layers.py 28.1 KB
Newer Older
1
import os
2
import torch
3
import torch.distributed
4
5

from torch import nn
6
from torch.nn import functional as F
7
from typing import List
8
9
from loguru import logger
from functools import lru_cache
10
11
12

HAS_BITS_AND_BYTES = True
try:
13
    import bitsandbytes as bnb
Nicolas Patry's avatar
Nicolas Patry committed
14
    from bitsandbytes.nn import Int8Params, Params4bit
15
16

except ImportError:
17
18
    HAS_BITS_AND_BYTES = False

19
20
from accelerate import init_empty_weights

21
from text_generation_server.utils.gptq.quant_linear import QuantLinear
22

23
24

HAS_AWQ = True
OlivierDehaene's avatar
OlivierDehaene committed
25
try:
26
27
28
29
    from text_generation_server.utils.awq.quantize.qmodule import WQLinear
except ImportError:
    HAS_AWQ = False

30
try:
31
32
33
34
35
36
    major, _minor = torch.cuda.get_device_capability()
except Exception:
    major = 1
HAS_EXLLAMA = False
CAN_EXLLAMA = major >= 8
if os.getenv("DISABLE_EXLLAMA") == "True":
37
    HAS_EXLLAMA = False
38
elif CAN_EXLLAMA:
OlivierDehaene's avatar
OlivierDehaene committed
39
40
41
42
43
44
    try:
        from text_generation_server.utils.gptq.exllama import Ex4bitLinear

        HAS_EXLLAMA = True
    except ImportError:
        pass
45

46
from typing import Optional
47

48
49
50
HAS_EETQ = False
try:
    from EETQ import quant_weights, w8_a16_gemm
OlivierDehaene's avatar
OlivierDehaene committed
51

52
53
54
55
    HAS_EETQ = True
except ImportError:
    pass

56

57
58
59
60
61
62
63
64
65
66
67
68
69
# Monkey patching
@classmethod
def load_layer_norm(cls, prefix, weights, eps):
    weight = weights.get_tensor(f"{prefix}.weight")
    bias = weights.get_tensor(f"{prefix}.bias")
    with init_empty_weights():
        ln = cls(weight.shape, eps=eps)

    ln.weight = nn.Parameter(weight)
    ln.bias = nn.Parameter(bias)
    return ln


70
71
72
73
74
75
76
77
78
79
@classmethod
def load_layer_norm_no_bias(cls, prefix, weights, eps):
    weight = weights.get_tensor(f"{prefix}.weight")
    with init_empty_weights():
        ln = cls(weight.shape, eps=eps)

    ln.weight = nn.Parameter(weight)
    ln.bias = None
    return ln

OlivierDehaene's avatar
OlivierDehaene committed
80

81
82
83
84
85
@classmethod
def load_conv2d(cls, prefix, weights, in_channels, out_channels, kernel_size, stride):
    weight = weights.get_tensor(f"{prefix}.weight")
    bias = weights.get_tensor(f"{prefix}.bias")
    with init_empty_weights():
OlivierDehaene's avatar
OlivierDehaene committed
86
87
88
89
90
91
        conv2d = cls(
            in_channels=in_channels,
            out_channels=out_channels,
            kernel_size=kernel_size,
            stride=stride,
        )
92
93
94
95
96
97
98

    conv2d.weight = nn.Parameter(weight)
    conv2d.bias = nn.Parameter(bias)
    return conv2d


@classmethod
OlivierDehaene's avatar
OlivierDehaene committed
99
100
101
def load_conv2d_no_bias(
    cls, prefix, weights, in_channels, out_channels, kernel_size, stride
):
102
103
    weight = weights.get_tensor(f"{prefix}.weight")
    with init_empty_weights():
OlivierDehaene's avatar
OlivierDehaene committed
104
105
106
107
108
109
        conv2d = cls(
            in_channels=in_channels,
            out_channels=out_channels,
            kernel_size=kernel_size,
            stride=stride,
        )
110
111
112
113
114

    conv2d.weight = nn.Parameter(weight)
    conv2d.bias = None
    return conv2d

115

116
117
torch.nn.Conv2d.load = load_conv2d
torch.nn.Conv2d.load_no_bias = load_conv2d_no_bias
118
torch.nn.LayerNorm.load = load_layer_norm
119
torch.nn.LayerNorm.load_no_bias = load_layer_norm_no_bias
120

121
122

class FastLinear(nn.Module):
123
124
    def __init__(
        self,
125
126
        weight,
        bias,
127
    ) -> None:
128
129
130
131
132
        super().__init__()
        self.weight = nn.Parameter(weight)
        if bias is not None:
            self.bias = nn.Parameter(bias)
        else:
133
            self.bias = None
134
135
136
137
138
139

    @classmethod
    def load(cls, config, prefix: str, weights, bias: bool):
        weight = weights.get_tensor(f"{prefix}.weight")
        if bias:
            bias = weights.get_tensor(f"{prefix}.bias")
140
        else:
141
142
            bias = None
        return cls(weight, bias)
143
144

    def forward(self, input: torch.Tensor) -> torch.Tensor:
145
        return F.linear(input, self.weight, self.bias)
146
147


148
149
150
151
152
153
154
155
156
157
class EETQLinear(nn.Module):
    def __init__(
        self,
        weight,
        bias,
    ) -> None:
        super().__init__()
        device = weight.device
        weight = torch.t(weight).contiguous().cpu()
        weight, scale = quant_weights(weight, torch.int8, False)
158

159
160
161
162
163
164
165
166
167
168
        self.weight = weight.cuda(device)
        self.scale = scale.cuda(device)
        self.bias = bias.cuda(device) if bias is not None else None

    def forward(self, input: torch.Tensor) -> torch.Tensor:
        output = w8_a16_gemm(input, self.weight, self.scale)
        output = output + self.bias if self.bias is not None else output
        return output


169
class Linear8bitLt(nn.Module):
170
171
    def __init__(
        self,
172
173
174
175
176
177
        weight,
        bias,
        has_fp16_weights=True,
        memory_efficient_backward=False,
        threshold=0.0,
        index=None,
178
    ):
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
        super().__init__()
        assert (
            not memory_efficient_backward
        ), "memory_efficient_backward is no longer required and the argument is deprecated in 0.37.0 and will be removed in 0.39.0"
        self.state = bnb.MatmulLtState()
        self.index = index

        # Necessary for stacked layers
        self.state.threshold = threshold
        self.state.has_fp16_weights = has_fp16_weights
        self.state.memory_efficient_backward = memory_efficient_backward
        if threshold > 0.0 and not has_fp16_weights:
            self.state.use_pool = True

        self.weight = Int8Params(
            weight.data,
            has_fp16_weights=has_fp16_weights,
            requires_grad=has_fp16_weights,
197
        )
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
        self.weight.cuda(weight.device)
        self.bias = bias

    def init_8bit_state(self):
        self.state.CB = self.weight.CB
        self.state.SCB = self.weight.SCB
        self.weight.CB = None
        self.weight.SCB = None

    def forward(self, x: torch.Tensor):
        self.state.is_training = self.training
        if self.weight.CB is not None:
            self.init_8bit_state()

        # weights are cast automatically as Int8Params, but the bias has to be cast manually
        if self.bias is not None and self.bias.dtype != x.dtype:
            self.bias.data = self.bias.data.to(x.dtype)

        out = bnb.matmul(x, self.weight, bias=self.bias, state=self.state)

        if not self.state.has_fp16_weights:
            if self.state.CB is not None and self.state.CxB is not None:
                # we converted 8-bit row major to turing/ampere format in the first inference pass
                # we no longer need the row-major weight
                del self.state.CB
                self.weight.data = self.state.CxB
        return out
225
226


Nicolas Patry's avatar
Nicolas Patry committed
227
228
229
230
class Linear4bit(nn.Module):
    def __init__(self, weight, bias, quant_type):
        super().__init__()
        self.weight = Params4bit(
OlivierDehaene's avatar
OlivierDehaene committed
231
232
233
234
            weight.data,
            requires_grad=False,
            compress_statistics=True,
            quant_type=quant_type,
Nicolas Patry's avatar
Nicolas Patry committed
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
        )
        self.compute_dtype = None
        self.weight.cuda(weight.device)
        self.bias = bias

    def forward(self, x: torch.Tensor):
        # weights are cast automatically as Int8Params, but the bias has to be cast manually
        if self.bias is not None and self.bias.dtype != x.dtype:
            self.bias.data = self.bias.data.to(x.dtype)

        if getattr(self.weight, "quant_state", None) is None:
            print(
                "FP4 quantization state not initialized. Please call .cuda() or .to(device) on the LinearFP4 layer first."
            )
        inp_dtype = x.dtype
        if self.compute_dtype is not None:
            x = x.to(self.compute_dtype)

        bias = None if self.bias is None else self.bias.to(self.compute_dtype)
        out = bnb.matmul_4bit(
            x, self.weight.t(), bias=bias, quant_state=self.weight.quant_state
        )

        out = out.to(inp_dtype)

        return out


263
264
@lru_cache(1)
def warn_deprecate_bnb():
OlivierDehaene's avatar
OlivierDehaene committed
265
266
267
268
    logger.warning(
        "Bitsandbytes 8bit is deprecated, using `eetq` is a drop-in replacement, and has much better performnce"
    )

269

270
271
272
def get_linear(weight, bias, quantize):
    if quantize is None:
        linear = FastLinear(weight, bias)
273
274
275
276
    elif quantize == "eetq":
        if HAS_EETQ:
            linear = EETQLinear(weight, bias)
        else:
OlivierDehaene's avatar
OlivierDehaene committed
277
278
279
            raise ImportError(
                "Please install EETQ from https://github.com/NetEase-FuXi/EETQ"
            )
280
    elif quantize == "bitsandbytes":
281
        warn_deprecate_bnb()
282
283
284
285
286
287
288
289
        linear = Linear8bitLt(
            weight,
            bias,
            has_fp16_weights=False,
            threshold=6.0,
        )
        if bias is not None:
            linear.bias = nn.Parameter(bias)
Nicolas Patry's avatar
Nicolas Patry committed
290
291
292
293
294
295
296
297
298
299
300
301
    elif quantize == "bitsandbytes-fp4":
        linear = Linear4bit(
            weight,
            bias,
            quant_type="fp4",
        )
    elif quantize == "bitsandbytes-nf4":
        linear = Linear4bit(
            weight,
            bias,
            quant_type="nf4",
        )
302
    elif quantize == "gptq":
303
        try:
304
            qweight, qzeros, scales, g_idx, bits, groupsize, use_exllama = weight
305
306
307
308
309
        except Exception:
            raise NotImplementedError(
                f"The passed weight is not `gptq` compatible, loader needs to be updated."
            )

310
311
312
313
314
315
316
317
318
319
320
321
        if use_exllama:
            linear = Ex4bitLinear(qweight, qzeros, scales, g_idx, bias, bits, groupsize)
        else:
            linear = QuantLinear(
                qweight,
                qzeros,
                scales,
                g_idx,
                bias,
                bits,
                groupsize,
            )
322
323
324
325
326
327
328
    elif quantize == "awq":
        try:
            qweight, qzeros, scales, _, bits, groupsize, _ = weight
        except Exception:
            raise NotImplementedError(
                f"The passed weight is not `awq` compatible, loader needs to be updated."
            )
OlivierDehaene's avatar
OlivierDehaene committed
329
330
331
332
333
334
335
336
        linear = WQLinear(
            w_bit=bits,
            group_size=groupsize,
            qweight=qweight,
            qzeros=qzeros,
            scales=scales,
            bias=bias is not None,
        )
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
    else:
        raise NotImplementedError(f"Quantization `{quantize}` is not implemented yet.")
    return linear


class SuperLayer(nn.Module):
    def __init__(self, linear):
        super().__init__()
        self.linear = linear

    def forward(self, x):
        return self.linear.forward(x)


class TensorParallelHead(SuperLayer):
352
    def __init__(self, linear, process_group, should_gather: bool):
353
        super().__init__(linear)
354
        self.process_group = process_group
355
        self.should_gather = should_gather
356
357
358

    @staticmethod
    def load(config, prefix: str, weights):
359
360
361
362
363
364
365
366
367
368
369
370
        if weights.process_group.size() > 1:
            try:
                weight = weights.get_sharded(f"{prefix}.weight", dim=0)
                should_gather = True
            except AssertionError:
                # If the vocab size is not divisible by number of shards
                # just load the entire thing.
                weight = weights.get_tensor(f"{prefix}.weight")
                should_gather = False
        else:
            weight = weights.get_tensor(f"{prefix}.weight")
            should_gather = False
371

372
373
        # GPTQ,AWQ,EETQ don't quantize heads (nor embeddings)
        if config.quantize in ["gptq", "awq", "eetq"]:
374
375
376
            quantize = None
        else:
            quantize = config.quantize
377
        return TensorParallelHead(
378
            get_linear(weight, bias=None, quantize=quantize),
379
            process_group=weights.process_group,
380
            should_gather=should_gather,
381
382
383
        )

    def forward(self, input: torch.Tensor) -> torch.Tensor:
OlivierDehaene's avatar
OlivierDehaene committed
384
385
386
        if not self.should_gather:
            return super().forward(input)

387
        world_size = self.process_group.size()
OlivierDehaene's avatar
OlivierDehaene committed
388
        if len(input.shape) == 2 and isinstance(self.linear, FastLinear):
389
390
            out_dim = self.linear.weight.shape[0]

OlivierDehaene's avatar
OlivierDehaene committed
391
392
393
394
395
396
397
398
            if input.shape[0] == 1:
                world_out = input.new_empty(1, out_dim * world_size)
                local_out = input.new_empty(1, out_dim)
                gather_input = local_out
            else:
                world_out = input.new_empty(out_dim * world_size, input.shape[0])
                gather_input = input.new_empty(out_dim, input.shape[0])
                local_out = gather_input.T
399
400
401
402

            torch.mm(input, self.linear.weight.T, out=local_out)

            torch.distributed.all_gather_into_tensor(
OlivierDehaene's avatar
OlivierDehaene committed
403
                world_out, gather_input, group=self.process_group
404
405
            )

OlivierDehaene's avatar
OlivierDehaene committed
406
407
408
            if input.shape[0] == 1:
                return world_out
            return world_out.T
409

OlivierDehaene's avatar
OlivierDehaene committed
410
411
412
413
        output = super().forward(input)
        world_output = [
            torch.empty_like(output) for _ in range(self.process_group.size())
        ]
414
415
416
417
418
419
420
        torch.distributed.all_gather(world_output, output, group=self.process_group)
        world_output = torch.cat(world_output, dim=-1)
        return world_output


class TensorParallelColumnLinear(SuperLayer):
    @classmethod
xiaobin's avatar
xiaobin committed
421
422
    def load_qkv(cls, config, prefix: str, weights, bias: bool):
        """Specific method when the QKV was joined after the fact"""
OlivierDehaene's avatar
OlivierDehaene committed
423
        weight = weights.get_weights_col_packed_qkv(prefix, quantize=config.quantize)
xiaobin's avatar
xiaobin committed
424
425
426
427
428
429
430
431
        if bias:
            raise NotImplementedError("packed_qkv only implemented for baichuan")
        else:
            bias = None
        linear = get_linear(weight, bias, config.quantize)
        return cls(linear)

    @classmethod
432
    def load(cls, config, prefix: str, weights, bias: bool):
433
        return cls.load_multi(config, [prefix], weights, bias, dim=0)
434

435
436
    @classmethod
    def load_multi(cls, config, prefixes: List[str], weights, bias: bool, dim: int):
437
438
439
        weight = weights.get_multi_weights_col(
            prefixes, quantize=config.quantize, dim=dim
        )
440

441
442
        if bias:
            b = [weights.get_sharded(f"{p}.bias", dim=0) for p in prefixes]
443
            bias = torch.cat(b, dim=dim)
444
445
        else:
            bias = None
446
447
        linear = get_linear(weight, bias, config.quantize)
        return cls(linear)
448

449
450
451
452

class TensorParallelRowLinear(SuperLayer):
    def __init__(self, linear, process_group):
        super().__init__(linear)
453
454
        self.process_group = process_group

455
456
    @classmethod
    def load(cls, config, prefix: str, weights, bias: bool):
457
458
        weight = weights.get_multi_weights_row(prefix, quantize=config.quantize)

459
460
461
462
463
464
465
466
467
        if bias and weights.process_group.rank() == 0:
            # Rank is only on the first rank process
            bias = weights.get_tensor(f"{prefix}.bias")
        else:
            bias = None
        return cls(
            get_linear(weight, bias, config.quantize),
            process_group=weights.process_group,
        )
468

469
470
    def forward(self, input: torch.Tensor) -> torch.Tensor:
        out = super().forward(input)
471
472
        if self.process_group.size() > 1:
            torch.distributed.all_reduce(out, group=self.process_group)
473
        return out
474
475


476
477
478
class TensorParallelEmbedding(nn.Module):
    def __init__(self, prefix: str, weights, reduce=True):
        super().__init__()
479
        weight = weights.get_partial_sharded(f"{prefix}.weight", dim=0)
480
481
482
483
484
485
486
487
488
489
490
491
492
        num_embeddings = weights.get_shape(f"{prefix}.weight")[0]

        process_group = weights.process_group

        world_size = process_group.size()
        rank = process_group.rank()

        block_size = num_embeddings // world_size
        self.min_id = rank * block_size
        self.max_id = min(num_embeddings, (rank + 1) * block_size)
        self.null_idx = block_size
        self.process_group = weights.process_group
        self.reduce = reduce
493
494

        """Additional 0 entry used for masking"""
495
        self.weight = nn.Parameter(F.pad(weight, (0, 0, 0, 1)))
496
497
498
499
500
501
502
503
504

    def forward(self, input: torch.Tensor) -> torch.Tensor:
        # default all out of bounds values to `self.null_idx` that will then be mapped to 0
        # translate for [0, self.max_id - self.min_id[
        input = torch.where(
            (self.min_id > input) | (input >= self.max_id),
            self.null_idx,
            input - self.min_id,
        )
505
        out = torch.nn.functional.embedding(input, self.weight)
506
        if self.reduce and self.process_group.size() > 1:
507
            torch.distributed.all_reduce(out, group=self.process_group)
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
554
555
556
        return out


try:
    import dropout_layer_norm

    class FastLayerNorm(nn.LayerNorm):
        def forward(self, hidden_states, residual=None):
            if hidden_states.shape[-1] > 8192:
                if residual is not None:
                    hidden_states += residual
                residual = hidden_states

                return super(FastLayerNorm, self).forward(hidden_states), residual
            else:
                (
                    normed_hidden_states,
                    residual,
                    *rest,
                ) = dropout_layer_norm.dropout_add_ln_fwd(
                    hidden_states,
                    residual,
                    self.weight,
                    self.bias,
                    None,
                    None,
                    None,
                    None,
                    0.0,
                    self.eps,
                    1.0,
                    0,
                    None,
                    False,
                    False,
                )
                if residual is None:
                    residual = hidden_states

                return normed_hidden_states, residual

except ImportError:
    pass


try:
    from flash_attn.layers.rotary import RotaryEmbedding
    import rotary_emb

Nicolas Patry's avatar
Nicolas Patry committed
557
558
    def _create_inv_freq(dim, base, device):
        inv_freq = 1.0 / (
OlivierDehaene's avatar
OlivierDehaene committed
559
            base ** (torch.arange(0, dim, 2, device=device, dtype=torch.float32) / dim)
Nicolas Patry's avatar
Nicolas Patry committed
560
561
562
563
564
        )
        return inv_freq

    def _get_rope_config(config):
        if os.getenv("ROPE_SCALING", None) is not None:
OlivierDehaene's avatar
OlivierDehaene committed
565
566
567
568
            rope_scaling = {
                "type": os.environ["ROPE_SCALING"],
                "factor": float(os.environ["ROPE_FACTOR"]),
            }
Nicolas Patry's avatar
Nicolas Patry committed
569
570
571
            return rope_scaling
        return getattr(config, "rope_scaling", None)

572
    class PositionRotaryEmbedding(nn.Module):
Nicolas Patry's avatar
Nicolas Patry committed
573
        def __init__(self, inv_freq, scaling_factor):
574
            super().__init__()
575
            self.inv_freq = inv_freq
576
577
578
579
580
            self._seq_len_cached = 0
            self._cos_cached = None
            self._sin_cached = None
            self._cos_k_cached = None
            self._sin_k_cached = None
Nicolas Patry's avatar
Nicolas Patry committed
581
582
            self.scaling_factor = scaling_factor
            self.dynamic_args = None
583
584

        @classmethod
Nicolas Patry's avatar
Nicolas Patry committed
585
586
587
588
589
590
591
592
593
        def static(cls, config, dim, base, device):
            inv_freq = _create_inv_freq(dim, base, device)
            scaling_factor = None
            rope_scaling = _get_rope_config(config)
            if rope_scaling is not None:
                scaling_factor = rope_scaling["factor"]
                if rope_scaling["type"] == "linear":
                    pass
                elif rope_scaling["type"] == "dynamic":
OlivierDehaene's avatar
OlivierDehaene committed
594
595
596
597
598
599
600
                    return DynamicPositionRotaryEmbedding(
                        dim=dim,
                        max_position_embeddings=config.max_position_embeddings,
                        base=base,
                        device=inv_freq.device,
                        scaling_factor=scaling_factor,
                    )
Nicolas Patry's avatar
Nicolas Patry committed
601
602
603
604
605
606
607
608
609
610
611
612
613
                elif rope_scaling["type"] == "yarn":
                    return YarnPositionRotaryEmbedding(
                        dim=2 * inv_freq.shape[0],
                        max_position_embeddings=rope_scaling["original_max_position_embeddings"],
                        base=10000.0,
                        device=inv_freq.device,
                        scaling_factor=scaling_factor,
                        extrapolation_factor=1,
                        attn_factor=1,
                        beta_fast=32,
                        beta_slow=1

                    )
Nicolas Patry's avatar
Nicolas Patry committed
614
                else:
OlivierDehaene's avatar
OlivierDehaene committed
615
616
617
                    raise NotImplementedError(
                        f"rope scaling type {rope_scaling['type']} is not implemented or invalid"
                    )
Nicolas Patry's avatar
Nicolas Patry committed
618
            return cls(inv_freq, scaling_factor)
619
620

        @classmethod
Nicolas Patry's avatar
Nicolas Patry committed
621
        def load(cls, config, prefix, weights):
622
623
624
625
626
            # XXX: Always load this in float32 !
            dtype = weights.dtype
            weights.dtype = torch.float32
            inv_freq = weights.get_tensor(f"{prefix}.inv_freq")
            weights.dtype = dtype
Nicolas Patry's avatar
Nicolas Patry committed
627
628
629
630
631
632
633
634

            scaling_factor = None
            rope_scaling = _get_rope_config(config)
            if rope_scaling is not None:
                scaling_factor = rope_scaling["factor"]
                if rope_scaling["type"] == "linear":
                    pass
                elif rope_scaling["type"] == "dynamic":
OlivierDehaene's avatar
OlivierDehaene committed
635
636
637
638
639
640
641
                    return DynamicPositionRotaryEmbedding(
                        dim=2 * inv_freq.shape[0],
                        max_position_embeddings=config.max_position_embeddings,
                        base=10000.0,
                        device=inv_freq.device,
                        scaling_factor=scaling_factor,
                    )
Nicolas Patry's avatar
Nicolas Patry committed
642
643
644
645
646
647
648
649
650
651
652
653
654
                elif rope_scaling["type"] == "yarn":
                    return YarnPositionRotaryEmbedding(
                        dim=2 * inv_freq.shape[0],
                        max_position_embeddings=rope_scaling["original_max_position_embeddings"],
                        base=10000.0,
                        device=inv_freq.device,
                        scaling_factor=scaling_factor,
                        extrapolation_factor=1,
                        attn_factor=1,
                        beta_fast=32,
                        beta_slow=1

                    )
Nicolas Patry's avatar
Nicolas Patry committed
655
                else:
OlivierDehaene's avatar
OlivierDehaene committed
656
657
658
                    raise NotImplementedError(
                        f"rope scaling type {rope_scaling['type']} is not implemented or invalid"
                    )
Nicolas Patry's avatar
Nicolas Patry committed
659
            return cls(inv_freq, scaling_factor)
660

661
662
663
664
665
666
667
668
669
670
        def _update_cos_sin_cache(self, dtype, device, seqlen):
            # Reset the tables if the sequence length has changed,
            # or if we're on a new device (possibly due to tracing for instance)
            if (
                seqlen > self._seq_len_cached
                or self._cos_cached.device != device
                or self._cos_cached.dtype != dtype
            ):
                self._seq_len_cached = seqlen
                t = torch.arange(seqlen, device=device, dtype=self.inv_freq.dtype)
Nicolas Patry's avatar
Nicolas Patry committed
671
672
                if self.scaling_factor is not None:
                    t /= self.scaling_factor
673
674
                # Don't do einsum, it converts fp32 to fp16
                # freqs = torch.einsum("i,j->ij", t, self.inv_freq)
Nicolas Patry's avatar
Nicolas Patry committed
675

676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
                freqs = torch.outer(t, self.inv_freq.to(device=t.device))
                self._cos_cached = torch.cos(freqs).to(dtype)
                self._sin_cached = torch.sin(freqs).to(dtype)

        def get_cos_sin(
            self, position_ids: torch.Tensor, max_s: int, dtype: torch.dtype
        ):
            """
            Return cos and sin for the asked position ids
            """

            self._update_cos_sin_cache(dtype, position_ids.device, max_s)

            cos = torch.index_select(self._cos_cached, 0, position_ids)
            sin = torch.index_select(self._sin_cached, 0, position_ids)
            return cos.unsqueeze(1), sin.unsqueeze(1)

693
        def forward(self, x: torch.Tensor, cos: torch.Tensor, sin: torch.Tensor):
694
            rotary_dim = cos.shape[-1]
695
696
697
698
699
            x1 = x[..., :rotary_dim]
            x2 = x[..., rotary_dim : 2 * rotary_dim]

            rotary_emb.apply_rotary(x1, x2, cos, sin, x1, x2, False)
            return x
700

Nicolas Patry's avatar
Nicolas Patry committed
701
702
    class DynamicPositionRotaryEmbedding(PositionRotaryEmbedding):
        def __init__(self, dim, max_position_embeddings, base, device, scaling_factor):
Nicolas Patry's avatar
Nicolas Patry committed
703
            inv_freq = _create_inv_freq(dim, base, device)
Nicolas Patry's avatar
Nicolas Patry committed
704
705
706
707
708
709
710
711
712
713
714
715
716
717
            super().__init__(inv_freq, scaling_factor)
            self.dim = dim
            self.max_position_embeddings = max_position_embeddings
            self.base = base

        def _update_cos_sin_cache(self, dtype, device, seqlen):
            # Reset the tables if the sequence length has changed,
            # or if we're on a new device (possibly due to tracing for instance)
            if (
                seqlen > self._seq_len_cached
                or self._cos_cached.device != device
                or self._cos_cached.dtype != dtype
            ):
                if seqlen > self.max_position_embeddings:
OlivierDehaene's avatar
OlivierDehaene committed
718
719
720
721
722
723
724
                    newbase = self.base * (
                        (self.scaling_factor * seqlen / self.max_position_embeddings)
                        - (self.scaling_factor - 1)
                    ) ** (self.dim / (self.dim - 2))
                    self.inv_freq = _create_inv_freq(
                        self.dim, newbase, self.inv_freq.device
                    )
Nicolas Patry's avatar
Nicolas Patry committed
725
726
727
728
729
730
731
732
733
                self._seq_len_cached = seqlen
                t = torch.arange(seqlen, device=device, dtype=self.inv_freq.dtype)
                # Don't do einsum, it converts fp32 to fp16
                # freqs = torch.einsum("i,j->ij", t, self.inv_freq)

                freqs = torch.outer(t, self.inv_freq.to(device=t.device))
                self._cos_cached = torch.cos(freqs).to(dtype)
                self._sin_cached = torch.sin(freqs).to(dtype)

Nicolas Patry's avatar
Nicolas Patry committed
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804

    # Inverse dim formula to find dim based on number of rotations
    import math
    def find_correction_dim(num_rotations, dim, base=10000, max_position_embeddings=2048):
        return (dim * math.log(max_position_embeddings/(num_rotations * 2 * math.pi)))/(2 * math.log(base))

    # Find dim range bounds based on rotations
    def find_correction_range(low_rot, high_rot, dim, base=10000, max_position_embeddings=2048):
        low = math.floor(find_correction_dim(
            low_rot, dim, base, max_position_embeddings))
        high = math.ceil(find_correction_dim(
            high_rot, dim, base, max_position_embeddings))
        return max(low, 0), min(high, dim-1)  # Clamp values just in case

    def linear_ramp_mask(min, max, dim):
        if min == max:
            max += 0.001  # Prevent singularity

        linear_func = (torch.arange(dim, dtype=torch.float32) - min) / (max - min)
        ramp_func = torch.clamp(linear_func, 0, 1)
        return ramp_func

    def get_mscale(scale=1):
        if scale <= 1:
            return 1.0
        return 0.1 * math.log(scale) + 1.0

    class YarnPositionRotaryEmbedding(PositionRotaryEmbedding):
        def __init__(self, dim, max_position_embeddings, base, device, scaling_factor,*, extrapolation_factor, attn_factor, beta_fast, beta_slow):
            inv_freq = _create_inv_freq(dim, base, device)
            super().__init__(inv_freq, scaling_factor)
            self.dim = dim
            self.max_position_embeddings = max_position_embeddings
            self.base = base
            self.extrapolation_factor = extrapolation_factor
            self.attn_factor = attn_factor
            self.beta_fast = beta_fast
            self.beta_slow = beta_slow
            self.mscale = float(get_mscale(self.scaling_factor) * self.attn_factor) # Get n-d magnitude scaling corrected for interpolation

        def _update_cos_sin_cache(self, dtype, device, seqlen):
            # Reset the tables if the sequence length has changed,
            # or if we're on a new device (possibly due to tracing for instance)
            if (
                seqlen > self._seq_len_cached
                or self._cos_cached.device != device
                or self._cos_cached.dtype != dtype
            ):
                if seqlen > self.max_position_embeddings:
                    inv_freq_extrapolation = _create_inv_freq(
                        self.dim, self.base, self.inv_freq.device
                    )
                    freqs = 1.0 / inv_freq_extrapolation
                    inv_freq_interpolation = 1.0 / (self.scaling_factor * freqs)
                    low, high = find_correction_range(self.beta_fast, self.beta_slow, self.dim, self.base, self.max_position_embeddings)
                    inv_freq_mask = (1 - linear_ramp_mask(low, high, self.dim // 2).float().to(device)) * self.extrapolation_factor # Get n-d rotational scaling corrected for extrapolation
                    inv_freq = inv_freq_interpolation * (1 - inv_freq_mask) + inv_freq_extrapolation * inv_freq_mask

                    self.inv_freq = inv_freq
                    self.mscale = float(get_mscale(self.scaling_factor) * self.attn_factor) # Get n-d magnitude scaling corrected for interpolation


                self._seq_len_cached = seqlen
                t = torch.arange(seqlen, device=device, dtype=self.inv_freq.dtype)
                # Don't do einsum, it converts fp32 to fp16
                # freqs = torch.einsum("i,j->ij", t, self.inv_freq)

                freqs = torch.outer(t, self.inv_freq.to(device=t.device))
                self._cos_cached = (torch.cos(freqs) * self.mscale).to(dtype)
                self._sin_cached = (torch.sin(freqs) * self.mscale).to(dtype)

805
806
except ImportError:
    pass