Implement huggingface checkpoint loading

Author: lshpku

examples/pre-training/ernie/pretrain.py

@@ -63,6 +63,8 @@
 
 from config import get_config
 
+from safetensors import safe_open
+
 try:
     from paddleformers.trainer.trainer_utils import log_trainer_start
 except ImportError:
@@ -164,6 +166,118 @@ def _collate_data(data, stack_fn=Stack()):
     return train_dataset, valid_dataset, test_dataset, _collate_data
 
 
+def load_huggingface_checkpoint(model, args):
+    fused_rms_norm_replace = [
+        ("self_attn.fused_rms_norm_linear.rms_norm_weight", "input_layernorm.weight"),
+        ("self_attn.fused_rms_norm_linear.linear_weight", "self_attn.qkv_proj.weight"),
+    ]
+    shared_layers_prefix = "shared_layers.embed_weight_share."
+    unnamed_layers = ["ernie.norm.weight", "lm_head.weight"]
+
+    logger.info(f"Loading huggingface checkpoint from {args.model_name_or_path}")
+    with open(
+        os.path.join(args.model_name_or_path, "model.safetensors.index.json")
+    ) as f:
+        weight_map = json.load(f)["weight_map"]
+
+    ep_degree = fleet.get_hybrid_communicate_group().get_expert_parallel_world_size()
+    ep_rank = fleet.get_hybrid_communicate_group().get_expert_parallel_rank()
+    expert_offset = (model.config.moe_num_experts // ep_degree) * ep_rank
+
+    def param_to_weight(name):
+        # for PP=1, we only need to substitute the fused_rms_norm and expert_id
+        for src, dst in fused_rms_norm_replace:
+            name = name.replace(src, dst)
+        if m := re.search(r"mlp\.experts\.(\d+)", name):
+            expert_id = expert_offset + int(m.group(1))
+            s, e = m.span()
+            name = name[:s] + f"mlp.experts.{expert_id}" + name[e:]
+        if isinstance(model, ErnieMoEForCausalLM):
+            return name
+
+        # for PP>1, we also need to handle special layers and adjust layer_idx
+        if name.startswith(shared_layers_prefix):
+            return "ernie." + name[len(shared_layers_prefix) :]
+        layer_idx, stem = name.split(".", maxsplit=1)
+        if stem == "weight":
+            return unnamed_layers.pop(0)
+        if stem.startswith("mtp"):
+            return f"ernie.{stem}"
+        return f"ernie.layers.{int(layer_idx) - 1}.{stem}"
+
+    def try_torch_format(weight_key):
+        if weight_key.startswith("ernie."):
+            weight_key = "model." + weight_key[6:]
+
+        key_decompose = [weight_key]
+        if ".up_gate_proj." in weight_key:
+            key_decompose = [
+                weight_key.replace(".up_gate_proj.", ".gate_proj."),
+                weight_key.replace(".up_gate_proj.", ".up_proj."),
+            ]
+        elif ".qkv_proj." in weight_key:
+            key_decompose = [
+                weight_key.replace(".qkv_proj.", ".q_proj."),
+                weight_key.replace(".qkv_proj.", ".k_proj."),
+                weight_key.replace(".qkv_proj.", ".v_proj."),
+            ]
+
+        tensor_decompose = []
+        for key in key_decompose:
+            if not (weight_file := weight_map.get(key)):
+                return None
+            with safe_open(
+                os.path.join(args.model_name_or_path, weight_file),
+                framework="paddle",
+                device="cpu",
+            ) as f:
+                tensor = f.get_tensor(key)
+            if "_proj." in key or ".gate." in key:
+                tensor = tensor.T.contiguous()
+            tensor_decompose.append(tensor)
+
+        if len(tensor_decompose) == 1:
+            return tensor_decompose[0]
+        else:
+            return paddle.concat(tensor_decompose, axis=-1)
+
+    def auto_fix_shape(param, weight):
+        assert len(param.shape) == len(weight.shape), "rank not match"
+        if (
+            len(param.shape) == 2
+            and param.shape[0] == weight.shape[1]
+            and param.shape[1] == weight.shape[0]
+        ):
+            return weight.T.contiguous()
+        assert all(
+            p_dim <= w_dim for p_dim, w_dim in zip(param.shape, weight.shape)
+        ), "weight too small"
+        indices = tuple(slice(0, dim) for dim in param.shape)
+        return weight[indices].contiguous()
+
+    for name, param in model.named_parameters():
+        weight_key = param_to_weight(name)
+        if weight_file := weight_map.get(weight_key):
+            with safe_open(
+                os.path.join(args.model_name_or_path, weight_file),
+                framework="paddle",
+            ) as f:
+                weight = f.get_tensor(weight_key)
+        elif (weight := try_torch_format(weight_key)) is None:
+            logger.warning(
+                f"param `{name}`'s weight `{weight_key}` not found. "
+                "Skip initializing."
+            )
+            continue
+        if param.shape != weight.shape:
+            logger.warning(
+                f"param `{name}`'s shape doesn't match weight `{weight_key}`: "
+                f"{param.shape} and {weight.shape}. Auto fixing."
+            )
+            weight = auto_fix_shape(param, weight)
+        param.copy_(weight)
+
+
 def main():
     if set_affinity is not None:
         set_affinity_code = set_affinity()
@@ -482,21 +596,12 @@ def sname_to_tname(pp_model):
         cfg.enable_delay_scale_loss = args.enable_delay_scale_loss
         register_pp_reshard_information(cfg.num_hidden_layers)
 
-        if args.from_scratch:
-            model = ErnieMoEForCausalLMPipe(cfg)
-        else:
-            model = ErnieMoEForCausalLMPipe.from_pretrained(
-                args.model_name_or_path,
-                config=cfg,
-            )
+        model = ErnieMoEForCausalLMPipe(cfg)
     else:
-        if args.from_scratch:
-            model = ErnieMoEForCausalLM(cfg)
-        else:
-            model = ErnieMoEForCausalLM.from_pretrained(
-                args.model_name_or_path,
-                config=cfg,
-            )
+        model = ErnieMoEForCausalLM(cfg)
+
+    if not args.from_scratch:
+        load_huggingface_checkpoint(model, args)
 
     cfg = model.config
     logger.info(f"using model type:{type(model)}")