unsloth/unsloth/models/mistral.py
Daniel Han-Chen 270df81b60 Remove fast path
2024-01-30 17:33:08 +11:00

390 lines
15 KiB
Python

# Copyright 2023-present Daniel Han-Chen & the Unsloth team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from .llama import *
from ._utils import __version__
from transformers.models.mistral.modeling_mistral import (
MistralAttention,
MistralDecoderLayer,
MistralModel,
MistralForCausalLM,
)
# For Pytorch 2.1.1
try:
from transformers.models.mistral.modeling_mistral import (
MistralSdpaAttention,
MistralFlashAttention2,
)
except:
MistralSdpaAttention = MistralAttention
MistralFlashAttention2 = MistralAttention
pass
def MistralAttention_fast_forward(
self,
hidden_states: torch.Tensor,
causal_mask: Optional[xformers.attn_bias.BlockDiagonalCausalMask] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_value: Optional[Tuple[torch.Tensor]] = None,
output_attentions: bool = False,
use_cache: bool = False,
padding_mask: Optional[torch.LongTensor] = None,
*args, **kwargs,
) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
bsz, q_len, _ = hidden_states.size()
# Check for inference
if False:
A, past_key_value = LlamaAttention_fast_forward_inference(
self,
hidden_states,
past_key_value,
position_ids,
)
return A, None, past_key_value
pass
n_heads = self.num_heads
n_groups = self.num_key_value_groups
n_kv_heads = self.num_key_value_heads
head_dim = self.head_dim
assert(n_kv_heads * n_groups == n_heads)
Q, K, V = self.apply_qkv(self, hidden_states)
Q = Q.view(bsz, q_len, n_heads, head_dim).transpose(1, 2)
K = K.view(bsz, q_len, n_kv_heads, head_dim).transpose(1, 2)
V = V.view(bsz, q_len, n_kv_heads, head_dim).transpose(1, 2)
kv_seq_len = K.shape[-2]
if past_key_value is not None:
kv_seq_len += past_key_value[0].shape[-2]
if position_ids is None:
cos = self.rotary_emb.cos_cached
sin = self.rotary_emb.sin_cached
Q, K = fast_rope_embedding(Q, K, cos, sin)
else:
cos, sin = self.rotary_emb(V, seq_len = kv_seq_len)
Q, K = inplace_rope_embedding(Q, K, cos, sin, position_ids)
pass
if past_key_value is not None:
K = torch.cat([past_key_value[0], K], dim = 2)
V = torch.cat([past_key_value[1], V], dim = 2)
pass
past_key_value = (K, V) if use_cache else None
# Attention module
if (not HAS_FLASH_ATTENTION):
# Xformers memory efficient attention
Q = Q.transpose(1, 2)
K = K.transpose(1, 2)
V = V.transpose(1, 2)
K_M = V_M = bsz * kv_seq_len
Q_M = bsz * q_len
has_swa = isinstance(causal_mask, xformers.attn_bias.BlockDiagonalCausalMask)
# Group query attention
K = K .view(bsz, kv_seq_len, n_kv_heads, 1, head_dim)
V = V .view(bsz, kv_seq_len, n_kv_heads, 1, head_dim)
K = K.expand(bsz, kv_seq_len, n_kv_heads, n_groups, head_dim)
V = V.expand(bsz, kv_seq_len, n_kv_heads, n_groups, head_dim)
if hidden_states.requires_grad:
K = K.reshape(bsz, kv_seq_len, n_heads, head_dim)
V = V.reshape(bsz, kv_seq_len, n_heads, head_dim)
if has_swa:
Q = Q.view(1, Q_M, n_heads, head_dim)
K = K.view(1, K_M, n_heads, head_dim)
V = V.view(1, V_M, n_heads, head_dim)
pass
else:
# Xformers does support the forward pass though
Q = Q.view(bsz, q_len, n_kv_heads, n_groups, head_dim)
if has_swa:
Q = Q.view(1, Q_M, n_kv_heads, n_groups, head_dim)
K = K.view(1, K_M, n_kv_heads, n_groups, head_dim)
V = V.view(1, V_M, n_kv_heads, n_groups, head_dim)
pass
pass
A = xformers_attention(Q, K, V, attn_bias = causal_mask)
A = A.view(bsz, q_len, n_heads, head_dim)
elif HAS_FLASH_ATTENTION:
Q = Q.transpose(1, 2)
K = K.transpose(1, 2)
V = V.transpose(1, 2)
sw = getattr(self.config, "sliding_window", None)
sw = kv_seq_len if (sw is None or sw == "null") else sw
window = (-1, -1) if (kv_seq_len <= sw) else (sw, sw)
A = flash_attn_func(Q, K, V, causal = True, window_size = window)
else:
# Grouped query attention
# if n_groups != 1:
K = K[:, :, None, :, :].expand(bsz, n_kv_heads, n_groups, kv_seq_len, head_dim)
V = V[:, :, None, :, :].expand(bsz, n_kv_heads, n_groups, kv_seq_len, head_dim)
K = K.reshape(bsz, n_heads, kv_seq_len, head_dim)
V = V.reshape(bsz, n_heads, kv_seq_len, head_dim)
# pass
# Needs (batch_size, n_heads, seq_len, head_dim)
# is_casual and attention_mask must not be both set!
A = scaled_dot_product_attention(Q, K, V, attn_mask = attention_mask, is_causal = False)
# Go back to (batch_size, seq_len, n_heads, head_dim)
A = A.transpose(1, 2)
pass
attn_output = A.reshape(bsz, q_len, self.hidden_size)
attn_output = self.apply_o(self, attn_output)
attn_weights = None
return attn_output, attn_weights, past_key_value
pass
def MistralForCausalLM_fast_forward(
self,
input_ids: torch.LongTensor = None,
causal_mask: Optional[xformers.attn_bias.BlockDiagonalCausalMask] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_values: Optional[List[torch.FloatTensor]] = None,
inputs_embeds: 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,
*args, **kwargs,
) -> Union[Tuple, CausalLMOutputWithPast]:
if causal_mask is None:
bsz, q_len = input_ids.shape
sliding_window = getattr(self.config, "sliding_window", None)
if sliding_window is None or sliding_window == "null" or sliding_window <= 0:
causal_mask = xformers.attn_bias.LowerTriangularMask()
elif q_len <= sliding_window:
causal_mask = xformers.attn_bias.LowerTriangularMask()
else:
# Fix from https://github.com/Rypo
causal_mask = xformers.attn_bias.BlockDiagonalCausalMask\
.from_seqlens([q_len]*bsz)\
.make_local_attention(window_size = sliding_window)
pass
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
)
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
# decoder outputs consists of (dec_features, layer_state, dec_hidden, dec_attn)
self.model._has_no_labels = labels is None
outputs = self.model(
input_ids=input_ids,
causal_mask=causal_mask,
attention_mask=attention_mask,
position_ids=position_ids,
past_key_values=past_key_values,
inputs_embeds=inputs_embeds,
use_cache=use_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
hidden_states = outputs[0]
# bsz, q_len, hd = hidden_states.shape
# if bsz == 1 and q_len == 1:
# logits = torch.mv(self.lm_head.weight, hidden_states.ravel())
# logits = logits.unsqueeze(0).unsqueeze(0)
# else:
logits = self.lm_head(hidden_states)
pass
loss = None
if labels is not None:
shift_logits = logits
if not hasattr(self, "extra_ignored_labels"):
# Fixes https://github.com/unslothai/unsloth/issues/10
self.extra_ignored_labels = torch.full((self.max_seq_length, 1), -100, device = "cuda")
pass
shift_labels = torch.hstack((labels[..., 1:], self.extra_ignored_labels[:labels.shape[0]]))
loss = fast_cross_entropy_loss(
logits = shift_logits,
labels = shift_labels,
)
pass
if not return_dict:
output = (logits,) + outputs[1:]
return (loss,) + output if loss is not None else output
return CausalLMOutputWithPast(
loss=loss,
logits=logits,
past_key_values=outputs.past_key_values,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
pass
class FastMistralModel(FastLlamaModel):
@staticmethod
def pre_patch():
MistralAttention .forward = MistralAttention_fast_forward
MistralSdpaAttention .forward = MistralAttention_fast_forward
MistralFlashAttention2.forward = MistralAttention_fast_forward
MistralDecoderLayer .forward = LlamaDecoderLayer_fast_forward
MistralModel .forward = LlamaModel_fast_forward
MistralForCausalLM .forward = MistralForCausalLM_fast_forward
PeftModelForCausalLM .forward = PeftModelForCausalLM_fast_forward
return
pass
@staticmethod
def from_pretrained(
model_name = "unsloth/mistral-7b-bnb-4bit",
max_seq_length = 4096,
dtype = None,
load_in_4bit = True,
token = None,
device_map = "sequential",
rope_scaling = None, # Mistral does not support RoPE scaling
fix_tokenizer = True,
**kwargs,
):
# Mistral does NOT support RoPE Scaling!
if rope_scaling is not None:
logger.warning_once("Unsloth: Mistral models do not support RoPE scaling.")
pass
SUPPORTS_BFLOAT16 = torch.cuda.is_bf16_supported()
gpu_stats = torch.cuda.get_device_properties(0)
max_memory = round(gpu_stats.total_memory / 1024 / 1024 / 1024, 3)
statistics = \
f"==((====))== Unsloth: Fast Mistral patching release {__version__}\n"\
f" \\\ /| GPU: {gpu_stats.name}. Max memory: {max_memory} GB. Platform = {platform_system}.\n"\
f"O^O/ \_/ \\ Pytorch: {torch.__version__}. CUDA = {gpu_stats.major}.{gpu_stats.minor}. CUDA Toolkit = {torch.version.cuda}.\n"\
f"\ / Bfloat16 = {str(SUPPORTS_BFLOAT16).upper()}. Xformers = {xformers_version}. FA = {HAS_FLASH_ATTENTION}.\n"\
f' "-____-" Apache 2 free license: http://github.com/unslothai/unsloth'
print(statistics)
FastMistralModel.pre_patch()
if dtype is None:
dtype = torch.float16 if not SUPPORTS_BFLOAT16 else torch.bfloat16
elif dtype == torch.bfloat16 and not SUPPORTS_BFLOAT16:
logger.warning_once("Device does not support bfloat16. Will change to float16.")
dtype = torch.float16
assert(dtype == torch.float16 or dtype == torch.bfloat16 or dtype == torch.float32)
# Check max sequence length
model_config = AutoConfig.from_pretrained(model_name, token = token)
model_max_seq_length = model_config.max_position_embeddings
# Mistral does NOT support RoPE Scaling sadly so we have to error out.
if max_seq_length > model_max_seq_length:
raise RuntimeError(
"Unsloth: Unfortunately Mistral type models do not support RoPE scaling!\n"\
f"The maximum sequence length supported is {model_max_seq_length}.",
)
pass
bnb_config = None
if load_in_4bit:
bnb_config = BitsAndBytesConfig(
load_in_4bit = True,
bnb_4bit_use_double_quant = True,
bnb_4bit_quant_type = "nf4",
bnb_4bit_compute_dtype = dtype,
)
max_position_embeddings = max(max_seq_length, model_max_seq_length)
model = AutoModelForCausalLM.from_pretrained(
model_name,
device_map = device_map,
torch_dtype = dtype,
quantization_config = bnb_config,
token = token,
# rope_scaling = rope_scaling,
**kwargs,
)
tokenizer = AutoTokenizer.from_pretrained(
model_name,
model_max_length = max_position_embeddings,
padding_side = "right",
token = token,
)
model, tokenizer = patch_tokenizer(model, tokenizer)
model = FastMistralModel.post_patch(model)
# Patch up QKV / O and MLP
for idx, layer in enumerate(model.model.layers):
layer.self_attn.apply_qkv = original_apply_qkv
layer.self_attn.apply_o = original_apply_o
pass
# Save max_seq_length
max_position_embeddings = max(max_seq_length, model.config.max_position_embeddings)
model.max_seq_length = max_position_embeddings
internal_model = model
while hasattr(internal_model, "model"):
internal_model.max_seq_length = max_position_embeddings
internal_model = internal_model.model
pass
internal_model.max_seq_length = max_position_embeddings
# We check the tokenizer first for errors
if fix_tokenizer:
tokenizer = check_tokenizer(
model = model,
tokenizer = tokenizer,
model_name = model_name,
model_max_length = max_position_embeddings,
padding_side = "right",
token = token,
)
pass
patch_saving_functions(tokenizer)
# Fix up config for transformers uploading PEFT
# Not necessary anymore since we require transformers>=4.37
if False:
name = model.config._name_or_path
if name.startswith("unsloth/") and name.endswith("-bnb-4bit"):
name = name[:len(name) - len("-bnb-4bit")]
model.config.update({"_name_or_path" : name})
pass
# Log Unsloth version for future fastpaths for inference
model.config.update({"unsloth_version" : __version__})
# Add save modules
patch_saving_functions(model)
return model, tokenizer
pass
pass