs["attention_mask"] = self._prepare_attention_mask_for_generation(
inputs_tensor, generation_config.pad_token_id, generation_config.eos_token_id
)
# decoder-only models should use left-padding for generation
if not self.config.is_encoder_decoder:
# If `input_ids` was given, check if the last id in any sequence is `pad_token_id`
# Note: If using, `inputs_embeds` this check does not work, because we want to be more hands-off.
if (
generation_config.pad_token_id is not None
and len(inputs_tensor.shape) == 2
and torch.sum(inputs_tensor[:, -1] == generation_config.pad_token_id) > 0
):
logger.warning(
"A decoder-only architecture is being used, but right-padding was detected! For correct "
"generation results, please set `padding_side='left'` when initializing the tokenizer."
)
if self.config.is_encoder_decoder and "encoder_outputs" not in model_kwargs:
# if model is encoder decoder encoder_outputs are created
# and added to `model_kwargs`
model_kwargs = self._prepare_encoder_decoder_kwargs_for_generation(
inputs_tensor, model_kwargs, model_input_name
)
# 5. Prepare `input_ids` which will be used for auto-regressive generation
if self.config.is_encoder_decoder:
input_ids, model_kwargs = self._prepare_decoder_input_ids_for_generation(
batch_size=batch_size,
model_input_name=model_input_name,
model_kwargs=model_kwargs,
decoder_start_token_id=generation_config.decoder_start_token_id,
bos_token_id=generation_config.bos_token_id,
device=inputs_tensor.device,
)
else:
input_ids = inputs_tensor if model_input_name == "input_ids" else model_kwargs.pop("input_ids")
if streamer is not None:
streamer.put(input_ids.cpu())
# 6. Prepare `max_length` depending on other stopping criteria.
input_ids_length = input_ids.shape[-1]
has_default_max_length = kwargs.get("max_length") is None and generation_config.max_length is not None
if generation_config.max_new_tokens is not None:
if not has_default_max_length and generation_config.max_length is not None:
logger.warning(
f"Both `max_new_tokens` (={generation_config.max_new_tokens}) and `max_length`(="
f"{generation_config.max_length}) seem to have been set. `max_new_tokens` will take precedence. "
"Please refer to the documentation for more information. "
"(https://huggingface.co/docs/transformers/main/en/main_classes/text_generation)"
)
generation_config.max_length = generation_config.max_new_tokens + input_ids_length
self._validate_generated_length(generation_config, input_ids_length, has_default_max_length)
# 7. determine generation mode
generation_mode = self._get_generation_mode(generation_config, assistant_model)
if streamer is not None and (generation_config.num_beams > 1):
raise ValueError(
"`streamer` cannot be used with beam search (yet!). Make sure that `num_beams` is set to 1."
)
if self.device.type != input_ids.device.type:
warnings.warn(
"You are calling .generate() with the `input_ids` being on a device type different"
f" than your model's device. `input_ids` is on {input_ids.device.type}, whereas the model"
f" is on {self.device.type}. You may experience unexpected behaviors or slower generation."
" Please make sure that you have put `input_ids` to the"
f" correct device by calling for example input_ids = input_ids.to('{self.device.type}') before"
" running `.generate()`.",
UserWarning,
)
# 8. prepare distribution pre_processing samplers
logits_processor = self._get_logits_processor(
generation_config=generation_config,
input_ids_seq_length=input_ids_length,
encoder_input_ids=inputs_tensor,
prefix_allowed_tokens_fn=prefix_allowed_tokens_fn,
logits_processor=logits_processor,
model_kwargs=model_kwargs,
negative_prompt_ids=negative_prompt_ids,
negative_prompt_attention_mask=negative_prompt_attention_mask,
)
# 9. prepare stopping criteria
stopping_criteria = self._get_stopping_criteria(
generation_config=generation_config, stopping_criteria=stopping_criteria
)
# 10. go into different generation modes
# 11. prepare logits warper
logits_warper = self._get_logits_warper(generation_config)
# 12. expand input_ids with `num_return_sequences` additional sequences per batch
input_ids, model_kwargs = self._expand_inputs_for_generation(
input_ids=input_ids,
expand_size=generation_config.num_return_sequences,
is_encoder_decoder=self.config.is_encoder_decoder,
**model_kwargs,
)
# 13. run sample
return self.sample_base(
input_ids,
logits_processor=logits_processor,
logits_warper=logits_warper,
stopping_criteria=stopping_criteria,
pad_token_id=generation_config.pad_token_id,
eos_token_id=generation_config.eos_token_id,
output_scores=generation_config.output_scores,
return_dict_in_generate=generation_config.return_dict_in_generate,
synced_gpus=synced_gpus,
streamer=streamer,
**model_kwargs,
)
def sample_base(
self,
input_ids: torch.LongTensor,
logits_processor: Optional[LogitsProcessorList] = None,
stopping_criteria: Optional[StoppingCriteriaList] = None,
logits_warper: Optional[LogitsProcessorList] = None,
max_length: Optional[int] = None,
pad_token_id: Optional[int] = None,
eos_token_id: Optional[Union[int, List[int]]] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
output_scores: Optional[bool] = None,
return_dict_in_generate: Optional[bool] = None,
synced_gpus: bool = False,
streamer: Optional["BaseStreamer"] = None,
**model_kwargs,
):
# init values
logits_processor = logits_processor if logits_processor is not None else LogitsProcessorList()
stopping_criteria = stopping_criteria if stopping_criteria is not None else StoppingCriteriaList()
# if max_length is not None:
# warnings.warn(
# "`max_length` is deprecated in this function, use"
# " `stopping_criteria=StoppingCriteriaList([MaxLengthCriteria(max_length=max_length)])` instead.",
# UserWarning,
# )
# stopping_criteria = validate_stopping_criteria(stopping_criteria, max_length)
logits_warper = logits_warper if logits_warper is not None else LogitsProcessorList()
pad_token_id = pad_token_id if pad_token_id is not None else self.generation_config.pad_token_id
eos_token_id = eos_token_id if eos_token_id is not None else self.generation_config.eos_token_id
if isinstance(eos_token_id, int):
eos_token_id = [eos_token_id]
eos_token_id_tensor = torch.tensor(eos_token_id).to(input_ids.device) if eos_token_id is not None else None
output_scores = output_scores if output_scores is not None else self.generation_config.output_scores
output_attentions = (
output_attentions if output_attentions is not None else self.generation_config.output_attentions
)
output_hidden_states = (
output_hidden_states if output_hidden_states is not None else self.generation_config.output_hidden_states
)
return_dict_in_generate = (
return_dict_in_generate
if return_dict_in_generate is not None
else self.generation_config.return_dict_in_generate
)
# init attention / hidden states / scores tuples
scores = () if (return_dict_in_generate and output_scores) else None
decoder_attentions = () if (return_dict_in_generate and output_attentions) else None
cross_attentions = () if (return_dict_in_generate and output_attentions) else None
decoder_hidden_states = () if (return_dict_in_generate and output_hidden_states) else None
# if model is an encoder-decoder, retrieve encoder attention weights and hidden states
if return_dict_in_generate and self.config.is_encoder_decoder:
encoder_attentions = model_kwargs["encoder_outputs"].get("attentions") if output_attentions else None
encoder_hidden_states = (
model_kwargs["encoder_outputs"].get("hidden_states") if output_hidden_states else None
)
# keep track of which sequences are already finished
unfinished_sequences = torch.ones(input_ids.shape[0], dtype=torch.long, device=input_ids.device)
this_peer_finished = False # used by synced_gpus only
# auto-regressive generation
while True:
# if synced_gpus:
# # Under synced_gpus the `forward` call must continue until all gpus complete their sequence.
# # The following logic allows an early break if all peers finished generating their sequence
# this_peer_finished_flag = torch.tensor(0.0 if this_peer_finished else 1.0).to(input_ids.device)
# # send 0.0 if we finished, 1.0 otherwise
# dist.all_reduce(this_peer_finished_flag, op=dist.ReduceOp.SUM)
# # did all peers finish? the reduced sum will be 0.0 then
# if this_peer_finished_flag.item() == 0.0:
# break
# prepare model inputs
model_inputs = self.prepare_inputs_for_generation(input_ids, **model_kwargs)
# forward pass to get next token
outputs = self(
**model_inputs,
return_dict=True,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
if synced_gpus and this_peer_finished:
continue # don't waste resources running the code we don't need
next_token_logits = outputs.logits[:, -1, :]
# pre-process distribution
next_token_scores = logits_processor(input_ids, next_token_logits)
next_token_scores = logits_warper(input_ids, next_token_scores)
# Store scores, attentions and hidden_states when required
if return_dict_in_generate:
if output_scores:
scores += (next_token_scores,)
if output_attentions:
decoder_attentions += (
(outputs.decoder_attentions,) if self.config.is_encoder_decoder else (outputs.attentions,)
)
if self.config.is_encoder_decoder:
cross_attentions += (outputs.cross_attentions,)
if output_hidden_states:
decoder_hidden_states += (
(outputs.decoder_hidden_states,)
if self.config.is_encoder_decoder
else (outputs.hidden_states,)
)
# sample
probs = nn.functional.softmax(next_token_scores, dim=-1)
next_tokens = torch.multinomial(probs, num_samples=1).squeeze(1)
# finished sentences should have their next token be a padding token
if eos_token_id is not None:
if pad_token_id is None:
raise ValueError("If `eos_token_id` is defined, make sure that `pad_token_id` is defined.")
next_tokens = next_tokens * unfinished_sequences + pad_token_id * (1 - unfinished_sequences)
# update generated ids, model inputs, and length for next step
input_ids = torch.cat([input_ids, next_tokens[:, None]], dim=-1)
if streamer is not None:
streamer.put(next_tokens.cpu())
model_kwargs = self._update_model_kwargs_for_generation(
outputs, model_kwargs, is_encoder_decoder=self.config.is_encoder_decoder
)
# if eos_token was found in one sentence, set sentence to finished
if eos_token_id_tensor is not None:
unfinished_sequences = unfinished_sequences.mul(
next_tokens.tile(eos_token_id_tensor.shape[0], 1).ne(eos_token_id_tensor.unsqueeze(1)).prod(dim=0)
)
# stop when each sentence is finished
if unfinished_sequences.max() == 0:
this_peer_finished = True
# stop if we exceed the maximum length
if stopping_criteria(input_ids, scores):
this_peer_finished = True
if this_peer_finished and not synced_gpus:
break
if streamer is not None:
streamer.end()
return input_ids
# def backward(
# self,
# tokenizer,
# query: str,
# ):
# inputs = tokenizer.build_chat_input(query, history=[], role="user")
# inputs = inputs.to(next(self.parameters()).device)
# generation_config = copy.deepcopy(self.generation_config)
# inputs_tensor = inputs["input_ids"]
# input_ids = inputs_tensor.repeat_interleave(
# generation_config.num_return_sequences, dim=0
# )
# input_ids_in = input_ids
# batch_size, seq_length = input_ids_in.shape
# position_ids_in = (
# torch.arange(seq_length, dtype=torch.long, device=input_ids.device)
# .unsqueeze(0)
# .repeat(batch_size, 1)
# )
# model_inputs = {"input_ids": input_ids_in, "position_ids": position_ids_in}
# probs, next_tokens = self.transformer(
# **model_inputs,
# output_hidden_states=None,
# tokenizer=tokenizer,
# )
# next_tokens = torch.multinomial(probs, num_samples=1).squeeze(1)
# # probs_target = probs
# # probs_target[0, next_tokens] = probs_target[0, next_tokens] * 1.1
# loss = probs[0, next_tokens]
# loss.backward()
# return loss
2024-01-03 20:26:26 +08:00
class RotaryEmbedding(torch.nn.Module):
def __init__(self, dim, base=10000):
super().__init__()
self.dim = dim
self.base = base
inv_freq = 1.0 / (base ** (torch.arange(0, dim, 2).float() / dim))
self.register_buffer("inv_freq", inv_freq, persistent=False)
if importlib.util.find_spec("einops") is None:
raise RuntimeError("einops is required for Rotary Embedding")
self._rotary_pos_emb_cache = None
self._seq_len_cached = 0
self._ntk_alpha_cached = 1.0
self._ntk_alpha_cached_list = [1.0]
def update_rotary_pos_emb_cache(self, seqlen, ntk_alpha=1.0):
if seqlen > self._seq_len_cached or ntk_alpha != self._ntk_alpha_cached:
base = self.base * ntk_alpha ** (self.dim / (self.dim - 2))
self.inv_freq = 1.0 / (
base
** (
torch.arange(0, self.dim, 2, device=self.inv_freq.device).float()
/ self.dim
)
)
self._seq_len_cached = max(2 * seqlen, 16)
self._ntk_alpha_cached = ntk_alpha
seq = torch.arange(self._seq_len_cached, device=self.inv_freq.device)
freqs = torch.outer(seq.type_as(self.inv_freq), self.inv_freq)
emb = torch.cat((freqs, freqs), dim=-1)
from einops import rearrange
emb = rearrange(emb, "n d -> 1 n 1 d")
cos, sin = emb.cos(), emb.sin()
self._rotary_pos_emb_cache = [cos, sin]
def forward(self, max_seq_len, ntk_alpha=1.0):
self.update_rotary_pos_emb_cache(max_seq_len, ntk_alpha)
cos, sin = self._rotary_pos_emb_cache
return [cos[:, :max_seq_len], sin[:, :max_seq_len]]
def _rotate_half(x):
from einops import rearrange
x = rearrange(x, "... (j d) -> ... j d", j=2)
x1, x2 = x.unbind(dim=-2)
return torch.cat((-x2, x1), dim=-1)
def apply_rotary_pos_emb(t, freqs):
""" Apply rotary embedding to the first rotary_dim of the iput
Arguments:
t (tensor(batch_size, seq_len, n_head, head_dim)):
the input embedding/hidden states
freqs (list[tensor(1, seq_len, 1, rotary_dim), tensor(1, seq_len, 1, rotary_dim)]):
2024-01-03 21:03:27 +08:00
the cached cos/sin position embeddings
2024-01-03 20:26:26 +08:00
"""
rot_dim = freqs[0].shape[-1]
cos, sin = freqs
t_float = t.float()
if apply_rotary_emb_func is not None and t.is_cuda:
2024-01-03 21:03:27 +08:00
# apply_rotary_emb in flash_attn requires cos/sin to be of
# shape (seqlen, rotary_dim / 2) and apply rotary embedding
2024-01-03 20:26:26 +08:00
# to the first rotary_dim of the input
cos = cos.squeeze(0).squeeze(1)[:, : rot_dim // 2]
sin = sin.squeeze(0).squeeze(1)[:, : rot_dim // 2]
return apply_rotary_emb_func(t_float, cos, sin).type_as(t)
else:
t_rot, t_pass = t_float[..., :rot_dim], t_float[..., rot_dim:]
t_rot = (t_rot * cos) + (_rotate_half(t_rot) * sin)
return torch.cat((t_rot, t_pass), dim=-1).type_as(t)
class RMSNorm(torch.nn.Module):
def __init__(self, dim: int, eps: float = 1e-6):
super().__init__()
self.eps = eps
self.weight = nn.Parameter(torch.ones(dim))
def _norm(self, x):
return x * torch.rsqrt(x.pow(2).mean(-1, keepdim=True) + self.eps)
def forward(self, x):
if rms_norm is not None and x.is_cuda:
return rms_norm(x, self.weight, self.eps)
else:
output = self._norm(x.float()).type_as(x)
2024-01-03 21:03:27 +08:00
return output * self.weight