|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
""" PyTorch Jamba model.""" |
|
import inspect |
|
import math |
|
import warnings |
|
from dataclasses import dataclass, field |
|
from typing import Any, Dict, List, Optional, Tuple, Union |
|
|
|
import torch |
|
import torch.nn.functional as F |
|
import torch.utils.checkpoint |
|
from torch import nn |
|
from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss |
|
|
|
from transformers.activations import ACT2FN |
|
from transformers.cache_utils import Cache, DynamicCache |
|
from transformers.modeling_attn_mask_utils import ( |
|
_prepare_4d_causal_attention_mask, |
|
_prepare_4d_causal_attention_mask_for_sdpa, |
|
) |
|
from transformers.modeling_outputs import ( |
|
MoeCausalLMOutputWithPast, |
|
MoeModelOutputWithPast, |
|
SequenceClassifierOutputWithPast, |
|
) |
|
from transformers.modeling_utils import PreTrainedModel |
|
from transformers.pytorch_utils import is_torch_greater_or_equal_than_1_13 |
|
from transformers.utils import ( |
|
add_start_docstrings, |
|
add_start_docstrings_to_model_forward, |
|
is_flash_attn_greater_or_equal_2_10, |
|
logging, |
|
replace_return_docstrings, |
|
) |
|
from transformers.utils.import_utils import is_torch_fx_available |
|
from .configuration_jamba import JambaConfig |
|
|
|
|
|
|
|
try: |
|
from flash_attn import flash_attn_func, flash_attn_varlen_func |
|
from flash_attn.bert_padding import index_first_axis, pad_input, unpad_input |
|
|
|
_flash_supports_window_size = "window_size" in list(inspect.signature(flash_attn_func).parameters) |
|
except ImportError: |
|
pass |
|
|
|
|
|
|
|
if is_torch_fx_available(): |
|
if not is_torch_greater_or_equal_than_1_13: |
|
import torch.fx |
|
|
|
_prepare_4d_causal_attention_mask = torch.fx.wrap(_prepare_4d_causal_attention_mask) |
|
|
|
|
|
try: |
|
from mamba_ssm.ops.selective_scan_interface import mamba_inner_fn, selective_scan_fn |
|
from mamba_ssm.ops.triton.selective_state_update import selective_state_update |
|
except ImportError: |
|
selective_state_update, selective_scan_fn, mamba_inner_fn = None, None, None |
|
|
|
|
|
try: |
|
from causal_conv1d import causal_conv1d_fn, causal_conv1d_update |
|
except ImportError: |
|
causal_conv1d_update, causal_conv1d_fn = None, None |
|
|
|
is_fast_path_available = all( |
|
(selective_state_update, selective_scan_fn, causal_conv1d_fn, causal_conv1d_update, mamba_inner_fn) |
|
) |
|
|
|
|
|
logger = logging.get_logger(__name__) |
|
|
|
_CONFIG_FOR_DOC = "JambaConfig" |
|
|
|
|
|
|
|
def load_balancing_loss_func( |
|
gate_logits: torch.Tensor, num_experts: torch.Tensor = None, top_k=2, attention_mask: Optional[torch.Tensor] = None |
|
) -> float: |
|
r""" |
|
Computes auxiliary load balancing loss as in Switch Transformer - implemented in Pytorch. |
|
|
|
See Switch Transformer (https://arxiv.org/abs/2101.03961) for more details. This function implements the loss |
|
function presented in equations (4) - (6) of the paper. It aims at penalizing cases where the routing between |
|
experts is too unbalanced. |
|
|
|
Args: |
|
gate_logits (Union[`torch.Tensor`, Tuple[torch.Tensor]): |
|
Logits from the `router`, should be a tuple of model.config.num_hidden_layers tensors of |
|
shape [batch_size X sequence_length, num_experts]. |
|
attention_mask (`torch.Tensor`, None): |
|
The attention_mask used in forward function |
|
shape [batch_size X sequence_length] if not None. |
|
num_experts (`int`, *optional*): |
|
Number of experts |
|
|
|
Returns: |
|
The auxiliary loss. |
|
""" |
|
if gate_logits is None or not isinstance(gate_logits, tuple): |
|
return 0 |
|
|
|
if isinstance(gate_logits, tuple): |
|
compute_device = gate_logits[0].device |
|
concatenated_gate_logits = torch.cat( |
|
[layer_gate.to(compute_device) for layer_gate in gate_logits if layer_gate.shape[1] > 1], dim=0 |
|
) |
|
|
|
routing_weights = torch.nn.functional.softmax(concatenated_gate_logits, dim=-1) |
|
|
|
_, selected_experts = torch.topk(routing_weights, top_k, dim=-1) |
|
|
|
expert_mask = torch.nn.functional.one_hot(selected_experts, num_experts) |
|
|
|
if attention_mask is None: |
|
|
|
tokens_per_expert = torch.mean(expert_mask.float(), dim=0) |
|
|
|
|
|
router_prob_per_expert = torch.mean(routing_weights, dim=0) |
|
else: |
|
batch_size, sequence_length = attention_mask.shape |
|
num_hidden_layers = concatenated_gate_logits.shape[0] // (batch_size * sequence_length) |
|
|
|
|
|
expert_attention_mask = ( |
|
attention_mask[None, :, :, None, None] |
|
.expand((num_hidden_layers, batch_size, sequence_length, top_k, num_experts)) |
|
.reshape(-1, top_k, num_experts) |
|
.to(compute_device) |
|
) |
|
|
|
|
|
tokens_per_expert = torch.sum(expert_mask.float() * expert_attention_mask, dim=0) / torch.sum( |
|
expert_attention_mask, dim=0 |
|
) |
|
|
|
|
|
router_per_expert_attention_mask = ( |
|
attention_mask[None, :, :, None] |
|
.expand((num_hidden_layers, batch_size, sequence_length, num_experts)) |
|
.reshape(-1, num_experts) |
|
.to(compute_device) |
|
) |
|
|
|
|
|
router_prob_per_expert = torch.sum(routing_weights * router_per_expert_attention_mask, dim=0) / torch.sum( |
|
router_per_expert_attention_mask, dim=0 |
|
) |
|
|
|
overall_loss = torch.sum(tokens_per_expert * router_prob_per_expert.unsqueeze(0)) |
|
return overall_loss * num_experts |
|
|
|
|
|
|
|
def _get_unpad_data(attention_mask): |
|
seqlens_in_batch = attention_mask.sum(dim=-1, dtype=torch.int32) |
|
indices = torch.nonzero(attention_mask.flatten(), as_tuple=False).flatten() |
|
max_seqlen_in_batch = seqlens_in_batch.max().item() |
|
cu_seqlens = F.pad(torch.cumsum(seqlens_in_batch, dim=0, dtype=torch.int32), (1, 0)) |
|
return ( |
|
indices, |
|
cu_seqlens, |
|
max_seqlen_in_batch, |
|
) |
|
|
|
|
|
|
|
class JambaRMSNorm(nn.Module): |
|
def __init__(self, hidden_size, eps=1e-6): |
|
""" |
|
JambaRMSNorm is equivalent to T5LayerNorm |
|
""" |
|
super().__init__() |
|
self.weight = nn.Parameter(torch.ones(hidden_size)) |
|
self.variance_epsilon = eps |
|
|
|
def forward(self, hidden_states): |
|
input_dtype = hidden_states.dtype |
|
hidden_states = hidden_states.to(torch.float32) |
|
variance = hidden_states.pow(2).mean(-1, keepdim=True) |
|
hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon) |
|
return self.weight * hidden_states.to(input_dtype) |
|
|
|
|
|
|
|
def repeat_kv(hidden_states: torch.Tensor, n_rep: int) -> torch.Tensor: |
|
""" |
|
This is the equivalent of torch.repeat_interleave(x, dim=1, repeats=n_rep). The hidden states go from (batch, |
|
num_key_value_heads, seqlen, head_dim) to (batch, num_attention_heads, seqlen, head_dim) |
|
""" |
|
batch, num_key_value_heads, slen, head_dim = hidden_states.shape |
|
if n_rep == 1: |
|
return hidden_states |
|
hidden_states = hidden_states[:, :, None, :, :].expand(batch, num_key_value_heads, n_rep, slen, head_dim) |
|
return hidden_states.reshape(batch, num_key_value_heads * n_rep, slen, head_dim) |
|
|
|
|
|
|
|
class JambaAttention(nn.Module): |
|
""" |
|
Multi-headed attention from 'Attention Is All You Need' paper. Modified to use sliding window attention: Longformer |
|
and "Generating Long Sequences with Sparse Transformers". |
|
""" |
|
|
|
def __init__(self, config: JambaConfig, layer_idx: Optional[int] = None): |
|
super().__init__() |
|
self.config = config |
|
self.layer_idx = layer_idx |
|
if layer_idx is None: |
|
logger.warning_once( |
|
f"Instantiating {self.__class__.__name__} without passing a `layer_idx` is not recommended and will " |
|
"lead to errors during the forward call if caching is used. Please make sure to provide a `layer_idx` " |
|
"when creating this class." |
|
) |
|
|
|
self.hidden_size = config.hidden_size |
|
self.num_heads = config.num_attention_heads |
|
self.head_dim = self.hidden_size // self.num_heads |
|
self.num_key_value_heads = config.num_key_value_heads |
|
self.num_key_value_groups = self.num_heads // self.num_key_value_heads |
|
self.is_causal = True |
|
self.attention_dropout = config.attention_dropout |
|
|
|
if (self.head_dim * self.num_heads) != self.hidden_size: |
|
raise ValueError( |
|
f"hidden_size must be divisible by num_heads (got `hidden_size`: {self.hidden_size}" |
|
f" and `num_heads`: {self.num_heads})." |
|
) |
|
self.q_proj = nn.Linear(self.hidden_size, self.num_heads * self.head_dim, bias=False) |
|
self.k_proj = nn.Linear(self.hidden_size, self.num_key_value_heads * self.head_dim, bias=False) |
|
self.v_proj = nn.Linear(self.hidden_size, self.num_key_value_heads * self.head_dim, bias=False) |
|
self.o_proj = nn.Linear(self.num_heads * self.head_dim, self.hidden_size, bias=False) |
|
|
|
def _shape(self, tensor: torch.Tensor, seq_len: int, bsz: int): |
|
return tensor.view(bsz, seq_len, self.num_heads, self.head_dim).transpose(1, 2).contiguous() |
|
|
|
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, |
|
**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() |
|
|
|
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) |
|
|
|
kv_seq_len = key_states.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) |
|
|
|
if past_key_value is not None: |
|
key_states, value_states = past_key_value.update(key_states, value_states, self.layer_idx) |
|
|
|
|
|
key_states = repeat_kv(key_states, self.num_key_value_groups) |
|
value_states = repeat_kv(value_states, self.num_key_value_groups) |
|
|
|
attn_weights = torch.matmul(query_states, key_states.transpose(2, 3)) / math.sqrt(self.head_dim) |
|
|
|
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()}" |
|
) |
|
|
|
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()}" |
|
) |
|
|
|
attn_weights = attn_weights + attention_mask |
|
|
|
|
|
attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query_states.dtype) |
|
attn_weights = nn.functional.dropout(attn_weights, p=self.attention_dropout, training=self.training) |
|
attn_output = torch.matmul(attn_weights, value_states) |
|
|
|
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, self.hidden_size) |
|
|
|
attn_output = self.o_proj(attn_output) |
|
|
|
if not output_attentions: |
|
attn_weights = None |
|
|
|
return attn_output, attn_weights, past_key_value |
|
|
|
|
|
|
|
class JambaFlashAttention2(JambaAttention): |
|
""" |
|
Jamba flash attention module. This module inherits from `JambaAttention` as the weights of the module stays |
|
untouched. The only required change would be on the forward pass where it needs to correctly call the public API of |
|
flash attention and deal with padding tokens in case the input contains any of them. |
|
""" |
|
|
|
|
|
def __init__(self, *args, **kwargs): |
|
super().__init__(*args, **kwargs) |
|
|
|
|
|
|
|
|
|
self._flash_attn_uses_top_left_mask = not is_flash_attn_greater_or_equal_2_10() |
|
|
|
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, |
|
**kwargs, |
|
): |
|
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.`" |
|
) |
|
|
|
|
|
attention_mask = kwargs.pop("padding_mask") |
|
bsz, q_len, _ = hidden_states.size() |
|
|
|
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) |
|
|
|
kv_seq_len = key_states.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) |
|
|
|
use_sliding_windows = ( |
|
_flash_supports_window_size |
|
and getattr(self.config, "sliding_window", None) is not None |
|
and kv_seq_len > self.config.sliding_window |
|
) |
|
|
|
if not _flash_supports_window_size: |
|
logger.warning_once( |
|
"The current flash attention version does not support sliding window attention, for a more memory efficient implementation" |
|
" make sure to upgrade flash-attn library." |
|
) |
|
|
|
if past_key_value is not None: |
|
|
|
cache_has_contents = past_key_value.get_seq_length(self.layer_idx) > 0 |
|
if ( |
|
getattr(self.config, "sliding_window", None) is not None |
|
and kv_seq_len > self.config.sliding_window |
|
and cache_has_contents |
|
): |
|
slicing_tokens = 1 - self.config.sliding_window |
|
|
|
past_key = past_key_value[self.layer_idx][0] |
|
past_value = past_key_value[self.layer_idx][1] |
|
|
|
past_key = past_key[:, :, slicing_tokens:, :].contiguous() |
|
past_value = past_value[:, :, slicing_tokens:, :].contiguous() |
|
|
|
if past_key.shape[-2] != self.config.sliding_window - 1: |
|
raise ValueError( |
|
f"past key must have a shape of (`batch_size, num_heads, self.config.sliding_window-1, head_dim`), got" |
|
f" {past_key.shape}" |
|
) |
|
|
|
if attention_mask is not None: |
|
attention_mask = attention_mask[:, slicing_tokens:] |
|
attention_mask = torch.cat([attention_mask, torch.ones_like(attention_mask[:, -1:])], dim=-1) |
|
|
|
key_states, value_states = past_key_value.update(key_states, value_states, self.layer_idx) |
|
|
|
|
|
key_states = repeat_kv(key_states, self.num_key_value_groups) |
|
value_states = repeat_kv(value_states, self.num_key_value_groups) |
|
dropout_rate = 0.0 if not self.training else self.attention_dropout |
|
|
|
|
|
|
|
|
|
input_dtype = query_states.dtype |
|
if input_dtype == torch.float32: |
|
if torch.is_autocast_enabled(): |
|
target_dtype = torch.get_autocast_gpu_dtype() |
|
|
|
elif hasattr(self.config, "_pre_quantization_dtype"): |
|
target_dtype = self.config._pre_quantization_dtype |
|
else: |
|
target_dtype = self.q_proj.weight.dtype |
|
|
|
logger.warning_once( |
|
f"The input hidden states seems to be silently casted in float32, this might be related to" |
|
f" the fact you have upcasted embedding or layer norm layers in float32. We will cast back the input in" |
|
f" {target_dtype}." |
|
) |
|
|
|
query_states = query_states.to(target_dtype) |
|
key_states = key_states.to(target_dtype) |
|
value_states = value_states.to(target_dtype) |
|
|
|
|
|
query_states = query_states.transpose(1, 2) |
|
key_states = key_states.transpose(1, 2) |
|
value_states = value_states.transpose(1, 2) |
|
|
|
attn_output = self._flash_attention_forward( |
|
query_states, |
|
key_states, |
|
value_states, |
|
attention_mask, |
|
q_len, |
|
dropout=dropout_rate, |
|
use_sliding_windows=use_sliding_windows, |
|
) |
|
|
|
attn_output = attn_output.reshape(bsz, q_len, self.hidden_size).contiguous() |
|
attn_output = self.o_proj(attn_output) |
|
|
|
if not output_attentions: |
|
attn_weights = None |
|
|
|
return attn_output, attn_weights, past_key_value |
|
|
|
def _flash_attention_forward( |
|
self, |
|
query_states, |
|
key_states, |
|
value_states, |
|
attention_mask, |
|
query_length, |
|
dropout=0.0, |
|
softmax_scale=None, |
|
use_sliding_windows=False, |
|
): |
|
""" |
|
Calls the forward method of Flash Attention - if the input hidden states contain at least one padding token |
|
first unpad the input, then computes the attention scores and pad the final attention scores. |
|
|
|
Args: |
|
query_states (`torch.Tensor`): |
|
Input query states to be passed to Flash Attention API |
|
key_states (`torch.Tensor`): |
|
Input key states to be passed to Flash Attention API |
|
value_states (`torch.Tensor`): |
|
Input value states to be passed to Flash Attention API |
|
attention_mask (`torch.Tensor`): |
|
The padding mask - corresponds to a tensor of size `(batch_size, seq_len)` where 0 stands for the |
|
position of padding tokens and 1 for the position of non-padding tokens. |
|
dropout (`int`, *optional*): |
|
Attention dropout |
|
softmax_scale (`float`, *optional*): |
|
The scaling of QK^T before applying softmax. Default to 1 / sqrt(head_dim) |
|
use_sliding_windows (`bool`, *optional*): |
|
Whether to activate sliding window attention. |
|
""" |
|
if not self._flash_attn_uses_top_left_mask: |
|
causal = self.is_causal |
|
else: |
|
|
|
causal = self.is_causal and query_length != 1 |
|
|
|
|
|
if attention_mask is not None: |
|
batch_size = query_states.shape[0] |
|
query_states, key_states, value_states, indices_q, cu_seq_lens, max_seq_lens = self._upad_input( |
|
query_states, key_states, value_states, attention_mask, query_length |
|
) |
|
|
|
cu_seqlens_q, cu_seqlens_k = cu_seq_lens |
|
max_seqlen_in_batch_q, max_seqlen_in_batch_k = max_seq_lens |
|
|
|
if not use_sliding_windows: |
|
attn_output_unpad = flash_attn_varlen_func( |
|
query_states, |
|
key_states, |
|
value_states, |
|
cu_seqlens_q=cu_seqlens_q, |
|
cu_seqlens_k=cu_seqlens_k, |
|
max_seqlen_q=max_seqlen_in_batch_q, |
|
max_seqlen_k=max_seqlen_in_batch_k, |
|
dropout_p=dropout, |
|
softmax_scale=softmax_scale, |
|
causal=causal, |
|
) |
|
else: |
|
attn_output_unpad = flash_attn_varlen_func( |
|
query_states, |
|
key_states, |
|
value_states, |
|
cu_seqlens_q=cu_seqlens_q, |
|
cu_seqlens_k=cu_seqlens_k, |
|
max_seqlen_q=max_seqlen_in_batch_q, |
|
max_seqlen_k=max_seqlen_in_batch_k, |
|
dropout_p=dropout, |
|
softmax_scale=softmax_scale, |
|
causal=causal, |
|
window_size=(self.config.sliding_window, self.config.sliding_window), |
|
) |
|
|
|
attn_output = pad_input(attn_output_unpad, indices_q, batch_size, query_length) |
|
else: |
|
if not use_sliding_windows: |
|
attn_output = flash_attn_func( |
|
query_states, |
|
key_states, |
|
value_states, |
|
dropout, |
|
softmax_scale=softmax_scale, |
|
causal=causal, |
|
) |
|
else: |
|
attn_output = flash_attn_func( |
|
query_states, |
|
key_states, |
|
value_states, |
|
dropout, |
|
softmax_scale=softmax_scale, |
|
causal=causal, |
|
window_size=(self.config.sliding_window, self.config.sliding_window), |
|
) |
|
|
|
return attn_output |
|
|
|
def _upad_input(self, query_layer, key_layer, value_layer, attention_mask, query_length): |
|
batch_size, kv_seq_len, num_heads, head_dim = key_layer.shape |
|
|
|
|
|
|
|
if kv_seq_len != attention_mask.shape[-1]: |
|
attention_mask_num_tokens = attention_mask.shape[-1] |
|
attention_mask = attention_mask[:, attention_mask_num_tokens - kv_seq_len :] |
|
|
|
indices_k, cu_seqlens_k, max_seqlen_in_batch_k = _get_unpad_data(attention_mask) |
|
|
|
key_layer = index_first_axis(key_layer.reshape(batch_size * kv_seq_len, num_heads, head_dim), indices_k) |
|
value_layer = index_first_axis(value_layer.reshape(batch_size * kv_seq_len, num_heads, head_dim), indices_k) |
|
|
|
if query_length == kv_seq_len: |
|
query_layer = index_first_axis( |
|
query_layer.reshape(batch_size * kv_seq_len, num_heads, head_dim), indices_k |
|
) |
|
cu_seqlens_q = cu_seqlens_k |
|
max_seqlen_in_batch_q = max_seqlen_in_batch_k |
|
indices_q = indices_k |
|
elif query_length == 1: |
|
max_seqlen_in_batch_q = 1 |
|
cu_seqlens_q = torch.arange( |
|
batch_size + 1, dtype=torch.int32, device=query_layer.device |
|
) |
|
indices_q = cu_seqlens_q[:-1] |
|
query_layer = query_layer.squeeze(1) |
|
else: |
|
|
|
attention_mask = attention_mask[:, -query_length:] |
|
query_layer, indices_q, cu_seqlens_q, max_seqlen_in_batch_q = unpad_input(query_layer, attention_mask) |
|
|
|
return ( |
|
query_layer, |
|
key_layer, |
|
value_layer, |
|
indices_q, |
|
(cu_seqlens_q, cu_seqlens_k), |
|
(max_seqlen_in_batch_q, max_seqlen_in_batch_k), |
|
) |
|
|
|
|
|
|
|
class JambaSdpaAttention(JambaAttention): |
|
""" |
|
Jamba attention module using torch.nn.functional.scaled_dot_product_attention. This module inherits from |
|
`JambaAttention` as the weights of the module stays untouched. The only changes are on the forward pass to adapt to |
|
SDPA API. |
|
""" |
|
|
|
|
|
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, |
|
) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]: |
|
if output_attentions: |
|
|
|
logger.warning_once( |
|
"JambaModel is using JambaSdpaAttention, but `torch.nn.functional.scaled_dot_product_attention` does not support `output_attentions=True`. Falling back to the manual attention implementation, " |
|
'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.' |
|
) |
|
return super().forward( |
|
hidden_states=hidden_states, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
past_key_value=past_key_value, |
|
output_attentions=output_attentions, |
|
use_cache=use_cache, |
|
) |
|
|
|
bsz, q_len, _ = hidden_states.size() |
|
|
|
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) |
|
|
|
kv_seq_len = key_states.shape[-2] |
|
if past_key_value is not None: |
|
kv_seq_len += past_key_value.get_usable_length(kv_seq_len, self.layer_idx) |
|
|
|
if past_key_value is not None: |
|
key_states, value_states = past_key_value.update(key_states, value_states, self.layer_idx) |
|
|
|
key_states = repeat_kv(key_states, self.num_key_value_groups) |
|
value_states = repeat_kv(value_states, self.num_key_value_groups) |
|
|
|
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()}" |
|
) |
|
|
|
|
|
|
|
if query_states.device.type == "cuda" and attention_mask is not None: |
|
query_states = query_states.contiguous() |
|
key_states = key_states.contiguous() |
|
value_states = value_states.contiguous() |
|
|
|
attn_output = torch.nn.functional.scaled_dot_product_attention( |
|
query_states, |
|
key_states, |
|
value_states, |
|
attn_mask=attention_mask, |
|
dropout_p=self.attention_dropout if self.training else 0.0, |
|
|
|
is_causal=self.is_causal and attention_mask is None and q_len > 1, |
|
) |
|
|
|
attn_output = attn_output.transpose(1, 2).contiguous() |
|
attn_output = attn_output.view(bsz, q_len, self.hidden_size) |
|
|
|
attn_output = self.o_proj(attn_output) |
|
|
|
return attn_output, None, past_key_value |
|
|
|
|
|
JAMBA_ATTENTION_CLASSES = { |
|
"eager": JambaAttention, |
|
"flash_attention_2": JambaFlashAttention2, |
|
"sdpa": JambaSdpaAttention, |
|
} |
|
|
|
|
|
class HybridMambaAttentionDynamicCache(DynamicCache): |
|
""" |
|
A dynamic cache that can handle both the attention cache (which has a seq_len dimension) and the mamba cache |
|
(which has a constant shape regardless of seq_len). |
|
|
|
It stores the Key and Value states as a list of tensors, one for each layer. |
|
The expected shape for each tensor for attention layers is `[batch_size, num_heads, seq_len, head_dim]`. |
|
For the mamba layers, the `key_cache` represents the convolution state and has a shape of `[batch_size, d_inner, 1, d_conv]`, |
|
and the `value_cache` represents the ssm state and has a shape of `[batch_size, d_inner, 1, d_state]`. Mamba cache |
|
shape[2] is a dummy "seqlen" dimension to match the number of attention cache dimensions. For mamba, the cache |
|
doesn't grow with seqlen so this dimension is always 1. |
|
""" |
|
|
|
def __init__(self) -> None: |
|
super().__init__() |
|
self.attention_layer_idx = None |
|
|
|
def update( |
|
self, |
|
key_states: torch.Tensor, |
|
value_states: torch.Tensor, |
|
layer_idx: int, |
|
cache_kwargs: Optional[Dict[str, Any]] = None, |
|
) -> Tuple[torch.Tensor, torch.Tensor]: |
|
""" |
|
Updates the cache with the new `key_states` and `value_states` for the layer `layer_idx`. |
|
|
|
Parameters: |
|
key_states (`torch.Tensor`): |
|
The new key states to cache. |
|
value_states (`torch.Tensor`): |
|
The new value states to cache. |
|
layer_idx (`int`): |
|
The index of the layer to cache the states for. |
|
cache_kwargs (`Dict[str, Any]`, `optional`): |
|
Additional arguments for the cache subclass. No additional arguments are used in `HybridMambaAttentionDynamicCache`. |
|
|
|
Return: |
|
A tuple containing the updated key and value states. |
|
""" |
|
|
|
if self.attention_layer_idx is None and self._is_attn_layer(key_states, value_states): |
|
self.attention_layer_idx = layer_idx |
|
if self.attention_layer_idx is not None and layer_idx == self.attention_layer_idx: |
|
if hasattr(self, "_seen_tokens"): |
|
self._seen_tokens += key_states.shape[-2] |
|
else: |
|
self.seen_tokens += key_states.shape[-2] |
|
|
|
|
|
if len(self.key_cache) <= layer_idx: |
|
self.key_cache.append(key_states) |
|
self.value_cache.append(value_states) |
|
else: |
|
if self._is_attn_layer(self.key_cache[layer_idx], self.value_cache[layer_idx]): |
|
|
|
self.key_cache[layer_idx] = torch.cat([self.key_cache[layer_idx], key_states], dim=-2) |
|
self.value_cache[layer_idx] = torch.cat([self.value_cache[layer_idx], value_states], dim=-2) |
|
else: |
|
|
|
self.key_cache[layer_idx] = key_states |
|
self.value_cache[layer_idx] = value_states |
|
|
|
return self.key_cache[layer_idx], self.value_cache[layer_idx] |
|
|
|
def get_seq_length(self, layer_idx: Optional[int] = None) -> int: |
|
"""Returns the sequence length of the cached states. A layer index can be optionally passed.""" |
|
if layer_idx is not None: |
|
if len(self.key_cache) <= layer_idx: |
|
return 0 |
|
if self._is_attn_layer(self.key_cache[layer_idx], self.value_cache[layer_idx]): |
|
return self.key_cache[layer_idx].shape[-2] |
|
else: |
|
warnings.warn( |
|
f"Asked to get the sequence length from cache of layer {layer_idx} which is not an attention layer. " |
|
f"Ignoring that and using an attention layer cache" |
|
) |
|
if self.attention_layer_idx is None or len(self.key_cache) <= self.attention_layer_idx: |
|
return 0 |
|
return self.key_cache[self.attention_layer_idx].shape[-2] |
|
|
|
@staticmethod |
|
def _is_attn_layer(key_states: torch.Tensor, value_states: torch.Tensor): |
|
return key_states.shape[-1] == value_states.shape[-1] |
|
|
|
|
|
@dataclass |
|
class MambaCacheParams: |
|
seqlen_offset: int = 0 |
|
conv_states: Dict[int, torch.Tensor] = field(default_factory=dict) |
|
ssm_states: Dict[int, torch.Tensor] = field(default_factory=dict) |
|
|
|
|
|
|
|
class JambaMambaMixer(nn.Module): |
|
""" |
|
Compute ∆, A, B, C, and D the state space parameters and compute the `contextualized_states`. |
|
A, D are input independent (see Mamba paper [1] Section 3.5.2 "Interpretation of A" for why A isn't selective) |
|
∆, B, C are input-dependent (this is a key difference between Mamba and the linear time invariant S4, |
|
and is why Mamba is called **selective** state spaces) |
|
""" |
|
|
|
def __init__(self, config: JambaConfig, layer_idx): |
|
super().__init__() |
|
self.config = config |
|
self.layer_idx = layer_idx |
|
self.hidden_size = config.hidden_size |
|
self.ssm_state_size = config.mamba_d_state |
|
self.conv_kernel_size = config.mamba_d_conv |
|
self.intermediate_size = config.mamba_expand * config.hidden_size |
|
self.time_step_rank = config.mamba_dt_rank |
|
self.use_conv_bias = config.mamba_conv_bias |
|
self.use_bias = config.mamba_proj_bias |
|
self.conv1d = nn.Conv1d( |
|
in_channels=self.intermediate_size, |
|
out_channels=self.intermediate_size, |
|
bias=self.use_conv_bias, |
|
kernel_size=self.conv_kernel_size, |
|
groups=self.intermediate_size, |
|
padding=self.conv_kernel_size - 1, |
|
) |
|
|
|
self.activation = config.hidden_act |
|
self.act = ACT2FN[config.hidden_act] |
|
self.apply_inner_layernorms = config.mamba_inner_layernorms |
|
|
|
self.use_fast_kernels = config.use_mamba_kernels |
|
|
|
|
|
self.in_proj = nn.Linear(self.hidden_size, self.intermediate_size * 2, bias=self.use_bias) |
|
|
|
self.x_proj = nn.Linear(self.intermediate_size, self.time_step_rank + self.ssm_state_size * 2, bias=False) |
|
|
|
self.dt_proj = nn.Linear(self.time_step_rank, self.intermediate_size, bias=True) |
|
|
|
|
|
|
|
A = torch.arange(1, self.ssm_state_size + 1, dtype=torch.float32)[None, :] |
|
A = A.expand(self.intermediate_size, -1).contiguous() |
|
|
|
self.A_log = nn.Parameter(torch.log(A)) |
|
self.D = nn.Parameter(torch.ones(self.intermediate_size)) |
|
self.out_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=self.use_bias) |
|
|
|
if self.apply_inner_layernorms: |
|
self.dt_layernorm = JambaRMSNorm(self.time_step_rank, eps=config.rms_norm_eps) |
|
self.B_layernorm = JambaRMSNorm(self.ssm_state_size, eps=config.rms_norm_eps) |
|
self.C_layernorm = JambaRMSNorm(self.ssm_state_size, eps=config.rms_norm_eps) |
|
else: |
|
self.dt_layernorm = None |
|
self.B_layernorm = None |
|
self.C_layernorm = None |
|
|
|
if not is_fast_path_available: |
|
logger.warning_once( |
|
"The fast path is not available because on of `(selective_state_update, selective_scan_fn, causal_conv1d_fn, causal_conv1d_update, mamba_inner_fn)`" |
|
" is None. To install follow https://github.com/state-spaces/mamba/#installation and" |
|
" https://github.com/Dao-AILab/causal-conv1d. If you want to use the naive implementation, set `use_mamba_kernels=False` in the model config" |
|
) |
|
|
|
def _apply_layernorms(self, dt, B, C): |
|
if self.dt_layernorm is not None: |
|
dt = self.dt_layernorm(dt) |
|
if self.B_layernorm is not None: |
|
B = self.B_layernorm(B) |
|
if self.C_layernorm is not None: |
|
C = self.C_layernorm(C) |
|
return dt, B, C |
|
|
|
def cuda_kernels_forward(self, hidden_states: torch.Tensor, cache_params: MambaCacheParams = None): |
|
|
|
projected_states = self.in_proj(hidden_states).transpose(1, 2) |
|
|
|
if ( |
|
self.training and cache_params is None and not self.apply_inner_layernorms |
|
): |
|
contextualized_states = mamba_inner_fn( |
|
projected_states, |
|
self.conv1d.weight, |
|
self.conv1d.bias if self.use_conv_bias else None, |
|
self.x_proj.weight, |
|
self.dt_proj.weight, |
|
self.out_proj.weight, |
|
self.out_proj.bias.float() if self.use_bias else None, |
|
-torch.exp(self.A_log.float()), |
|
None, |
|
None, |
|
self.D.float(), |
|
delta_bias=self.dt_proj.bias.float(), |
|
delta_softplus=True, |
|
) |
|
|
|
else: |
|
hidden_states, gate = projected_states.chunk(2, dim=1) |
|
|
|
|
|
conv_weights = self.conv1d.weight.view(self.conv1d.weight.size(0), self.conv1d.weight.size(2)) |
|
if cache_params is not None and cache_params.seqlen_offset > 0: |
|
hidden_states = causal_conv1d_update( |
|
hidden_states.squeeze(-1), |
|
cache_params.conv_states[self.layer_idx], |
|
conv_weights, |
|
self.conv1d.bias, |
|
self.activation, |
|
) |
|
hidden_states = hidden_states.unsqueeze(-1) |
|
else: |
|
if cache_params is not None: |
|
conv_states = nn.functional.pad( |
|
hidden_states, (self.conv_kernel_size - hidden_states.shape[-1], 0) |
|
) |
|
cache_params.conv_states[self.layer_idx].copy_(conv_states) |
|
hidden_states = causal_conv1d_fn( |
|
hidden_states, conv_weights, self.conv1d.bias, activation=self.activation |
|
) |
|
|
|
|
|
|
|
ssm_parameters = self.x_proj(hidden_states.transpose(1, 2)) |
|
time_step, B, C = torch.split( |
|
ssm_parameters, [self.time_step_rank, self.ssm_state_size, self.ssm_state_size], dim=-1 |
|
) |
|
time_step, B, C = self._apply_layernorms(time_step, B, C) |
|
|
|
|
|
|
|
|
|
|
|
|
|
dt_proj_bias = self.dt_proj.bias |
|
self.dt_proj.bias = None |
|
discrete_time_step = self.dt_proj(time_step).transpose(1, 2) |
|
self.dt_proj.bias = dt_proj_bias |
|
|
|
A = -torch.exp(self.A_log.float()) |
|
|
|
time_proj_bias = self.dt_proj.bias.float() if hasattr(self.dt_proj, "bias") else None |
|
if cache_params is not None and cache_params.seqlen_offset > 0: |
|
scan_outputs = selective_state_update( |
|
cache_params.ssm_states[self.layer_idx], |
|
hidden_states[..., 0], |
|
discrete_time_step[..., 0], |
|
A, |
|
B[:, 0], |
|
C[:, 0], |
|
self.D, |
|
gate[..., 0], |
|
time_proj_bias, |
|
dt_softplus=True, |
|
).unsqueeze(-1) |
|
else: |
|
scan_outputs, ssm_state = selective_scan_fn( |
|
hidden_states, |
|
discrete_time_step, |
|
A, |
|
B.transpose(1, 2), |
|
C.transpose(1, 2), |
|
self.D.float(), |
|
gate, |
|
time_proj_bias, |
|
delta_softplus=True, |
|
return_last_state=True, |
|
) |
|
if ssm_state is not None and cache_params is not None: |
|
cache_params.ssm_states[self.layer_idx].copy_(ssm_state) |
|
|
|
|
|
contextualized_states = self.out_proj(scan_outputs.transpose(1, 2)) |
|
return contextualized_states |
|
|
|
|
|
def slow_forward(self, input_states, cache_params: MambaCacheParams = None): |
|
batch_size, seq_len, _ = input_states.shape |
|
dtype = input_states.dtype |
|
|
|
projected_states = self.in_proj(input_states).transpose(1, 2) |
|
hidden_states, gate = projected_states.chunk(2, dim=1) |
|
|
|
|
|
if cache_params is not None: |
|
if self.training: |
|
|
|
ssm_state = cache_params.ssm_states[self.layer_idx].clone() |
|
else: |
|
ssm_state = cache_params.ssm_states[self.layer_idx] |
|
|
|
if cache_params.seqlen_offset > 0: |
|
conv_state = cache_params.conv_states[self.layer_idx] |
|
conv_state = torch.roll(conv_state, shifts=-1, dims=-1) |
|
conv_state[:, :, -1] = hidden_states[:, :, 0] |
|
cache_params.conv_states[self.layer_idx].copy_(conv_state) |
|
hidden_states = torch.sum(conv_state * self.conv1d.weight[:, 0, :], dim=-1) |
|
if self.use_conv_bias: |
|
hidden_states += self.conv1d.bias |
|
hidden_states = self.act(hidden_states).to(dtype).unsqueeze(-1) |
|
else: |
|
conv_state = nn.functional.pad( |
|
hidden_states, |
|
(self.conv_kernel_size - hidden_states.shape[-1], 0) |
|
) |
|
cache_params.conv_states[self.layer_idx].copy_(conv_state) |
|
hidden_states = self.act(self.conv1d(hidden_states)[..., :seq_len]) |
|
else: |
|
ssm_state = torch.zeros( |
|
(batch_size, self.intermediate_size, self.ssm_state_size), |
|
device=hidden_states.device, dtype=dtype |
|
) |
|
hidden_states = self.act(self.conv1d(hidden_states)[..., :seq_len]) |
|
|
|
|
|
|
|
ssm_parameters = self.x_proj(hidden_states.transpose(1, 2)) |
|
time_step, B, C = torch.split( |
|
ssm_parameters, [self.time_step_rank, self.ssm_state_size, self.ssm_state_size], dim=-1 |
|
) |
|
time_step, B, C = self._apply_layernorms(time_step, B, C) |
|
discrete_time_step = self.dt_proj(time_step) |
|
discrete_time_step = nn.functional.softplus(discrete_time_step).transpose(1, 2) |
|
|
|
|
|
A = -torch.exp(self.A_log.float()) |
|
discrete_A = torch.exp(A[None, :, None, :] * discrete_time_step[:, :, :, None]) |
|
discrete_B = discrete_time_step[:, :, :, None] * B[:, None, :, :].float() |
|
deltaB_u = discrete_B * hidden_states[:, :, :, None].float() |
|
|
|
|
|
scan_outputs = [] |
|
for i in range(seq_len): |
|
ssm_state = discrete_A[:, :, i, :] * ssm_state + deltaB_u[:, :, i, :] |
|
scan_output = torch.matmul(ssm_state.to(dtype), C[:, i, :].unsqueeze(-1)) |
|
scan_outputs.append(scan_output[:, :, 0]) |
|
scan_output = torch.stack(scan_outputs, dim=-1) |
|
scan_output = scan_output + (hidden_states * self.D[None, :, None]) |
|
scan_output = (scan_output * self.act(gate)) |
|
|
|
if cache_params is not None: |
|
cache_params.ssm_states[self.layer_idx].copy_(ssm_state) |
|
|
|
|
|
contextualized_states = self.out_proj(scan_output.transpose(1, 2)) |
|
return contextualized_states |
|
|
|
|
|
def mixer_forward(self, hidden_states, cache_params: MambaCacheParams = None): |
|
if self.use_fast_kernels: |
|
if not is_fast_path_available or "cuda" not in self.x_proj.weight.device.type: |
|
raise ValueError( |
|
"Fast Mamba kernels are not available. Make sure to they are installed and that the mamba module is on a CUDA device" |
|
) |
|
return self.cuda_kernels_forward(hidden_states, cache_params) |
|
return self.slow_forward(hidden_states, cache_params) |
|
|
|
def forward( |
|
self, |
|
hidden_states: torch.Tensor, |
|
past_key_value: Optional[HybridMambaAttentionDynamicCache] = None, |
|
**kwargs, |
|
) -> Tuple[torch.Tensor, Optional[Tuple[torch.Tensor]]]: |
|
if past_key_value is not None: |
|
cache_params = MambaCacheParams( |
|
seqlen_offset=0 if hidden_states.shape[1] > 1 else past_key_value.seen_tokens, |
|
) |
|
if len(past_key_value.key_cache) > self.layer_idx: |
|
|
|
|
|
cache_params.conv_states[self.layer_idx] = past_key_value.key_cache[self.layer_idx].squeeze(2) |
|
cache_params.ssm_states[self.layer_idx] = past_key_value.value_cache[self.layer_idx].squeeze(2) |
|
else: |
|
|
|
batch_size = hidden_states.shape[0] |
|
cache_params.conv_states[self.layer_idx] = torch.zeros( |
|
batch_size, |
|
self.intermediate_size, |
|
self.conv_kernel_size, |
|
device=hidden_states.device, |
|
dtype=hidden_states.dtype, |
|
) |
|
cache_params.ssm_states[self.layer_idx] = torch.zeros( |
|
batch_size, |
|
self.intermediate_size, |
|
self.ssm_state_size, |
|
device=hidden_states.device, |
|
dtype=hidden_states.dtype, |
|
) |
|
else: |
|
cache_params = None |
|
|
|
res = self.mixer_forward(hidden_states, cache_params) |
|
|
|
if past_key_value is not None: |
|
past_key_value.update( |
|
|
|
cache_params.conv_states[self.layer_idx].unsqueeze(2), |
|
cache_params.ssm_states[self.layer_idx].unsqueeze(2), |
|
self.layer_idx, |
|
) |
|
|
|
return res, past_key_value |
|
|
|
|
|
class JambaMLP(nn.Module): |
|
def __init__(self, config: JambaConfig): |
|
super().__init__() |
|
self.ffn_dim = config.intermediate_size |
|
self.hidden_dim = config.hidden_size |
|
|
|
self.gate_proj = nn.Linear(self.hidden_dim, self.ffn_dim, bias=False) |
|
self.down_proj = nn.Linear(self.ffn_dim, self.hidden_dim, bias=False) |
|
self.up_proj = nn.Linear(self.hidden_dim, self.ffn_dim, bias=False) |
|
|
|
self.act_fn = ACT2FN[config.hidden_act] |
|
|
|
def forward(self, x): |
|
return self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x)) |
|
|
|
|
|
|
|
class JambaSparseMoeBlock(nn.Module): |
|
""" |
|
This implementation is |
|
strictly equivalent to standard MoE with full capacity (no |
|
dropped tokens). It's faster since it formulates MoE operations |
|
in terms of block-sparse operations to accomodate imbalanced |
|
assignments of tokens to experts, whereas standard MoE either |
|
(1) drop tokens at the cost of reduced performance or (2) set |
|
capacity factor to number of experts and thus waste computation |
|
and memory on padding. |
|
""" |
|
|
|
def __init__(self, config: JambaConfig, num_experts: int, num_experts_per_tok: int): |
|
super().__init__() |
|
self.hidden_dim = config.hidden_size |
|
self.ffn_dim = config.intermediate_size |
|
|
|
|
|
self.num_experts = num_experts |
|
self.top_k = num_experts_per_tok |
|
|
|
if num_experts > 1: |
|
|
|
self.router = nn.Linear(self.hidden_dim, self.num_experts, bias=False) |
|
else: |
|
self.router = None |
|
|
|
self.experts = nn.ModuleList([JambaMLP(config) for _ in range(self.num_experts)]) |
|
|
|
def forward(self, hidden_states: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor]: |
|
""" """ |
|
batch_size, sequence_length, hidden_dim = hidden_states.shape |
|
|
|
if self.num_experts == 1: |
|
|
|
final_hidden_states = self.experts[0](hidden_states) |
|
router_logits = torch.ones( |
|
(batch_size * sequence_length, 1), |
|
device=hidden_states.device, |
|
dtype=hidden_states.dtype, |
|
requires_grad=hidden_states.requires_grad, |
|
) |
|
return final_hidden_states, router_logits |
|
|
|
|
|
hidden_states = hidden_states.view(-1, hidden_dim) |
|
|
|
router_logits = self.router(hidden_states) |
|
routing_weights = F.softmax(router_logits, dim=1, dtype=torch.float) |
|
routing_weights, selected_experts = torch.topk(routing_weights, self.top_k, dim=-1) |
|
|
|
routing_weights = routing_weights.to(hidden_states.dtype) |
|
|
|
final_hidden_states = torch.zeros( |
|
(batch_size * sequence_length, hidden_dim), dtype=hidden_states.dtype, device=hidden_states.device |
|
) |
|
|
|
|
|
|
|
expert_mask = torch.nn.functional.one_hot(selected_experts, num_classes=self.num_experts).permute(2, 1, 0) |
|
|
|
|
|
for expert_idx in range(self.num_experts): |
|
expert_layer = self.experts[expert_idx] |
|
idx, top_x = torch.where(expert_mask[expert_idx]) |
|
|
|
if top_x.shape[0] == 0: |
|
continue |
|
|
|
|
|
top_x_list = top_x.tolist() |
|
idx_list = idx.tolist() |
|
|
|
|
|
|
|
|
|
current_state = hidden_states[None, top_x_list].reshape(-1, hidden_dim) |
|
current_hidden_states = expert_layer(current_state) * routing_weights[top_x_list, idx_list, None] |
|
|
|
|
|
|
|
final_hidden_states.index_add_(0, top_x, current_hidden_states.to(hidden_states.dtype)) |
|
final_hidden_states = final_hidden_states.reshape(batch_size, sequence_length, hidden_dim) |
|
return final_hidden_states, router_logits |
|
|
|
|
|
class JambaAttentionDecoderLayer(nn.Module): |
|
def __init__(self, config: JambaConfig, num_experts: int, layer_idx: int): |
|
super().__init__() |
|
|
|
self.self_attn = JAMBA_ATTENTION_CLASSES[config._attn_implementation](config, layer_idx) |
|
|
|
num_experts_per_tok = config.num_experts_per_tok if num_experts > 1 else 1 |
|
self.moe = JambaSparseMoeBlock(config, num_experts=num_experts, num_experts_per_tok=num_experts_per_tok) |
|
self.input_layernorm = JambaRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
|
self.pre_moe_layernorm = JambaRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
|
|
|
def forward( |
|
self, |
|
hidden_states: torch.Tensor, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_value: Optional[Tuple[torch.Tensor]] = None, |
|
output_attentions: Optional[bool] = False, |
|
output_router_logits: Optional[bool] = False, |
|
use_cache: Optional[bool] = False, |
|
**kwargs, |
|
) -> Tuple[torch.FloatTensor, Optional[Tuple[torch.FloatTensor, torch.FloatTensor]]]: |
|
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.`" |
|
) |
|
""" |
|
Args: |
|
hidden_states (`torch.FloatTensor`): input to the layer of shape `(batch, seq_len, embed_dim)` |
|
attention_mask (`torch.FloatTensor`, *optional*): attention mask of size |
|
`(batch, sequence_length)` where padding elements are indicated by 0. |
|
past_key_value (`Tuple(torch.FloatTensor)`, *optional*): cached past key and value projection states |
|
output_attentions (`bool`, *optional*): |
|
Whether or not to return the attentions tensors of all attention layers. See `attentions` under |
|
returned tensors for more detail. |
|
output_router_logits (`bool`, *optional*): |
|
Whether or not to return the logits of all the routers. They are useful for computing the router loss, and |
|
should not be returned during inference. |
|
use_cache (`bool`, *optional*): |
|
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding |
|
(see `past_key_values`). |
|
""" |
|
|
|
residual = hidden_states |
|
|
|
hidden_states = self.input_layernorm(hidden_states) |
|
|
|
hidden_states, self_attn_weights, present_key_value = self.self_attn( |
|
hidden_states=hidden_states, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
past_key_value=past_key_value, |
|
output_attentions=output_attentions, |
|
use_cache=use_cache, |
|
) |
|
|
|
|
|
hidden_states = residual + hidden_states |
|
|
|
|
|
residual = hidden_states |
|
hidden_states = self.pre_moe_layernorm(hidden_states) |
|
hidden_states, router_logits = self.moe(hidden_states) |
|
hidden_states = residual + hidden_states |
|
|
|
outputs = (hidden_states,) |
|
|
|
if output_attentions: |
|
outputs += (self_attn_weights,) |
|
|
|
if use_cache: |
|
outputs += (present_key_value,) |
|
|
|
if output_router_logits: |
|
outputs += (router_logits,) |
|
|
|
return outputs |
|
|
|
|
|
class JambaMambaDecoderLayer(nn.Module): |
|
def __init__(self, config: JambaConfig, num_experts: int, layer_idx: int): |
|
super().__init__() |
|
|
|
self.mamba = JambaMambaMixer(config=config, layer_idx=layer_idx) |
|
|
|
num_experts_per_tok = config.num_experts_per_tok if num_experts > 1 else 1 |
|
self.moe = JambaSparseMoeBlock(config, num_experts=num_experts, num_experts_per_tok=num_experts_per_tok) |
|
self.input_layernorm = JambaRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
|
self.pre_moe_layernorm = JambaRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
|
|
|
def forward( |
|
self, |
|
hidden_states: torch.Tensor, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_value: Optional[HybridMambaAttentionDynamicCache] = None, |
|
output_attentions: Optional[bool] = False, |
|
output_router_logits: Optional[bool] = False, |
|
use_cache: Optional[bool] = False, |
|
**kwargs, |
|
) -> Tuple[torch.FloatTensor, Optional[Tuple[torch.FloatTensor, torch.FloatTensor]]]: |
|
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.`" |
|
) |
|
""" |
|
Args: |
|
hidden_states (`torch.FloatTensor`): input to the layer of shape `(batch, seq_len, embed_dim)` |
|
attention_mask (`torch.FloatTensor`, *optional*): attention mask of size |
|
`(batch, sequence_length)` where padding elements are indicated by 0. |
|
past_key_value (`Tuple(torch.FloatTensor)`, *optional*): cached past key and value projection states |
|
output_attentions (`bool`, *optional*): |
|
Whether or not to return the attentions tensors of all attention layers. See `attentions` under |
|
returned tensors for more detail. |
|
output_router_logits (`bool`, *optional*): |
|
Whether or not to return the logits of all the routers. They are useful for computing the router loss, and |
|
should not be returned during inference. |
|
use_cache (`bool`, *optional*): |
|
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding |
|
(see `past_key_values`). |
|
""" |
|
|
|
residual = hidden_states |
|
|
|
hidden_states = self.input_layernorm(hidden_states) |
|
|
|
hidden_states, present_key_value = self.mamba( |
|
hidden_states=hidden_states, |
|
past_key_value=past_key_value, |
|
) |
|
bs, seqlen, _ = hidden_states.shape |
|
past_seqlen = self._get_past_seqlen(past_key_value, seqlen) |
|
num_attention_heads = self.mamba.config.num_attention_heads |
|
self_attn_weights = torch.empty(bs, num_attention_heads, seqlen, past_seqlen, device="meta") |
|
|
|
|
|
hidden_states = residual + hidden_states |
|
|
|
|
|
residual = hidden_states |
|
hidden_states = self.pre_moe_layernorm(hidden_states) |
|
hidden_states, router_logits = self.moe(hidden_states) |
|
hidden_states = residual + hidden_states |
|
|
|
outputs = (hidden_states,) |
|
|
|
if output_attentions: |
|
outputs += (self_attn_weights,) |
|
|
|
if use_cache: |
|
outputs += (present_key_value,) |
|
|
|
if output_router_logits: |
|
outputs += (router_logits,) |
|
|
|
return outputs |
|
|
|
def _get_past_seqlen(self, past_key_value, seqlen): |
|
if past_key_value is None: |
|
return seqlen |
|
past_seqlen = past_key_value.get_seq_length() |
|
if past_seqlen == 0: |
|
return seqlen |
|
if past_key_value.attention_layer_idx is None: |
|
return seqlen |
|
if self.mamba.layer_idx < past_key_value.attention_layer_idx: |
|
return past_seqlen + 1 |
|
return past_seqlen |
|
|
|
|
|
JAMBA_START_DOCSTRING = r""" |
|
This model inherits from [`PreTrainedModel`]. Check the superclass documentation for the generic methods the |
|
library implements for all its model (such as downloading or saving, resizing the input embeddings, pruning heads |
|
etc.) |
|
|
|
This model is also a PyTorch [torch.nn.Module](https://pytorch.org/docs/stable/nn.html#torch.nn.Module) subclass. |
|
Use it as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage |
|
and behavior. |
|
|
|
Parameters: |
|
config ([`JambaConfig`]): |
|
Model configuration class with all the parameters of the model. Initializing with a config file does not |
|
load the weights associated with the model, only the configuration. Check out the |
|
[`~PreTrainedModel.from_pretrained`] method to load the model weights. |
|
""" |
|
|
|
|
|
@add_start_docstrings( |
|
"The bare Jamba Model outputting raw hidden-states without any specific head on top.", |
|
JAMBA_START_DOCSTRING, |
|
) |
|
|
|
class JambaPreTrainedModel(PreTrainedModel): |
|
config_class = JambaConfig |
|
base_model_prefix = "model" |
|
supports_gradient_checkpointing = True |
|
_no_split_modules = ["JambaAttentionDecoderLayer", "JambaMambaDecoderLayer"] |
|
_skip_keys_device_placement = "past_key_values" |
|
_supports_flash_attn_2 = True |
|
_supports_sdpa = True |
|
_supports_cache_class = True |
|
|
|
def _init_weights(self, module): |
|
std = self.config.initializer_range |
|
if isinstance(module, (nn.Linear, nn.Conv1d)): |
|
module.weight.data.normal_(mean=0.0, std=std) |
|
if module.bias is not None: |
|
module.bias.data.zero_() |
|
elif isinstance(module, nn.Embedding): |
|
module.weight.data.normal_(mean=0.0, std=std) |
|
if module.padding_idx is not None: |
|
module.weight.data[module.padding_idx].zero_() |
|
|
|
@staticmethod |
|
def _convert_to_standard_cache( |
|
past_key_value: Tuple[Tuple[torch.Tensor, torch.Tensor]], batch_size: int |
|
) -> Tuple[Tuple[torch.Tensor, torch.Tensor]]: |
|
""" |
|
Standardizes the format of the cache so as to match most implementations, i.e. have the seqlen as the third dim |
|
also for mamba layers |
|
""" |
|
attn_layer_index = [k.shape == v.shape for k, v in past_key_value].index(True) |
|
seqlen = past_key_value[attn_layer_index][0].shape[2] |
|
standard_past_key_value = () |
|
for k, v in past_key_value: |
|
if k.shape != v.shape: |
|
|
|
|
|
standard_past_key_value += ((k.expand(-1, -1, seqlen, -1), v.expand(-1, -1, seqlen, -1)),) |
|
else: |
|
standard_past_key_value += ((k, v),) |
|
return standard_past_key_value |
|
|
|
@staticmethod |
|
def _convert_to_jamba_cache( |
|
past_key_value: Tuple[Tuple[torch.Tensor, torch.Tensor]], |
|
) -> Tuple[Tuple[torch.Tensor, torch.Tensor]]: |
|
""" |
|
Converts the cache to the format expected by Jamba, i.e. dummy seqlen dimesion with size 1 for mamba layers |
|
""" |
|
jamba_past_key_value = () |
|
for k, v in past_key_value: |
|
if k.shape != v.shape: |
|
|
|
jamba_past_key_value += ((k[:, :, :1, :], v[:, :, :1, :]),) |
|
else: |
|
jamba_past_key_value += ((k, v),) |
|
return jamba_past_key_value |
|
|
|
|
|
JAMBA_INPUTS_DOCSTRING = r""" |
|
Args: |
|
input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`): |
|
Indices of input sequence tokens in the vocabulary. Padding will be ignored by default should you provide |
|
it. |
|
|
|
Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and |
|
[`PreTrainedTokenizer.__call__`] for details. |
|
|
|
[What are input IDs?](../glossary#input-ids) |
|
attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*): |
|
Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`: |
|
|
|
- 1 for tokens that are **not masked**, |
|
- 0 for tokens that are **masked**. |
|
|
|
[What are attention masks?](../glossary#attention-mask) |
|
|
|
Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and |
|
[`PreTrainedTokenizer.__call__`] for details. |
|
|
|
If `past_key_values` is used, optionally only the last `input_ids` have to be input (see |
|
`past_key_values`). |
|
|
|
If you want to change padding behavior, you should read [`modeling_opt._prepare_decoder_attention_mask`] |
|
and modify to your needs. See diagram 1 in [the paper](https://arxiv.org/abs/1910.13461) for more |
|
information on the default strategy. |
|
|
|
- 1 indicates the head is **not masked**, |
|
- 0 indicates the head is **masked**. |
|
position_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*): |
|
Indices of positions of each input sequence tokens in the position embeddings. Selected in the range `[0, |
|
config.n_positions - 1]`. |
|
|
|
[What are position IDs?](../glossary#position-ids) |
|
past_key_values (`tuple(tuple(torch.FloatTensor))`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`): |
|
Tuple of `tuple(torch.FloatTensor)` of length `config.num_hidden_layers`, with each tuple having 2 tensors |
|
corresponding to the cache of the layer. |
|
For attention layers, both tensors have shape of `(batch_size, num_kv_heads, sequence_length, embed_size_per_head)` |
|
For mamba layers, the first tensor represents the convolution state and has shape of `(batch_size, d_inner, 1, d_conv)`, |
|
and the second tensor represents the ssm state and has shape of `(batch_size, d_inner, 1, d_state)`. Mamba |
|
cache shape[2] is a dummy "seqlen" dimension to match the number of attention cache dimensions. For mamba, |
|
the cache doesn't grow with seqlen so this dimension is always 1. |
|
|
|
Contains pre-computed hidden-states (key and values in the self-attention blocks and convolution and |
|
ssm states in the mamba blocks) that can be used (see `past_key_values` input) to speed up sequential decoding. |
|
|
|
If `past_key_values` are used, the user can optionally input only the last `input_ids` (those that |
|
don't have their past key value states given to this model) of shape `(batch_size, 1)` instead of all |
|
`input_ids` of shape `(batch_size, sequence_length)`. |
|
inputs_embeds (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`, *optional*): |
|
Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation. This |
|
is useful if you want more control over how to convert `input_ids` indices into associated vectors than the |
|
model's internal embedding lookup matrix. |
|
use_cache (`bool`, *optional*): |
|
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding (see |
|
`past_key_values`). |
|
output_attentions (`bool`, *optional*): |
|
Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned |
|
tensors for more detail. |
|
output_hidden_states (`bool`, *optional*): |
|
Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for |
|
more detail. |
|
output_router_logits (`bool`, *optional*): |
|
Whether or not to return the logits of all the routers. They are useful for computing the router loss, and |
|
should not be returned during inference. |
|
return_dict (`bool`, *optional*): |
|
Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple. |
|
""" |
|
|
|
|
|
@add_start_docstrings( |
|
"The bare Jamba Model outputting raw hidden-states without any specific head on top.", |
|
JAMBA_START_DOCSTRING, |
|
) |
|
|
|
class JambaModel(JambaPreTrainedModel): |
|
""" |
|
Transformer decoder consisting of *config.num_hidden_layers* layers. Each layer is a [`JambaDecoderLayer`] |
|
|
|
Args: |
|
config: JambaConfig |
|
""" |
|
|
|
def __init__(self, config: JambaConfig): |
|
super().__init__(config) |
|
self.padding_idx = config.pad_token_id |
|
self.vocab_size = config.vocab_size |
|
|
|
self.embed_tokens = nn.Embedding(config.vocab_size, config.hidden_size, self.padding_idx) |
|
|
|
|
|
decoder_layers = [] |
|
for i in range(config.num_hidden_layers): |
|
is_attn = True if (i - self.config.attn_layer_offset) % self.config.attn_layer_period == 0 else False |
|
is_expert = True if (i - self.config.expert_layer_offset) % self.config.expert_layer_period == 0 else False |
|
|
|
num_experts = self.config.num_experts if is_expert else 1 |
|
if is_attn: |
|
decoder_layers.append(JambaAttentionDecoderLayer(config, num_experts=num_experts, layer_idx=i)) |
|
else: |
|
decoder_layers.append(JambaMambaDecoderLayer(config, num_experts=num_experts, layer_idx=i)) |
|
|
|
if not any(isinstance(layer, JambaAttentionDecoderLayer) for layer in decoder_layers): |
|
raise ValueError("At least one layer in the decoder must be an attention layer") |
|
self._attn_layer_index = [isinstance(layer, JambaAttentionDecoderLayer) for layer in decoder_layers].index( |
|
True |
|
) |
|
|
|
if not any(isinstance(layer, JambaMambaDecoderLayer) for layer in decoder_layers): |
|
raise ValueError("At least one layer in the decoder must be a Mamba layer") |
|
self._mamba_layer_index = [isinstance(layer, JambaMambaDecoderLayer) for layer in decoder_layers].index(True) |
|
|
|
if ( |
|
decoder_layers[self._mamba_layer_index].mamba.ssm_state_size |
|
== decoder_layers[self._mamba_layer_index].mamba.conv_kernel_size |
|
): |
|
raise ValueError("Mamba state size and convolution size must be different") |
|
|
|
self.layers = nn.ModuleList(decoder_layers) |
|
|
|
self._attn_implementation = config._attn_implementation |
|
self.final_layernorm = JambaRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
|
|
|
self.gradient_checkpointing = False |
|
|
|
self.post_init() |
|
|
|
def get_input_embeddings(self): |
|
return self.embed_tokens |
|
|
|
def set_input_embeddings(self, value): |
|
self.embed_tokens = value |
|
|
|
|
|
@add_start_docstrings_to_model_forward(JAMBA_INPUTS_DOCSTRING) |
|
def forward( |
|
self, |
|
input_ids: torch.LongTensor = None, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_values: Optional[Union[List[torch.FloatTensor], HybridMambaAttentionDynamicCache]] = None, |
|
inputs_embeds: Optional[torch.FloatTensor] = None, |
|
use_cache: Optional[bool] = None, |
|
output_attentions: Optional[bool] = None, |
|
output_hidden_states: Optional[bool] = None, |
|
output_router_logits: Optional[bool] = None, |
|
return_dict: Optional[bool] = None, |
|
) -> Union[Tuple, MoeModelOutputWithPast]: |
|
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions |
|
output_router_logits = ( |
|
output_router_logits if output_router_logits is not None else self.config.output_router_logits |
|
) |
|
output_hidden_states = ( |
|
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states |
|
) |
|
use_cache = use_cache if use_cache is not None else self.config.use_cache |
|
|
|
return_dict = return_dict if return_dict is not None else self.config.use_return_dict |
|
|
|
|
|
if input_ids is not None and inputs_embeds is not None: |
|
raise ValueError("You cannot specify both input_ids and inputs_embeds at the same time") |
|
elif input_ids is not None: |
|
batch_size, seq_length = input_ids.shape |
|
elif inputs_embeds is not None: |
|
batch_size, seq_length, _ = inputs_embeds.shape |
|
else: |
|
raise ValueError("You have to specify either input_ids or inputs_embeds") |
|
|
|
past_key_values_length = 0 |
|
|
|
if self.gradient_checkpointing and self.training: |
|
if use_cache: |
|
logger.warning_once( |
|
"`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`..." |
|
) |
|
use_cache = False |
|
|
|
if use_cache: |
|
if isinstance(past_key_values, Cache) and not isinstance( |
|
past_key_values, HybridMambaAttentionDynamicCache |
|
): |
|
past_key_values = HybridMambaAttentionDynamicCache.from_legacy_cache(past_key_values.to_legacy_cache()) |
|
use_legacy_cache = not isinstance(past_key_values, HybridMambaAttentionDynamicCache) |
|
if use_legacy_cache: |
|
past_key_values = HybridMambaAttentionDynamicCache.from_legacy_cache(past_key_values) |
|
past_key_values_length = past_key_values.get_usable_length(seq_length, self._attn_layer_index) |
|
|
|
if position_ids is None: |
|
device = input_ids.device if input_ids is not None else inputs_embeds.device |
|
position_ids = torch.arange( |
|
past_key_values_length, seq_length + past_key_values_length, dtype=torch.long, device=device |
|
) |
|
position_ids = position_ids.unsqueeze(0).view(-1, seq_length) |
|
else: |
|
position_ids = position_ids.view(-1, seq_length).long() |
|
|
|
if inputs_embeds is None: |
|
inputs_embeds = self.embed_tokens(input_ids) |
|
|
|
if attention_mask is not None and self._attn_implementation == "flash_attention_2" and use_cache: |
|
is_padding_right = attention_mask[:, -1].sum().item() != batch_size |
|
if is_padding_right: |
|
raise ValueError( |
|
"You are attempting to perform batched generation with padding_side='right'" |
|
" this may lead to unexpected behaviour for Flash Attention version of Jamba. Make sure to " |
|
" call `tokenizer.padding_side = 'left'` before tokenizing the input. " |
|
) |
|
|
|
if self._attn_implementation == "flash_attention_2": |
|
|
|
attention_mask = attention_mask if (attention_mask is not None and 0 in attention_mask) else None |
|
elif self._attn_implementation == "sdpa" and not output_attentions: |
|
|
|
|
|
attention_mask = _prepare_4d_causal_attention_mask_for_sdpa( |
|
attention_mask, |
|
(batch_size, seq_length), |
|
inputs_embeds, |
|
past_key_values_length, |
|
) |
|
else: |
|
|
|
attention_mask = _prepare_4d_causal_attention_mask( |
|
attention_mask, |
|
(batch_size, seq_length), |
|
inputs_embeds, |
|
past_key_values_length, |
|
sliding_window=self.config.sliding_window, |
|
) |
|
|
|
hidden_states = inputs_embeds |
|
|
|
|
|
all_hidden_states = () if output_hidden_states else None |
|
all_self_attns = () if output_attentions else None |
|
all_router_logits = () if output_router_logits else None |
|
next_decoder_cache = None |
|
|
|
for decoder_layer in self.layers: |
|
if output_hidden_states: |
|
all_hidden_states += (hidden_states,) |
|
|
|
if self.gradient_checkpointing and self.training: |
|
layer_outputs = self._gradient_checkpointing_func( |
|
decoder_layer.__call__, |
|
hidden_states, |
|
attention_mask, |
|
position_ids, |
|
past_key_values, |
|
output_attentions, |
|
output_router_logits, |
|
use_cache, |
|
) |
|
else: |
|
layer_outputs = decoder_layer( |
|
hidden_states, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
past_key_value=past_key_values, |
|
output_attentions=output_attentions, |
|
output_router_logits=output_router_logits, |
|
use_cache=use_cache, |
|
) |
|
|
|
hidden_states = layer_outputs[0] |
|
|
|
if use_cache: |
|
next_decoder_cache = layer_outputs[2 if output_attentions else 1] |
|
|
|
if output_attentions: |
|
all_self_attns += (layer_outputs[1],) |
|
|
|
if output_router_logits: |
|
all_router_logits += (layer_outputs[-1],) |
|
|
|
hidden_states = self.final_layernorm(hidden_states) |
|
|
|
|
|
if output_hidden_states: |
|
all_hidden_states += (hidden_states,) |
|
|
|
next_cache = None |
|
if use_cache: |
|
next_cache = next_decoder_cache.to_legacy_cache() if use_legacy_cache else next_decoder_cache |
|
|
|
if not return_dict: |
|
return tuple( |
|
v |
|
for v in [hidden_states, next_cache, all_hidden_states, all_self_attns, all_router_logits] |
|
if v is not None |
|
) |
|
return MoeModelOutputWithPast( |
|
last_hidden_state=hidden_states, |
|
past_key_values=next_cache, |
|
hidden_states=all_hidden_states, |
|
attentions=all_self_attns, |
|
router_logits=all_router_logits, |
|
) |
|
|
|
|
|
|
|
class JambaForCausalLM(JambaPreTrainedModel): |
|
_tied_weights_keys = ["lm_head.weight"] |
|
|
|
def __init__(self, config: JambaConfig): |
|
super().__init__(config) |
|
self.model = JambaModel(config) |
|
self.vocab_size = config.vocab_size |
|
self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False) |
|
self.router_aux_loss_coef = config.router_aux_loss_coef |
|
self.num_experts = config.num_experts |
|
self.num_experts_per_tok = config.num_experts_per_tok |
|
|
|
self.post_init() |
|
|
|
def get_input_embeddings(self): |
|
return self.model.embed_tokens |
|
|
|
def set_input_embeddings(self, value): |
|
self.model.embed_tokens = value |
|
|
|
def get_output_embeddings(self): |
|
return self.lm_head |
|
|
|
def set_output_embeddings(self, new_embeddings): |
|
self.lm_head = new_embeddings |
|
|
|
def set_decoder(self, decoder): |
|
self.model = decoder |
|
|
|
def get_decoder(self): |
|
return self.model |
|
|
|
@add_start_docstrings_to_model_forward(JAMBA_INPUTS_DOCSTRING) |
|
@replace_return_docstrings(output_type=MoeCausalLMOutputWithPast, config_class=_CONFIG_FOR_DOC) |
|
|
|
def forward( |
|
self, |
|
input_ids: torch.LongTensor = None, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_values: Optional[List[torch.FloatTensor]] = None, |
|
inputs_embeds: Optional[torch.FloatTensor] = None, |
|
labels: Optional[torch.LongTensor] = None, |
|
use_cache: Optional[bool] = None, |
|
output_attentions: Optional[bool] = None, |
|
output_hidden_states: Optional[bool] = None, |
|
output_router_logits: Optional[bool] = None, |
|
return_dict: Optional[bool] = None, |
|
calc_logits_for_entire_prompt: Optional[bool] = True, |
|
) -> Union[Tuple, MoeCausalLMOutputWithPast]: |
|
r""" |
|
Args: |
|
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*): |
|
Labels for computing the masked language modeling loss. Indices should either be in `[0, ..., |
|
config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored |
|
(masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`. |
|
|
|
calc_logits_for_entire_prompt (`bool`, *optional*): |
|
Whether or not to calculate the logits for the entire prompt, or just the last token. Only last token |
|
logits are needed for generation, and calculating them only for that token can save memory, |
|
which becomes pretty significant for long sequences. |
|
|
|
Returns: |
|
```""" |
|
|
|
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions |
|
output_router_logits = ( |
|
output_router_logits if output_router_logits is not None else self.config.output_router_logits |
|
) |
|
|
|
output_hidden_states = ( |
|
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states |
|
) |
|
return_dict = return_dict if return_dict is not None else self.config.use_return_dict |
|
|
|
|
|
outputs = self.model( |
|
input_ids=input_ids, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
past_key_values=past_key_values, |
|
inputs_embeds=inputs_embeds, |
|
use_cache=use_cache, |
|
output_attentions=output_attentions, |
|
output_hidden_states=output_hidden_states, |
|
output_router_logits=output_router_logits, |
|
return_dict=return_dict, |
|
) |
|
|
|
hidden_states = outputs[0] |
|
if calc_logits_for_entire_prompt: |
|
logits = self.lm_head(hidden_states) |
|
else: |
|
logits = self.lm_head(hidden_states[..., -1:, :]) |
|
logits = logits.float() |
|
|
|
loss = None |
|
if labels is not None: |
|
|
|
shift_logits = logits[..., :-1, :].contiguous() |
|
shift_labels = labels[..., 1:].contiguous() |
|
|
|
loss_fct = CrossEntropyLoss() |
|
shift_logits = shift_logits.view(-1, self.config.vocab_size) |
|
shift_labels = shift_labels.view(-1) |
|
|
|
shift_labels = shift_labels.to(shift_logits.device) |
|
loss = loss_fct(shift_logits, shift_labels) |
|
|
|
aux_loss = None |
|
if output_router_logits: |
|
aux_loss = load_balancing_loss_func( |
|
outputs.router_logits if return_dict else outputs[-1], |
|
self.num_experts, |
|
self.num_experts_per_tok, |
|
attention_mask, |
|
) |
|
if labels is not None: |
|
loss += self.router_aux_loss_coef * aux_loss.to(loss.device) |
|
|
|
if not return_dict: |
|
output = (logits,) + outputs[1:] |
|
if output_router_logits: |
|
output = (aux_loss,) + output |
|
return (loss,) + output if loss is not None else output |
|
|
|
return MoeCausalLMOutputWithPast( |
|
loss=loss, |
|
aux_loss=aux_loss, |
|
logits=logits, |
|
past_key_values=outputs.past_key_values, |
|
hidden_states=outputs.hidden_states, |
|
attentions=outputs.attentions, |
|
router_logits=outputs.router_logits, |
|
) |
|
|
|
def prepare_inputs_for_generation( |
|
self, |
|
input_ids, |
|
past_key_values=None, |
|
attention_mask=None, |
|
inputs_embeds=None, |
|
output_router_logits=False, |
|
**kwargs, |
|
): |
|
|
|
if past_key_values is not None: |
|
|
|
if isinstance(past_key_values, Tuple): |
|
if past_key_values[self.model._mamba_layer_index][0].shape[2] > 1: |
|
past_key_values = self._convert_to_jamba_cache(past_key_values) |
|
|
|
if isinstance(past_key_values, Cache): |
|
if not isinstance(past_key_values, HybridMambaAttentionDynamicCache): |
|
past_key_values = HybridMambaAttentionDynamicCache.from_legacy_cache( |
|
past_key_values.to_legacy_cache() |
|
) |
|
cache_length = past_key_values.get_seq_length() |
|
past_length = past_key_values.seen_tokens |
|
max_cache_length = past_key_values.get_max_length() |
|
else: |
|
cache_length = past_length = past_key_values[self.model._attn_layer_index][0].shape[2] |
|
max_cache_length = None |
|
|
|
|
|
|
|
|
|
|
|
if attention_mask is not None and attention_mask.shape[1] > input_ids.shape[1]: |
|
input_ids = input_ids[:, -(attention_mask.shape[1] - past_length) :] |
|
|
|
|
|
elif past_length < input_ids.shape[1]: |
|
input_ids = input_ids[:, past_length:] |
|
|
|
|
|
|
|
if ( |
|
max_cache_length is not None |
|
and attention_mask is not None |
|
and cache_length + input_ids.shape[1] > max_cache_length |
|
): |
|
attention_mask = attention_mask[:, -max_cache_length:] |
|
|
|
position_ids = kwargs.get("position_ids", None) |
|
if attention_mask is not None and position_ids is None: |
|
|
|
position_ids = attention_mask.long().cumsum(-1) - 1 |
|
position_ids.masked_fill_(attention_mask == 0, 1) |
|
if past_key_values: |
|
position_ids = position_ids[:, -input_ids.shape[1] :] |
|
|
|
|
|
if inputs_embeds is not None and past_key_values is None: |
|
model_inputs = {"inputs_embeds": inputs_embeds} |
|
else: |
|
model_inputs = {"input_ids": input_ids} |
|
|
|
model_inputs.update( |
|
{ |
|
"position_ids": position_ids, |
|
"past_key_values": past_key_values, |
|
"use_cache": kwargs.get("use_cache"), |
|
"attention_mask": attention_mask, |
|
"output_router_logits": output_router_logits, |
|
"calc_logits_for_entire_prompt": self.config.calc_logits_for_entire_prompt, |
|
} |
|
) |
|
return model_inputs |
|
|
|
@staticmethod |
|
def _reorder_cache(past_key_values, beam_idx): |
|
reordered_past = () |
|
for layer_past in past_key_values: |
|
reordered_past += ( |
|
tuple(past_state.index_select(0, beam_idx.to(past_state.device)) for past_state in layer_past), |
|
) |
|
return reordered_past |
|
|
|
|
|
@add_start_docstrings( |
|
""" |
|
The Jamba Model with a sequence classification head on top (linear layer). |
|
|
|
[`JambaForSequenceClassification`] uses the last token in order to do the classification, as other causal models |
|
(e.g. GPT-2) do. |
|
|
|
Since it does classification on the last token, it requires to know the position of the last token. If a |
|
`pad_token_id` is defined in the configuration, it finds the last token that is not a padding token in each row. If |
|
no `pad_token_id` is defined, it simply takes the last value in each row of the batch. Since it cannot guess the |
|
padding tokens when `inputs_embeds` are passed instead of `input_ids`, it does the same (take the last value in |
|
each row of the batch). |
|
""", |
|
JAMBA_START_DOCSTRING, |
|
) |
|
|
|
class JambaForSequenceClassification(JambaPreTrainedModel): |
|
def __init__(self, config): |
|
super().__init__(config) |
|
self.num_labels = config.num_labels |
|
self.model = JambaModel(config) |
|
self.score = nn.Linear(config.hidden_size, self.num_labels, bias=False) |
|
|
|
|
|
self.post_init() |
|
|
|
def get_input_embeddings(self): |
|
return self.model.embed_tokens |
|
|
|
def set_input_embeddings(self, value): |
|
self.model.embed_tokens = value |
|
|
|
@add_start_docstrings_to_model_forward(JAMBA_INPUTS_DOCSTRING) |
|
def forward( |
|
self, |
|
input_ids: torch.LongTensor = None, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_values: Optional[List[torch.FloatTensor]] = None, |
|
inputs_embeds: Optional[torch.FloatTensor] = None, |
|
labels: Optional[torch.LongTensor] = None, |
|
use_cache: Optional[bool] = None, |
|
output_attentions: Optional[bool] = None, |
|
output_hidden_states: Optional[bool] = None, |
|
return_dict: Optional[bool] = None, |
|
) -> Union[Tuple, SequenceClassifierOutputWithPast]: |
|
r""" |
|
labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*): |
|
Labels for computing the sequence classification/regression loss. Indices should be in `[0, ..., |
|
config.num_labels - 1]`. If `config.num_labels == 1` a regression loss is computed (Mean-Square loss), If |
|
`config.num_labels > 1` a classification loss is computed (Cross-Entropy). |
|
""" |
|
return_dict = return_dict if return_dict is not None else self.config.use_return_dict |
|
|
|
transformer_outputs = self.model( |
|
input_ids, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
past_key_values=past_key_values, |
|
inputs_embeds=inputs_embeds, |
|
use_cache=use_cache, |
|
output_attentions=output_attentions, |
|
output_hidden_states=output_hidden_states, |
|
return_dict=return_dict, |
|
) |
|
hidden_states = transformer_outputs[0] |
|
logits = self.score(hidden_states) |
|
|
|
if input_ids is not None: |
|
batch_size = input_ids.shape[0] |
|
else: |
|
batch_size = inputs_embeds.shape[0] |
|
|
|
if self.config.pad_token_id is None and batch_size != 1: |
|
raise ValueError("Cannot handle batch sizes > 1 if no padding token is defined.") |
|
if self.config.pad_token_id is None: |
|
sequence_lengths = -1 |
|
else: |
|
if input_ids is not None: |
|
|
|
sequence_lengths = torch.eq(input_ids, self.config.pad_token_id).int().argmax(-1) - 1 |
|
sequence_lengths = sequence_lengths % input_ids.shape[-1] |
|
sequence_lengths = sequence_lengths.to(logits.device) |
|
else: |
|
sequence_lengths = -1 |
|
|
|
pooled_logits = logits[torch.arange(batch_size, device=logits.device), sequence_lengths] |
|
|
|
loss = None |
|
if labels is not None: |
|
labels = labels.to(logits.device) |
|
if self.config.problem_type is None: |
|
if self.num_labels == 1: |
|
self.config.problem_type = "regression" |
|
elif self.num_labels > 1 and (labels.dtype == torch.long or labels.dtype == torch.int): |
|
self.config.problem_type = "single_label_classification" |
|
else: |
|
self.config.problem_type = "multi_label_classification" |
|
|
|
if self.config.problem_type == "regression": |
|
loss_fct = MSELoss() |
|
if self.num_labels == 1: |
|
loss = loss_fct(pooled_logits.squeeze(), labels.squeeze()) |
|
else: |
|
loss = loss_fct(pooled_logits, labels) |
|
elif self.config.problem_type == "single_label_classification": |
|
loss_fct = CrossEntropyLoss() |
|
loss = loss_fct(pooled_logits.view(-1, self.num_labels), labels.view(-1)) |
|
elif self.config.problem_type == "multi_label_classification": |
|
loss_fct = BCEWithLogitsLoss() |
|
loss = loss_fct(pooled_logits, labels) |
|
if not return_dict: |
|
output = (pooled_logits,) + transformer_outputs[1:] |
|
return ((loss,) + output) if loss is not None else output |
|
|
|
return SequenceClassifierOutputWithPast( |
|
loss=loss, |
|
logits=pooled_logits, |
|
past_key_values=transformer_outputs.past_key_values, |
|
hidden_states=transformer_outputs.hidden_states, |
|
attentions=transformer_outputs.attentions, |
|
) |
|
|