Commit
•
e023a84
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Parent(s):
9eceafb
Convert ReplitLM to MPT (#16)
Browse files- Convert ReplitLM to MPT (2635241d5b35bf63b8652513c212f645b78b1572)
Co-authored-by: Madhav <madhavatreplit@users.noreply.huggingface.co>
- README.md +1 -6
- adapt_tokenizer.py +41 -0
- attention.py +144 -275
- blocks.py +41 -0
- config.json +31 -25
- configuration_mpt.py +118 -0
- generation_config.json +1 -1
- hf_prefixlm_converter.py +415 -0
- meta_init_context.py +94 -0
- modeling_mpt.py +291 -0
- norm.py +56 -0
- param_init_fns.py +65 -348
- replit_lm_tokenizer.py +15 -57
- special_tokens_map.json +4 -4
- tokenizer_config.json +17 -17
README.md
CHANGED
@@ -173,9 +173,4 @@ Note that as with all code generation models, post-processing of the generated c
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- stop generation when the EOS token is encountered
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- remove trailing whitespaces
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- set `max_tokens` to a reasonable value based on your completion use case
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- truncate generation to stop words such as `return`, `def`, "```", "`\n\n\n`" to avoid generating incomplete code when `max_tokens` is larger than the length of the expected generated code.
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## Model Hash
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5bc28ce32c6f9aec935ead7b60ea1c46
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- stop generation when the EOS token is encountered
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- remove trailing whitespaces
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- set `max_tokens` to a reasonable value based on your completion use case
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+
- truncate generation to stop words such as `return`, `def`, "```", "`\n\n\n`" to avoid generating incomplete code when `max_tokens` is larger than the length of the expected generated code.
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adapt_tokenizer.py
ADDED
@@ -0,0 +1,41 @@
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from typing import Union
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from transformers import AutoTokenizer, PreTrainedTokenizer, PreTrainedTokenizerFast
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Tokenizer = Union[PreTrainedTokenizer, PreTrainedTokenizerFast]
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NUM_SENTINEL_TOKENS: int = 100
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def adapt_tokenizer_for_denoising(tokenizer: Tokenizer):
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"""Adds sentinel tokens and padding token (if missing).
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Expands the tokenizer vocabulary to include sentinel tokens
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used in mixture-of-denoiser tasks as well as a padding token.
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All added tokens are added as special tokens. No tokens are
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added if sentinel tokens and padding token already exist.
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"""
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sentinels_to_add = [f'<extra_id_{i}>' for i in range(NUM_SENTINEL_TOKENS)]
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tokenizer.add_tokens(sentinels_to_add, special_tokens=True)
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if tokenizer.pad_token is None:
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tokenizer.add_tokens('<pad>', special_tokens=True)
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tokenizer.pad_token = '<pad>'
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assert tokenizer.pad_token_id is not None
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sentinels = ''.join([f'<extra_id_{i}>' for i in range(NUM_SENTINEL_TOKENS)])
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_sentinel_token_ids = tokenizer(sentinels, add_special_tokens=False).input_ids
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tokenizer.sentinel_token_ids = _sentinel_token_ids
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class AutoTokenizerForMOD(AutoTokenizer):
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"""AutoTokenizer + Adaptation for MOD.
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A simple wrapper around AutoTokenizer to make instantiating
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an MOD-adapted tokenizer a bit easier.
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MOD-adapted tokenizers have sentinel tokens (e.g., <extra_id_0>),
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a padding token, and a property to get the token ids of the
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sentinel tokens.
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"""
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@classmethod
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def from_pretrained(cls, *args, **kwargs):
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"""See `AutoTokenizer.from_pretrained` docstring."""
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tokenizer = super().from_pretrained(*args, **kwargs)
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adapt_tokenizer_for_denoising(tokenizer)
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return tokenizer
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attention.py
CHANGED
@@ -1,80 +1,39 @@
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# Copyright 2022 MosaicML Examples authors
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# SPDX-License-Identifier: Apache-2.0
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"""Attention layers."""
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-
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import math
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import warnings
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from typing import Optional
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-
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import torch
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from einops import rearrange
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from torch import nn
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-
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-
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-
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def _reset_is_causal(num_query_tokens: int, num_key_tokens: int,
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original_is_causal: bool):
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if original_is_causal and num_query_tokens != num_key_tokens:
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if num_query_tokens != 1:
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raise NotImplementedError(
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'ReplitLM does not support query and key with different number of tokens, unless number of query tokens is 1.'
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)
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else:
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return False
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return original_is_causal
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-
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-
def scaled_multihead_dot_product_attention(
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query,
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key,
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value,
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n_heads,
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softmax_scale=None,
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attn_bias=None,
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key_padding_mask=None,
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is_causal=False,
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dropout_p=0.0,
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training=False,
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needs_weights=False,
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):
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-
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q = rearrange(query, 'b s (h d) -> b h s d', h=n_heads)
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k = rearrange(key, 'b s (h d) -> b h d s', h=
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v = rearrange(value, 'b s (h d) -> b h s d', h=n_heads)
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-
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min_val = torch.finfo(q.dtype).min
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-
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b, _, s_q, d = q.shape
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s_k = k.size(-1)
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-
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if softmax_scale is None:
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softmax_scale = 1 / math.sqrt(d)
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-
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attn_weight = q.matmul(k) * softmax_scale
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-
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if attn_bias is not None:
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-
if (attn_bias.size(-1) != 1 and
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-
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attn_bias.size(-2) != s_q):
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raise RuntimeError(
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f'attn_bias (shape: {attn_bias.shape}) is expected to broadcast to shape: {attn_weight.shape}.'
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)
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attn_weight = attn_weight + attn_bias
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-
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if key_padding_mask is not None:
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if attn_bias is not None:
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warnings.warn(
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-
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-
'and applying it within the attention module can cause ' +
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'unneccessary computation/memory usage. Consider integrating ' +
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'into attn_bias once and passing that to each attention ' +
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'module instead.'
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)
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attn_weight = attn_weight.masked_fill(
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~key_padding_mask.view((b, 1, 1, s_k)), min_val)
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-
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if is_causal:
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s = max(s_q, s_k)
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causal_mask = attn_weight.new_ones(s, s, dtype=torch.float16)
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@@ -82,156 +41,76 @@ def scaled_multihead_dot_product_attention(
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causal_mask = causal_mask.to(torch.bool)
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causal_mask = ~causal_mask
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causal_mask = causal_mask[-s_q:, -s_k:]
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-
attn_weight = attn_weight.masked_fill(causal_mask.view(1, 1, s_q, s_k),
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min_val)
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attn_weight = torch.softmax(attn_weight, dim=-1)
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-
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if dropout_p:
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-
attn_weight = torch.nn.functional.dropout(attn_weight,
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p=dropout_p,
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training=training,
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inplace=True)
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-
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out = attn_weight.matmul(v)
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out = rearrange(out, 'b h s d -> b s (h d)')
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-
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if needs_weights:
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return out, attn_weight
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return out, None
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-
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def check_valid_inputs(*tensors, valid_dtypes=[torch.float16, torch.bfloat16]):
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for tensor in tensors:
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if tensor.dtype not in valid_dtypes:
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raise TypeError(f'{tensor.dtype
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if not tensor.is_cuda:
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raise TypeError(
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f'Inputs must be cuda tensors ({tensor.is_cuda=}).')
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-
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-
def flash_attn_fn(
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query,
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key,
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value,
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n_heads,
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softmax_scale=None,
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attn_bias=None,
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key_padding_mask=None,
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is_causal=False,
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dropout_p=0.0,
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training=False,
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needs_weights=False,
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):
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try:
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from flash_attn import bert_padding, flash_attn_interface
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except:
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raise RuntimeError('Please install
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-
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check_valid_inputs(query, key, value)
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-
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if attn_bias is not None:
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raise NotImplementedError(f'attn_bias not implemented for flash attn.')
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-
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batch_size, seqlen = query.shape[:2]
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-
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if key_padding_mask is None:
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key_padding_mask = torch.ones_like(key[:, :, 0], dtype=torch.bool)
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query_padding_mask = key_padding_mask[:, -query.size(1):]
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-
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-
query_unpad, indices_q, cu_seqlens_q, max_seqlen_q = bert_padding.unpad_input(
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query, query_padding_mask)
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query_unpad = rearrange(query_unpad, 'nnz (h d) -> nnz h d', h=n_heads)
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-
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key_unpad
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-
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-
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-
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-
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-
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-
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dropout_p = dropout_p if training else 0.0
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-
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reset_is_causal = _reset_is_causal(query.size(1), key.size(1), is_causal)
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-
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query_unpad,
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key_unpad,
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value_unpad,
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cu_seqlens_q,
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cu_seqlens_k,
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max_seqlen_q,
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max_seqlen_k,
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dropout_p,
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softmax_scale=softmax_scale,
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causal=reset_is_causal,
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return_attn_probs=needs_weights)
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-
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output = bert_padding.pad_input(
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rearrange(output_unpad, 'nnz h d -> nnz (h d)'), indices_q, batch_size,
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seqlen)
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return output, None
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-
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-
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-
def triton_flash_attn_fn(
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query,
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key,
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value,
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n_heads,
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-
softmax_scale=None,
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attn_bias=None,
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key_padding_mask=None,
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-
is_causal=False,
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dropout_p=0.0,
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-
training=False,
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needs_weights=False,
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-
):
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try:
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from flash_attn import flash_attn_triton
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except:
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-
raise RuntimeError(
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'Please install flash_attn==0.2.8 and triton==2.0.0.dev20221202.')
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-
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check_valid_inputs(query, key, value)
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-
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197 |
if dropout_p:
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-
raise NotImplementedError(
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199 |
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f'Dropout not implemented for attn_impl: triton.')
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200 |
-
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if needs_weights:
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202 |
-
raise NotImplementedError(
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203 |
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f'attn_impl: triton cannot return attn weights.')
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204 |
-
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205 |
if key_padding_mask is not None:
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206 |
-
warnings.warn(
|
207 |
-
|
208 |
-
'and applying it within the attention module can cause ' +
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209 |
-
'unnecessary computation/memory usage. Consider integrating ' +
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-
'into attn_bias once and passing that to each attention ' +
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-
'module instead.'
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-
)
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213 |
-
b_size, s_k = key_padding_mask.shape[:2]
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214 |
-
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215 |
if attn_bias is None:
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216 |
attn_bias = query.new_zeros(b_size, 1, 1, s_k)
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217 |
-
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218 |
-
attn_bias = attn_bias.masked_fill(
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~key_padding_mask.view((b_size, 1, 1, s_k)),
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220 |
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torch.finfo(query.dtype).min)
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-
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query = rearrange(query, 'b s (h d) -> b s h d', h=n_heads)
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-
key = rearrange(key, 'b s (h d) -> b s h d', h=n_heads)
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value = rearrange(value, 'b s (h d) -> b s h d', h=n_heads)
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-
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reset_is_causal = _reset_is_causal(query.size(1), key.size(1), is_causal)
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-
attn_output = flash_attn_triton.flash_attn_func(query, key, value,
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attn_bias, reset_is_causal,
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-
softmax_scale)
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-
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output = attn_output.view(*attn_output.shape[:2], -1)
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232 |
-
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-
return output, None
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-
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class MultiheadAttention(nn.Module):
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"""Multi-head self attention.
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@@ -240,115 +119,121 @@ class MultiheadAttention(nn.Module):
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additive bias.
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"""
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243 |
-
def __init__(
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self,
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d_model: int,
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n_heads: int,
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247 |
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attn_impl: str = 'triton',
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attn_clip_qkv: Optional[float] = None,
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attn_qk_ln: bool = False,
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softmax_scale: Optional[float] = None,
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attn_pdrop: float = 0.0,
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low_precision_layernorm: bool = False,
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device: Optional[str] = None,
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-
):
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255 |
super().__init__()
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-
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self.attn_impl = attn_impl
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-
self.clip_qkv =
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-
self.
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-
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self.d_model = d_model
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self.n_heads = n_heads
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self.softmax_scale = softmax_scale
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if self.softmax_scale is None:
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265 |
self.softmax_scale = 1 / math.sqrt(self.d_model / self.n_heads)
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self.attn_dropout_p = attn_pdrop
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267 |
-
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268 |
self.Wqkv = nn.Linear(self.d_model, 3 * self.d_model, device=device)
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269 |
-
# for param init fn; enables shape based init of fused layers
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270 |
fuse_splits = (d_model, 2 * d_model)
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271 |
-
self.Wqkv._fused = (0, fuse_splits)
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272 |
-
|
273 |
-
if self.attn_qk_ln:
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274 |
layernorm_class = LPLayerNorm if low_precision_layernorm else nn.LayerNorm
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275 |
self.q_ln = layernorm_class(self.d_model, device=device)
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276 |
self.k_ln = layernorm_class(self.d_model, device=device)
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277 |
-
|
278 |
if self.attn_impl == 'flash':
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279 |
self.attn_fn = flash_attn_fn
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280 |
elif self.attn_impl == 'triton':
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281 |
self.attn_fn = triton_flash_attn_fn
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282 |
-
|
283 |
-
'While `attn_impl: triton` can be faster than `attn_impl: flash` ' +
|
284 |
-
'it uses more memory. When training larger models this can trigger ' +
|
285 |
-
'alloc retries which hurts performance. If encountered, we recommend ' +
|
286 |
-
'using `attn_impl: flash` if your model does not use `alibi` or `prefix_lm`.')
|
287 |
elif self.attn_impl == 'torch':
|
288 |
self.attn_fn = scaled_multihead_dot_product_attention
|
289 |
-
if torch.cuda.is_available():
|
290 |
-
warnings.warn(
|
291 |
-
'Using `attn_impl: torch`. If your model does not use `alibi` or ' +
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292 |
-
'`prefix_lm` we recommend using `attn_impl: flash` otherwise ' +
|
293 |
-
'we recommend using `attn_impl: triton`.'
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294 |
-
)
|
295 |
else:
|
296 |
-
raise ValueError(f'{attn_impl
|
297 |
-
|
298 |
self.out_proj = nn.Linear(self.d_model, self.d_model, device=device)
|
299 |
-
self.out_proj._is_residual = True
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300 |
|
301 |
-
def forward(self,
|
302 |
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x,
|
303 |
-
past_key_value=None,
|
304 |
-
attn_bias=None,
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305 |
-
attention_mask=None,
|
306 |
-
is_causal=True,
|
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-
needs_weights=False):
|
308 |
qkv = self.Wqkv(x)
|
309 |
-
|
310 |
if self.clip_qkv:
|
311 |
qkv.clamp_(min=-self.clip_qkv, max=self.clip_qkv)
|
312 |
-
|
313 |
-
query, key, value = qkv.chunk(3, dim=2)
|
314 |
-
|
315 |
key_padding_mask = attention_mask
|
316 |
-
|
317 |
-
if self.attn_qk_ln:
|
318 |
-
# Applying layernorm to qk
|
319 |
dtype = query.dtype
|
320 |
query = self.q_ln(query).to(dtype)
|
321 |
key = self.k_ln(key).to(dtype)
|
322 |
-
|
323 |
if past_key_value is not None:
|
324 |
if len(past_key_value) != 0:
|
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key = torch.cat([past_key_value[0], key], dim=1)
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value = torch.cat([past_key_value[1], value], dim=1)
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-
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past_key_value = (key, value)
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-
|
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if attn_bias is not None:
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attn_bias = attn_bias[:, :, -query.size(1):, -key.size(1):]
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key,
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value,
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self.n_heads,
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softmax_scale=self.softmax_scale,
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attn_bias=attn_bias,
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key_padding_mask=key_padding_mask,
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is_causal=is_causal,
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dropout_p=self.attn_dropout_p,
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training=self.training,
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needs_weights=needs_weights,
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-
)
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|
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-
def
|
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-
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if attn_impl == 'flash':
|
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return None
|
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elif attn_impl in ['torch', 'triton']:
|
@@ -360,50 +245,34 @@ def attn_bias_shape(attn_impl, n_heads, seq_len, alibi, prefix_lm, causal,
|
|
360 |
return (1, 1, seq_len, seq_len)
|
361 |
return None
|
362 |
else:
|
363 |
-
raise ValueError(f'{attn_impl
|
364 |
-
|
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|
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-
def
|
367 |
-
attn_bias,
|
368 |
-
n_heads,
|
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seq_len,
|
370 |
-
causal=False,
|
371 |
-
alibi=False,
|
372 |
-
alibi_bias_max=8):
|
373 |
if attn_impl == 'flash':
|
374 |
return None
|
375 |
elif attn_impl in ['torch', 'triton']:
|
376 |
if alibi:
|
377 |
-
|
378 |
-
|
379 |
-
attn_bias = attn_bias.add(
|
380 |
-
alibi_bias(n_heads,
|
381 |
-
seq_len,
|
382 |
-
full=not causal,
|
383 |
-
alibi_bias_max=alibi_bias_max,
|
384 |
-
device=device,
|
385 |
-
dtype=dtype))
|
386 |
return attn_bias
|
387 |
else:
|
388 |
-
raise ValueError(f'{attn_impl
|
389 |
-
|
390 |
-
|
391 |
-
|
392 |
-
|
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-
|
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-
|
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-
|
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-
|
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-
|
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-
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|
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if full:
|
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-
|
401 |
-
# otherwise the mask is 1 x Heads x 1 x SeqLen (which is broadcast to the appropriate size)
|
402 |
-
alibi_bias = alibi_bias - torch.arange(
|
403 |
-
1 - seq_len, 1, dtype=dtype, device=device).view(1, 1, seq_len, 1)
|
404 |
alibi_bias = alibi_bias.abs().mul(-1)
|
405 |
-
|
406 |
-
|
407 |
-
|
408 |
-
|
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-
return alibi_bias
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|
1 |
"""Attention layers."""
|
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|
2 |
import math
|
3 |
import warnings
|
4 |
from typing import Optional
|
|
|
5 |
import torch
|
6 |
+
import torch.nn as nn
|
7 |
from einops import rearrange
|
8 |
from torch import nn
|
9 |
+
from .norm import LPLayerNorm
|
10 |
|
11 |
+
def _reset_is_causal(num_query_tokens: int, num_key_tokens: int, original_is_causal: bool):
|
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|
12 |
if original_is_causal and num_query_tokens != num_key_tokens:
|
13 |
if num_query_tokens != 1:
|
14 |
+
raise NotImplementedError('MPT does not support query and key with different number of tokens, unless number of query tokens is 1.')
|
|
|
|
|
15 |
else:
|
16 |
return False
|
17 |
return original_is_causal
|
18 |
|
19 |
+
def scaled_multihead_dot_product_attention(query, key, value, n_heads, softmax_scale=None, attn_bias=None, key_padding_mask=None, is_causal=False, dropout_p=0.0, training=False, needs_weights=False, multiquery=False):
|
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|
20 |
q = rearrange(query, 'b s (h d) -> b h s d', h=n_heads)
|
21 |
+
k = rearrange(key, 'b s (h d) -> b h d s', h=1 if multiquery else n_heads)
|
22 |
+
v = rearrange(value, 'b s (h d) -> b h s d', h=1 if multiquery else n_heads)
|
|
|
23 |
min_val = torch.finfo(q.dtype).min
|
24 |
+
(b, _, s_q, d) = q.shape
|
|
|
25 |
s_k = k.size(-1)
|
|
|
26 |
if softmax_scale is None:
|
27 |
softmax_scale = 1 / math.sqrt(d)
|
|
|
28 |
attn_weight = q.matmul(k) * softmax_scale
|
|
|
29 |
if attn_bias is not None:
|
30 |
+
if attn_bias.size(-1) != 1 and attn_bias.size(-1) != s_k or (attn_bias.size(-2) != 1 and attn_bias.size(-2) != s_q):
|
31 |
+
raise RuntimeError(f'attn_bias (shape: {attn_bias.shape}) is expected to broadcast to shape: {attn_weight.shape}.')
|
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|
32 |
attn_weight = attn_weight + attn_bias
|
|
|
33 |
if key_padding_mask is not None:
|
34 |
if attn_bias is not None:
|
35 |
+
warnings.warn('Propogating key_padding_mask to the attention module ' + 'and applying it within the attention module can cause ' + 'unneccessary computation/memory usage. Consider integrating ' + 'into attn_bias once and passing that to each attention ' + 'module instead.')
|
36 |
+
attn_weight = attn_weight.masked_fill(~key_padding_mask.view((b, 1, 1, s_k)), min_val)
|
|
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|
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|
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|
|
37 |
if is_causal:
|
38 |
s = max(s_q, s_k)
|
39 |
causal_mask = attn_weight.new_ones(s, s, dtype=torch.float16)
|
41 |
causal_mask = causal_mask.to(torch.bool)
|
42 |
causal_mask = ~causal_mask
|
43 |
causal_mask = causal_mask[-s_q:, -s_k:]
|
44 |
+
attn_weight = attn_weight.masked_fill(causal_mask.view(1, 1, s_q, s_k), min_val)
|
|
|
|
|
45 |
attn_weight = torch.softmax(attn_weight, dim=-1)
|
|
|
46 |
if dropout_p:
|
47 |
+
attn_weight = torch.nn.functional.dropout(attn_weight, p=dropout_p, training=training, inplace=True)
|
|
|
|
|
|
|
|
|
48 |
out = attn_weight.matmul(v)
|
49 |
out = rearrange(out, 'b h s d -> b s (h d)')
|
|
|
50 |
if needs_weights:
|
51 |
+
return (out, attn_weight)
|
52 |
+
return (out, None)
|
|
|
53 |
|
54 |
def check_valid_inputs(*tensors, valid_dtypes=[torch.float16, torch.bfloat16]):
|
55 |
for tensor in tensors:
|
56 |
if tensor.dtype not in valid_dtypes:
|
57 |
+
raise TypeError(f'tensor.dtype={tensor.dtype!r} must be in valid_dtypes={valid_dtypes!r}.')
|
58 |
if not tensor.is_cuda:
|
59 |
+
raise TypeError(f'Inputs must be cuda tensors (tensor.is_cuda={tensor.is_cuda!r}).')
|
|
|
|
|
60 |
|
61 |
+
def flash_attn_fn(query, key, value, n_heads, softmax_scale=None, attn_bias=None, key_padding_mask=None, is_causal=False, dropout_p=0.0, training=False, needs_weights=False, multiquery=False):
|
|
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|
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|
|
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|
|
|
|
|
62 |
try:
|
63 |
from flash_attn import bert_padding, flash_attn_interface
|
64 |
except:
|
65 |
+
raise RuntimeError('Please install flash-attn==1.0.3.post0')
|
|
|
66 |
check_valid_inputs(query, key, value)
|
|
|
67 |
if attn_bias is not None:
|
68 |
raise NotImplementedError(f'attn_bias not implemented for flash attn.')
|
69 |
+
(batch_size, seqlen) = query.shape[:2]
|
|
|
|
|
70 |
if key_padding_mask is None:
|
71 |
key_padding_mask = torch.ones_like(key[:, :, 0], dtype=torch.bool)
|
72 |
query_padding_mask = key_padding_mask[:, -query.size(1):]
|
73 |
+
(query_unpad, indices_q, cu_seqlens_q, max_seqlen_q) = bert_padding.unpad_input(query, query_padding_mask)
|
|
|
|
|
74 |
query_unpad = rearrange(query_unpad, 'nnz (h d) -> nnz h d', h=n_heads)
|
75 |
+
(key_unpad, _, cu_seqlens_k, max_seqlen_k) = bert_padding.unpad_input(key, key_padding_mask)
|
76 |
+
key_unpad = rearrange(key_unpad, 'nnz (h d) -> nnz h d', h=1 if multiquery else n_heads)
|
77 |
+
(value_unpad, _, _, _) = bert_padding.unpad_input(value, key_padding_mask)
|
78 |
+
value_unpad = rearrange(value_unpad, 'nnz (h d) -> nnz h d', h=1 if multiquery else n_heads)
|
79 |
+
if multiquery:
|
80 |
+
key_unpad = key_unpad.expand(key_unpad.size(0), n_heads, key_unpad.size(-1))
|
81 |
+
value_unpad = value_unpad.expand(value_unpad.size(0), n_heads, value_unpad.size(-1))
|
|
|
82 |
dropout_p = dropout_p if training else 0.0
|
|
|
83 |
reset_is_causal = _reset_is_causal(query.size(1), key.size(1), is_causal)
|
84 |
+
output_unpad = flash_attn_interface.flash_attn_unpadded_func(query_unpad, key_unpad, value_unpad, cu_seqlens_q, cu_seqlens_k, max_seqlen_q, max_seqlen_k, dropout_p, softmax_scale=softmax_scale, causal=reset_is_causal, return_attn_probs=needs_weights)
|
85 |
+
output = bert_padding.pad_input(rearrange(output_unpad, 'nnz h d -> nnz (h d)'), indices_q, batch_size, seqlen)
|
86 |
+
return (output, None)
|
87 |
|
88 |
+
def triton_flash_attn_fn(query, key, value, n_heads, softmax_scale=None, attn_bias=None, key_padding_mask=None, is_causal=False, dropout_p=0.0, training=False, needs_weights=False, multiquery=False):
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
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|
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|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
89 |
try:
|
90 |
+
from flash_attn import flash_attn_triton
|
91 |
except:
|
92 |
+
raise RuntimeError('Please install flash-attn==1.0.3.post0 and triton==2.0.0.dev20221202')
|
|
|
|
|
93 |
check_valid_inputs(query, key, value)
|
|
|
94 |
if dropout_p:
|
95 |
+
raise NotImplementedError(f'Dropout not implemented for attn_impl: triton.')
|
|
|
|
|
96 |
if needs_weights:
|
97 |
+
raise NotImplementedError(f'attn_impl: triton cannot return attn weights.')
|
|
|
|
|
98 |
if key_padding_mask is not None:
|
99 |
+
warnings.warn('Propagating key_padding_mask to the attention module ' + 'and applying it within the attention module can cause ' + 'unnecessary computation/memory usage. Consider integrating ' + 'into attn_bias once and passing that to each attention ' + 'module instead.')
|
100 |
+
(b_size, s_k) = key_padding_mask.shape[:2]
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
101 |
if attn_bias is None:
|
102 |
attn_bias = query.new_zeros(b_size, 1, 1, s_k)
|
103 |
+
attn_bias = attn_bias.masked_fill(~key_padding_mask.view((b_size, 1, 1, s_k)), torch.finfo(query.dtype).min)
|
|
|
|
|
|
|
|
|
104 |
query = rearrange(query, 'b s (h d) -> b s h d', h=n_heads)
|
105 |
+
key = rearrange(key, 'b s (h d) -> b s h d', h=1 if multiquery else n_heads)
|
106 |
+
value = rearrange(value, 'b s (h d) -> b s h d', h=1 if multiquery else n_heads)
|
107 |
+
if multiquery:
|
108 |
+
key = key.expand(*key.shape[:2], n_heads, key.size(-1))
|
109 |
+
value = value.expand(*value.shape[:2], n_heads, value.size(-1))
|
110 |
reset_is_causal = _reset_is_causal(query.size(1), key.size(1), is_causal)
|
111 |
+
attn_output = flash_attn_triton.flash_attn_func(query, key, value, attn_bias, reset_is_causal, softmax_scale)
|
|
|
|
|
|
|
112 |
output = attn_output.view(*attn_output.shape[:2], -1)
|
113 |
+
return (output, None)
|
|
|
|
|
114 |
|
115 |
class MultiheadAttention(nn.Module):
|
116 |
"""Multi-head self attention.
|
119 |
additive bias.
|
120 |
"""
|
121 |
|
122 |
+
def __init__(self, d_model: int, n_heads: int, attn_impl: str='triton', clip_qkv: Optional[float]=None, qk_ln: bool=False, softmax_scale: Optional[float]=None, attn_pdrop: float=0.0, low_precision_layernorm: bool=False, verbose: int=0, device: Optional[str]=None):
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
123 |
super().__init__()
|
|
|
124 |
self.attn_impl = attn_impl
|
125 |
+
self.clip_qkv = clip_qkv
|
126 |
+
self.qk_ln = qk_ln
|
|
|
127 |
self.d_model = d_model
|
128 |
self.n_heads = n_heads
|
129 |
self.softmax_scale = softmax_scale
|
130 |
if self.softmax_scale is None:
|
131 |
self.softmax_scale = 1 / math.sqrt(self.d_model / self.n_heads)
|
132 |
self.attn_dropout_p = attn_pdrop
|
|
|
133 |
self.Wqkv = nn.Linear(self.d_model, 3 * self.d_model, device=device)
|
|
|
134 |
fuse_splits = (d_model, 2 * d_model)
|
135 |
+
self.Wqkv._fused = (0, fuse_splits)
|
136 |
+
if self.qk_ln:
|
|
|
137 |
layernorm_class = LPLayerNorm if low_precision_layernorm else nn.LayerNorm
|
138 |
self.q_ln = layernorm_class(self.d_model, device=device)
|
139 |
self.k_ln = layernorm_class(self.d_model, device=device)
|
|
|
140 |
if self.attn_impl == 'flash':
|
141 |
self.attn_fn = flash_attn_fn
|
142 |
elif self.attn_impl == 'triton':
|
143 |
self.attn_fn = triton_flash_attn_fn
|
144 |
+
if verbose:
|
145 |
+
warnings.warn('While `attn_impl: triton` can be faster than `attn_impl: flash` ' + 'it uses more memory. When training larger models this can trigger ' + 'alloc retries which hurts performance. If encountered, we recommend ' + 'using `attn_impl: flash` if your model does not use `alibi` or `prefix_lm`.')
|
|
|
|
|
|
|
146 |
elif self.attn_impl == 'torch':
|
147 |
self.attn_fn = scaled_multihead_dot_product_attention
|
148 |
+
if torch.cuda.is_available() and verbose:
|
149 |
+
warnings.warn('Using `attn_impl: torch`. If your model does not use `alibi` or ' + '`prefix_lm` we recommend using `attn_impl: flash` otherwise ' + 'we recommend using `attn_impl: triton`.')
|
|
|
|
|
|
|
|
|
150 |
else:
|
151 |
+
raise ValueError(f'attn_impl={attn_impl!r} is an invalid setting.')
|
|
|
152 |
self.out_proj = nn.Linear(self.d_model, self.d_model, device=device)
|
153 |
+
self.out_proj._is_residual = True
|
154 |
|
155 |
+
def forward(self, x, past_key_value=None, attn_bias=None, attention_mask=None, is_causal=True, needs_weights=False):
|
|
|
|
|
|
|
|
|
|
|
|
|
156 |
qkv = self.Wqkv(x)
|
|
|
157 |
if self.clip_qkv:
|
158 |
qkv.clamp_(min=-self.clip_qkv, max=self.clip_qkv)
|
159 |
+
(query, key, value) = qkv.chunk(3, dim=2)
|
|
|
|
|
160 |
key_padding_mask = attention_mask
|
161 |
+
if self.qk_ln:
|
|
|
|
|
162 |
dtype = query.dtype
|
163 |
query = self.q_ln(query).to(dtype)
|
164 |
key = self.k_ln(key).to(dtype)
|
|
|
165 |
if past_key_value is not None:
|
166 |
if len(past_key_value) != 0:
|
167 |
key = torch.cat([past_key_value[0], key], dim=1)
|
168 |
value = torch.cat([past_key_value[1], value], dim=1)
|
|
|
169 |
past_key_value = (key, value)
|
|
|
170 |
if attn_bias is not None:
|
171 |
attn_bias = attn_bias[:, :, -query.size(1):, -key.size(1):]
|
172 |
+
(context, attn_weights) = self.attn_fn(query, key, value, self.n_heads, softmax_scale=self.softmax_scale, attn_bias=attn_bias, key_padding_mask=key_padding_mask, is_causal=is_causal, dropout_p=self.attn_dropout_p, training=self.training, needs_weights=needs_weights)
|
173 |
+
return (self.out_proj(context), attn_weights, past_key_value)
|
174 |
|
175 |
+
class MultiQueryAttention(nn.Module):
|
176 |
+
"""Multi-Query self attention.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
177 |
|
178 |
+
Using torch or triton attention implemetation enables user to also use
|
179 |
+
additive bias.
|
180 |
+
"""
|
181 |
|
182 |
+
def __init__(self, d_model: int, n_heads: int, attn_impl: str='triton', clip_qkv: Optional[float]=None, qk_ln: bool=False, softmax_scale: Optional[float]=None, attn_pdrop: float=0.0, low_precision_layernorm: bool=False, verbose: int=0, device: Optional[str]=None):
|
183 |
+
super().__init__()
|
184 |
+
self.attn_impl = attn_impl
|
185 |
+
self.clip_qkv = clip_qkv
|
186 |
+
self.qk_ln = qk_ln
|
187 |
+
self.d_model = d_model
|
188 |
+
self.n_heads = n_heads
|
189 |
+
self.head_dim = d_model // n_heads
|
190 |
+
self.softmax_scale = softmax_scale
|
191 |
+
if self.softmax_scale is None:
|
192 |
+
self.softmax_scale = 1 / math.sqrt(self.head_dim)
|
193 |
+
self.attn_dropout_p = attn_pdrop
|
194 |
+
self.Wqkv = nn.Linear(d_model, d_model + 2 * self.head_dim, device=device)
|
195 |
+
fuse_splits = (d_model, d_model + self.head_dim)
|
196 |
+
self.Wqkv._fused = (0, fuse_splits)
|
197 |
+
if self.qk_ln:
|
198 |
+
layernorm_class = LPLayerNorm if low_precision_layernorm else nn.LayerNorm
|
199 |
+
self.q_ln = layernorm_class(d_model, device=device)
|
200 |
+
self.k_ln = layernorm_class(self.head_dim, device=device)
|
201 |
+
if self.attn_impl == 'flash':
|
202 |
+
self.attn_fn = flash_attn_fn
|
203 |
+
elif self.attn_impl == 'triton':
|
204 |
+
self.attn_fn = triton_flash_attn_fn
|
205 |
+
if verbose:
|
206 |
+
warnings.warn('While `attn_impl: triton` can be faster than `attn_impl: flash` ' + 'it uses more memory. When training larger models this can trigger ' + 'alloc retries which hurts performance. If encountered, we recommend ' + 'using `attn_impl: flash` if your model does not use `alibi` or `prefix_lm`.')
|
207 |
+
elif self.attn_impl == 'torch':
|
208 |
+
self.attn_fn = scaled_multihead_dot_product_attention
|
209 |
+
if torch.cuda.is_available() and verbose:
|
210 |
+
warnings.warn('Using `attn_impl: torch`. If your model does not use `alibi` or ' + '`prefix_lm` we recommend using `attn_impl: flash` otherwise ' + 'we recommend using `attn_impl: triton`.')
|
211 |
+
else:
|
212 |
+
raise ValueError(f'attn_impl={attn_impl!r} is an invalid setting.')
|
213 |
+
self.out_proj = nn.Linear(self.d_model, self.d_model, device=device)
|
214 |
+
self.out_proj._is_residual = True
|
215 |
|
216 |
+
def forward(self, x, past_key_value=None, attn_bias=None, attention_mask=None, is_causal=True, needs_weights=False):
|
217 |
+
qkv = self.Wqkv(x)
|
218 |
+
if self.clip_qkv:
|
219 |
+
qkv.clamp_(min=-self.clip_qkv, max=self.clip_qkv)
|
220 |
+
(query, key, value) = qkv.split([self.d_model, self.head_dim, self.head_dim], dim=2)
|
221 |
+
key_padding_mask = attention_mask
|
222 |
+
if self.qk_ln:
|
223 |
+
dtype = query.dtype
|
224 |
+
query = self.q_ln(query).to(dtype)
|
225 |
+
key = self.k_ln(key).to(dtype)
|
226 |
+
if past_key_value is not None:
|
227 |
+
if len(past_key_value) != 0:
|
228 |
+
key = torch.cat([past_key_value[0], key], dim=1)
|
229 |
+
value = torch.cat([past_key_value[1], value], dim=1)
|
230 |
+
past_key_value = (key, value)
|
231 |
+
if attn_bias is not None:
|
232 |
+
attn_bias = attn_bias[:, :, -query.size(1):, -key.size(1):]
|
233 |
+
(context, attn_weights) = self.attn_fn(query, key, value, self.n_heads, softmax_scale=self.softmax_scale, attn_bias=attn_bias, key_padding_mask=key_padding_mask, is_causal=is_causal, dropout_p=self.attn_dropout_p, training=self.training, needs_weights=needs_weights, multiquery=True)
|
234 |
+
return (self.out_proj(context), attn_weights, past_key_value)
|
235 |
+
|
236 |
+
def attn_bias_shape(attn_impl, n_heads, seq_len, alibi, prefix_lm, causal, use_sequence_id):
|
237 |
if attn_impl == 'flash':
|
238 |
return None
|
239 |
elif attn_impl in ['torch', 'triton']:
|
245 |
return (1, 1, seq_len, seq_len)
|
246 |
return None
|
247 |
else:
|
248 |
+
raise ValueError(f'attn_impl={attn_impl!r} is an invalid setting.')
|
|
|
249 |
|
250 |
+
def build_attn_bias(attn_impl, attn_bias, n_heads, seq_len, causal=False, alibi=False, alibi_bias_max=8):
|
|
|
|
|
|
|
|
|
|
|
|
|
251 |
if attn_impl == 'flash':
|
252 |
return None
|
253 |
elif attn_impl in ['torch', 'triton']:
|
254 |
if alibi:
|
255 |
+
(device, dtype) = (attn_bias.device, attn_bias.dtype)
|
256 |
+
attn_bias = attn_bias.add(build_alibi_bias(n_heads, seq_len, full=not causal, alibi_bias_max=alibi_bias_max, device=device, dtype=dtype))
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
257 |
return attn_bias
|
258 |
else:
|
259 |
+
raise ValueError(f'attn_impl={attn_impl!r} is an invalid setting.')
|
260 |
+
|
261 |
+
def gen_slopes(n_heads, alibi_bias_max=8, device=None):
|
262 |
+
_n_heads = 2 ** math.ceil(math.log2(n_heads))
|
263 |
+
m = torch.arange(1, _n_heads + 1, dtype=torch.float32, device=device)
|
264 |
+
m = m.mul(alibi_bias_max / _n_heads)
|
265 |
+
slopes = 1.0 / torch.pow(2, m)
|
266 |
+
if _n_heads != n_heads:
|
267 |
+
slopes = torch.concat([slopes[1::2], slopes[::2]])[:n_heads]
|
268 |
+
return slopes.view(1, n_heads, 1, 1)
|
269 |
+
|
270 |
+
def build_alibi_bias(n_heads, seq_len, full=False, alibi_bias_max=8, device=None, dtype=None):
|
271 |
+
alibi_bias = torch.arange(1 - seq_len, 1, dtype=torch.int32, device=device).view(1, 1, 1, seq_len)
|
272 |
if full:
|
273 |
+
alibi_bias = alibi_bias - torch.arange(1 - seq_len, 1, dtype=torch.int32, device=device).view(1, 1, seq_len, 1)
|
|
|
|
|
|
|
274 |
alibi_bias = alibi_bias.abs().mul(-1)
|
275 |
+
slopes = gen_slopes(n_heads, alibi_bias_max, device=device)
|
276 |
+
alibi_bias = alibi_bias * slopes
|
277 |
+
return alibi_bias.to(dtype=dtype)
|
278 |
+
ATTN_CLASS_REGISTRY = {'multihead_attention': MultiheadAttention, 'multiquery_attention': MultiQueryAttention}
|
|
blocks.py
ADDED
@@ -0,0 +1,41 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
"""GPT Blocks used for the GPT Model."""
|
2 |
+
from typing import Dict, Optional, Tuple
|
3 |
+
import torch
|
4 |
+
import torch.nn as nn
|
5 |
+
from .attention import ATTN_CLASS_REGISTRY
|
6 |
+
from .norm import NORM_CLASS_REGISTRY
|
7 |
+
|
8 |
+
class MPTMLP(nn.Module):
|
9 |
+
|
10 |
+
def __init__(self, d_model: int, expansion_ratio: int, device: Optional[str]=None):
|
11 |
+
super().__init__()
|
12 |
+
self.up_proj = nn.Linear(d_model, expansion_ratio * d_model, device=device)
|
13 |
+
self.act = nn.GELU(approximate='none')
|
14 |
+
self.down_proj = nn.Linear(expansion_ratio * d_model, d_model, device=device)
|
15 |
+
self.down_proj._is_residual = True
|
16 |
+
|
17 |
+
def forward(self, x):
|
18 |
+
return self.down_proj(self.act(self.up_proj(x)))
|
19 |
+
|
20 |
+
class MPTBlock(nn.Module):
|
21 |
+
|
22 |
+
def __init__(self, d_model: int, n_heads: int, expansion_ratio: int, attn_config: Dict={'attn_type': 'multihead_attention', 'attn_pdrop': 0.0, 'attn_impl': 'triton', 'qk_ln': False, 'clip_qkv': None, 'softmax_scale': None, 'prefix_lm': False, 'attn_uses_sequence_id': False, 'alibi': False, 'alibi_bias_max': 8}, resid_pdrop: float=0.0, norm_type: str='low_precision_layernorm', verbose: int=0, device: Optional[str]=None, **kwargs):
|
23 |
+
del kwargs
|
24 |
+
super().__init__()
|
25 |
+
norm_class = NORM_CLASS_REGISTRY[norm_type.lower()]
|
26 |
+
attn_class = ATTN_CLASS_REGISTRY[attn_config['attn_type']]
|
27 |
+
self.norm_1 = norm_class(d_model, device=device)
|
28 |
+
self.attn = attn_class(attn_impl=attn_config['attn_impl'], clip_qkv=attn_config['clip_qkv'], qk_ln=attn_config['qk_ln'], softmax_scale=attn_config['softmax_scale'], attn_pdrop=attn_config['attn_pdrop'], d_model=d_model, n_heads=n_heads, verbose=verbose, device=device)
|
29 |
+
self.norm_2 = norm_class(d_model, device=device)
|
30 |
+
self.ffn = MPTMLP(d_model=d_model, expansion_ratio=expansion_ratio, device=device)
|
31 |
+
self.resid_attn_dropout = nn.Dropout(resid_pdrop)
|
32 |
+
self.resid_ffn_dropout = nn.Dropout(resid_pdrop)
|
33 |
+
|
34 |
+
def forward(self, x: torch.Tensor, past_key_value: Optional[Tuple[torch.Tensor]]=None, attn_bias: Optional[torch.Tensor]=None, attention_mask: Optional[torch.ByteTensor]=None, is_causal: bool=True) -> Tuple[torch.Tensor, Optional[Tuple[torch.Tensor]]]:
|
35 |
+
a = self.norm_1(x)
|
36 |
+
(b, _, past_key_value) = self.attn(a, past_key_value=past_key_value, attn_bias=attn_bias, attention_mask=attention_mask, is_causal=is_causal)
|
37 |
+
x = x + self.resid_attn_dropout(b)
|
38 |
+
m = self.norm_2(x)
|
39 |
+
n = self.ffn(m)
|
40 |
+
x = x + self.resid_ffn_dropout(n)
|
41 |
+
return (x, past_key_value)
|
config.json
CHANGED
@@ -1,45 +1,51 @@
|
|
1 |
{
|
2 |
-
"_name_or_path": "replit/replit-code-v1-3b",
|
3 |
-
"alibi": true,
|
4 |
-
"alibi_bias_max": 8,
|
5 |
"architectures": [
|
6 |
-
"
|
7 |
],
|
8 |
-
"
|
9 |
-
|
10 |
-
|
11 |
-
|
12 |
-
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
13 |
"auto_map": {
|
14 |
-
"AutoConfig": "
|
15 |
-
"AutoModelForCausalLM": "
|
16 |
},
|
17 |
"d_model": 2560,
|
18 |
-
"emb_init_std": null,
|
19 |
-
"emb_init_uniform_lim": null,
|
20 |
"emb_pdrop": 0,
|
21 |
"embedding_fraction": 1.0,
|
22 |
-
"
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
23 |
"init_device": "cpu",
|
24 |
-
"
|
25 |
-
"init_gain": 0,
|
26 |
-
"init_nonlinearity": "relu",
|
27 |
-
"init_std": 0.02,
|
28 |
"logit_scale": null,
|
29 |
-
"low_precision_layernorm": true,
|
30 |
"max_seq_len": 2048,
|
31 |
-
"
|
32 |
-
"model_type": "replit_lm",
|
33 |
"n_heads": 32,
|
34 |
"n_layers": 32,
|
35 |
"no_bias": true,
|
36 |
-
"
|
37 |
-
"prefix_lm": false,
|
38 |
"resid_pdrop": 0,
|
39 |
-
"softmax_scale": null,
|
40 |
"tokenizer_name": "replit/replit-code-v1-3b",
|
41 |
"torch_dtype": "float32",
|
42 |
-
"transformers_version": "4.
|
43 |
"use_cache": false,
|
44 |
"verbose": 0,
|
45 |
"vocab_size": 32768
|
1 |
{
|
|
|
|
|
|
|
2 |
"architectures": [
|
3 |
+
"MPTForCausalLM"
|
4 |
],
|
5 |
+
"attn_config": {
|
6 |
+
"alibi": true,
|
7 |
+
"alibi_bias_max": 8,
|
8 |
+
"attn_impl": "torch",
|
9 |
+
"attn_pdrop": 0,
|
10 |
+
"attn_type": "multihead_attention",
|
11 |
+
"attn_uses_sequence_id": false,
|
12 |
+
"clip_qkv": null,
|
13 |
+
"prefix_lm": false,
|
14 |
+
"qk_ln": false,
|
15 |
+
"softmax_scale": null
|
16 |
+
},
|
17 |
"auto_map": {
|
18 |
+
"AutoConfig": "configuration_mpt.MPTConfig",
|
19 |
+
"AutoModelForCausalLM": "modeling_mpt.MPTForCausalLM"
|
20 |
},
|
21 |
"d_model": 2560,
|
|
|
|
|
22 |
"emb_pdrop": 0,
|
23 |
"embedding_fraction": 1.0,
|
24 |
+
"expansion_ratio": 4,
|
25 |
+
"init_config": {
|
26 |
+
"emb_init_std": null,
|
27 |
+
"emb_init_uniform_lim": null,
|
28 |
+
"fan_mode": "fan_in",
|
29 |
+
"init_div_is_residual": true,
|
30 |
+
"init_gain": 0,
|
31 |
+
"init_nonlinearity": "relu",
|
32 |
+
"init_std": 0.02,
|
33 |
+
"name": "kaiming_normal_",
|
34 |
+
"verbose": 0
|
35 |
+
},
|
36 |
"init_device": "cpu",
|
37 |
+
"learned_pos_emb": true,
|
|
|
|
|
|
|
38 |
"logit_scale": null,
|
|
|
39 |
"max_seq_len": 2048,
|
40 |
+
"model_type": "mpt",
|
|
|
41 |
"n_heads": 32,
|
42 |
"n_layers": 32,
|
43 |
"no_bias": true,
|
44 |
+
"norm_type": "low_precision_layernorm",
|
|
|
45 |
"resid_pdrop": 0,
|
|
|
46 |
"tokenizer_name": "replit/replit-code-v1-3b",
|
47 |
"torch_dtype": "float32",
|
48 |
+
"transformers_version": "4.28.1",
|
49 |
"use_cache": false,
|
50 |
"verbose": 0,
|
51 |
"vocab_size": 32768
|
configuration_mpt.py
ADDED
@@ -0,0 +1,118 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
"""A HuggingFace-style model configuration."""
|
2 |
+
from typing import Dict, Optional, Union
|
3 |
+
from transformers import PretrainedConfig
|
4 |
+
attn_config_defaults: Dict = {'attn_type': 'multihead_attention', 'attn_pdrop': 0.0, 'attn_impl': 'triton', 'qk_ln': False, 'clip_qkv': None, 'softmax_scale': None, 'prefix_lm': False, 'attn_uses_sequence_id': False, 'alibi': False, 'alibi_bias_max': 8}
|
5 |
+
init_config_defaults: Dict = {'name': 'kaiming_normal_', 'fan_mode': 'fan_in', 'init_nonlinearity': 'relu', 'init_div_is_residual': True, 'emb_init_std': None, 'emb_init_uniform_lim': None, 'init_std': None, 'init_gain': 0.0}
|
6 |
+
|
7 |
+
class MPTConfig(PretrainedConfig):
|
8 |
+
model_type = 'mpt'
|
9 |
+
|
10 |
+
def __init__(self, d_model: int=2048, n_heads: int=16, n_layers: int=24, expansion_ratio: int=4, max_seq_len: int=2048, vocab_size: int=50368, resid_pdrop: float=0.0, emb_pdrop: float=0.0, learned_pos_emb: bool=True, attn_config: Dict=attn_config_defaults, init_device: str='cpu', logit_scale: Optional[Union[float, str]]=None, no_bias: bool=False, verbose: int=0, embedding_fraction: float=1.0, norm_type: str='low_precision_layernorm', use_cache: bool=False, init_config: Dict=init_config_defaults, **kwargs):
|
11 |
+
"""The MPT configuration class.
|
12 |
+
|
13 |
+
Args:
|
14 |
+
d_model (int): The size of the embedding dimension of the model.
|
15 |
+
n_heads (int): The number of attention heads.
|
16 |
+
n_layers (int): The number of layers in the model.
|
17 |
+
expansion_ratio (int): The ratio of the up/down scale in the MLP.
|
18 |
+
max_seq_len (int): The maximum sequence length of the model.
|
19 |
+
vocab_size (int): The size of the vocabulary.
|
20 |
+
resid_pdrop (float): The dropout probability applied to the attention output before combining with residual.
|
21 |
+
emb_pdrop (float): The dropout probability for the embedding layer.
|
22 |
+
learned_pos_emb (bool): Whether to use learned positional embeddings
|
23 |
+
attn_config (Dict): A dictionary used to configure the model's attention module:
|
24 |
+
attn_type (str): type of attention to use. Options: multihead_attention, multiquery_attention
|
25 |
+
attn_pdrop (float): The dropout probability for the attention layers.
|
26 |
+
attn_impl (str): The attention implementation to use. One of 'torch', 'flash', or 'triton'.
|
27 |
+
qk_ln (bool): Whether to apply layer normalization to the queries and keys in the attention layer.
|
28 |
+
clip_qkv (Optional[float]): If not None, clip the queries, keys, and values in the attention layer to
|
29 |
+
this value.
|
30 |
+
softmax_scale (Optional[float]): If not None, scale the softmax in the attention layer by this value. If None,
|
31 |
+
use the default scale of ``1/sqrt(d_keys)``.
|
32 |
+
prefix_lm (Optional[bool]): Whether the model should operate as a Prefix LM. This requires passing an
|
33 |
+
extra `prefix_mask` argument which indicates which tokens belong to the prefix. Tokens in the prefix
|
34 |
+
can attend to one another bi-directionally. Tokens outside the prefix use causal attention.
|
35 |
+
attn_uses_sequence_id (Optional[bool]): Whether to restrict attention to tokens that have the same sequence_id.
|
36 |
+
When the model is in `train` mode, this requires passing an extra `sequence_id` argument which indicates
|
37 |
+
which sub-sequence each token belongs to.
|
38 |
+
Defaults to ``False`` meaning any provided `sequence_id` will be ignored.
|
39 |
+
alibi (bool): Whether to use the alibi bias instead of position embeddings.
|
40 |
+
alibi_bias_max (int): The maximum value of the alibi bias.
|
41 |
+
init_device (str): The device to use for parameter initialization.
|
42 |
+
logit_scale (Optional[Union[float, str]]): If not None, scale the logits by this value.
|
43 |
+
no_bias (bool): Whether to use bias in all layers.
|
44 |
+
verbose (int): The verbosity level. 0 is silent.
|
45 |
+
embedding_fraction (float): The fraction to scale the gradients of the embedding layer by.
|
46 |
+
norm_type (str): choose type of norm to use
|
47 |
+
multiquery_attention (bool): Whether to use multiquery attention implementation.
|
48 |
+
use_cache (bool): Whether or not the model should return the last key/values attentions
|
49 |
+
init_config (Dict): A dictionary used to configure the model initialization:
|
50 |
+
init_config.name: The parameter initialization scheme to use. Options: 'default_', 'baseline_',
|
51 |
+
'kaiming_uniform_', 'kaiming_normal_', 'neox_init_', 'small_init_', 'xavier_uniform_', or
|
52 |
+
'xavier_normal_'. These mimic the parameter initialization methods in PyTorch.
|
53 |
+
init_div_is_residual (Union[int, float, str, bool]): Value to divide initial weights by if ``module._is_residual`` is True.
|
54 |
+
emb_init_std (Optional[float]): The standard deviation of the normal distribution used to initialize the embedding layer.
|
55 |
+
emb_init_uniform_lim (Optional[Union[Tuple[float, float], float]]): The lower and upper limits of the uniform distribution
|
56 |
+
used to initialize the embedding layer. Mutually exclusive with ``emb_init_std``.
|
57 |
+
init_std (float): The standard deviation of the normal distribution used to initialize the model,
|
58 |
+
if using the baseline_ parameter initialization scheme.
|
59 |
+
init_gain (float): The gain to use for parameter initialization with kaiming or xavier initialization schemes.
|
60 |
+
fan_mode (str): The fan mode to use for parameter initialization with kaiming initialization schemes.
|
61 |
+
init_nonlinearity (str): The nonlinearity to use for parameter initialization with kaiming initialization schemes.
|
62 |
+
---
|
63 |
+
See llmfoundry.models.utils.param_init_fns.py for info on other param init config options
|
64 |
+
"""
|
65 |
+
self.d_model = d_model
|
66 |
+
self.n_heads = n_heads
|
67 |
+
self.n_layers = n_layers
|
68 |
+
self.expansion_ratio = expansion_ratio
|
69 |
+
self.max_seq_len = max_seq_len
|
70 |
+
self.vocab_size = vocab_size
|
71 |
+
self.resid_pdrop = resid_pdrop
|
72 |
+
self.emb_pdrop = emb_pdrop
|
73 |
+
self.learned_pos_emb = learned_pos_emb
|
74 |
+
self.attn_config = attn_config
|
75 |
+
self.init_device = init_device
|
76 |
+
self.logit_scale = logit_scale
|
77 |
+
self.no_bias = no_bias
|
78 |
+
self.verbose = verbose
|
79 |
+
self.embedding_fraction = embedding_fraction
|
80 |
+
self.norm_type = norm_type
|
81 |
+
self.use_cache = use_cache
|
82 |
+
self.init_config = init_config
|
83 |
+
if 'name' in kwargs:
|
84 |
+
del kwargs['name']
|
85 |
+
if 'loss_fn' in kwargs:
|
86 |
+
del kwargs['loss_fn']
|
87 |
+
super().__init__(**kwargs)
|
88 |
+
self._validate_config()
|
89 |
+
|
90 |
+
def _set_config_defaults(self, config, config_defaults):
|
91 |
+
for (k, v) in config_defaults.items():
|
92 |
+
if k not in config:
|
93 |
+
config[k] = v
|
94 |
+
return config
|
95 |
+
|
96 |
+
def _validate_config(self):
|
97 |
+
self.attn_config = self._set_config_defaults(self.attn_config, attn_config_defaults)
|
98 |
+
self.init_config = self._set_config_defaults(self.init_config, init_config_defaults)
|
99 |
+
if self.d_model % self.n_heads != 0:
|
100 |
+
raise ValueError('d_model must be divisible by n_heads')
|
101 |
+
if any((prob < 0 or prob > 1 for prob in [self.attn_config['attn_pdrop'], self.resid_pdrop, self.emb_pdrop])):
|
102 |
+
raise ValueError("self.attn_config['attn_pdrop'], resid_pdrop, emb_pdrop are probabilities and must be between 0 and 1")
|
103 |
+
if self.attn_config['attn_impl'] not in ['torch', 'flash', 'triton']:
|
104 |
+
raise ValueError(f"Unknown attn_impl={self.attn_config['attn_impl']}")
|
105 |
+
if self.attn_config['prefix_lm'] and self.attn_config['attn_impl'] not in ['torch', 'triton']:
|
106 |
+
raise NotImplementedError('prefix_lm only implemented with torch and triton attention.')
|
107 |
+
if self.attn_config['alibi'] and self.attn_config['attn_impl'] not in ['torch', 'triton']:
|
108 |
+
raise NotImplementedError('alibi only implemented with torch and triton attention.')
|
109 |
+
if self.attn_config['attn_uses_sequence_id'] and self.attn_config['attn_impl'] not in ['torch', 'triton']:
|
110 |
+
raise NotImplementedError('attn_uses_sequence_id only implemented with torch and triton attention.')
|
111 |
+
if self.embedding_fraction > 1 or self.embedding_fraction <= 0:
|
112 |
+
raise ValueError('model.embedding_fraction must be between 0 (exclusive) and 1 (inclusive)!')
|
113 |
+
if isinstance(self.logit_scale, str) and self.logit_scale != 'inv_sqrt_d_model':
|
114 |
+
raise ValueError(f"self.logit_scale={self.logit_scale!r} is not recognized as an option; use numeric value or 'inv_sqrt_d_model'.")
|
115 |
+
if self.init_config.get('name', None) is None:
|
116 |
+
raise ValueError(f"self.init_config={self.init_config!r} 'name' needs to be set.")
|
117 |
+
if not self.learned_pos_emb and (not self.attn_config['alibi']):
|
118 |
+
raise ValueError(f'Positional information must be provided to the model using either learned_pos_emb or alibi.')
|
generation_config.json
CHANGED
@@ -1,5 +1,5 @@
|
|
1 |
{
|
2 |
"_from_model_config": true,
|
3 |
-
"transformers_version": "4.
|
4 |
"use_cache": false
|
5 |
}
|
1 |
{
|
2 |
"_from_model_config": true,
|
3 |
+
"transformers_version": "4.28.1",
|
4 |
"use_cache": false
|
5 |
}
|
hf_prefixlm_converter.py
ADDED
@@ -0,0 +1,415 @@
|
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|
|
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|
|
|
|
|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
|
|
|
|
|
|
|
|
|
|
|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
|
|
|
|
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|
|
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|
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|
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|
|
|
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|
|
|
|
|
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|
|
|
|
|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
"""Converts Huggingface Causal LM to Prefix LM.
|
2 |
+
|
3 |
+
Conversion does lightweight surgery on a HuggingFace
|
4 |
+
Causal LM to convert it to a Prefix LM.
|
5 |
+
|
6 |
+
Prefix LMs accepts a `bidirectional_mask` input in `forward`
|
7 |
+
and treat the input prompt as the prefix in `generate`.
|
8 |
+
"""
|
9 |
+
import math
|
10 |
+
import warnings
|
11 |
+
from types import MethodType
|
12 |
+
from typing import Any, Dict, List, Optional, Tuple, Union
|
13 |
+
import torch
|
14 |
+
from transformers.models.bloom.modeling_bloom import BaseModelOutputWithPastAndCrossAttentions, BloomForCausalLM, BloomModel, CausalLMOutputWithCrossAttentions, CrossEntropyLoss
|
15 |
+
from transformers.models.bloom.modeling_bloom import _expand_mask as _expand_mask_bloom
|
16 |
+
from transformers.models.bloom.modeling_bloom import _make_causal_mask as _make_causal_mask_bloom
|
17 |
+
from transformers.models.bloom.modeling_bloom import logging
|
18 |
+
from transformers.models.gpt2.modeling_gpt2 import GPT2LMHeadModel
|
19 |
+
from transformers.models.gpt_neo.modeling_gpt_neo import GPTNeoForCausalLM
|
20 |
+
from transformers.models.gpt_neox.modeling_gpt_neox import GPTNeoXForCausalLM
|
21 |
+
from transformers.models.gptj.modeling_gptj import GPTJForCausalLM
|
22 |
+
from transformers.models.opt.modeling_opt import OPTForCausalLM
|
23 |
+
from transformers.models.opt.modeling_opt import _expand_mask as _expand_mask_opt
|
24 |
+
from transformers.models.opt.modeling_opt import _make_causal_mask as _make_causal_mask_opt
|
25 |
+
logger = logging.get_logger(__name__)
|
26 |
+
_SUPPORTED_GPT_MODELS = (GPT2LMHeadModel, GPTJForCausalLM, GPTNeoForCausalLM, GPTNeoXForCausalLM)
|
27 |
+
CAUSAL_GPT_TYPES = Union[GPT2LMHeadModel, GPTJForCausalLM, GPTNeoForCausalLM, GPTNeoXForCausalLM]
|
28 |
+
|
29 |
+
def _convert_gpt_causal_lm_to_prefix_lm(model: CAUSAL_GPT_TYPES) -> CAUSAL_GPT_TYPES:
|
30 |
+
"""Converts a GPT-style Causal LM to a Prefix LM.
|
31 |
+
|
32 |
+
Supported HuggingFace model classes:
|
33 |
+
- `GPT2LMHeadModel`
|
34 |
+
- `GPTNeoForCausalLM`
|
35 |
+
- `GPTNeoXForCausalLM`
|
36 |
+
- `GPTJForCausalLM`
|
37 |
+
|
38 |
+
See `convert_hf_causal_lm_to_prefix_lm` for more details.
|
39 |
+
"""
|
40 |
+
if hasattr(model, '_prefix_lm_converted'):
|
41 |
+
return model
|
42 |
+
assert isinstance(model, _SUPPORTED_GPT_MODELS)
|
43 |
+
assert model.config.add_cross_attention == False, 'Only supports GPT-style decoder-only models'
|
44 |
+
|
45 |
+
def _get_attn_modules(model: CAUSAL_GPT_TYPES) -> List[torch.nn.Module]:
|
46 |
+
"""Helper that gets a list of the model's attention modules.
|
47 |
+
|
48 |
+
Each module has a `bias` buffer used for causal masking. The Prefix LM
|
49 |
+
conversion adds logic to dynamically manipulate these biases to support
|
50 |
+
Prefix LM attention masking.
|
51 |
+
"""
|
52 |
+
attn_modules = []
|
53 |
+
if isinstance(model, GPTNeoXForCausalLM):
|
54 |
+
blocks = model.gpt_neox.layers
|
55 |
+
else:
|
56 |
+
blocks = model.transformer.h
|
57 |
+
for block in blocks:
|
58 |
+
if isinstance(model, GPTNeoForCausalLM):
|
59 |
+
if block.attn.attention_type != 'global':
|
60 |
+
continue
|
61 |
+
attn_module = block.attn.attention
|
62 |
+
elif isinstance(model, GPTNeoXForCausalLM):
|
63 |
+
attn_module = block.attention
|
64 |
+
else:
|
65 |
+
attn_module = block.attn
|
66 |
+
attn_modules.append(attn_module)
|
67 |
+
return attn_modules
|
68 |
+
setattr(model, '_original_forward', getattr(model, 'forward'))
|
69 |
+
setattr(model, '_original_generate', getattr(model, 'generate'))
|
70 |
+
|
71 |
+
def forward(self: CAUSAL_GPT_TYPES, input_ids: Optional[torch.LongTensor]=None, past_key_values: Optional[Tuple[Tuple[torch.Tensor]]]=None, attention_mask: Optional[torch.FloatTensor]=None, bidirectional_mask: Optional[torch.Tensor]=None, token_type_ids: Optional[torch.LongTensor]=None, position_ids: Optional[torch.LongTensor]=None, head_mask: Optional[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):
|
72 |
+
"""Wraps original forward to enable PrefixLM attention."""
|
73 |
+
|
74 |
+
def call_og_forward():
|
75 |
+
if isinstance(self, GPTNeoXForCausalLM):
|
76 |
+
return self._original_forward(input_ids=input_ids, past_key_values=past_key_values, attention_mask=attention_mask, head_mask=head_mask, inputs_embeds=inputs_embeds, labels=labels, use_cache=use_cache, output_attentions=output_attentions, output_hidden_states=output_hidden_states, return_dict=return_dict)
|
77 |
+
else:
|
78 |
+
return self._original_forward(input_ids=input_ids, past_key_values=past_key_values, attention_mask=attention_mask, token_type_ids=token_type_ids, position_ids=position_ids, head_mask=head_mask, inputs_embeds=inputs_embeds, labels=labels, use_cache=use_cache, output_attentions=output_attentions, output_hidden_states=output_hidden_states, return_dict=return_dict)
|
79 |
+
if bidirectional_mask is None:
|
80 |
+
return call_og_forward()
|
81 |
+
assert isinstance(bidirectional_mask, torch.Tensor)
|
82 |
+
attn_modules = _get_attn_modules(model)
|
83 |
+
(b, s) = bidirectional_mask.shape
|
84 |
+
max_length = attn_modules[0].bias.shape[-1]
|
85 |
+
if s > max_length:
|
86 |
+
raise ValueError(f'bidirectional_mask sequence length (={s}) exceeds the ' + f'max length allowed by the model ({max_length}).')
|
87 |
+
assert s <= max_length
|
88 |
+
if s < max_length:
|
89 |
+
pad = torch.zeros((int(b), int(max_length - s)), dtype=bidirectional_mask.dtype, device=bidirectional_mask.device)
|
90 |
+
bidirectional_mask = torch.cat([bidirectional_mask, pad], dim=1)
|
91 |
+
bidirectional = bidirectional_mask.unsqueeze(1).unsqueeze(1)
|
92 |
+
for attn_module in attn_modules:
|
93 |
+
attn_module.bias.data = torch.logical_or(attn_module.bias.data, bidirectional)
|
94 |
+
output = call_og_forward()
|
95 |
+
for attn_module in attn_modules:
|
96 |
+
attn_module.bias.data = torch.tril(attn_module.bias.data[0, 0])[None, None]
|
97 |
+
return output
|
98 |
+
|
99 |
+
def generate(self: CAUSAL_GPT_TYPES, *args: tuple, **kwargs: Dict[str, Any]):
|
100 |
+
"""Wraps original generate to enable PrefixLM attention."""
|
101 |
+
attn_modules = _get_attn_modules(model)
|
102 |
+
for attn_module in attn_modules:
|
103 |
+
attn_module.bias.data[:] = 1
|
104 |
+
output = self._original_generate(*args, **kwargs)
|
105 |
+
for attn_module in attn_modules:
|
106 |
+
attn_module.bias.data = torch.tril(attn_module.bias.data[0, 0])[None, None]
|
107 |
+
return output
|
108 |
+
setattr(model, 'forward', MethodType(forward, model))
|
109 |
+
setattr(model, 'generate', MethodType(generate, model))
|
110 |
+
setattr(model, '_prefix_lm_converted', True)
|
111 |
+
return model
|
112 |
+
|
113 |
+
def _convert_bloom_causal_lm_to_prefix_lm(model: BloomForCausalLM) -> BloomForCausalLM:
|
114 |
+
"""Converts a BLOOM Causal LM to a Prefix LM.
|
115 |
+
|
116 |
+
Supported HuggingFace model classes:
|
117 |
+
- `BloomForCausalLM`
|
118 |
+
|
119 |
+
See `convert_hf_causal_lm_to_prefix_lm` for more details.
|
120 |
+
"""
|
121 |
+
if hasattr(model, '_prefix_lm_converted'):
|
122 |
+
return model
|
123 |
+
assert isinstance(model, BloomForCausalLM)
|
124 |
+
assert model.config.add_cross_attention == False, 'Only supports BLOOM decoder-only models'
|
125 |
+
|
126 |
+
def _prepare_attn_mask(self: BloomModel, attention_mask: torch.Tensor, bidirectional_mask: Optional[torch.Tensor], input_shape: Tuple[int, int], past_key_values_length: int) -> torch.BoolTensor:
|
127 |
+
combined_attention_mask = None
|
128 |
+
device = attention_mask.device
|
129 |
+
(_, src_length) = input_shape
|
130 |
+
if src_length > 1:
|
131 |
+
combined_attention_mask = _make_causal_mask_bloom(input_shape, device=device, past_key_values_length=past_key_values_length)
|
132 |
+
if bidirectional_mask is not None:
|
133 |
+
assert attention_mask.shape == bidirectional_mask.shape
|
134 |
+
expanded_bidirectional_mask = _expand_mask_bloom(bidirectional_mask, tgt_length=src_length)
|
135 |
+
combined_attention_mask = torch.logical_and(combined_attention_mask, expanded_bidirectional_mask)
|
136 |
+
expanded_attn_mask = _expand_mask_bloom(attention_mask, tgt_length=src_length)
|
137 |
+
combined_attention_mask = expanded_attn_mask if combined_attention_mask is None else expanded_attn_mask | combined_attention_mask
|
138 |
+
return combined_attention_mask
|
139 |
+
|
140 |
+
def _build_alibi_tensor(self: BloomModel, batch_size: int, query_length: int, key_length: int, dtype: torch.dtype, device: torch.device) -> torch.Tensor:
|
141 |
+
num_heads = self.config.n_head
|
142 |
+
closest_power_of_2 = 2 ** math.floor(math.log2(num_heads))
|
143 |
+
base = torch.tensor(2 ** (-2 ** (-(math.log2(closest_power_of_2) - 3))), device=device, dtype=torch.float32)
|
144 |
+
powers = torch.arange(1, 1 + closest_power_of_2, device=device, dtype=torch.int32)
|
145 |
+
slopes = torch.pow(base, powers)
|
146 |
+
if closest_power_of_2 != num_heads:
|
147 |
+
extra_base = torch.tensor(2 ** (-2 ** (-(math.log2(2 * closest_power_of_2) - 3))), device=device, dtype=torch.float32)
|
148 |
+
num_remaining_heads = min(closest_power_of_2, num_heads - closest_power_of_2)
|
149 |
+
extra_powers = torch.arange(1, 1 + 2 * num_remaining_heads, 2, device=device, dtype=torch.int32)
|
150 |
+
slopes = torch.cat([slopes, torch.pow(extra_base, extra_powers)], dim=0)
|
151 |
+
qa = torch.arange(query_length, device=device, dtype=torch.int32).view(-1, 1)
|
152 |
+
ka = torch.arange(key_length, device=device, dtype=torch.int32).view(1, -1)
|
153 |
+
diffs = qa - ka + key_length - query_length
|
154 |
+
diffs = -diffs.abs()
|
155 |
+
alibi = slopes.view(1, num_heads, 1, 1) * diffs.view(1, 1, query_length, key_length)
|
156 |
+
alibi = alibi.expand(batch_size, -1, -1, -1).reshape(-1, query_length, key_length)
|
157 |
+
return alibi.to(dtype)
|
158 |
+
KeyValueT = Tuple[torch.Tensor, torch.Tensor]
|
159 |
+
|
160 |
+
def forward(self: BloomModel, input_ids: Optional[torch.LongTensor]=None, past_key_values: Optional[Tuple[KeyValueT, ...]]=None, attention_mask: Optional[torch.Tensor]=None, bidirectional_mask: Optional[torch.Tensor]=None, head_mask: Optional[torch.LongTensor]=None, inputs_embeds: 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, **deprecated_arguments) -> Union[Tuple[torch.Tensor, ...], BaseModelOutputWithPastAndCrossAttentions]:
|
161 |
+
if deprecated_arguments.pop('position_ids', False) is not False:
|
162 |
+
warnings.warn('`position_ids` have no functionality in BLOOM and will be removed in v5.0.0. ' + 'You can safely ignore passing `position_ids`.', FutureWarning)
|
163 |
+
if len(deprecated_arguments) > 0:
|
164 |
+
raise ValueError(f'Got unexpected arguments: {deprecated_arguments}')
|
165 |
+
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
|
166 |
+
output_hidden_states = output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
|
167 |
+
use_cache = use_cache if use_cache is not None else self.config.use_cache
|
168 |
+
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
169 |
+
if input_ids is not None and inputs_embeds is not None:
|
170 |
+
raise ValueError('You cannot specify both input_ids and inputs_embeds at the same time')
|
171 |
+
elif input_ids is not None:
|
172 |
+
(batch_size, seq_length) = input_ids.shape
|
173 |
+
elif inputs_embeds is not None:
|
174 |
+
(batch_size, seq_length, _) = inputs_embeds.shape
|
175 |
+
else:
|
176 |
+
raise ValueError('You have to specify either input_ids or inputs_embeds')
|
177 |
+
if past_key_values is None:
|
178 |
+
past_key_values = tuple([None] * len(self.h))
|
179 |
+
head_mask = self.get_head_mask(head_mask, self.config.n_layer)
|
180 |
+
if inputs_embeds is None:
|
181 |
+
inputs_embeds = self.word_embeddings(input_ids)
|
182 |
+
hidden_states = self.word_embeddings_layernorm(inputs_embeds)
|
183 |
+
presents = () if use_cache else None
|
184 |
+
all_self_attentions = () if output_attentions else None
|
185 |
+
all_hidden_states = () if output_hidden_states else None
|
186 |
+
seq_length_with_past = seq_length
|
187 |
+
past_key_values_length = 0
|
188 |
+
if past_key_values[0] is not None:
|
189 |
+
tmp = past_key_values[0][0]
|
190 |
+
past_key_values_length = tmp.shape[2]
|
191 |
+
seq_length_with_past = seq_length_with_past + past_key_values_length
|
192 |
+
if attention_mask is None:
|
193 |
+
attention_mask = torch.ones((batch_size, seq_length_with_past), device=hidden_states.device)
|
194 |
+
else:
|
195 |
+
attention_mask = attention_mask.to(hidden_states.device)
|
196 |
+
alibi = self._build_alibi_tensor(batch_size=batch_size, query_length=seq_length, key_length=seq_length_with_past, dtype=hidden_states.dtype, device=hidden_states.device)
|
197 |
+
causal_mask = self._prepare_attn_mask(attention_mask, bidirectional_mask, input_shape=(batch_size, seq_length), past_key_values_length=past_key_values_length)
|
198 |
+
for (i, (block, layer_past)) in enumerate(zip(self.h, past_key_values)):
|
199 |
+
if output_hidden_states:
|
200 |
+
hst = (hidden_states,)
|
201 |
+
all_hidden_states = all_hidden_states + hst
|
202 |
+
if self.gradient_checkpointing and self.training:
|
203 |
+
if use_cache:
|
204 |
+
logger.warning('`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`...')
|
205 |
+
use_cache = False
|
206 |
+
|
207 |
+
def create_custom_forward(module):
|
208 |
+
|
209 |
+
def custom_forward(*inputs):
|
210 |
+
return module(*inputs, use_cache=use_cache, output_attentions=output_attentions)
|
211 |
+
return custom_forward
|
212 |
+
outputs = torch.utils.checkpoint.checkpoint(create_custom_forward(block), hidden_states, alibi, causal_mask, head_mask[i])
|
213 |
+
else:
|
214 |
+
outputs = block(hidden_states, layer_past=layer_past, attention_mask=causal_mask, head_mask=head_mask[i], use_cache=use_cache, output_attentions=output_attentions, alibi=alibi)
|
215 |
+
hidden_states = outputs[0]
|
216 |
+
if use_cache is True:
|
217 |
+
presents = presents + (outputs[1],)
|
218 |
+
if output_attentions:
|
219 |
+
oa = (outputs[2 if use_cache else 1],)
|
220 |
+
all_self_attentions = all_self_attentions + oa
|
221 |
+
hidden_states = self.ln_f(hidden_states)
|
222 |
+
if output_hidden_states:
|
223 |
+
hst = (hidden_states,)
|
224 |
+
all_hidden_states = all_hidden_states + hst
|
225 |
+
if not return_dict:
|
226 |
+
return tuple((v for v in [hidden_states, presents, all_hidden_states, all_self_attentions] if v is not None))
|
227 |
+
return BaseModelOutputWithPastAndCrossAttentions(last_hidden_state=hidden_states, past_key_values=presents, hidden_states=all_hidden_states, attentions=all_self_attentions)
|
228 |
+
setattr(model.transformer, '_prepare_attn_mask', MethodType(_prepare_attn_mask, model.transformer))
|
229 |
+
setattr(model.transformer, '_build_alibi_tensor', MethodType(_build_alibi_tensor, model.transformer))
|
230 |
+
setattr(model.transformer, 'forward', MethodType(forward, model.transformer))
|
231 |
+
KeyValueT = Tuple[torch.Tensor, torch.Tensor]
|
232 |
+
|
233 |
+
def forward(self: BloomForCausalLM, input_ids: Optional[torch.LongTensor]=None, past_key_values: Optional[Tuple[KeyValueT, ...]]=None, attention_mask: Optional[torch.Tensor]=None, bidirectional_mask: Optional[torch.Tensor]=None, head_mask: Optional[torch.Tensor]=None, inputs_embeds: Optional[torch.Tensor]=None, labels: Optional[torch.Tensor]=None, use_cache: Optional[bool]=None, output_attentions: Optional[bool]=None, output_hidden_states: Optional[bool]=None, return_dict: Optional[bool]=None, **deprecated_arguments) -> Union[Tuple[torch.Tensor], CausalLMOutputWithCrossAttentions]:
|
234 |
+
"""Replacement forward method for BloomCausalLM."""
|
235 |
+
if deprecated_arguments.pop('position_ids', False) is not False:
|
236 |
+
warnings.warn('`position_ids` have no functionality in BLOOM and will be removed ' + 'in v5.0.0. You can safely ignore passing `position_ids`.', FutureWarning)
|
237 |
+
if len(deprecated_arguments) > 0:
|
238 |
+
raise ValueError(f'Got unexpected arguments: {deprecated_arguments}')
|
239 |
+
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
240 |
+
transformer_outputs = self.transformer(input_ids, past_key_values=past_key_values, attention_mask=attention_mask, bidirectional_mask=bidirectional_mask, head_mask=head_mask, inputs_embeds=inputs_embeds, use_cache=use_cache, output_attentions=output_attentions, output_hidden_states=output_hidden_states, return_dict=return_dict)
|
241 |
+
hidden_states = transformer_outputs[0]
|
242 |
+
lm_logits = self.lm_head(hidden_states)
|
243 |
+
loss = None
|
244 |
+
if labels is not None:
|
245 |
+
shift_logits = lm_logits[..., :-1, :].contiguous()
|
246 |
+
shift_labels = labels[..., 1:].contiguous()
|
247 |
+
(batch_size, seq_length, vocab_size) = shift_logits.shape
|
248 |
+
loss_fct = CrossEntropyLoss()
|
249 |
+
loss = loss_fct(shift_logits.view(batch_size * seq_length, vocab_size), shift_labels.view(batch_size * seq_length))
|
250 |
+
if not return_dict:
|
251 |
+
output = (lm_logits,) + transformer_outputs[1:]
|
252 |
+
return (loss,) + output if loss is not None else output
|
253 |
+
return CausalLMOutputWithCrossAttentions(loss=loss, logits=lm_logits, past_key_values=transformer_outputs.past_key_values, hidden_states=transformer_outputs.hidden_states, attentions=transformer_outputs.attentions)
|
254 |
+
|
255 |
+
def prepare_inputs_for_generation(self: BloomForCausalLM, input_ids: torch.LongTensor, past: Optional[torch.Tensor]=None, attention_mask: Optional[torch.Tensor]=None, **kwargs) -> dict:
|
256 |
+
if past:
|
257 |
+
input_ids = input_ids[:, -1].unsqueeze(-1)
|
258 |
+
bidirectional_mask = None
|
259 |
+
if past[0][0].shape[0] == input_ids.shape[0]:
|
260 |
+
past = self._convert_to_bloom_cache(past)
|
261 |
+
else:
|
262 |
+
bidirectional_mask = torch.ones_like(input_ids)
|
263 |
+
return {'input_ids': input_ids, 'past_key_values': past, 'use_cache': True, 'attention_mask': attention_mask, 'bidirectional_mask': bidirectional_mask}
|
264 |
+
setattr(model, 'forward', MethodType(forward, model))
|
265 |
+
setattr(model, 'prepare_inputs_for_generation', MethodType(prepare_inputs_for_generation, model))
|
266 |
+
setattr(model, '_prefix_lm_converted', True)
|
267 |
+
return model
|
268 |
+
|
269 |
+
def _convert_opt_causal_lm_to_prefix_lm(model: OPTForCausalLM) -> OPTForCausalLM:
|
270 |
+
"""Converts an OPT Causal LM to a Prefix LM.
|
271 |
+
|
272 |
+
Supported HuggingFace model classes:
|
273 |
+
- `OPTForCausalLM`
|
274 |
+
|
275 |
+
See `convert_hf_causal_lm_to_prefix_lm` for more details.
|
276 |
+
"""
|
277 |
+
if hasattr(model, '_prefix_lm_converted'):
|
278 |
+
return model
|
279 |
+
assert isinstance(model, OPTForCausalLM)
|
280 |
+
assert model.config.add_cross_attention == False, 'Only supports OPT decoder-only models'
|
281 |
+
setattr(model, '_original_forward', getattr(model, 'forward'))
|
282 |
+
setattr(model, '_original_generate', getattr(model, 'generate'))
|
283 |
+
model.model.decoder.bidirectional_mask = None
|
284 |
+
|
285 |
+
def _prepare_decoder_attention_mask(self, attention_mask, input_shape, inputs_embeds, past_key_values_length):
|
286 |
+
combined_attention_mask = None
|
287 |
+
if input_shape[-1] > 1:
|
288 |
+
if self.bidirectional_mask == 'g':
|
289 |
+
(bsz, src_length) = input_shape
|
290 |
+
combined_attention_mask = torch.zeros((bsz, 1, src_length, src_length + past_key_values_length), dtype=inputs_embeds.dtype, device=inputs_embeds.device)
|
291 |
+
else:
|
292 |
+
combined_attention_mask = _make_causal_mask_opt(input_shape, inputs_embeds.dtype, past_key_values_length=past_key_values_length).to(inputs_embeds.device)
|
293 |
+
if self.bidirectional_mask is not None:
|
294 |
+
assert attention_mask.shape == self.bidirectional_mask.shape
|
295 |
+
expanded_bidirectional_mask = _expand_mask_opt(self.bidirectional_mask, inputs_embeds.dtype, tgt_len=input_shape[-1]).to(inputs_embeds.device)
|
296 |
+
combined_attention_mask = torch.maximum(expanded_bidirectional_mask, combined_attention_mask)
|
297 |
+
if attention_mask is not None:
|
298 |
+
expanded_attn_mask = _expand_mask_opt(attention_mask, inputs_embeds.dtype, tgt_len=input_shape[-1]).to(inputs_embeds.device)
|
299 |
+
combined_attention_mask = expanded_attn_mask if combined_attention_mask is None else expanded_attn_mask + combined_attention_mask
|
300 |
+
return combined_attention_mask
|
301 |
+
setattr(model.model.decoder, '_prepare_decoder_attention_mask', MethodType(_prepare_decoder_attention_mask, model.model.decoder))
|
302 |
+
|
303 |
+
def forward(self: OPTForCausalLM, input_ids: Optional[torch.LongTensor]=None, attention_mask: Optional[torch.Tensor]=None, bidirectional_mask: Optional[torch.ByteTensor]=None, head_mask: Optional[torch.Tensor]=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):
|
304 |
+
|
305 |
+
def call_og_forward():
|
306 |
+
return self._original_forward(input_ids=input_ids, attention_mask=attention_mask, head_mask=head_mask, past_key_values=past_key_values, inputs_embeds=inputs_embeds, labels=labels, use_cache=use_cache, output_attentions=output_attentions, output_hidden_states=output_hidden_states, return_dict=return_dict)
|
307 |
+
if bidirectional_mask is None:
|
308 |
+
return call_og_forward()
|
309 |
+
self.model.decoder.bidirectional_mask = bidirectional_mask
|
310 |
+
try:
|
311 |
+
outputs = call_og_forward()
|
312 |
+
except:
|
313 |
+
self.model.decoder.bidirectional_mask = None
|
314 |
+
raise
|
315 |
+
self.model.decoder.bidirectional_mask = None
|
316 |
+
return outputs
|
317 |
+
|
318 |
+
def generate(self: OPTForCausalLM, *args: tuple, **kwargs: Dict[str, Any]):
|
319 |
+
"""Wraps original generate to enable PrefixLM-style attention."""
|
320 |
+
self.model.decoder.bidirectional_mask = 'g'
|
321 |
+
try:
|
322 |
+
output = self._original_generate(*args, **kwargs)
|
323 |
+
except:
|
324 |
+
self.model.decoder.bidirectional_mask = None
|
325 |
+
raise
|
326 |
+
self.model.decoder.bidirectional_mask = None
|
327 |
+
return output
|
328 |
+
setattr(model, 'forward', MethodType(forward, model))
|
329 |
+
setattr(model, 'generate', MethodType(generate, model))
|
330 |
+
setattr(model, '_prefix_lm_converted', True)
|
331 |
+
return model
|
332 |
+
_SUPPORTED_HF_MODELS = _SUPPORTED_GPT_MODELS + (BloomForCausalLM, OPTForCausalLM)
|
333 |
+
CAUSAL_LM_TYPES = Union[GPT2LMHeadModel, GPTJForCausalLM, GPTNeoForCausalLM, GPTNeoXForCausalLM, BloomForCausalLM, OPTForCausalLM]
|
334 |
+
|
335 |
+
def convert_hf_causal_lm_to_prefix_lm(model: CAUSAL_LM_TYPES) -> CAUSAL_LM_TYPES:
|
336 |
+
"""Converts a HuggingFace Causal LM to a Prefix LM.
|
337 |
+
|
338 |
+
Supported HuggingFace model classes:
|
339 |
+
- `GPT2LMHeadModel`
|
340 |
+
- `GPTNeoForCausalLM`
|
341 |
+
- `GPTNeoXForCausalLM`
|
342 |
+
- `GPTJForCausalLM`
|
343 |
+
- `BloomForCausalLM`
|
344 |
+
- `OPTForCausalLM`
|
345 |
+
|
346 |
+
Conversion to a Prefix LM is done by modifying the `forward` method, and possibly also the
|
347 |
+
`generate` method and/or select underlying methods depending on the model class.
|
348 |
+
|
349 |
+
These changes preserve the model API, but add a new input to `forward`: "bidirectional_mask".
|
350 |
+
|
351 |
+
Notes on training:
|
352 |
+
To actually train the converted model as a Prefix LM, training batches will need to indicate
|
353 |
+
the prefix/target structure by including `bidirectional_mask` as part of the batch inputs.
|
354 |
+
|
355 |
+
**This is not a standard input and requires custom layers either within or after your dataloader.**
|
356 |
+
|
357 |
+
In addition to adding `bidirectional_mask` to the batch, this custom code should modify `labels`
|
358 |
+
such that `batch['labels'][batch['bidirectional_mask'] == 1] == -100`.
|
359 |
+
That is, the prefix portion of the sequence should not generate any loss. Loss should only be
|
360 |
+
generated by the target portion of the sequence.
|
361 |
+
|
362 |
+
Notes on `GPTNeoForCausalLM`:
|
363 |
+
To simplify the implementation, "global" and "local" attention layers are handled differently.
|
364 |
+
For "global" layers, we handle conversion as described above. For "local" layers, which use a
|
365 |
+
causal attention mask within a restricted local window, we do not alter the masking.
|
366 |
+
|
367 |
+
Notes on `forward` method conversion:
|
368 |
+
After conversion, the `forward` method will handle a new input, `bidirectional_mask`,
|
369 |
+
which should be a [batch_size, seq_length] byte tensor, where 1 indicates token positions
|
370 |
+
belonging to the prefix (prefix tokens can attend to one another bidirectionally), and
|
371 |
+
0 indicates token positions belonging to the target.
|
372 |
+
|
373 |
+
The new `forward` method will incorporate `bidirectional_mask` (if supplied) into the existing
|
374 |
+
causal mask, call the original `forward` method, and (if the causal mask is a buffer) reset
|
375 |
+
the causal masks before returning the result.
|
376 |
+
|
377 |
+
Notes on `generate` method conversion:
|
378 |
+
After conversion, the `generate` method will have the same signature but will internally
|
379 |
+
convert all causal masks to be purely bidirectional, call the original `generate` method, and
|
380 |
+
(where appropriate) reset the causal masks before returning the result.
|
381 |
+
|
382 |
+
This works thanks to the logic of the HuggingFace `generate` API, which first encodes the token
|
383 |
+
"prompt" passed to `generate` (which is treated as the prefix) and then sequentially generates
|
384 |
+
each new token. Encodings are cached as generation happens, so all prefix tokens can attend to one
|
385 |
+
another (as expected in a Prefix LM) and generated tokens can only attend to prefix tokens and
|
386 |
+
previously-generated tokens (also as expected in a Prefix LM).
|
387 |
+
|
388 |
+
To preserve the API, the original methods are renamed to `_original_forward` and
|
389 |
+
`_original_generate`, and replaced with new `forward` and `generate` methods that wrap
|
390 |
+
them, respectively. Although implementation details vary by model class.
|
391 |
+
"""
|
392 |
+
if isinstance(model, _SUPPORTED_GPT_MODELS):
|
393 |
+
return _convert_gpt_causal_lm_to_prefix_lm(model)
|
394 |
+
elif isinstance(model, BloomForCausalLM):
|
395 |
+
return _convert_bloom_causal_lm_to_prefix_lm(model)
|
396 |
+
elif isinstance(model, OPTForCausalLM):
|
397 |
+
return _convert_opt_causal_lm_to_prefix_lm(model)
|
398 |
+
else:
|
399 |
+
raise TypeError(f'Cannot convert model to Prefix LM. ' + f'Model does not belong to set of supported HF models:' + f'\n{_SUPPORTED_HF_MODELS}')
|
400 |
+
|
401 |
+
def add_bidirectional_mask_if_missing(batch: Dict[str, Any]):
|
402 |
+
"""Attempts to add bidirectional_mask to batch if missing.
|
403 |
+
|
404 |
+
Raises:
|
405 |
+
KeyError if bidirectional_mask is missing and can't be inferred
|
406 |
+
"""
|
407 |
+
if 'bidirectional_mask' not in batch:
|
408 |
+
if batch.get('mode', None) == 'icl_task':
|
409 |
+
batch['bidirectional_mask'] = batch['attention_mask'].clone()
|
410 |
+
for (i, continuation_indices) in enumerate(batch['continuation_indices']):
|
411 |
+
batch['bidirectional_mask'][i, continuation_indices] = 0
|
412 |
+
elif 'labels' in batch and 'attention_mask' in batch:
|
413 |
+
batch['bidirectional_mask'] = torch.logical_and(torch.eq(batch['attention_mask'], 1), torch.eq(batch['labels'], -100)).type_as(batch['attention_mask'])
|
414 |
+
else:
|
415 |
+
raise KeyError('No bidirectional_mask in batch and not sure how to construct one.')
|
meta_init_context.py
ADDED
@@ -0,0 +1,94 @@
|
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|
|
|
1 |
+
from contextlib import contextmanager
|
2 |
+
import torch
|
3 |
+
import torch.nn as nn
|
4 |
+
|
5 |
+
@contextmanager
|
6 |
+
def init_empty_weights(include_buffers: bool=False):
|
7 |
+
"""Meta initialization context manager.
|
8 |
+
|
9 |
+
A context manager under which models are initialized with all parameters
|
10 |
+
on the meta device, therefore creating an empty model. Useful when just
|
11 |
+
initializing the model would blow the available RAM.
|
12 |
+
|
13 |
+
Args:
|
14 |
+
include_buffers (`bool`, *optional*, defaults to `False`): Whether or
|
15 |
+
not to also put all buffers on the meta device while initializing.
|
16 |
+
|
17 |
+
Example:
|
18 |
+
```python
|
19 |
+
import torch.nn as nn
|
20 |
+
|
21 |
+
# Initialize a model with 100 billions parameters in no time and without using any RAM.
|
22 |
+
with init_empty_weights():
|
23 |
+
tst = nn.Sequential(*[nn.Linear(10000, 10000) for _ in range(1000)])
|
24 |
+
```
|
25 |
+
|
26 |
+
<Tip warning={true}>
|
27 |
+
|
28 |
+
Any model created under this context manager has no weights. As such you can't do something like
|
29 |
+
`model.to(some_device)` with it. To load weights inside your empty model, see [`load_checkpoint_and_dispatch`].
|
30 |
+
|
31 |
+
</Tip>
|
32 |
+
"""
|
33 |
+
with init_on_device(torch.device('meta'), include_buffers=include_buffers) as f:
|
34 |
+
yield f
|
35 |
+
|
36 |
+
@contextmanager
|
37 |
+
def init_on_device(device: torch.device, include_buffers: bool=False):
|
38 |
+
"""Device initialization context manager.
|
39 |
+
|
40 |
+
A context manager under which models are initialized with all parameters
|
41 |
+
on the specified device.
|
42 |
+
|
43 |
+
Args:
|
44 |
+
device (`torch.device`): Device to initialize all parameters on.
|
45 |
+
include_buffers (`bool`, *optional*, defaults to `False`): Whether or
|
46 |
+
not to also put all buffers on the meta device while initializing.
|
47 |
+
|
48 |
+
Example:
|
49 |
+
```python
|
50 |
+
import torch.nn as nn
|
51 |
+
|
52 |
+
with init_on_device(device=torch.device("cuda")):
|
53 |
+
tst = nn.Liner(100, 100) # on `cuda` device
|
54 |
+
```
|
55 |
+
"""
|
56 |
+
old_register_parameter = nn.Module.register_parameter
|
57 |
+
if include_buffers:
|
58 |
+
old_register_buffer = nn.Module.register_buffer
|
59 |
+
|
60 |
+
def register_empty_parameter(module, name, param):
|
61 |
+
old_register_parameter(module, name, param)
|
62 |
+
if param is not None:
|
63 |
+
param_cls = type(module._parameters[name])
|
64 |
+
kwargs = module._parameters[name].__dict__
|
65 |
+
module._parameters[name] = param_cls(module._parameters[name].to(device), **kwargs)
|
66 |
+
|
67 |
+
def register_empty_buffer(module, name, buffer):
|
68 |
+
old_register_buffer(module, name, buffer)
|
69 |
+
if buffer is not None:
|
70 |
+
module._buffers[name] = module._buffers[name].to(device)
|
71 |
+
if include_buffers:
|
72 |
+
tensor_constructors_to_patch = {torch_function_name: getattr(torch, torch_function_name) for torch_function_name in ['empty', 'zeros', 'ones', 'full']}
|
73 |
+
else:
|
74 |
+
tensor_constructors_to_patch = {}
|
75 |
+
|
76 |
+
def patch_tensor_constructor(fn):
|
77 |
+
|
78 |
+
def wrapper(*args, **kwargs):
|
79 |
+
kwargs['device'] = device
|
80 |
+
return fn(*args, **kwargs)
|
81 |
+
return wrapper
|
82 |
+
try:
|
83 |
+
nn.Module.register_parameter = register_empty_parameter
|
84 |
+
if include_buffers:
|
85 |
+
nn.Module.register_buffer = register_empty_buffer
|
86 |
+
for torch_function_name in tensor_constructors_to_patch.keys():
|
87 |
+
setattr(torch, torch_function_name, patch_tensor_constructor(getattr(torch, torch_function_name)))
|
88 |
+
yield
|
89 |
+
finally:
|
90 |
+
nn.Module.register_parameter = old_register_parameter
|
91 |
+
if include_buffers:
|
92 |
+
nn.Module.register_buffer = old_register_buffer
|
93 |
+
for (torch_function_name, old_torch_function) in tensor_constructors_to_patch.items():
|
94 |
+
setattr(torch, torch_function_name, old_torch_function)
|
modeling_mpt.py
ADDED
@@ -0,0 +1,291 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|