use the same model structure and module names as HF

This commit is contained in:
Awni Hannun
2024-01-03 08:26:46 -08:00
parent 3fefd2e8eb
commit 2e2acc4349
2 changed files with 78 additions and 108 deletions

View File

@@ -17,70 +17,18 @@ from models import Model, ModelArgs
from mlx.utils import tree_flatten, tree_map, tree_unflatten
def convert(hf_path: str, dtype: str):
# Download model, config and tokenizer from HF
def fetch_from_hub(hf_path: str, dtype: str):
model = transformers.AutoModelForCausalLM.from_pretrained(
hf_path,
trust_remote_code=True,
torch_dtype=getattr(torch, dtype),
).state_dict()
config = transformers.AutoConfig.from_pretrained(hf_path)
tokenizer = transformers.AutoTokenizer.from_pretrained(
hf_path,
trust_remote_code=True,
)
# things to change
# 1. there's no "model." in the weight names
model = {k.replace("model.", ""): v for k, v in model.items()}
# 2. mlp is called feed_forward
model = {k.replace("mlp", "feed_forward"): v for k, v in model.items()}
# 3. up_proj, down_proj, gate_proj
model = {k.replace("down_proj", "w2"): v for k, v in model.items()}
model = {k.replace("up_proj", "w3"): v for k, v in model.items()}
model = {k.replace("gate_proj", "w1"): v for k, v in model.items()}
# 4. layernorms
model = {
k.replace("input_layernorm", "attention_norm"): v for k, v in model.items()
}
model = {
k.replace("post_attention_layernorm", "ffn_norm"): v for k, v in model.items()
}
# 5. lm head
model = {k.replace("lm_head", "output"): v for k, v in model.items()}
# 6. token emb
model = {k.replace("embed_tokens", "tok_embeddings"): v for k, v in model.items()}
# 7. attention
model = {k.replace("self_attn", "attention"): v for k, v in model.items()}
model = {k.replace("q_proj", "wq"): v for k, v in model.items()}
model = {k.replace("k_proj", "wk"): v for k, v in model.items()}
model = {k.replace("v_proj", "wv"): v for k, v in model.items()}
model = {k.replace("o_proj", "wo"): v for k, v in model.items()}
params = {}
params["model_type"] = "llama"
params["dim"] = config.hidden_size
params["hidden_dim"] = config.intermediate_size
params["head_dim"] = config.hidden_size // config.num_attention_heads
params["n_heads"] = config.num_attention_heads
if hasattr(config, "num_key_value_heads"):
params["n_kv_heads"] = config.num_key_value_heads
params["n_layers"] = config.num_hidden_layers
params["vocab_size"] = config.vocab_size
params["norm_eps"] = config.rms_norm_eps
params["rope_traditional"] = False
params["rope_theta"] = getattr(config, "rope_theta", 10000)
for k, v in model.items():
model[k] = mx.array(v.numpy())
return model, params, tokenizer
return model, config.to_dict(), tokenizer
def quantize(weights, config, args):
@@ -89,8 +37,7 @@ def quantize(weights, config, args):
# Load the model:
model = Model(ModelArgs(**config))
weights = tree_map(mx.array, weights)
# TODO replace with model.load_weights
model.update(tree_unflatten(list(weights.items())))
model.load_weights(list(weights.items()))
# Quantize the model:
nn.QuantizedLinear.quantize_module(model, args.q_group_size, args.q_bits)
@@ -163,7 +110,7 @@ if __name__ == "__main__":
args = parser.parse_args()
print("[INFO] Loading")
weights, config, tokenizer = convert(args.hf_path, args.dtype)
weights, config, tokenizer = fetch_from_hub(args.hf_path, args.dtype)
if args.quantize:
print("[INFO] Quantizing")
weights, config = quantize(weights, config, args)

View File

@@ -2,6 +2,7 @@
from dataclasses import dataclass
import glob
import inspect
import json
from pathlib import Path
from typing import Optional, Tuple
@@ -15,17 +16,27 @@ from huggingface_hub import snapshot_download
@dataclass
class ModelArgs:
dim: int
n_layers: int
head_dim: int
hidden_dim: int
n_heads: int
n_kv_heads: int
norm_eps: float
hidden_size: int
num_hidden_layers: int
intermediate_size: int
num_attention_heads: int
rms_norm_eps: float
vocab_size: int
num_key_value_heads: int = None
rope_theta: float = 10000
rope_traditional: bool = True
rope_traditional: bool = False
model_type: str = None
def __post_init__(self):
if self.num_key_value_heads is None:
self.num_key_value_heads = self.num_attention_heads
@classmethod
def from_dict(cls, params):
return cls(**{
k: v for k, v in params.items()
if k in inspect.signature(cls).parameters
})
class RMSNorm(nn.Module):
def __init__(self, dims: int, eps: float = 1e-5):
@@ -44,20 +55,22 @@ class RMSNorm(nn.Module):
class Attention(nn.Module):
def __init__(self, args: ModelArgs):
super().__init__()
self.args = args
self.n_heads: int = args.n_heads
self.n_kv_heads: int = args.n_kv_heads
self.repeats = self.n_heads // self.n_kv_heads
dim = args.hidden_size
self.n_heads = n_heads = args.num_attention_heads
self.n_kv_heads = n_kv_heads = args.num_key_value_heads
self.scale = self.args.head_dim**-0.5
self.repeats = n_heads // n_kv_heads
self.wq = nn.Linear(args.dim, args.n_heads * args.head_dim, bias=False)
self.wk = nn.Linear(args.dim, args.n_kv_heads * args.head_dim, bias=False)
self.wv = nn.Linear(args.dim, args.n_kv_heads * args.head_dim, bias=False)
self.wo = nn.Linear(args.n_heads * args.head_dim, args.dim, bias=False)
self.rope = nn.RoPE(args.head_dim, traditional=args.rope_traditional, base=args.rope_theta)
head_dim = args.hidden_size // n_heads
self.scale = head_dim**-0.5
self.q_proj = nn.Linear(dim, n_heads * head_dim, bias=False)
self.k_proj = nn.Linear(dim, n_kv_heads * head_dim, bias=False)
self.v_proj = nn.Linear(dim, n_kv_heads * head_dim, bias=False)
self.o_proj = nn.Linear(n_heads * head_dim, dim, bias=False)
self.rope = nn.RoPE(head_dim, traditional=args.rope_traditional, base=args.rope_theta)
def __call__(
self,
@@ -67,7 +80,7 @@ class Attention(nn.Module):
) -> mx.array:
B, L, D = x.shape
queries, keys, values = self.wq(x), self.wk(x), self.wv(x)
queries, keys, values = self.q_proj(x), self.k_proj(x), self.v_proj(x)
# Prepare the queries, keys and values for the attention computation
queries = queries.reshape(B, L, self.n_heads, -1).transpose(0, 2, 1, 3)
@@ -78,7 +91,8 @@ class Attention(nn.Module):
a = mx.concatenate([mx.expand_dims(a, 2)] * self.repeats, axis=2)
return a.reshape([B, self.n_heads, L, -1])
keys, values = map(repeat, (keys, values))
if self.repeats > 1:
keys, values = map(repeat, (keys, values))
if cache is not None:
key_cache, value_cache = cache
@@ -95,30 +109,29 @@ class Attention(nn.Module):
scores += mask
scores = mx.softmax(scores.astype(mx.float32), axis=-1).astype(scores.dtype)
output = (scores @ values).transpose(0, 2, 1, 3).reshape(B, L, -1)
return self.wo(output), (keys, values)
return self.o_proj(output), (keys, values)
class FeedForward(nn.Module):
def __init__(self, args: ModelArgs):
class MLP(nn.Module):
def __init__(self, dim, hidden_dim):
super().__init__()
self.w1 = nn.Linear(args.dim, args.hidden_dim, bias=False)
self.w2 = nn.Linear(args.hidden_dim, args.dim, bias=False)
self.w3 = nn.Linear(args.dim, args.hidden_dim, bias=False)
self.gate_proj = nn.Linear(dim, hidden_dim, bias=False)
self.down_proj = nn.Linear(hidden_dim, dim, bias=False)
self.up_proj = nn.Linear(dim, hidden_dim, bias=False)
def __call__(self, x) -> mx.array:
return self.w2(nn.silu(self.w1(x)) * self.w3(x))
return self.down_proj(nn.silu(self.gate_proj(x)) * self.up_proj(x))
class TransformerBlock(nn.Module):
def __init__(self, args: ModelArgs):
super().__init__()
self.n_heads = args.n_heads
self.dim = args.dim
self.attention = Attention(args)
self.feed_forward = FeedForward(args=args)
self.attention_norm = RMSNorm(args.dim, eps=args.norm_eps)
self.ffn_norm = RMSNorm(args.dim, eps=args.norm_eps)
self.num_attention_heads = args.num_attention_heads
self.hidden_size = args.hidden_size
self.self_attn = Attention(args)
self.mlp = MLP(args.hidden_size, args.intermediate_size)
self.input_layernorm = RMSNorm(args.hidden_size, eps=args.rms_norm_eps)
self.post_attention_layernorm = RMSNorm(args.hidden_size, eps=args.rms_norm_eps)
self.args = args
def __call__(
@@ -127,31 +140,30 @@ class TransformerBlock(nn.Module):
mask: Optional[mx.array] = None,
cache: Optional[Tuple[mx.array, mx.array]] = None,
) -> mx.array:
r, cache = self.attention(self.attention_norm(x), mask, cache)
r, cache = self.self_attn(self.input_layernorm(x), mask, cache)
h = x + r
r = self.feed_forward(self.ffn_norm(h))
r = self.mlp(self.post_attention_layernorm(h))
out = h + r
return out, cache
class Model(nn.Module):
class LlamaModel(nn.Module):
def __init__(self, args: ModelArgs):
super().__init__()
self.args = args
self.vocab_size = args.vocab_size
self.n_layers = args.n_layers
self.num_hidden_layers = args.num_hidden_layers
assert self.vocab_size > 0
self.tok_embeddings = nn.Embedding(args.vocab_size, args.dim)
self.layers = [TransformerBlock(args=args) for _ in range(args.n_layers)]
self.norm = RMSNorm(args.dim, eps=args.norm_eps)
self.output = nn.Linear(args.dim, args.vocab_size, bias=False)
self.embed_tokens = nn.Embedding(args.vocab_size, args.hidden_size)
self.layers = [TransformerBlock(args=args) for _ in range(args.num_hidden_layers)]
self.norm = RMSNorm(args.hidden_size, eps=args.rms_norm_eps)
def __call__(
self,
inputs: mx.array,
cache=None,
):
h = self.tok_embeddings(inputs)
h = self.embed_tokens(inputs)
mask = None
if h.shape[1] > 1:
@@ -164,7 +176,22 @@ class Model(nn.Module):
for e, layer in enumerate(self.layers):
h, cache[e] = layer(h, mask, cache[e])
return self.output(self.norm(h)), cache
return self.norm(h), cache
class Model(nn.Module):
def __init__(self, args: ModelArgs):
super().__init__()
self.model = LlamaModel(args)
self.lm_head = nn.Linear(args.hidden_size, args.vocab_size, bias=False)
def __call__(
self,
inputs: mx.array,
cache=None,
):
out, cache = self.model(inputs, cache)
return self.lm_head(out), cache
def load(path_or_hf_repo: str):
@@ -178,9 +205,8 @@ def load(path_or_hf_repo: str):
with open(model_path / "config.json", "r") as f:
config = json.loads(f.read())
config.pop("model_type", None)
quantization = config.pop("quantization", None)
model_args = ModelArgs(**config)
quantization = config.get("quantization", None)
model_args = ModelArgs.from_dict(config)
weight_files = glob.glob(str(model_path / "weights.*.safetensors"))
if len(weight_files) == 0:
@@ -194,14 +220,11 @@ def load(path_or_hf_repo: str):
if quantization is not None:
nn.QuantizedLinear.quantize_module(model, **quantization)
# TODO replace with
# model.load_weights(weights)
model.update(tree_unflatten(list(weights.items())))
model.load_weights(list(weights.items()))
mx.eval(model.parameters())
tokenizer = AutoTokenizer.from_pretrained(
model_path,
trust_remote_code=True,
)
return model, tokenizer