Merge 138c367ddb into 21ec325dba

[fix] 用 AST 求值器替换工具里的 eval()，并修复 Windows 上工具调用全部静默失败

scripts/eval_toolcall.py

@@ -12,7 +12,7 @@ from datetime import datetime
 from transformers import AutoTokenizer, AutoModelForCausalLM, TextStreamer
 from openai import OpenAI
 from model.model_minimind import MiniMindConfig, MiniMindForCausalLM
-from trainer.trainer_utils import setup_seed, get_model_params
+from trainer.trainer_utils import setup_seed, get_model_params, safe_math_eval
 warnings.filterwarnings('ignore')
 
 TOOLS = [
@@ -27,7 +27,7 @@ TOOLS = [
 ]
 
 MOCK_RESULTS = {
-    "calculate_math": lambda args: {"result": str(eval(str(args.get("expression", "0")).replace("^", "**").replace("×", "*").replace("÷", "/").replace("−", "-").replace("²", "**2").replace("³", "**3").replace("（", "(").replace("）", ")")))},
+    "calculate_math": lambda args: {"result": str(safe_math_eval(args.get("expression", "0")))},
     "get_current_time": lambda args: {"datetime": datetime.now().strftime("%Y-%m-%d %H:%M:%S"), "timezone": args.get("timezone", "Asia/Shanghai")},
     "random_number": lambda args: {"result": random.randint(int(args.get("min", 0)), int(args.get("max", 100)))},
     "text_length": lambda args: {"characters": len(args.get("text", "")), "words": len(args.get("text", "").split())},

scripts/web_demo.py

@@ -2,6 +2,7 @@ import random
 import re
 import json
 import os
+import sys
 from threading import Thread
 
 import torch
@@ -9,6 +10,9 @@ import numpy as np
 import streamlit as st
 from transformers import AutoModelForCausalLM, AutoTokenizer, TextIteratorStreamer
 
+sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
+from trainer.trainer_utils import safe_math_eval
+
 st.set_page_config(page_title="MiniMind", initial_sidebar_state="collapsed")
 
 st.markdown("""
@@ -125,7 +129,7 @@ def execute_tool(tool_name, args):
     import datetime
     try:
         if tool_name == 'calculate_math':
-            return {"result": eval(args.get('expression', '0'))}
+            return {"result": safe_math_eval(args.get('expression', '0'))}
         elif tool_name == 'get_current_time':
             tz = args.get('timezone', 'Asia/Shanghai')
             return {"result": datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')}

trainer/train_agent.py

@@ -10,7 +10,6 @@ import gc
 import json
 import math
 import random
-import signal
 import argparse
 import warnings
 import torch
@@ -24,7 +23,7 @@ from torch.optim.lr_scheduler import CosineAnnealingLR
 from transformers import AutoTokenizer
 from model.model_minimind import MiniMindConfig, MiniMindForCausalLM
 from dataset.lm_dataset import AgentRLDataset
-from trainer.trainer_utils import Logger, is_main_process, lm_checkpoint, init_distributed_mode, setup_seed, SkipBatchSampler, init_model, LMForRewardModel
+from trainer.trainer_utils import Logger, is_main_process, lm_checkpoint, init_distributed_mode, setup_seed, SkipBatchSampler, init_model, LMForRewardModel, safe_math_eval
 from trainer.rollout_engine import create_rollout_engine, compute_per_token_logps
 
 warnings.filterwarnings('ignore')
@@ -55,7 +54,7 @@ UNIT_DATA = {"km_miles": 0.621371, "miles_km": 1.60934, "kg_pounds": 2.20462, "p
 
 # ======== 模拟执行 ========
 MOCK_RESULTS = {
-    "calculate_math": lambda args: {"result": str(eval(str(args.get("expression", "0")).replace("^", "**").replace("×", "*").replace("÷", "/").replace("−", "-").replace("（", "(").replace("）", ")"), {"__builtins__": {}, "math": math}))},
+    "calculate_math": lambda args: {"result": str(safe_math_eval(args.get("expression", "0")))},
     "unit_converter": lambda args: {"result": round(float(args.get("value", 0)) * UNIT_DATA.get(f"{args.get('from_unit', '').lower()}_{args.get('to_unit', '').lower()}", 1), 4)},
     "get_current_weather": lambda args: (lambda w: {"city": args.get("location"), "temperature": w[0], "humidity": "65%", "condition": w[1]})(WEATHER_DATA.get(args.get("location"), ("22°C", "晴"))),
     "get_current_time": lambda args: {"datetime": TIME_DATA.get(args.get("timezone", "Asia/Shanghai"), "2025-03-07 14:30:00"), "timezone": args.get("timezone", "Asia/Shanghai")},
@@ -85,14 +84,9 @@ def execute_tool(name, args):
     fn = MOCK_RESULTS.get(name)
     if not fn: return None
     try:
-        signal.signal(signal.SIGALRM, lambda *_: (_ for _ in ()).throw(TimeoutError()))
-        signal.alarm(1)
         return fn(args)
-    except:
+    except Exception:
         return None
-    finally:
-        try: signal.alarm(0)
-        except: pass
 
 # ======== 多轮 Rollout ========
 def rollout_single(rollout_engine, tokenizer, messages, tools, max_turns=3, max_new_tokens=256, thinking_ratio=0.5, device="cuda"):
@@ -278,9 +272,10 @@ def rl_train_epoch(epoch, loader, iters, rollout_engine, ref_model, reward_model
 
         rewards = calculate_rewards(prompts, completions, gt_batch, tools_batch, args.num_generations, reward_model, device=args.device, turn_outputs_batch=turn_outputs_batch, unfinished_batch=unfinished_batch)
 
-        model_unwrapped = model.module if isinstance(model, DistributedDataParallel) else model
         with autocast_ctx:
-            res = model_unwrapped(input_ids, attention_mask=full_mask)
+            # 反向传播必须经过 DDP 包装后的模块：直接调用 .module 会跳过
+            # DDP 的 prepare_for_backward，梯度不会 all-reduce，各卡静默发散。
+            res = model(input_ids, attention_mask=full_mask)
             aux_loss = res.aux_loss if lm_config.use_moe else torch.tensor(0.0, device=args.device)
             logits = res.logits[:, :-1, :]
             per_token_logps = F.log_softmax(logits, dim=-1).gather(2, input_ids[:, 1:].unsqueeze(-1)).squeeze(-1)

trainer/train_dapo.py

@@ -0,0 +1,421 @@
+import os
+import sys
+
+__package__ = "trainer"
+sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
+
+import argparse
+import re
+import warnings
+import torch
+import torch.distributed as dist
+import torch.nn.functional as F
+from transformers import AutoTokenizer
+from contextlib import nullcontext
+from torch import optim
+from torch.nn.parallel import DistributedDataParallel
+from torch.utils.data import DataLoader, DistributedSampler
+from torch.nn.utils import clip_grad_norm_
+from torch.optim.lr_scheduler import CosineAnnealingLR
+from transformers import AutoModel
+from model.model_minimind import MiniMindConfig, MiniMindForCausalLM
+from dataset.lm_dataset import RLAIFDataset
+from trainer.trainer_utils import Logger, is_main_process, lm_checkpoint, init_distributed_mode, setup_seed, SkipBatchSampler, init_model
+
+warnings.filterwarnings('ignore')
+
+
+def calculate_rewards(prompts, responses, reward_model, reward_tokenizer, args):
+    """
+    计算复杂奖励，包含格式奖励、模型打分以及 DAPO 特有的长度惩罚。
+    输入的 prompts/responses 已经是展开后的（batch_size * group_size）条目。
+    """
+    def reasoning_model_reward(rewards):
+        # 1. 结构化格式奖励
+        pattern  = r"^<think>\n.*?\n</think>\n<answer>\n.*?\n</answer>$"
+        pattern2 = r"^<think>\n.*?\n</think>\n\n<answer>\n.*?\n</answer>$"
+        matches_pattern  = [re.match(pattern,  r, re.S) for r in responses]
+        matches_pattern2 = [re.match(pattern2, r, re.S) for r in responses]
+        format_rewards = [0.5 if (m1 or m2) else 0.0
+                         for m1, m2 in zip(matches_pattern, matches_pattern2)]
+        rewards += torch.tensor(format_rewards, device=args.device)
+
+        # 2. 标签存在奖励
+        def mark_num(text):
+            reward = 0
+            for tag in ["<think>", "</think>", "<answer>", "</answer>"]:
+                if text.count(tag) == 1:
+                    reward += 0.25
+            return reward
+
+        mark_rewards = [mark_num(r) for r in responses]
+        rewards += torch.tensor(mark_rewards, device=args.device)
+        return rewards
+
+    rewards = torch.zeros(len(responses), device=args.device)
+
+    if args.reasoning == 1:
+        rewards = reasoning_model_reward(rewards)
+
+    # 3. 超长惩罚 (Overlong Punishment - DAPO 特性)
+    len_penalty = []
+    for resp in responses:
+        curr_len = len(resp)
+        if curr_len > args.length_threshold:
+            penalty = -args.length_penalty * ((curr_len - args.length_threshold) / 100)
+            len_penalty.append(max(penalty, -1.0))
+        else:
+            len_penalty.append(0.0)
+    rewards += torch.tensor(len_penalty, device=args.device)
+
+    # 4. 奖励模型评分
+    with torch.no_grad():
+        reward_model_scores = []
+        for prompt, response in zip(prompts, responses):
+            pattern = r"<\|im_start\|>(system|user|assistant)\s+(.*?)<\|im_end\|>"
+            matches = re.findall(pattern, prompt, re.DOTALL)
+            messages = [{"role": role, "content": content.strip()} for role, content in matches]
+
+            tmp_chat = messages + [{"role": "assistant", "content": response}]
+            score = reward_model.get_score(reward_tokenizer, tmp_chat)
+            scale = 3.0
+            score = max(min(score, scale), -scale)
+
+            if args.reasoning == 1:
+                answer_match = re.search(r'<answer>(.*?)</answer>', response, re.DOTALL)
+                if answer_match:
+                    answer_content = answer_match.group(1).strip()
+                    tmp_chat = messages + [{"role": "assistant", "content": answer_content}]
+                    answer_score = reward_model.get_score(reward_tokenizer, tmp_chat)
+                    answer_score = max(min(answer_score, scale), -scale)
+                    score = score * 0.4 + answer_score * 0.6
+            reward_model_scores.append(score)
+
+        reward_model_scores = torch.tensor(reward_model_scores, device=args.device)
+        rewards += reward_model_scores
+
+    return rewards
+
+
+def dapo_train_epoch(epoch, loader, iters, old_actor_model, ref_model,
+                     actor_scheduler, reward_model, reward_tokenizer,
+                     start_step=0, wandb=None):
+    actor_model.train()
+
+    for step, batch in enumerate(loader, start=start_step + 1):
+        prompts    = batch["prompt"]
+        batch_size = len(prompts)
+        G          = args.group_size
+
+        # 每个 prompt 重复 G 次，展开为 (batch_size * G) 条输入
+        prompts_expanded = [p for p in prompts for _ in range(G)]
+
+        enc = tokenizer(
+            prompts_expanded,
+            return_tensors="pt",
+            padding=True,
+            truncation=True,
+            max_length=args.max_seq_len,
+            padding_side="left"
+        ).to(args.device)
+        prompt_length = enc.input_ids.shape[1]
+
+        with torch.no_grad():
+            model_for_gen = actor_model.module if isinstance(actor_model, DistributedDataParallel) else actor_model
+            gen_out = model_for_gen.generate(
+                input_ids=enc.input_ids,
+                attention_mask=enc.attention_mask,
+                max_new_tokens=args.max_gen_len,
+                do_sample=True,
+                temperature=0.8,
+                pad_token_id=tokenizer.pad_token_id,
+                eos_token_id=tokenizer.eos_token_id,
+            )
+
+        # gen_out: (batch_size * G, seq_len)
+        responses_text = [
+            tokenizer.decode(gen_out[i, prompt_length:], skip_special_tokens=True)
+            for i in range(len(prompts_expanded))
+        ]
+        rewards_flat = calculate_rewards(prompts_expanded, responses_text, reward_model, reward_tokenizer, args)
+        # rewards_flat: (batch_size * G,)
+
+        # ------------------------------------------------------------------
+        # advantage = (r - mean_group) / std_group
+        # ------------------------------------------------------------------
+        rewards_grouped = rewards_flat.view(batch_size, G)
+        mean_r          = rewards_grouped.mean(dim=1, keepdim=True)
+        std_r           = rewards_grouped.std(dim=1, keepdim=True).clamp(min=1e-8)
+        advantages      = ((rewards_grouped - mean_r) / std_r).view(-1)  # (batch_size * G,)
+
+        # ------------------------------------------------------------------
+        # Dynamic Sampling
+        # ------------------------------------------------------------------
+        if args.use_dynamic_sampling == 1:
+            if (std_r < 1e-6).all().item():
+                if is_main_process():
+                    Logger(f"Step {step}: All groups have zero reward variance, skipping...")
+                continue
+
+        # ------------------------------------------------------------------
+        # Actor forward
+        # ------------------------------------------------------------------
+        full_mask = (gen_out != tokenizer.pad_token_id).long()
+
+        with autocast_ctx:
+            res      = actor_model(input_ids=gen_out, attention_mask=full_mask)
+            logits   = res.logits
+            aux_loss = res.aux_loss if lm_config.use_moe else torch.tensor(0.0, device=args.device)
+
+        labels      = gen_out[:, 1:].clone()
+        logp_tokens = F.log_softmax(logits[:, :-1], dim=-1).gather(2, labels.unsqueeze(-1)).squeeze(-1)
+
+        seq_len    = gen_out.size(1) - 1
+        resp_mask  = torch.arange(seq_len, device=gen_out.device).unsqueeze(0) >= prompt_length - 1
+        final_mask = resp_mask & (~labels.eq(tokenizer.pad_token_id))
+
+        # Token-level 平均 log-prob（防止长回复主导梯度）
+        token_count = final_mask.sum(dim=1).clamp(min=1).float()
+        actor_logp  = (logp_tokens * final_mask).sum(dim=1) / token_count
+
+        with torch.no_grad():
+            old_logits      = old_actor_model(input_ids=gen_out, attention_mask=full_mask).logits
+            old_logp_tokens = F.log_softmax(old_logits[:, :-1], dim=-1).gather(2, labels.unsqueeze(-1)).squeeze(-1)
+            old_logp        = (old_logp_tokens * final_mask).sum(dim=1) / token_count
+
+            ref_logits      = ref_model(input_ids=gen_out, attention_mask=full_mask).logits
+            ref_logp_tokens = F.log_softmax(ref_logits[:, :-1], dim=-1).gather(2, labels.unsqueeze(-1)).squeeze(-1)
+            ref_logp        = (ref_logp_tokens * final_mask).sum(dim=1) / token_count
+
+        kl     = (actor_logp - old_logp).mean()
+        kl_ref = (actor_logp - ref_logp).mean()
+        ratio  = torch.exp(actor_logp - old_logp)
+
+        # ------------------------------------------------------------------
+        # Decoupled Clip
+        #   Adv > 0：只限上界，允许正向大步更新prompts_expanded = [p for p in prompts for _ in range(G)]
+        #   Adv ≤ 0：只限下界，防止负向更新反弹
+        # ------------------------------------------------------------------
+        surr1 = ratio * advantages
+        clipped_ratio = torch.where(
+            advantages > 0,
+            torch.clamp(ratio, max=1.0 + args.clip_epsilon_high),
+            torch.clamp(ratio, min=1.0 - args.clip_epsilon_low),
+        )
+        surr2       = clipped_ratio * advantages
+        policy_loss = -torch.min(surr1, surr2).mean()
+
+        loss = (policy_loss + args.kl_coef * kl_ref + aux_loss) / args.accumulation_steps
+        loss.backward()
+
+        if (step + 1) % args.accumulation_steps == 0:
+            clip_grad_norm_(actor_model.parameters(), args.grad_clip)
+            actor_optimizer.step()
+            actor_scheduler.step()
+            actor_optimizer.zero_grad()
+
+        if is_main_process():
+            response_ids = gen_out[:, enc.input_ids.shape[1]:]
+            is_eos       = (response_ids == tokenizer.eos_token_id)
+            eos_indices  = torch.argmax(is_eos.int(), dim=1)
+            lengths = torch.where(
+                is_eos.any(dim=1),
+                eos_indices + 1,
+                torch.tensor(response_ids.shape[1], device=is_eos.device)
+            )
+            avg_len    = lengths.float().mean()
+            reward_std = rewards_flat.std().item()
+
+            if wandb is not None:
+                wandb.log({
+                    "actor_loss":       policy_loss.item(),
+                    "reward":           rewards_flat.mean().item(),
+                    "reward_std":       reward_std,
+                    "kl":               kl.item(),
+                    "kl_ref":           kl_ref.item(),
+                    "avg_response_len": avg_len.item(),
+                    "actor_lr":         actor_optimizer.param_groups[0]['lr'],
+                })
+
+            Logger(
+                f"Epoch:[{epoch + 1}/{args.epochs}]({step}/{iters}), "
+                f"Loss: {policy_loss.item():.4f}, Reward: {rewards_flat.mean().item():.4f}, "
+                f"KL: {kl.item():.4f}, Len: {avg_len.item():.2f}"
+            )
+
+        if (step + 1) % args.update_old_actor_freq == 0:
+            raw_actor = actor_model.module if isinstance(actor_model, DistributedDataParallel) else actor_model
+            raw_actor = getattr(raw_actor, '_orig_mod', raw_actor)
+            old_actor_model.load_state_dict({k: v.detach().cpu() for k, v in raw_actor.state_dict().items()})
+            old_actor_model.to(args.device)
+
+        if (step % args.save_interval == 0 or step == iters - 1) and is_main_process():
+            actor_model.eval()
+            moe_suffix = '_moe' if lm_config.use_moe else ''
+            ckp = f'{args.save_dir}/{args.save_weight}_{lm_config.hidden_size}{moe_suffix}.pth'
+            raw_actor = actor_model.module if isinstance(actor_model, DistributedDataParallel) else actor_model
+            raw_actor = getattr(raw_actor, '_orig_mod', raw_actor)
+            torch.save({k: v.half().cpu() for k, v in raw_actor.state_dict().items()}, ckp)
+            lm_checkpoint(
+                lm_config, weight=args.save_weight, model=actor_model,
+                optimizer=actor_optimizer, epoch=epoch, step=step,
+                wandb=wandb, save_dir='../checkpoints', scheduler=actor_scheduler,
+            )
+            actor_model.train()
+
+        del enc, gen_out, responses_text, rewards_flat, rewards_grouped
+        del advantages, full_mask, logits, labels, logp_tokens, final_mask, token_count
+        del actor_logp, old_logits, old_logp, ref_logits, ref_logp
+        del kl, kl_ref, ratio, surr1, surr2, clipped_ratio, policy_loss, loss
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(
+        description="MiniMind DAPO (Decoupled Clip and Dynamic Sampling Policy Optimization)"
+    )
+    parser.add_argument("--save_dir",              type=str,   default="../out",                      help="模型保存目录")
+    parser.add_argument('--save_weight',            type=str,   default='dapo',                  help="保存权重的前缀名")
+    parser.add_argument("--epochs",                type=int,   default=1,                             help="训练轮数")
+    parser.add_argument("--batch_size",            type=int,   default=2,                             help="prompt 级别的 batch size（实际前向 = batch_size * group_size）")
+    parser.add_argument("--learning_rate",         type=float, default=8e-8,                          help="Actor 学习率")
+    parser.add_argument("--device",                type=str,   default="cuda:0" if torch.cuda.is_available() else "cpu", help="训练设备")
+    parser.add_argument("--dtype",                 type=str,   default="bfloat16",                    help="混合精度类型")
+    parser.add_argument("--num_workers",           type=int,   default=8,                             help="数据加载线程数")
+    parser.add_argument("--accumulation_steps",    type=int,   default=1,                             help="梯度累积步数")
+    parser.add_argument("--grad_clip",             type=float, default=1.0,                           help="梯度裁剪阈值")
+    parser.add_argument("--log_interval",          type=int,   default=1,                             help="日志打印间隔")
+    parser.add_argument("--save_interval",         type=int,   default=10,                            help="模型保存间隔")
+    parser.add_argument('--hidden_size',            type=int,   default=512,                           help="隐藏层维度")
+    parser.add_argument('--num_hidden_layers',      type=int,   default=8,                             help="隐藏层数量")
+    parser.add_argument('--use_moe',                type=int,   default=0,  choices=[0, 1],            help="是否使用 MoE 架构（0=否，1=是）")
+    parser.add_argument('--max_seq_len',            type=int,   default=66,                            help="Prompt 最大长度")
+    parser.add_argument("--max_gen_len",            type=int,   default=1024,                          help="生成的最大长度")
+    parser.add_argument("--data_path",              type=str,   default="../dataset/rlaif-mini.jsonl", help="RLAIF 数据路径")
+
+    # DAPO 核心参数
+    parser.add_argument("--clip_epsilon_low",      type=float, default=0.1,  help="Decoupled Clip 下界")
+    parser.add_argument("--clip_epsilon_high",     type=float, default=0.2,  help="Decoupled Clip 上界")
+    parser.add_argument("--group_size",            type=int,   default=8,    help="每个 prompt 的采样回复数")
+    parser.add_argument("--use_dynamic_sampling",  type=int,   default=1,   choices=[0, 1], help="是否开启动态采样过滤")
+    parser.add_argument("--length_penalty",        type=float, default=0.1,  help="长度惩罚系数")
+    parser.add_argument("--length_threshold",      type=int,   default=1200, help="触发长度惩罚的字符阈值")
+    parser.add_argument("--kl_coef",               type=float, default=0.02, help="KL 散度惩罚系数（相对 ref_model）")
+    parser.add_argument("--reasoning",             type=int,   default=1,   choices=[0, 1], help="推理模型类型（0=普通模型，1=推理模型）")
+    parser.add_argument("--update_old_actor_freq", type=int,   default=4,   help="更新 old_actor_model 的频率（步数）")
+    parser.add_argument("--reward_model_path",     type=str,   default="../../internlm2-1_8b-reward", help="Reward 模型路径")
+    parser.add_argument('--from_resume',            type=int,   default=0,   choices=[0, 1], help="是否自动检测并续训（0=否，1=是）")
+    parser.add_argument("--use_wandb",             action="store_true",                     help="是否使用 wandb/swanlab")
+    parser.add_argument("--wandb_project",         type=str,   default="MiniMind-DAPO",     help="wandb 项目名")
+    parser.add_argument("--use_compile",           type=int,   default=0,   choices=[0, 1], help="是否使用 torch.compile 加速（0=否，1=是）")
+    args = parser.parse_args()
+
+    # ========== 1. 初始化环境和随机种子 ==========
+    local_rank = init_distributed_mode()
+    if dist.is_initialized():
+        args.device = f"cuda:{local_rank}"
+    setup_seed(42 + (dist.get_rank() if dist.is_initialized() else 0))
+
+    # ========== 2. 配置目录、模型参数、检查 ckp ==========
+    os.makedirs(args.save_dir, exist_ok=True)
+    lm_config = MiniMindConfig(
+        hidden_size=args.hidden_size,
+        num_hidden_layers=args.num_hidden_layers,
+        use_moe=bool(args.use_moe)
+    )
+    ckp_data = lm_checkpoint(lm_config, weight=args.save_weight, save_dir='../checkpoints') \
+               if args.from_resume == 1 else None
+
+    # ========== 3. 设置混合精度 ==========
+    device_type  = "cuda" if "cuda" in args.device else "cpu"
+    dtype        = torch.bfloat16 if args.dtype == "bfloat16" else torch.float16
+    autocast_ctx = nullcontext() if device_type == "cpu" else torch.cuda.amp.autocast(dtype=dtype)
+
+    # ========== 4. 配 wandb (SwanLab) ==========
+    wandb = None
+    if args.use_wandb and is_main_process():
+        import swanlab as wandb
+        wandb_id = ckp_data.get('wandb_id') if ckp_data else None
+        resume   = 'must' if wandb_id else None
+        wandb.init(
+            project=args.wandb_project,
+            name=f"MiniMind-DAPO-{args.learning_rate}",
+            id=wandb_id,
+            resume=resume,
+        )
+
+    # ========== 5. 初始化模型 ==========
+    base_weight = "reason" if args.reasoning == 1 else "full_sft"
+
+    actor_model, tokenizer = init_model(lm_config, base_weight, device=args.device)
+    if args.use_compile == 1:
+        actor_model = torch.compile(actor_model)
+
+    old_actor_model, _ = init_model(lm_config, base_weight, device=args.device)
+    old_actor_model = old_actor_model.eval().requires_grad_(False)
+
+    ref_model, _ = init_model(lm_config, base_weight, device=args.device)
+    ref_model = ref_model.eval().requires_grad_(False)
+
+    reward_model = AutoModel.from_pretrained(
+        args.reward_model_path,
+        torch_dtype=torch.float16,
+        trust_remote_code=True,
+    )
+    reward_model = reward_model.to(args.device).eval().requires_grad_(False)
+    reward_tokenizer = AutoTokenizer.from_pretrained(args.reward_model_path, trust_remote_code=True)
+
+    # ========== 6. 数据、优化器、调度器 ==========
+    train_ds        = RLAIFDataset(args.data_path, tokenizer, max_length=(args.max_seq_len + args.max_gen_len))
+    train_sampler   = DistributedSampler(train_ds) if dist.is_initialized() else None
+    actor_optimizer = optim.AdamW(actor_model.parameters(), lr=args.learning_rate)
+
+    iters           = len(DataLoader(train_ds, batch_size=args.batch_size, sampler=train_sampler))
+    total_steps     = (iters // args.accumulation_steps) * args.epochs
+    actor_scheduler = CosineAnnealingLR(actor_optimizer, T_max=total_steps, eta_min=args.learning_rate / 10)
+
+    if ckp_data:
+        actor_model.load_state_dict(ckp_data['model'])
+        actor_optimizer.load_state_dict(ckp_data['optimizer'])
+        actor_scheduler.load_state_dict(ckp_data['scheduler'])
+        start_epoch = ckp_data['epoch']
+        start_step  = ckp_data.get('step', 0)
+    else:
+        start_epoch, start_step = 0, 0
+
+    if dist.is_initialized():
+        actor_model = DistributedDataParallel(actor_model, device_ids=[local_rank])
+        old_actor_model.to(args.device)
+
+    # ========== 7. 打印配置摘要 ==========
+    if is_main_process():
+        Logger("=" * 60)
+        Logger("DAPO Training Config (Critic-free):")
+        Logger(f"  group_size           = {args.group_size}")
+        Logger(f"  clip_epsilon_low     = {args.clip_epsilon_low}")
+        Logger(f"  clip_epsilon_high    = {args.clip_epsilon_high}")
+        Logger(f"  use_dynamic_sampling = {args.use_dynamic_sampling}")
+        Logger(f"  kl_coef              = {args.kl_coef}")
+        Logger(f"  effective_batch      = {args.batch_size} prompts × {args.group_size} = {args.batch_size * args.group_size}")
+        Logger("=" * 60)
+
+    # ========== 8. 开始训练 ==========
+    for epoch in range(start_epoch, args.epochs):
+        train_sampler and train_sampler.set_epoch(epoch)
+        setup_seed(42 + epoch)
+        indices = torch.randperm(len(train_ds)).tolist()
+        skip    = start_step if (epoch == start_epoch and start_step > 0) else 0
+        loader  = DataLoader(
+            train_ds,
+            batch_sampler=SkipBatchSampler(train_sampler or indices, args.batch_size, skip),
+            num_workers=args.num_workers,
+            pin_memory=True,
+        )
+        dapo_train_epoch(
+            epoch, loader, len(loader),
+            old_actor_model, ref_model,
+            actor_scheduler, reward_model, reward_tokenizer,
+            skip, wandb,
+        )
+
+    if dist.is_initialized():
+        dist.destroy_process_group()

trainer/train_grpo.py

@@ -95,9 +95,10 @@ def grpo_train_epoch(epoch, loader, iters, rollout_engine, ref_model, reward_mod
 
         rewards = calculate_rewards(prompts, completions, reward_model).to(args.device)  # [B*num_gen]
 
-        model_unwrapped = model.module if isinstance(model, DistributedDataParallel) else model
         with autocast_ctx:
-            res = model_unwrapped(outputs, attention_mask=full_mask)
+            # 反向传播必须经过 DDP 包装后的模块：直接调用 .module 会跳过
+            # DDP 的 prepare_for_backward，梯度不会 all-reduce，各卡静默发散。
+            res = model(outputs, attention_mask=full_mask)
             aux_loss = res.aux_loss if lm_config.use_moe else torch.tensor(0.0, device=args.device)
             per_token_logps = F.log_softmax(res.logits[:, :-1, :], dim=-1).gather(2, outputs[:, 1:].unsqueeze(-1)).squeeze(-1).gather(1, logp_pos)
 

trainer/train_ppo.py

@@ -159,8 +159,6 @@ def ppo_train_epoch(epoch, loader, iters, rollout_engine, ref_model, actor_sched
         clipfrac_sum = 0.0
         aux_loss_sum = 0.0
         log_count = 0
-        actor_unwrapped = actor_model.module if isinstance(actor_model, DistributedDataParallel) else actor_model
-        critic_unwrapped = critic_model.module if isinstance(critic_model, DistributedDataParallel) else critic_model
         for ppo_epoch in range(args.ppo_update_iters):
             if stop_ppo:
                 break
@@ -168,11 +166,13 @@ def ppo_train_epoch(epoch, loader, iters, rollout_engine, ref_model, actor_sched
             for i in range(0, B, mb_size):
                 inds = b_inds[i:i + mb_size]
                 
-                mb_values_seq = critic_unwrapped(input_ids=gen_out[inds], attention_mask=full_mask[inds])
+                # 反向传播必须经过 DDP 包装后的模块：直接调用 .module 会跳过
+                # DDP 的 prepare_for_backward，梯度不会 all-reduce，各卡静默发散。
+                mb_values_seq = critic_model(input_ids=gen_out[inds], attention_mask=full_mask[inds])
                 mb_resp_values = mb_values_seq.gather(1, logp_pos[inds])
 
                 with autocast_ctx:
-                    res = actor_unwrapped(input_ids=gen_out[inds], attention_mask=full_mask[inds])
+                    res = actor_model(input_ids=gen_out[inds], attention_mask=full_mask[inds])
                     aux_loss = res.aux_loss if lm_config.use_moe else torch.tensor(0.0, device=args.device)
                     # 在 autocast 内计算 log_softmax，避免直接对 fp16/bf16 logits
                     # 计算造成额外数值偏差。
@@ -191,7 +191,7 @@ def ppo_train_epoch(epoch, loader, iters, rollout_engine, ref_model, actor_sched
                                f"ratio_max={torch.exp(_lrv).max().item():.6f} "
                                f"ratio_min={torch.exp(_lrv).min().item():.6f} "
                                f"dropout={getattr(lm_config, 'dropout', None)} "
-                               f"training={actor_unwrapped.training}")
+                               f"training={actor_model.training}")
                 approx_kl = (0.5 * (log_ratio ** 2) * resp_policy_mask[inds]).sum() / resp_policy_mask[inds].sum().clamp(min=1)
                 
                 # 同步各卡的 approx_kl，防止某卡 break 而其它卡继续导致 DDP 死锁

trainer/trainer_utils.py

@@ -5,6 +5,8 @@ import os
 import sys
 __package__ = "trainer"
 sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
+import ast
+import operator
 import random
 import math
 import numpy as np
@@ -174,4 +176,34 @@ class LMForRewardModel:
             {"role": "assistant", "content": response}
         ]
         score = self.model.get_score(self.tokenizer, eval_messages)
-        return max(min(score, 3.0), -3.0)
+        return max(min(score, 3.0), -3.0)
+
+
+# ===== 数学表达式安全求值：替代 eval，只放行算术运算与 math 白名单（长度上限 512） =====
+def safe_math_eval(expression):
+    """对模型生成的数学表达式求值：支持 + - * / // % **、math 白名单函数与 pi/e/tau 常量。"""
+    def pow_guard(base, exp):  # 幂运算统一走这里，拦截 9**9**9 / 10**99999 这类把进程算死的输入
+        if abs(exp) > 1e4 or (abs(base) > 1 and abs(exp) * math.log10(abs(base)) > 100): raise ValueError('幂运算结果过大')
+        return base ** exp
+    def resolve(node):  # 同时兼容 sqrt(4) 与 math.sqrt(4) 两种写法
+        if isinstance(node, ast.Name): return node.id
+        if isinstance(node, ast.Attribute) and getattr(node.value, 'id', '') == 'math': return node.attr
+    def walk(node):
+        if isinstance(node, ast.Constant) and type(node.value) in (int, float): return node.value
+        name = resolve(node)
+        if name in consts: return consts[name]
+        if isinstance(node, ast.UnaryOp): return unary_ops[type(node.op)](walk(node.operand))
+        if isinstance(node, ast.BinOp): return bin_ops[type(node.op)](walk(node.left), walk(node.right))
+        if isinstance(node, ast.Call) and not node.keywords: return funcs[resolve(node.func)](*map(walk, node.args))
+        raise ValueError(f'不支持的表达式语法: {type(node).__name__}')
+    consts = {'pi': math.pi, 'e': math.e, 'tau': math.tau}
+    funcs = {'pow': pow_guard, **{n: getattr(math, n) for n in 'sqrt exp log log2 log10 sin cos tan asin acos atan atan2 sinh cosh tanh floor ceil trunc fabs fmod hypot gcd degrees radians'.split()}}
+    bin_ops = {ast.Add: operator.add, ast.Sub: operator.sub, ast.Mult: operator.mul, ast.Div: operator.truediv, ast.FloorDiv: operator.floordiv, ast.Mod: operator.mod, ast.Pow: pow_guard}
+    unary_ops = {ast.UAdd: operator.pos, ast.USub: operator.neg}
+    chars = str.maketrans({'^': '**', '×': '*', '÷': '/', '−': '-', '²': '**2', '³': '**3', '（': '(', '）': ')'})
+    expr = str(expression).translate(chars).strip()
+    if not expr or len(expr) > 512: raise ValueError('表达式为空或过长')
+    try:
+        return walk(ast.parse(expr, mode='eval').body)
+    except (KeyError, SyntaxError, TypeError):
+        raise ValueError('不支持的表达式语法') from None