attention.py 26 KB
Newer Older
chenxl's avatar
chenxl committed
1
2
3
4
5
6
7
8
9
'''
Description  :  
Author       : Boxin Zhang
Version      : 0.1.0
Copyright (c) 2024 by KVCache.AI, All Rights Reserved. 
'''
import torch
from torch import nn
import warnings
chenxl's avatar
chenxl committed
10
11
import torch.nn.functional as F
from ktransformers.operators.models import KLlamaModel
chenxl's avatar
chenxl committed
12
from ktransformers.models.configuration_deepseek import DeepseekV2Config
chenxl's avatar
chenxl committed
13
14
from ktransformers.models.configuration_llama import LlamaConfig
from ktransformers.models.modeling_llama import LlamaRotaryEmbedding
chenxl's avatar
chenxl committed
15
16
17
18
from ktransformers.models.modeling_deepseek import DeepseekV2Attention, apply_rotary_pos_emb
from typing import Optional, Tuple
from ktransformers.operators.base_operator import BaseInjectedModule
from ktransformers.util.custom_gguf import GGUFLoader
chenxl's avatar
chenxl committed
19
import logging
chenxl's avatar
chenxl committed
20
21
from transformers.configuration_utils import PretrainedConfig
from transformers.cache_utils import Cache
22
23
from flash_attn import flash_attn_with_kvcache, flash_attn_func
from ktransformers.operators.triton_attention import decode_attention_fwd_grouped
Atream's avatar
Atream committed
24
import os
chenxl's avatar
chenxl committed
25
logger = logging.getLogger("attention")
26

Atream's avatar
Atream committed
27
28
29
30
31
32
# Copied from transformers.models.llama.modeling_llama.rotate_half
def rotate_half(x):
    """Rotates half the hidden dims of the input."""
    x1 = x[..., : x.shape[-1] // 2]
    x2 = x[..., x.shape[-1] // 2 :]
    return torch.cat((-x2, x1), dim=-1)
33
34
35

# V3 MLA is same to V2
class KDeepseekV2Attention(BaseInjectedModule, DeepseekV2Attention):
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
    """Multi-headed attention from 'Attention Is All You Need' paper"""
    attn_mask: Optional[torch.Tensor] = None

    def __init__(self,
                 key: str,
                 gguf_loader : GGUFLoader,
                 config: PretrainedConfig,
                 orig_module: nn.Module,
                 device: str = "cuda",
                 chunck_size: int = 1000,
                 **kwargs):
        BaseInjectedModule.__init__(self, key, gguf_loader, config, orig_module, device, **kwargs)
        self.orig_module.__init__(orig_module.config,
            orig_module.layer_idx)
        self.chunck_size = chunck_size # TODO, generate chunck_size automatically.

    def get_absorbed(self) -> Tuple[torch.Tensor, torch.Tensor]:
        if not (hasattr(self, 'q_absorb') and hasattr(self, 'out_absorb')):
            kv_b_proj = self.kv_b_proj.weight.view(self.num_heads, -1, self.kv_lora_rank)
            q_absorb = kv_b_proj[:, :self.qk_nope_head_dim, :].reshape(-1, self.kv_lora_rank)
            out_absorb = kv_b_proj[:, self.qk_nope_head_dim:, :].reshape(-1, self.kv_lora_rank)
            self.q_absorb = nn.Linear(self.kv_lora_rank, self.num_heads * self.qk_nope_head_dim, 
                                      bias=False, dtype=q_absorb.dtype, device=q_absorb.device)
            self.q_absorb.weight.data = q_absorb
            self.out_absorb = nn.Linear(self.kv_lora_rank, self.num_heads * self.v_head_dim, 
                                        bias=False, dtype=out_absorb.dtype, device=out_absorb.device)
            self.out_absorb.weight.data = out_absorb
63
            #del self.orig_module.kv_b_proj
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
        q_absorb = self.q_absorb.weight.view(self.num_heads, self.qk_nope_head_dim, self.kv_lora_rank)
        out_absorb = self.out_absorb.weight.view(self.num_heads, self.v_head_dim, self.kv_lora_rank)
        return q_absorb, out_absorb

    def forward_chunck(
        self,
        hidden_states: torch.Tensor,
        attention_mask: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.LongTensor] = None,
        past_key_value: Optional[Cache] = None,
        output_attentions: bool = False,
        use_cache: bool = False,
        cache_position: Optional[torch.LongTensor] = None,
        **kwargs
    ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
        bsz, q_len, _ = hidden_states.size()
        if self.q_lora_rank is None:
            q = self.q_proj(hidden_states)
        else:
            q = self.q_b_proj(self.q_a_layernorm(self.q_a_proj(hidden_states)))
        q = q.view(bsz, q_len, self.num_heads, self.q_head_dim).transpose(1, 2)
        q_nope, q_pe = torch.split(
            q, [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1
        )
Atream's avatar
Atream committed
88
89
        # q_nope [bsz, self.num_heads, q_len, self.qk_nope_head_dim]
        # q_pe [bsz, self.num_heads, q_len, self.qk_rope_head_dim]
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108

        compressed_kv = self.kv_a_proj_with_mqa(hidden_states)
        compressed_kv, k_pe = torch.split(
            compressed_kv, [self.kv_lora_rank, self.qk_rope_head_dim], dim=-1
        )
        compressed_kv = self.kv_a_layernorm(compressed_kv)
        k_pe = k_pe.view(bsz, q_len, 1, self.qk_rope_head_dim).transpose(1, 2)

        kv_seq_len = k_pe.shape[-2]
        if past_key_value is not None:
            if self.layer_idx is None:
                raise ValueError(
                    f"The cache structure has changed since version v4.36. If you are using {self.__class__.__name__} "
                    "for auto-regressive decoding with k/v caching, please make sure to initialize the attention class "
                    "with a layer index."
                )
            kv_seq_len += past_key_value.get_usable_length(kv_seq_len, self.layer_idx)

        cos, sin = self.rotary_emb(q_pe, position_ids)
109
        q_pe, k_pe = apply_rotary_pos_emb(q_pe, k_pe, cos, sin)
110
111
112

        if past_key_value is not None:
            cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position}  # Specific to RoPE models
Atream's avatar
Atream committed
113
114
115
116
117
118
119
120
121
122
123
124
            
            # compressed_kv [bsz, q_len, self.kv_lora_rank]
            # k_pe [bsz, 1, q_len, self.qk_rope_head_dim]
            k_pe = k_pe.transpose(1,2)
            compressed_kv = compressed_kv.unsqueeze(2)
            compressed_kv_with_k_pe, _ = past_key_value.update(compressed_kv, k_pe, self.layer_idx, cache_kwargs)
            compressed_kv, k_pe = torch.split(
                compressed_kv_with_k_pe, [self.kv_lora_rank, self.qk_rope_head_dim], dim=-1
            )
            # k_pe [pages, page_size, 1, self.qk_rope_head_dim]
            # compressed_kv [pages, page_size, 1, self.kv_lora_rank]
            
125
        q_absorb, out_absorb = self.get_absorbed()
Atream's avatar
Atream committed
126
127
        if hasattr(self.orig_module, 'kv_b_proj'):
            del self.orig_module.kv_b_proj
128

Atream's avatar
Atream committed
129
130
131
132
133
134
        # q_nope [bsz, self.num_heads, q_len, self.qk_nope_head_dim]
        # q_pe [bsz, self.num_heads, q_len, self.qk_rope_head_dim]
        k_pe = k_pe.view(bsz, 1, -1, self.qk_rope_head_dim)[:,:,:attention_mask.size(-1),:]
        compressed_kv = compressed_kv.view(bsz, 1, -1, self.kv_lora_rank)[:,:,:attention_mask.size(-1),:]
        # k_pe [bsz, 1, cache_len, self.qk_rope_head_dim]
        # compressed_kv [bsz, 1, cache_len,self.kv_lora_rank]
135
        q_nope = torch.matmul(q_nope, q_absorb)
Atream's avatar
Atream committed
136
137
138
139
140
141
142
143
        #print(q_pe.shape)
        #print(k_pe.shape)
        #print(q_nope.shape)
        #print(compressed_kv.shape)
        
        attn_weights = (torch.matmul(q_pe, k_pe.mT) + torch.matmul(q_nope, compressed_kv.mT)) * self.softmax_scale
        #attn_weights [bsz, self.num_heads, q_len, kv_seq_len]
        compressed_kv = compressed_kv.squeeze(1)
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
        """
        if attn_weights.size() != (bsz, self.num_heads, q_len, kv_seq_len):
            raise ValueError(
                f"Attention weights should be of size {(bsz, self.num_heads, q_len, kv_seq_len)}, but is"
                f" {attn_weights.size()}"
            )
        assert attention_mask is not None
        """
        if attention_mask is not None:
            """
            if attention_mask.size() != (bsz, 1, q_len, kv_seq_len):
                raise ValueError(
                    f"Attention mask should be of size {(bsz, 1, q_len, kv_seq_len)}, but is {attention_mask.size()}"
                )
            """
            #causal_mask = attention_mask[:, :, :, : kv_seq_len]
            attn_weights = attn_weights + attention_mask

        # upcast attention to fp32
        attn_weights = nn.functional.softmax(
            attn_weights, dim=-1, dtype=torch.float32
        ).to(q_pe.dtype)
        attn_weights = nn.functional.dropout(
            attn_weights, p=self.attention_dropout, training=self.training
        )
        attn_output = torch.einsum('bhql,blc->bhqc', attn_weights, compressed_kv)

        attn_output = torch.matmul(attn_output, out_absorb.mT) 

        if attn_output.size() != (bsz, self.num_heads, q_len, self.v_head_dim):
            raise ValueError(
                f"`attn_output` should be of size {(bsz, self.num_heads, q_len, self.v_head_dim)}, but is"
                f" {attn_output.size()}"
            )

        attn_output = attn_output.transpose(1, 2).contiguous()

        attn_output = attn_output.reshape(bsz, q_len, self.num_heads * self.v_head_dim)

        attn_output = self.o_proj(attn_output)

185
        return attn_output, None, past_key_value
186

Atream's avatar
Atream committed
187
188
189
190
191
192
193
194
195
196
197
198
    def forward_linux(
            self,
            hidden_states: torch.Tensor,
            attention_mask: Optional[torch.Tensor] = None,
            position_ids: Optional[torch.LongTensor] = None,
            past_key_value: Optional[Cache] = None,
            output_attentions: bool = False,
            use_cache: bool = False,
            cache_position: Optional[torch.LongTensor] = None,
            **kwargs,
        ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:

chenxl's avatar
chenxl committed
199
        bsz, q_len, _ = hidden_states.size()
200

chenxl's avatar
chenxl committed
201
202
203
204
        if self.q_lora_rank is None:
            q = self.q_proj(hidden_states)
        else:
            q = self.q_b_proj(self.q_a_layernorm(self.q_a_proj(hidden_states)))
Atream's avatar
Atream committed
205
        q = q.view(bsz, q_len, self.num_heads, self.q_head_dim)
chenxl's avatar
chenxl committed
206
207
208
209
210
211
212
213
214
        q_nope, q_pe = torch.split(
            q, [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1
        )

        compressed_kv = self.kv_a_proj_with_mqa(hidden_states)
        compressed_kv, k_pe = torch.split(
            compressed_kv, [self.kv_lora_rank, self.qk_rope_head_dim], dim=-1
        )
        compressed_kv = self.kv_a_layernorm(compressed_kv)
Atream's avatar
Atream committed
215
        k_pe = k_pe.view(bsz, q_len, 1, self.qk_rope_head_dim)
216
217
        compressed_kv = compressed_kv.view(bsz, q_len, 1, self.kv_lora_rank)
        
chenxl's avatar
chenxl committed
218
        cos, sin = self.rotary_emb(q_pe, position_ids)
Atream's avatar
Atream committed
219
220
221
        q_pe, k_pe = apply_rotary_pos_emb(q_pe, k_pe, cos, sin, unsqueeze_dim=2)
        # q_pe [bsz, q_len, self.num_heads, self.qk_rope_head_dim] k_pe [bsz, q_len, 1, self.qk_rope_head_dim]
        
222
223
224
225
        # decode
        if q_len == 1:
            if past_key_value is not None:
                cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position}  # Specific to RoPE models
Atream's avatar
Atream committed
226
227
228
229
230
231
                compressed_kv_with_k_pe, page_table = past_key_value.update(compressed_kv, k_pe, self.layer_idx, cache_kwargs)
                compressed_kv = compressed_kv_with_k_pe [:, :, :, :self.kv_lora_rank] # for speed
                # compressed_kv_with_k_pe [bsz, q_len, 1, self.kv_lora_rank + self.qk_rope_head_dim]
                # compressed_kv [bsz, q_len, 1, self.kv_lora_rank]

            # q_nope [bsz, q_len, self.num_heads, self.qk_nope_head_dim]
232
233
            # q_absorb [self.num_heads, self.qk_nope_head_dim, self.kv_lora_rank]
            q_absorb, out_absorb = self.get_absorbed()
Atream's avatar
Atream committed
234
            q_nope = q_nope.transpose(1, 2) # q_len is 1, no GPU overhead, same below
235
            q_nope = torch.matmul(q_nope, q_absorb) # batched MM
Atream's avatar
Atream committed
236
237
238
239
240
            q_nope = q_nope.transpose(1, 2)
            assert q_nope.is_contiguous()
            
            # q_nope [bsz, q_len, self.num_heads, self.kv_lora_rank]
            # q_pe [bsz, q_len, self.num_heads, self.qk_rope_head_dim]
241
242
            query_states = torch.cat([q_nope, q_pe], dim=-1)
            
Atream's avatar
Atream committed
243
244
            query_states = query_states.squeeze(1)
            attn_output = torch.zeros_like(q_nope) # [bsz, q_len, self.num_heads, self.kv_lora_rank]
245
246
247
248
249
            
            attn_logits = torch.empty(
                    (
                        bsz,
                        self.num_heads,
Atream's avatar
Atream committed
250
                        4, #num_kv_splits # follow vLLM, fix it TODO
251
252
253
254
255
                        self.kv_lora_rank + 1, 
                    ),
                    dtype=torch.float32,
                    device = attn_output.device
                )
chenxl's avatar
chenxl committed
256
257

            """
258
            print("query_states", torch.isnan(query_states).any())
Atream's avatar
Atream committed
259
            print("compressed_kv_with_k_pe", torch.isnan(compressed_kv_with_k_pe[:,:,0,:]).any())
260
261
            print("compressed_kv", torch.isnan(compressed_kv[:,:,0,:]).any())
            print("position_ids", torch.isnan(position_ids).any())
chenxl's avatar
chenxl committed
262
263
            """

Atream's avatar
Atream committed
264
            # flash attn doesn't support head_dim bigger than 256
Atream's avatar
Atream committed
265
            # use triton attention kernel adapted from vLLM and SGLang for MQA
Atream's avatar
Atream committed
266
            decode_attention_fwd_grouped(query_states, compressed_kv_with_k_pe, compressed_kv, attn_output,
267
268
                             page_table,
                             position_ids.squeeze(0).to(torch.int32), attn_logits,
Atream's avatar
Atream committed
269
                             4, #num_kv_splits # follow vLLM, fix it TODO
270
271
272
                             self.softmax_scale,
                             past_key_value.page_size)
            
Atream's avatar
Atream committed
273
274
275
276
277
            # attn_output [bsz, q_len, self.num_heads, self.kv_lora_rank]
            # out_absorb [self.num_heads, self.v_head_dim, self.kv_lora_rank]
            attn_output = attn_output.transpose(1, 2)
            attn_output = torch.matmul(attn_output, out_absorb.mT)
            
278
279
280
281
282
283
284
285
286
287
            attn_output = attn_output.reshape(bsz, q_len, self.num_heads * self.v_head_dim)
            attn_output = self.o_proj(attn_output)
            
            #print("attn_output", torch.isnan(attn_output).any())
            return attn_output, None, past_key_value
        else:
            if past_key_value is not None:
                cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position}  # Specific to RoPE models
                k_pe.squeeze(0)
                compressed_kv.squeeze(0)
Atream's avatar
Atream committed
288
                past_key_value.update(compressed_kv, k_pe, self.layer_idx, cache_kwargs)
289
290
291
292
293
294
295
296
                k_pe.unsqueeze(0)
                compressed_kv.unsqueeze(0)
        
            k_pe = k_pe[:, :q_len]
            compressed_kv = compressed_kv[:, :q_len]
            kv = (
                self.kv_b_proj(compressed_kv)
                .view(bsz, q_len, self.num_heads, self.qk_nope_head_dim + self.v_head_dim)
chenxl's avatar
chenxl committed
297
            )
298
            k_nope, value_states = torch.split(kv, [self.qk_nope_head_dim, self.v_head_dim], dim=-1)
Atream's avatar
Atream committed
299
            query_states = k_pe.new_empty(bsz, q_len, self.num_heads, self.q_head_dim)
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
            query_states[:, :, :, : self.qk_nope_head_dim] = q_nope
            query_states[:, :, :, self.qk_nope_head_dim :] = q_pe

            key_states = k_pe.new_empty(bsz, q_len, self.num_heads, self.q_head_dim)
            key_states[:, :, :, :self.qk_nope_head_dim] = k_nope
            key_states[:, :, :, self.qk_nope_head_dim:] = k_pe
            
            value_states = value_states.view(bsz, q_len, self.num_heads, self.v_head_dim)
            value_states_padded = torch.nn.functional.pad(value_states, [0, query_states.shape[-1] - value_states.shape[-1]], value=0)

            attn_output = flash_attn_func(
                query_states,
                key_states,
                value_states_padded,
                softmax_scale=self.softmax_scale,
                causal=True,
chenxl's avatar
chenxl committed
316
317
            )

318
319
320
321
322
323
324
325
            if self.q_head_dim != self.v_head_dim:
                attn_output = attn_output[:, :, :, : self.v_head_dim]

            attn_output = attn_output.reshape(
                bsz, q_len, self.num_heads * self.v_head_dim
            ).contiguous()
            attn_output = self.o_proj(attn_output)
            return attn_output, None, past_key_value
Atream's avatar
Atream committed
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
        
    def forward_windows(
        self,
        hidden_states: torch.Tensor,
        attention_mask: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.LongTensor] = None,
        past_key_value: Optional[Cache] = None,
        output_attentions: bool = False,
        use_cache: bool = False,
        cache_position: Optional[torch.LongTensor] = None,
        **kwargs,
    ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
        if "padding_mask" in kwargs:
            warnings.warn(
                "Passing `padding_mask` is deprecated and will be removed in v4.37. Please make sure use `attention_mask` instead.`"
            )
        bsz, q_len, _ = hidden_states.size()
chenxl's avatar
chenxl committed
343

Atream's avatar
Atream committed
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
        if q_len <= self.chunck_size:
            return self.forward_chunck(
                            hidden_states,
                            attention_mask,
                            position_ids,
                            past_key_value,
                            output_attentions,
                            use_cache,
                            cache_position,
                            **kwargs
                        )

        assert output_attentions == False, "output_attentions is not supported when using chunked attention"
        attn_output = None
        cur_idx = 0
        while cur_idx < q_len:
            if attention_mask is not None:
                chunk_mask = attention_mask[:, :, cur_idx:min(cur_idx + self.chunck_size, q_len), ...]
            else:
                # generate chunk_mask automatically.
                self.attn_mask = \
                    torch.zeros(1, 1, self.chunck_size, past_key_value.max_cache_len, device=hidden_states.device) \
                        if self.attn_mask is None \
                            else self.attn_mask
                self.attn_mask[:, :, :, cur_idx:min(cur_idx+self.chunck_size, past_key_value.max_cache_len)] = \
                    -1e+38 * torch.triu(torch.ones(self.chunck_size, self.chunck_size, device=hidden_states.device), diagonal=1)\
                        [:,:min(self.chunck_size, min(past_key_value.max_cache_len-cur_idx, self.chunck_size))]
                self.attn_mask[:, :, :, cur_idx+self.chunck_size:] = -1e+38
                self.attn_mask[:, :, :, :cur_idx] = 0
                chunk_mask = torch.narrow(self.attn_mask, 2, 0, min(self.chunck_size, q_len-cur_idx))

            cur_output, _, _ = self.forward_chunck(
                            hidden_states[:, cur_idx:min(cur_idx + self.chunck_size, q_len), ...],
                            chunk_mask,
                            position_ids[:, cur_idx:min(cur_idx + self.chunck_size, q_len)],
                            past_key_value,
                            output_attentions,
                            use_cache,
                            cache_position[cur_idx:min(cur_idx + self.chunck_size, q_len)],
                            **kwargs
                        )
            cur_idx += self.chunck_size
            if attn_output is None:
                attn_output = cur_output
            else:
                attn_output = torch.cat((attn_output, cur_output), dim=-2)
                
        return attn_output, None, past_key_value

    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.LongTensor] = None,
        past_key_value: Optional[Cache] = None,
        output_attentions: bool = False,
        use_cache: bool = False,
        cache_position: Optional[torch.LongTensor] = None,
        **kwargs,
    ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
        if os.name == 'nt':
            return self.forward_windows(
                hidden_states,
                attention_mask,
                position_ids,
                past_key_value,
                output_attentions,
                use_cache,
                cache_position,
                **kwargs,
            )
        else:
            return self.forward_linux(
                hidden_states,
                attention_mask,
                position_ids,
                past_key_value,
                output_attentions,
                use_cache,
                cache_position,
                **kwargs,
            )
chenxl's avatar
chenxl committed
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553


class KLlamaAttention(BaseInjectedModule):
    """Multi-headed attention from 'Attention Is All You Need' paper"""

    def __init__(self,
                 key: str,
                 gguf_loader : GGUFLoader,
                 config: PretrainedConfig,
                 orig_module: nn.Module,
                 device: str = "cuda",
                 **kwargs):
        BaseInjectedModule.__init__(self, key, gguf_loader, config, orig_module, device, **kwargs)
        self.orig_module.__init__(orig_module.config,
            orig_module.layer_idx)
    def apply_rotary_pos_emb(self, q, k, cos, sin, position_ids=None, unsqueeze_dim=1):
        """Applies Rotary Position Embedding to the query and key tensors.

        Args:
            q (`torch.Tensor`): The query tensor.
            k (`torch.Tensor`): The key tensor.
            cos (`torch.Tensor`): The cosine part of the rotary embedding.
            sin (`torch.Tensor`): The sine part of the rotary embedding.
            position_ids (`torch.Tensor`, *optional*):
                Deprecated and unused.
            unsqueeze_dim (`int`, *optional*, defaults to 1):
                The 'unsqueeze_dim' argument specifies the dimension along which to unsqueeze cos[position_ids] and
                sin[position_ids] so that they can be properly broadcasted to the dimensions of q and k. For example, note
                that cos[position_ids] and sin[position_ids] have the shape [batch_size, seq_len, head_dim]. Then, if q and
                k have the shape [batch_size, heads, seq_len, head_dim], then setting unsqueeze_dim=1 makes
                cos[position_ids] and sin[position_ids] broadcastable to the shapes of q and k. Similarly, if q and k have
                the shape [batch_size, seq_len, heads, head_dim], then set unsqueeze_dim=2.
        Returns:
            `tuple(torch.Tensor)` comprising of the query and key tensors rotated using the Rotary Position Embedding.
        """
        cos = cos.unsqueeze(unsqueeze_dim)
        sin = sin.unsqueeze(unsqueeze_dim)
        q_embed = (q * cos) + (rotate_half(q) * sin)
        k_embed = (k * cos) + (rotate_half(k) * sin)
        return q_embed, k_embed
    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.LongTensor] = None,
        past_key_value: Optional[Cache] = None,
        output_attentions: bool = False,
        use_cache: bool = False,
        cache_position: Optional[torch.LongTensor] = None,
        position_embeddings: Optional[Tuple[torch.Tensor, torch.Tensor]] = None,  # will become mandatory in v4.45
        **kwargs,
    ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
        bsz, q_len, _ = hidden_states.size()

        if self.config.pretraining_tp > 1:
            key_value_slicing = (self.num_key_value_heads * self.head_dim) // self.config.pretraining_tp
            query_slices = self.q_proj.weight.split(
                (self.num_heads * self.head_dim) // self.config.pretraining_tp, dim=0
            )
            key_slices = self.k_proj.weight.split(key_value_slicing, dim=0)
            value_slices = self.v_proj.weight.split(key_value_slicing, dim=0)

            query_states = [F.linear(hidden_states, query_slices[i]) for i in range(self.config.pretraining_tp)]
            query_states = torch.cat(query_states, dim=-1)

            key_states = [F.linear(hidden_states, key_slices[i]) for i in range(self.config.pretraining_tp)]
            key_states = torch.cat(key_states, dim=-1)

            value_states = [F.linear(hidden_states, value_slices[i]) for i in range(self.config.pretraining_tp)]
            value_states = torch.cat(value_states, dim=-1)

        else:
            query_states = self.q_proj(hidden_states)
            key_states = self.k_proj(hidden_states)
            value_states = self.v_proj(hidden_states)

        query_states = query_states.view(bsz, q_len, self.num_heads, self.head_dim).transpose(1, 2)
        key_states = key_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
        value_states = value_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)

        if position_embeddings is None:

            logger.warning(
                "The attention layers in this model are transitioning from computing the RoPE embeddings internally "
                "through `position_ids` (2D tensor with the indexes of the tokens), to using externally computed "
                "`position_embeddings` (Tuple of tensors, containing cos and sin). In v4.45 `position_ids` will be "
                "removed and `position_embeddings` will be mandatory."
            )
            cos, sin = self.rotary_emb(value_states, position_ids)
        else:
            cos, sin = position_embeddings
        query_states, key_states = self.apply_rotary_pos_emb(query_states, key_states, cos, sin)
        if q_len == 1:
            position_ids = position_ids[0][-1].unsqueeze(0).unsqueeze(0)
            query_states = query_states[:, :, -1:]
            key_states = key_states[:, :, -1:]

        attn_output = KLlamaModel.dynamic_sdpa.apply(
            self.layer_idx,
            bsz,
            position_ids[0][0],
            query_states.transpose(1, 2).to(torch.float16),
            key_states.transpose(1, 2).to(torch.float16),
            value_states.transpose(1, 2).to(torch.float16),
            mode="prefill" if q_len > 1 else "generate",
        )


        if attn_output.size() != (bsz, self.num_heads, q_len, self.head_dim):
            raise ValueError(
                f"`attn_output` should be of size {(bsz, self.num_heads, q_len, self.head_dim)}, but is"
                f" {attn_output.size()}"
            )

        attn_output = attn_output.transpose(1, 2).contiguous()

        attn_output = attn_output.reshape(bsz, q_len, -1)

        if self.config.pretraining_tp > 1:
            attn_output = attn_output.split(self.hidden_size // self.config.pretraining_tp, dim=2)
            o_proj_slices = self.o_proj.weight.split(self.hidden_size // self.config.pretraining_tp, dim=1)
            attn_output = sum([F.linear(attn_output[i], o_proj_slices[i]) for i in range(self.config.pretraining_tp)])
        else:
            attn_output = self.o_proj(attn_output)

        if not output_attentions:
            attn_weights = None

Atream's avatar
Atream committed
554
        return attn_output, attn_weights, past_key_value