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1
+ import math
2
+ import warnings
3
+ from functools import partial
4
+ from typing import List, Optional, Tuple, Union
5
+
6
+ import torch
7
+ import torch.nn.functional as F
8
+ import torch.utils.checkpoint
9
+ from torch import nn
10
+
11
+
12
+ import copy
13
+ import os
14
+ import sys
15
+
16
+ dir_path = os.path.dirname(os.path.realpath(__file__))
17
+ sys.path.insert(0, dir_path)
18
+
19
+ import transformers
20
+ from transformers.models.llama.modeling_llama import *
21
+
22
+ def _get_unpad_data(attention_mask):
23
+ seqlens_in_batch = attention_mask.sum(dim=-1, dtype=torch.int32)
24
+ indices = torch.nonzero(attention_mask.flatten(), as_tuple=False).flatten()
25
+ max_seqlen_in_batch = seqlens_in_batch.max().item()
26
+ cu_seqlens = F.pad(torch.cumsum(seqlens_in_batch, dim=0, dtype=torch.torch.int32), (1, 0))
27
+ return (
28
+ indices,
29
+ cu_seqlens,
30
+ max_seqlen_in_batch,
31
+ )
32
+
33
+
34
+ from transformers.configuration_utils import PretrainedConfig
35
+ from transformers.utils import logging
36
+
37
+ from .modeling_attn_mask_utils import _prepare_4d_causal_attention_mask
38
+ from .configuration_mplug_owl2 import LlamaConfig
39
+
40
+ class MultiwayNetwork(nn.Module):
41
+
42
+ def __init__(self, module_provider, num_multiway=2):
43
+ super(MultiwayNetwork, self).__init__()
44
+
45
+ self.multiway = torch.nn.ModuleList([module_provider() for _ in range(num_multiway)])
46
+
47
+ def forward(self, hidden_states, multiway_indices):
48
+
49
+ if len(self.multiway) == 1:
50
+ return self.multiway[0](hidden_states)
51
+
52
+ output_hidden_states = torch.empty_like(hidden_states)
53
+
54
+ for idx, subway in enumerate(self.multiway):
55
+ local_indices = multiway_indices.eq(idx).nonzero(as_tuple=True)
56
+ hidden = hidden_states[local_indices].unsqueeze(1).contiguous()
57
+ if hidden.numel():
58
+ output = subway(hidden)
59
+ if isinstance(output, tuple):
60
+ output = output[0]
61
+ output = output.squeeze(1)
62
+ output_hidden_states[local_indices] = output
63
+
64
+ return output_hidden_states.contiguous()
65
+
66
+
67
+ class LlamaAttention(nn.Module):
68
+ """Multi-headed attention from 'Attention Is All You Need' paper"""
69
+
70
+ def __init__(self, config: LlamaConfig, layer_idx: Optional[int] = None):
71
+ super().__init__()
72
+ self.config = config
73
+ self.layer_idx = layer_idx
74
+ if layer_idx is None:
75
+ logger.warning_once(
76
+ f"Instantiating {self.__class__.__name__} without passing `layer_idx` is not recommended and will "
77
+ "to errors during the forward call, if caching is used. Please make sure to provide a `layer_idx` "
78
+ "when creating this class."
79
+ )
80
+
81
+ self.attention_dropout = config.attention_dropout
82
+ self.hidden_size = config.hidden_size
83
+ self.num_heads = config.num_attention_heads
84
+ self.head_dim = self.hidden_size // self.num_heads
85
+ self.num_key_value_heads = config.num_key_value_heads
86
+ self.num_key_value_groups = self.num_heads // self.num_key_value_heads
87
+ self.max_position_embeddings = config.max_position_embeddings
88
+ self.rope_theta = config.rope_theta
89
+ self.is_causal = True
90
+
91
+ if (self.head_dim * self.num_heads) != self.hidden_size:
92
+ raise ValueError(
93
+ f"hidden_size must be divisible by num_heads (got `hidden_size`: {self.hidden_size}"
94
+ f" and `num_heads`: {self.num_heads})."
95
+ )
96
+ self.q_proj = nn.Linear(self.hidden_size, self.num_heads * self.head_dim, bias=config.attention_bias)
97
+ self.k_proj = MultiwayNetwork(module_provider=partial(
98
+ nn.Linear, in_features=self.hidden_size, out_features=self.num_key_value_heads * self.head_dim, bias=config.attention_bias)
99
+ )
100
+ self.v_proj = MultiwayNetwork(module_provider=partial(
101
+ nn.Linear, in_features=self.hidden_size, out_features=self.num_key_value_heads * self.head_dim, bias=config.attention_bias)
102
+ )
103
+ self.o_proj = nn.Linear(self.num_heads * self.head_dim, self.hidden_size, bias=config.attention_bias)
104
+ self._init_rope()
105
+
106
+ def _init_rope(self):
107
+ if self.config.rope_scaling is None:
108
+ self.rotary_emb = LlamaRotaryEmbedding(
109
+ self.head_dim,
110
+ max_position_embeddings=self.max_position_embeddings,
111
+ base=self.rope_theta,
112
+ )
113
+ else:
114
+ scaling_type = self.config.rope_scaling["type"]
115
+ scaling_factor = self.config.rope_scaling["factor"]
116
+ if scaling_type == "linear":
117
+ self.rotary_emb = LlamaLinearScalingRotaryEmbedding(
118
+ self.head_dim,
119
+ max_position_embeddings=self.max_position_embeddings,
120
+ scaling_factor=scaling_factor,
121
+ base=self.rope_theta,
122
+ )
123
+ elif scaling_type == "dynamic":
124
+ self.rotary_emb = LlamaDynamicNTKScalingRotaryEmbedding(
125
+ self.head_dim,
126
+ max_position_embeddings=self.max_position_embeddings,
127
+ scaling_factor=scaling_factor,
128
+ base=self.rope_theta,
129
+ )
130
+ else:
131
+ raise ValueError(f"Unknown RoPE scaling type {scaling_type}")
132
+
133
+ def _shape(self, tensor: torch.Tensor, seq_len: int, bsz: int):
134
+ return tensor.view(bsz, seq_len, self.num_heads, self.head_dim).transpose(1, 2).contiguous()
135
+
136
+ def forward(
137
+ self,
138
+ hidden_states: torch.Tensor,
139
+ modality_indicators: torch.Tensor,
140
+ attention_mask: Optional[torch.Tensor] = None,
141
+ position_ids: Optional[torch.LongTensor] = None,
142
+ past_key_value: Optional[Tuple[torch.Tensor]] = None,
143
+ output_attentions: bool = False,
144
+ use_cache: bool = False,
145
+ padding_mask: Optional[torch.LongTensor] = None,
146
+ ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
147
+ bsz, q_len, _ = hidden_states.size()
148
+
149
+ query_states = self.q_proj(hidden_states, )
150
+ key_states = self.k_proj(hidden_states, modality_indicators)
151
+ value_states = self.v_proj(hidden_states, modality_indicators)
152
+
153
+ query_states = query_states.view(bsz, q_len, self.num_heads, self.head_dim).transpose(1, 2)
154
+ key_states = key_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
155
+ value_states = value_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
156
+
157
+ kv_seq_len = key_states.shape[-2]
158
+ if past_key_value is not None:
159
+ kv_seq_len += past_key_value[0].shape[-2]
160
+ cos, sin = self.rotary_emb(value_states, seq_len=kv_seq_len)
161
+ query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin, position_ids)
162
+
163
+ if past_key_value is not None:
164
+ # reuse k, v, self_attention
165
+ key_states = torch.cat([past_key_value[0], key_states], dim=2)
166
+ value_states = torch.cat([past_key_value[1], value_states], dim=2)
167
+
168
+ past_key_value = (key_states, value_states) if use_cache else None
169
+
170
+ key_states = repeat_kv(key_states, self.num_key_value_groups)
171
+ value_states = repeat_kv(value_states, self.num_key_value_groups)
172
+
173
+ attn_weights = torch.matmul(query_states, key_states.transpose(2, 3)) / math.sqrt(self.head_dim)
174
+
175
+ if attn_weights.size() != (bsz, self.num_heads, q_len, kv_seq_len):
176
+ raise ValueError(
177
+ f"Attention weights should be of size {(bsz, self.num_heads, q_len, kv_seq_len)}, but is"
178
+ f" {attn_weights.size()}"
179
+ )
180
+
181
+ if attention_mask is not None:
182
+ if attention_mask.size() != (bsz, 1, q_len, kv_seq_len):
183
+ raise ValueError(
184
+ f"Attention mask should be of size {(bsz, 1, q_len, kv_seq_len)}, but is {attention_mask.size()}"
185
+ )
186
+ attn_weights = attn_weights + attention_mask
187
+
188
+ # upcast attention to fp32
189
+ attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query_states.dtype)
190
+ attn_output = torch.matmul(attn_weights, value_states)
191
+
192
+ if attn_output.size() != (bsz, self.num_heads, q_len, self.head_dim):
193
+ raise ValueError(
194
+ f"`attn_output` should be of size {(bsz, self.num_heads, q_len, self.head_dim)}, but is"
195
+ f" {attn_output.size()}"
196
+ )
197
+
198
+ attn_output = attn_output.transpose(1, 2).contiguous()
199
+
200
+ attn_output = attn_output.reshape(bsz, q_len, self.hidden_size)
201
+
202
+ attn_output = self.o_proj(attn_output)
203
+
204
+ if not output_attentions:
205
+ attn_weights = None
206
+
207
+ return attn_output, attn_weights, past_key_value
208
+
209
+
210
+ class LlamaFlashAttention2(LlamaAttention):
211
+ """
212
+ Llama flash attention module. This module inherits from `LlamaAttention` as the weights of the module stays
213
+ untouched. The only required change would be on the forward pass where it needs to correctly call the public API of
214
+ flash attention and deal with padding tokens in case the input contains any of them.
215
+ """
216
+
217
+ def __init__(self, *args, **kwargs):
218
+ super().__init__(*args, **kwargs)
219
+
220
+ # TODO: Should be removed once Flash Attention for RoCm is bumped to 2.1.
221
+ # flash_attn<2.1 generates top-left aligned causal mask, while what is needed here is bottom-right alignement, that was made default for flash_attn>=2.1. This attribute is used to handle this difference. Reference: https://github.com/Dao-AILab/flash-attention/releases/tag/v2.1.0.
222
+ # Beware that with flash_attn<2.1, using q_seqlen != k_seqlen (except for the case q_seqlen == 1) produces a wrong mask (top-left).
223
+ self._flash_attn_uses_top_left_mask = not is_flash_attn_greater_or_equal_2_10()
224
+
225
+ def forward(
226
+ self,
227
+ hidden_states: torch.Tensor,
228
+ modality_indicators: torch.Tensor,
229
+ attention_mask: Optional[torch.LongTensor] = None,
230
+ position_ids: Optional[torch.LongTensor] = None,
231
+ past_key_value: Optional[Cache] = None,
232
+ output_attentions: bool = False,
233
+ use_cache: bool = False,
234
+ **kwargs,
235
+ ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
236
+ # LlamaFlashAttention2 attention does not support output_attentions
237
+ if "padding_mask" in kwargs:
238
+ warnings.warn(
239
+ "Passing `padding_mask` is deprecated and will be removed in v4.37. Please make sure use `attention_mask` instead.`"
240
+ )
241
+
242
+ # overwrite attention_mask with padding_mask
243
+ attention_mask = kwargs.pop("padding_mask")
244
+
245
+ output_attentions = False
246
+
247
+ bsz, q_len, _ = hidden_states.size()
248
+
249
+ query_states = self.q_proj(hidden_states)
250
+ key_states = self.k_proj(hidden_states, modality_indicators)
251
+ value_states = self.v_proj(hidden_states, modality_indicators)
252
+
253
+ # Flash attention requires the input to have the shape
254
+ # batch_size x seq_length x head_dim x hidden_dim
255
+ # therefore we just need to keep the original shape
256
+ query_states = query_states.view(bsz, q_len, self.num_heads, self.head_dim).transpose(1, 2)
257
+ key_states = key_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
258
+ value_states = value_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
259
+
260
+ kv_seq_len = key_states.shape[-2]
261
+ if past_key_value is not None:
262
+ kv_seq_len += past_key_value.get_usable_length(kv_seq_len, self.layer_idx)
263
+ cos, sin = self.rotary_emb(value_states, seq_len=kv_seq_len)
264
+ query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin, position_ids)
265
+
266
+ if past_key_value is not None:
267
+ cache_kwargs = {"sin": sin, "cos": cos} # Specific to RoPE models
268
+ key_states, value_states = past_key_value.update(key_states, value_states, self.layer_idx, cache_kwargs)
269
+
270
+ # TODO: These transpose are quite inefficient but Flash Attention requires the layout [batch_size, sequence_length, num_heads, head_dim]. We would need to refactor the KV cache
271
+ # to be able to avoid many of these transpose/reshape/view.
272
+ query_states = query_states.transpose(1, 2)
273
+ key_states = key_states.transpose(1, 2)
274
+ value_states = value_states.transpose(1, 2)
275
+
276
+ dropout_rate = self.attention_dropout if self.training else 0.0
277
+
278
+ # In PEFT, usually we cast the layer norms in float32 for training stability reasons
279
+ # therefore the input hidden states gets silently casted in float32. Hence, we need
280
+ # cast them back in the correct dtype just to be sure everything works as expected.
281
+ # This might slowdown training & inference so it is recommended to not cast the LayerNorms
282
+ # in fp32. (LlamaRMSNorm handles it correctly)
283
+
284
+ input_dtype = query_states.dtype
285
+ if input_dtype == torch.float32:
286
+ if torch.is_autocast_enabled():
287
+ target_dtype = torch.get_autocast_gpu_dtype()
288
+ # Handle the case where the model is quantized
289
+ elif hasattr(self.config, "_pre_quantization_dtype"):
290
+ target_dtype = self.config._pre_quantization_dtype
291
+ else:
292
+ target_dtype = self.q_proj.weight.dtype
293
+
294
+ logger.warning_once(
295
+ f"The input hidden states seems to be silently casted in float32, this might be related to"
296
+ f" the fact you have upcasted embedding or layer norm layers in float32. We will cast back the input in"
297
+ f" {target_dtype}."
298
+ )
299
+
300
+ query_states = query_states.to(target_dtype)
301
+ key_states = key_states.to(target_dtype)
302
+ value_states = value_states.to(target_dtype)
303
+
304
+ attn_output = self._flash_attention_forward(
305
+ query_states, key_states, value_states, attention_mask, q_len, dropout=dropout_rate
306
+ )
307
+
308
+ attn_output = attn_output.reshape(bsz, q_len, self.hidden_size).contiguous()
309
+ attn_output = self.o_proj(attn_output)
310
+
311
+ if not output_attentions:
312
+ attn_weights = None
313
+
314
+ return attn_output, attn_weights, past_key_value
315
+
316
+ def _flash_attention_forward(
317
+ self, query_states, key_states, value_states, attention_mask, query_length, dropout=0.0, softmax_scale=None
318
+ ):
319
+ """
320
+ Calls the forward method of Flash Attention - if the input hidden states contain at least one padding token
321
+ first unpad the input, then computes the attention scores and pad the final attention scores.
322
+
323
+ Args:
324
+ query_states (`torch.Tensor`):
325
+ Input query states to be passed to Flash Attention API
326
+ key_states (`torch.Tensor`):
327
+ Input key states to be passed to Flash Attention API
328
+ value_states (`torch.Tensor`):
329
+ Input value states to be passed to Flash Attention API
330
+ attention_mask (`torch.Tensor`):
331
+ The padding mask - corresponds to a tensor of size `(batch_size, seq_len)` where 0 stands for the
332
+ position of padding tokens and 1 for the position of non-padding tokens.
333
+ dropout (`int`, *optional*):
334
+ Attention dropout
335
+ softmax_scale (`float`, *optional*):
336
+ The scaling of QK^T before applying softmax. Default to 1 / sqrt(head_dim)
337
+ """
338
+ if not self._flash_attn_uses_top_left_mask:
339
+ causal = self.is_causal
340
+ else:
341
+ # TODO: Remove the `query_length != 1` check once Flash Attention for RoCm is bumped to 2.1. For details, please see the comment in LlamaFlashAttention2 __init__.
342
+ causal = self.is_causal and query_length != 1
343
+
344
+ # Contains at least one padding token in the sequence
345
+ if attention_mask is not None:
346
+ batch_size = query_states.shape[0]
347
+ query_states, key_states, value_states, indices_q, cu_seq_lens, max_seq_lens = self._upad_input(
348
+ query_states, key_states, value_states, attention_mask, query_length
349
+ )
350
+
351
+ cu_seqlens_q, cu_seqlens_k = cu_seq_lens
352
+ max_seqlen_in_batch_q, max_seqlen_in_batch_k = max_seq_lens
353
+
354
+ attn_output_unpad = flash_attn_varlen_func(
355
+ query_states,
356
+ key_states,
357
+ value_states,
358
+ cu_seqlens_q=cu_seqlens_q,
359
+ cu_seqlens_k=cu_seqlens_k,
360
+ max_seqlen_q=max_seqlen_in_batch_q,
361
+ max_seqlen_k=max_seqlen_in_batch_k,
362
+ dropout_p=dropout,
363
+ softmax_scale=softmax_scale,
364
+ causal=causal,
365
+ )
366
+
367
+ attn_output = pad_input(attn_output_unpad, indices_q, batch_size, query_length)
368
+ else:
369
+ attn_output = flash_attn_func(
370
+ query_states, key_states, value_states, dropout, softmax_scale=softmax_scale, causal=causal
371
+ )
372
+
373
+ return attn_output
374
+
375
+ def _upad_input(self, query_layer, key_layer, value_layer, attention_mask, query_length):
376
+ indices_k, cu_seqlens_k, max_seqlen_in_batch_k = _get_unpad_data(attention_mask)
377
+ batch_size, kv_seq_len, num_key_value_heads, head_dim = key_layer.shape
378
+
379
+ key_layer = index_first_axis(
380
+ key_layer.reshape(batch_size * kv_seq_len, num_key_value_heads, head_dim), indices_k
381
+ )
382
+ value_layer = index_first_axis(
383
+ value_layer.reshape(batch_size * kv_seq_len, num_key_value_heads, head_dim), indices_k
384
+ )
385
+ if query_length == kv_seq_len:
386
+ query_layer = index_first_axis(
387
+ query_layer.reshape(batch_size * kv_seq_len, self.num_heads, head_dim), indices_k
388
+ )
389
+ cu_seqlens_q = cu_seqlens_k
390
+ max_seqlen_in_batch_q = max_seqlen_in_batch_k
391
+ indices_q = indices_k
392
+ elif query_length == 1:
393
+ max_seqlen_in_batch_q = 1
394
+ cu_seqlens_q = torch.arange(
395
+ batch_size + 1, dtype=torch.int32, device=query_layer.device
396
+ ) # There is a memcpy here, that is very bad.
397
+ indices_q = cu_seqlens_q[:-1]
398
+ query_layer = query_layer.squeeze(1)
399
+ else:
400
+ # The -q_len: slice assumes left padding.
401
+ attention_mask = attention_mask[:, -query_length:]
402
+ query_layer, indices_q, cu_seqlens_q, max_seqlen_in_batch_q = unpad_input(query_layer, attention_mask)
403
+
404
+ return (
405
+ query_layer,
406
+ key_layer,
407
+ value_layer,
408
+ indices_q,
409
+ (cu_seqlens_q, cu_seqlens_k),
410
+ (max_seqlen_in_batch_q, max_seqlen_in_batch_k),
411
+ )
412
+
413
+
414
+ class LlamaSdpaAttention(LlamaAttention):
415
+ """
416
+ Llama attention module using torch.nn.functional.scaled_dot_product_attention. This module inherits from
417
+ `LlamaAttention` as the weights of the module stays untouched. The only changes are on the forward pass to adapt to
418
+ SDPA API.
419
+ """
420
+
421
+ # Adapted from LlamaAttention.forward
422
+ def forward(
423
+ self,
424
+ hidden_states: torch.Tensor,
425
+ modality_indicators: torch.Tensor,
426
+ attention_mask: Optional[torch.Tensor] = None,
427
+ position_ids: Optional[torch.LongTensor] = None,
428
+ past_key_value: Optional[Cache] = None,
429
+ output_attentions: bool = False,
430
+ use_cache: bool = False,
431
+ ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
432
+ if output_attentions:
433
+ # TODO: Improve this warning with e.g. `model.config.attn_implementation = "manual"` once this is implemented.
434
+ logger.warning_once(
435
+ "LlamaModel is using LlamaSdpaAttention, but `torch.nn.functional.scaled_dot_product_attention` does not support `output_attentions=True`. Falling back to the manual attention implementation, "
436
+ 'but specifying the manual implementation will be required from Transformers version v5.0.0 onwards. This warning can be removed using the argument `attn_implementation="eager"` when loading the model.'
437
+ )
438
+ return super().forward(
439
+ hidden_states=hidden_states,
440
+ modality_indicators=modality_indicators,
441
+ attention_mask=attention_mask,
442
+ position_ids=position_ids,
443
+ past_key_value=past_key_value,
444
+ output_attentions=output_attentions,
445
+ use_cache=use_cache,
446
+ )
447
+
448
+ bsz, q_len, _ = hidden_states.size()
449
+
450
+ query_states = self.q_proj(hidden_states)
451
+ key_states = self.k_proj(hidden_states, modality_indicators)
452
+ value_states = self.v_proj(hidden_states, modality_indicators)
453
+
454
+ query_states = query_states.view(bsz, q_len, self.num_heads, self.head_dim).transpose(1, 2)
455
+ key_states = key_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
456
+ value_states = value_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
457
+
458
+ kv_seq_len = key_states.shape[-2]
459
+ if past_key_value is not None:
460
+ kv_seq_len += past_key_value.get_usable_length(kv_seq_len, self.layer_idx)
461
+ cos, sin = self.rotary_emb(value_states, seq_len=kv_seq_len)
462
+
463
+ query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin, position_ids)
464
+
465
+ if past_key_value is not None:
466
+ cache_kwargs = {"sin": sin, "cos": cos} # Specific to RoPE models
467
+ key_states, value_states = past_key_value.update(key_states, value_states, self.layer_idx, cache_kwargs)
468
+
469
+ key_states = repeat_kv(key_states, self.num_key_value_groups)
470
+ value_states = repeat_kv(value_states, self.num_key_value_groups)
471
+
472
+ if attention_mask is not None:
473
+ if attention_mask.size() != (bsz, 1, q_len, kv_seq_len):
474
+ raise ValueError(
475
+ f"Attention mask should be of size {(bsz, 1, q_len, kv_seq_len)}, but is {attention_mask.size()}"
476
+ )
477
+
478
+ # SDPA with memory-efficient backend is currently (torch==2.1.2) bugged with non-contiguous inputs with custom attn_mask,
479
+ # Reference: https://github.com/pytorch/pytorch/issues/112577.
480
+ if query_states.device.type == "cuda" and attention_mask is not None:
481
+ query_states = query_states.contiguous()
482
+ key_states = key_states.contiguous()
483
+ value_states = value_states.contiguous()
484
+
485
+ attn_output = torch.nn.functional.scaled_dot_product_attention(
486
+ query_states,
487
+ key_states,
488
+ value_states,
489
+ attn_mask=attention_mask,
490
+ dropout_p=self.attention_dropout if self.training else 0.0,
491
+ # The q_len > 1 is necessary to match with AttentionMaskConverter.to_causal_4d that does not create a causal mask in case q_len == 1.
492
+ is_causal=self.is_causal and attention_mask is None and q_len > 1,
493
+ )
494
+
495
+ attn_output = attn_output.transpose(1, 2).contiguous()
496
+ attn_output = attn_output.reshape(bsz, q_len, self.hidden_size)
497
+
498
+ attn_output = self.o_proj(attn_output)
499
+
500
+ return attn_output, None, past_key_value
501
+
502
+
503
+
504
+ LLAMA_ATTENTION_CLASSES = {
505
+ "eager": LlamaAttention,
506
+ "flash_attention_2": LlamaFlashAttention2,
507
+ "sdpa": LlamaSdpaAttention,
508
+ }
509
+
510
+ class LlamaDecoderLayer(nn.Module):
511
+ def __init__(self, config: LlamaConfig, layer_idx):
512
+ super().__init__()
513
+ self.hidden_size = config.hidden_size
514
+ self.self_attn = LlamaAttention(config=config)
515
+ self.self_attn = LLAMA_ATTENTION_CLASSES[config._attn_implementation](config=config, layer_idx=layer_idx)
516
+ self.mlp = LlamaMLP(config)
517
+ self.input_layernorm = MultiwayNetwork(module_provider=partial(
518
+ LlamaRMSNorm, hidden_size=config.hidden_size, eps=config.rms_norm_eps
519
+ ))
520
+ self.post_attention_layernorm = MultiwayNetwork(module_provider=partial(
521
+ LlamaRMSNorm, hidden_size=config.hidden_size, eps=config.rms_norm_eps
522
+ ))
523
+
524
+ def forward(
525
+ self,
526
+ hidden_states: torch.Tensor,
527
+ modality_indicators: torch.Tensor = None,
528
+ attention_mask: Optional[torch.Tensor] = None,
529
+ position_ids: Optional[torch.LongTensor] = None,
530
+ past_key_value: Optional[Tuple[torch.Tensor]] = None,
531
+ output_attentions: Optional[bool] = False,
532
+ use_cache: Optional[bool] = False,
533
+ ) -> Tuple[torch.FloatTensor, Optional[Tuple[torch.FloatTensor, torch.FloatTensor]]]:
534
+ """
535
+ Args:
536
+ hidden_states (`torch.FloatTensor`): input to the layer of shape `(batch, seq_len, embed_dim)`
537
+ attention_mask (`torch.FloatTensor`, *optional*): attention mask of size
538
+ `(batch, 1, tgt_len, src_len)` where padding elements are indicated by very large negative values.
539
+ output_attentions (`bool`, *optional*):
540
+ Whether or not to return the attentions tensors of all attention layers. See `attentions` under
541
+ returned tensors for more detail.
542
+ use_cache (`bool`, *optional*):
543
+ If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding
544
+ (see `past_key_values`).
545
+ past_key_value (`Tuple(torch.FloatTensor)`, *optional*): cached past key and value projection states
546
+ """
547
+
548
+ residual = hidden_states
549
+
550
+ hidden_states = self.input_layernorm(hidden_states, modality_indicators)
551
+
552
+ # Self Attention
553
+ hidden_states, self_attn_weights, present_key_value = self.self_attn(
554
+ hidden_states=hidden_states,
555
+ modality_indicators=modality_indicators,
556
+ attention_mask=attention_mask,
557
+ position_ids=position_ids,
558
+ past_key_value=past_key_value,
559
+ output_attentions=output_attentions,
560
+ use_cache=use_cache,
561
+ )
562
+ hidden_states = residual + hidden_states
563
+
564
+ # Fully Connected
565
+ residual = hidden_states
566
+ hidden_states = self.post_attention_layernorm(hidden_states, modality_indicators)
567
+ hidden_states = self.mlp(hidden_states)
568
+ hidden_states = residual + hidden_states
569
+
570
+ outputs = (hidden_states,)
571
+
572
+ if output_attentions:
573
+ outputs += (self_attn_weights,)
574
+
575
+ if use_cache:
576
+ outputs += (present_key_value,)
577
+
578
+ return outputs
579
+
580
+
581
+ def model_forward(
582
+ self,
583
+ input_ids: torch.LongTensor = None,
584
+ modality_indicators: torch.Tensor = None,
585
+ attention_mask: Optional[torch.Tensor] = None,
586
+ position_ids: Optional[torch.LongTensor] = None,
587
+ past_key_values: Optional[List[torch.FloatTensor]] = None,
588
+ inputs_embeds: Optional[torch.FloatTensor] = None,
589
+ use_cache: Optional[bool] = None,
590
+ output_attentions: Optional[bool] = None,
591
+ output_hidden_states: Optional[bool] = None,
592
+ return_dict: Optional[bool] = None,
593
+ ) -> Union[Tuple, BaseModelOutputWithPast]:
594
+ output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
595
+ output_hidden_states = (
596
+ output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
597
+ )
598
+ use_cache = use_cache if use_cache is not None else self.config.use_cache
599
+
600
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
601
+
602
+ # retrieve input_ids and inputs_embeds
603
+ if input_ids is not None and inputs_embeds is not None:
604
+ raise ValueError("You cannot specify both decoder_input_ids and decoder_inputs_embeds at the same time")
605
+ elif input_ids is not None:
606
+ batch_size, seq_length = input_ids.shape
607
+ elif inputs_embeds is not None:
608
+ batch_size, seq_length, _ = inputs_embeds.shape
609
+ else:
610
+ raise ValueError("You have to specify either decoder_input_ids or decoder_inputs_embeds")
611
+
612
+ seq_length_with_past = seq_length
613
+ past_key_values_length = 0
614
+
615
+ if past_key_values is not None:
616
+ past_key_values_length = past_key_values[0][0].shape[2]
617
+ seq_length_with_past = seq_length_with_past + past_key_values_length
618
+
619
+ if position_ids is None:
620
+ device = input_ids.device if input_ids is not None else inputs_embeds.device
621
+ position_ids = torch.arange(
622
+ past_key_values_length, seq_length + past_key_values_length, dtype=torch.long, device=device
623
+ )
624
+ position_ids = position_ids.unsqueeze(0).view(-1, seq_length)
625
+ else:
626
+ position_ids = position_ids.view(-1, seq_length).long()
627
+
628
+ if inputs_embeds is None:
629
+ inputs_embeds = self.embed_tokens(input_ids)
630
+ # embed positions
631
+ if attention_mask is None:
632
+ attention_mask = torch.ones(
633
+ (batch_size, seq_length_with_past), dtype=torch.bool, device=inputs_embeds.device
634
+ )
635
+
636
+ if self._use_flash_attention_2:
637
+ # 2d mask is passed through the layers
638
+ attention_mask = attention_mask if (attention_mask is not None and 0 in attention_mask) else None
639
+ elif self._use_sdpa and not output_attentions:
640
+ # output_attentions=True can not be supported when using SDPA, and we fall back on
641
+ # the manual implementation that requires a 4D causal mask in all cases.
642
+ attention_mask = _prepare_4d_causal_attention_mask_for_sdpa(
643
+ attention_mask,
644
+ (batch_size, seq_length),
645
+ inputs_embeds,
646
+ past_key_values_length,
647
+ )
648
+ else:
649
+ # 4d mask is passed through the layers
650
+ attention_mask = _prepare_4d_causal_attention_mask(
651
+ attention_mask, (batch_size, seq_length), inputs_embeds, past_key_values_length
652
+ )
653
+
654
+ hidden_states = inputs_embeds
655
+
656
+ if self.gradient_checkpointing and self.training:
657
+ if use_cache:
658
+ logger.warning_once(
659
+ "`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`..."
660
+ )
661
+ use_cache = False
662
+
663
+ # decoder layers
664
+ all_hidden_states = () if output_hidden_states else None
665
+ all_self_attns = () if output_attentions else None
666
+ next_decoder_cache = () if use_cache else None
667
+
668
+ for idx, decoder_layer in enumerate(self.layers):
669
+ if output_hidden_states:
670
+ all_hidden_states += (hidden_states,)
671
+
672
+ past_key_value = past_key_values[idx] if past_key_values is not None else None
673
+
674
+ if self.gradient_checkpointing and self.training:
675
+
676
+ def create_custom_forward(module):
677
+ def custom_forward(*inputs):
678
+ # None for past_key_value
679
+ return module(*inputs, past_key_value, output_attentions)
680
+
681
+ return custom_forward
682
+
683
+ layer_outputs = torch.utils.checkpoint.checkpoint(
684
+ create_custom_forward(decoder_layer),
685
+ hidden_states,
686
+ modality_indicators,
687
+ attention_mask,
688
+ position_ids,
689
+ )
690
+ else:
691
+ layer_outputs = decoder_layer(
692
+ hidden_states,
693
+ modality_indicators=modality_indicators,
694
+ attention_mask=attention_mask,
695
+ position_ids=position_ids,
696
+ past_key_value=past_key_value,
697
+ output_attentions=output_attentions,
698
+ use_cache=use_cache,
699
+ )
700
+
701
+ hidden_states = layer_outputs[0]
702
+
703
+ if use_cache:
704
+ next_decoder_cache += (layer_outputs[2 if output_attentions else 1],)
705
+
706
+ if output_attentions:
707
+ all_self_attns += (layer_outputs[1],)
708
+
709
+ hidden_states = self.norm(hidden_states)
710
+
711
+ # add hidden states from the last decoder layer
712
+ if output_hidden_states:
713
+ all_hidden_states += (hidden_states,)
714
+
715
+ next_cache = next_decoder_cache if use_cache else None
716
+ if not return_dict:
717
+ return tuple(v for v in [hidden_states, next_cache, all_hidden_states, all_self_attns] if v is not None)
718
+ return BaseModelOutputWithPast(
719
+ last_hidden_state=hidden_states,
720
+ past_key_values=next_cache,
721
+ hidden_states=all_hidden_states,
722
+ attentions=all_self_attns,
723
+ )
724
+
725
+
726
+ def causal_model_forward(
727
+ self,
728
+ input_ids: torch.LongTensor = None,
729
+ modality_indicators: torch.Tensor = None,
730
+ attention_mask: Optional[torch.Tensor] = None,
731
+ position_ids: Optional[torch.LongTensor] = None,
732
+ past_key_values: Optional[List[torch.FloatTensor]] = None,
733
+ inputs_embeds: Optional[torch.FloatTensor] = None,
734
+ labels: Optional[torch.LongTensor] = None,
735
+ use_cache: Optional[bool] = None,
736
+ output_attentions: Optional[bool] = None,
737
+ output_hidden_states: Optional[bool] = None,
738
+ return_dict: Optional[bool] = None,
739
+ ) -> Union[Tuple, CausalLMOutputWithPast]:
740
+ r"""
741
+ Args:
742
+ labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
743
+ Labels for computing the masked language modeling loss. Indices should either be in `[0, ...,
744
+ config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored
745
+ (masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`.
746
+
747
+ Returns:
748
+
749
+ Example:
750
+
751
+ ```python
752
+ >>> from transformers import AutoTokenizer, LlamaForCausalLM
753
+
754
+ >>> model = LlamaForCausalLM.from_pretrained(PATH_TO_CONVERTED_WEIGHTS)
755
+ >>> tokenizer = AutoTokenizer.from_pretrained(PATH_TO_CONVERTED_TOKENIZER)
756
+
757
+ >>> prompt = "Hey, are you conscious? Can you talk to me?"
758
+ >>> inputs = tokenizer(prompt, return_tensors="pt")
759
+
760
+ >>> # Generate
761
+ >>> generate_ids = model.generate(inputs.input_ids, max_length=30)
762
+ >>> tokenizer.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0]
763
+ "Hey, are you conscious? Can you talk to me?\nI'm not conscious, but I can talk to you."
764
+ ```"""
765
+
766
+ output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
767
+ output_hidden_states = (
768
+ output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
769
+ )
770
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
771
+
772
+ # decoder outputs consists of (dec_features, layer_state, dec_hidden, dec_attn)
773
+ outputs = self.model(
774
+ input_ids=input_ids,
775
+ modality_indicators=modality_indicators,
776
+ attention_mask=attention_mask,
777
+ position_ids=position_ids,
778
+ past_key_values=past_key_values,
779
+ inputs_embeds=inputs_embeds,
780
+ use_cache=use_cache,
781
+ output_attentions=output_attentions,
782
+ output_hidden_states=output_hidden_states,
783
+ return_dict=return_dict,
784
+ )
785
+
786
+ hidden_states = outputs[0]
787
+ if self.config.pretraining_tp > 1:
788
+ lm_head_slices = self.lm_head.weight.split(self.vocab_size // self.config.pretraining_tp, dim=0)
789
+ logits = [F.linear(hidden_states, lm_head_slices[i]) for i in range(self.config.pretraining_tp)]
790
+ logits = torch.cat(logits, dim=-1)
791
+ else:
792
+ logits = self.lm_head(hidden_states)
793
+ logits = logits.float()
794
+
795
+ loss = None
796
+ if labels is not None:
797
+ # Shift so that tokens < n predict n
798
+ shift_logits = logits[..., :-1, :].contiguous()
799
+ shift_labels = labels[..., 1:].contiguous()
800
+ # Flatten the tokens
801
+ loss_fct = CrossEntropyLoss()
802
+ shift_logits = shift_logits.view(-1, self.config.vocab_size)
803
+ shift_labels = shift_labels.view(-1)
804
+ # Enable model parallelism
805
+ shift_labels = shift_labels.to(shift_logits.device)
806
+ loss = loss_fct(shift_logits, shift_labels)
807
+
808
+ if not return_dict:
809
+ output = (logits,) + outputs[1:]
810
+ return (loss,) + output if loss is not None else output
811
+
812
+ return CausalLMOutputWithPast(
813
+ loss=loss,
814
+ logits=logits,
815
+ past_key_values=outputs.past_key_values,
816
+ hidden_states=outputs.hidden_states,
817
+ attentions=outputs.attentions,
818
+ )
819
+
820
+ def replace_llama_modality_adaptive():
821
+ transformers.models.llama.configuration_llama.LlamaConfig = LlamaConfig
822
+ transformers.models.llama.modeling_llama.LlamaAttention = LlamaAttention
823
+ transformers.models.llama.modeling_llama.LlamaFlashAttention2 = LlamaFlashAttention2
824
+ transformers.models.llama.modeling_llama.LlamaSdpaAttention = LlamaSdpaAttention
825
+ transformers.models.llama.modeling_llama.LlamaDecoderLayer = LlamaDecoderLayer
826
+ transformers.models.llama.modeling_llama.LlamaModel.forward = model_forward
827
+ transformers.models.llama.modeling_llama.LlamaForCausalLM.forward = causal_model_forward
828
+
829
+
830
+ if __name__ == "__main__":
831
+ replace_llama_modality_adaptive()
832
+ config = transformers.LlamaConfig.from_pretrained('/cpfs01/shared/public/test/vicuna-7b-v1.5/')
833
+ model = transformers.LlamaForCausalLM(config)
834
+ print(model)