[inference] add smooth function and delete useless code for smoothquant (#4895)

* add smooth function and delete useless code

* update datasets

* remove duplicate import

* delete useless file

Author: Xu-Kai

colossalai/inference/quant/smoothquant/calibration.py

@@ -4,71 +4,31 @@
 import types
 import warnings
 from abc import abstractmethod
+from functools import partial
 from os.path import isdir, isfile, join
 from typing import Dict, List, Optional, Union
 
 import accelerate
+import numpy as np
 import torch
 import torch.nn as nn
 import transformers
 from safetensors.torch import save_file as safe_save
 from torch import device
+from tqdm import tqdm
 from transformers import AutoConfig, AutoModelForCausalLM, PreTrainedModel
 from transformers.modeling_utils import no_init_weights
 from transformers.utils.generic import ContextManagers
 from transformers.utils.hub import PushToHubMixin, cached_file
 
-from ....tensor_parallel.batch_infer_state import BatchInferState
-from ....tensor_parallel.kvcache_manager import MemoryManager
+from colossalai.inference.tensor_parallel.batch_infer_state import BatchInferState
+from colossalai.inference.tensor_parallel.kvcache_manager import MemoryManager
 
 CPU = device("cpu")
-CUDA_0 = device("cuda:0")
 
 SUPPORTED_MODELS = ["llama"]
 
 
-def get_module_by_name_suffix(model, module_name: str):
-    for name, module in model.named_modules():
-        if name.endswith(module_name):
-            return module
-
-
-def simple_dispatch_model(model, device_map):
-    from accelerate.hooks import AlignDevicesHook, add_hook_to_module
-
-    if "" in device_map:
-        d = device_map[""]
-        model = model.to(torch.device(d))
-        model.hf_device_map = device_map
-        return model
-
-    tied_params = accelerate.utils.modeling.find_tied_parameters(model)
-    if set(device_map.values()) == {"cpu"} or set(device_map.values()) == {"cpu", "disk"}:
-        main_device = "cpu"
-    else:
-        main_device = [d for d in device_map.values() if d not in ["cpu", "disk"]][0]
-
-    cpu_offload_group = [(n, d) for n, d in device_map.items() if d == "cpu"]
-    prev_hook = None
-    for idx, (n, d) in enumerate(cpu_offload_group):
-        m = get_module_by_name_suffix(model, n)
-        _, prev_hook = accelerate.cpu_offload_with_hook(m, execution_device=main_device, prev_module_hook=prev_hook)
-    # set first cpu offload module's prev_module_hook to the last cpu offload module's hook
-    if len(cpu_offload_group) > 1:
-        get_module_by_name_suffix(model, cpu_offload_group[0][0])._hf_hook.prev_module_hook = prev_hook
-
-    for n, d in device_map.items():
-        m = get_module_by_name_suffix(model, n)
-        if d != "cpu":
-            d = torch.device(d)
-            hook = AlignDevicesHook(d, io_same_device=True, place_submodules=True)
-            add_hook_to_module(m, hook)
-    accelerate.utils.modeling.retie_parameters(model, tied_params)
-    model.hf_device_map = device_map
-
-    return model
-
-
 class BaseSmoothForCausalLM(nn.Module, PushToHubMixin):
     layer_type: str = None
 
@@ -132,6 +92,7 @@ def init_batch_state(self, max_output_len=256, **kwargs):
         batch_infer_state.past_key_values_len = 0
         batch_infer_state.is_context_stage = True
         batch_infer_state.set_cache_manager(self.cache_manager)
+        batch_infer_state.cache_manager.free_all()
         return batch_infer_state
 
     @abstractmethod
@@ -157,15 +118,79 @@ def generate(self, **kwargs):
         if self.config.model_type == "llama":
             setattr(self.model.model, "infer_state", batch_infer_state)
 
-        batch_infer_state.is_context_stage = True
-
         with torch.inference_mode():
             return self.model.generate(**kwargs)
 
     def prepare_inputs_for_generation(self, *args, **kwargs):
         """shortcut for model.prepare_inputs_for_generation"""
         return self.model.prepare_inputs_for_generation(*args, **kwargs)
 
+    def collect_act_scales(self, model, tokenizer, dataset, device, num_samples=512, seq_len=512):
+        for text in tqdm(dataset):
+            input_ids = tokenizer(text, return_tensors="pt", max_length=seq_len, truncation=True).input_ids.to(device)
+            model(input_ids)
+
+    def collect_act_dict(self, model, tokenizer, dataset, act_dict, device, num_samples=512, seq_len=512):
+        pbar = tqdm(dataset)
+        for text in pbar:
+            input_ids = tokenizer(text, return_tensors="pt", max_length=seq_len, truncation=True).input_ids.to(device)
+            model(input_ids)
+            mean_scale = np.mean([v["input"] for v in act_dict.values()])
+            pbar.set_description(f"Mean input scale: {mean_scale:.2f}")
+
+    def get_act_scales(self, model, tokenizer, dataset, num_samples=512, seq_len=512):
+        model.eval()
+        device = next(model.parameters()).device
+        act_scales = {}
+
+        def stat_tensor(name, tensor):
+            hidden_dim = tensor.shape[-1]
+            tensor = tensor.view(-1, hidden_dim).abs().detach()
+            comming_max = torch.max(tensor, dim=0)[0].float().cpu()
+            if name in act_scales:
+                act_scales[name] = torch.max(act_scales[name], comming_max)
+            else:
+                act_scales[name] = comming_max
+
+        def stat_input_hook(m, x, y, name):
+            if isinstance(x, tuple):
+                x = x[0]
+            stat_tensor(name, x)
+
+        hooks = []
+        for name, m in model.named_modules():
+            if isinstance(m, nn.Linear):
+                hooks.append(m.register_forward_hook(partial(stat_input_hook, name=name)))
+
+        self.collect_act_scales(model, tokenizer, dataset, device, num_samples, seq_len)
+
+        for h in hooks:
+            h.remove()
+
+        return act_scales
+
+    @torch.no_grad()
+    def smooth_ln_fcs(self, ln, fcs, act_scales, alpha=0.5):
+        if not isinstance(fcs, list):
+            fcs = [fcs]
+        for fc in fcs:
+            assert isinstance(fc, nn.Linear)
+            assert ln.weight.numel() == fc.in_features == act_scales.numel()
+
+        device, dtype = fcs[0].weight.device, fcs[0].weight.dtype
+        act_scales = act_scales.to(device=device, dtype=dtype)
+        weight_scales = torch.cat([fc.weight.abs().max(dim=0, keepdim=True)[0] for fc in fcs], dim=0)
+        weight_scales = weight_scales.max(dim=0)[0].clamp(min=1e-5)
+
+        scales = (act_scales.pow(alpha) / weight_scales.pow(1 - alpha)).clamp(min=1e-5).to(device).to(dtype)
+
+        ln.weight.div_(scales)
+        if hasattr(ln, "bias"):
+            ln.bias.div_(scales)
+
+        for fc in fcs:
+            fc.weight.mul_(scales.view(1, -1))
+
     def save_quantized(
         self,
         save_dir: str,

colossalai/inference/quant/smoothquant/models/base_model.py

@@ -7,14 +7,10 @@
 from functools import partial
 from typing import List, Optional, Tuple, Union
 
-import numpy as np
 import torch
 import torch.nn as nn
 import torch.nn.functional as F
-from datasets import load_dataset
-from torch import nn
 from torch_int.nn.bmm import BMM_S8T_S8N_F32T, BMM_S8T_S8N_S8T
-from tqdm import tqdm
 from transformers import PreTrainedModel
 from transformers.modeling_outputs import BaseModelOutputWithPast
 from transformers.models.llama.configuration_llama import LlamaConfig
@@ -756,15 +752,14 @@ class SmoothLlamaForCausalLM(BaseSmoothForCausalLM):
     def __init__(self, model: PreTrainedModel, quantized: bool = False):
         super().__init__(model, quantized)
 
-    def quantized(
+    def get_act_dict(
         self,
         tokenizer,
-        dataset_path,
+        dataset,
         num_samples=512,
         seq_len=512,
     ):
         llama_model = self.model
-        llama_config = llama_model.config
 
         llama_model.eval()
         device = next(llama_model.parameters()).device
@@ -798,23 +793,37 @@ def stat_io_hook(m, x, y, name):
             if isinstance(m, torch.nn.Linear):
                 hooks.append(m.register_forward_hook(partial(stat_io_hook, name=name)))
 
-        print("Collecting activation scales...")
-        pbar = tqdm(range(num_samples))
-        dataset = load_dataset("json", data_files=dataset_path, split="train")
-        dataset = dataset.shuffle(seed=42)
-        for i in pbar:
-            input_ids = tokenizer(
-                dataset["rows"][0][i]["row"]["text"],
-                return_tensors="pt",
-                max_length=seq_len,
-                truncation=True,
-            ).input_ids.to(device)
-            llama_model(input_ids)
-            mean_scale = np.mean([v["input"] for v in act_dict.values()])
-            pbar.set_description(f"Mean input scale: {mean_scale:.2f}")
+        self.collect_act_dict(llama_model, tokenizer, dataset, act_dict, device, num_samples, seq_len)
+
         for hook in hooks:
             hook.remove()
+        return act_dict
+
+    def smooth_fn(self, scales, alpha=0.5):
+        model = self.model
+        for name, module in model.named_modules():
+            if isinstance(module, LlamaDecoderLayer):
+                attn_ln = module.input_layernorm
+                qkv = [module.self_attn.q_proj, module.self_attn.k_proj, module.self_attn.v_proj]
+                qkv_input_scales = scales[name + ".self_attn.q_proj"]
+                self.smooth_ln_fcs(attn_ln, qkv, qkv_input_scales, alpha)
+
+    def quantized(
+        self,
+        tokenizer,
+        dataset,
+        num_samples=512,
+        seq_len=512,
+        alpha=0.5,
+    ):
+        llama_model = self.model
+        llama_config = llama_model.config
+
+        act_scales = self.get_act_scales(llama_model, tokenizer, dataset, num_samples, seq_len)
+
+        self.smooth_fn(act_scales, alpha)
 
+        act_dict = self.get_act_dict(tokenizer, dataset, num_samples, seq_len)
         decoder_layer_scales = []
 
         for idx in range(llama_config.num_hidden_layers):