init

vllm/model_executor/models/mixtral.py

@@ -0,0 +1,583 @@
+# coding=utf-8
+# Adapted from
+# https://github.com/huggingface/transformers/blob/v4.28.0/src/transformers/models/llama/modeling_llama.py
+# Copyright 2023 The vLLM team.
+# Copyright 2022 EleutherAI and the HuggingFace Inc. team. All rights reserved.
+#
+# This code is based on EleutherAI's GPT-NeoX library and the GPT-NeoX
+# and OPT implementations in this library. It has been modified from its
+# original forms to accommodate minor architectural differences compared
+# to GPT-NeoX and OPT used by the Meta AI team that trained the model.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Inference-only Mixtral model."""
+from typing import Iterable, List, Optional, Tuple
+
+import torch
+from torch import nn
+from transformers import MixtralConfig
+
+from vllm import _custom_ops as ops
+from vllm.attention import Attention, AttentionMetadata
+from vllm.config import LoRAConfig
+from vllm.distributed import (get_tensor_model_parallel_rank,
+                              get_tensor_model_parallel_world_size,
+                              tensor_model_parallel_all_reduce)
+from vllm.model_executor.layers.fused_moe import fused_moe
+from vllm.model_executor.layers.layernorm import RMSNorm
+from vllm.model_executor.layers.linear import (QKVParallelLinear,
+                                               ReplicatedLinear,
+                                               RowParallelLinear)
+from vllm.model_executor.layers.logits_processor import LogitsProcessor
+from vllm.model_executor.layers.quantization.base_config import (
+    QuantizationConfig)
+from vllm.model_executor.layers.quantization.fp8 import Fp8Config
+from vllm.model_executor.layers.rotary_embedding import get_rope
+from vllm.model_executor.layers.sampler import Sampler
+from vllm.model_executor.layers.vocab_parallel_embedding import (
+    DEFAULT_VOCAB_PADDING_SIZE, ParallelLMHead, VocabParallelEmbedding)
+from vllm.model_executor.model_loader.weight_utils import default_weight_loader
+from vllm.model_executor.sampling_metadata import SamplingMetadata
+from vllm.model_executor.utils import set_weight_attrs
+from vllm.sequence import SamplerOutput
+from vllm.utils import print_warning_once
+
+
+class MixtralMoE(nn.Module):
+    """A tensor-parallel MoE implementation for Mixtral that shards each expert
+    across all ranks.
+
+    Each expert's weights are sharded across all ranks and a fused MoE
+    kernel is used for the forward pass, and finally we reduce the outputs
+    across ranks.
+    """
+
+    def __init__(
+        self,
+        num_experts: int,
+        top_k: int,
+        hidden_size: int,
+        intermediate_size: int,
+        params_dtype: Optional[torch.dtype] = None,
+        tp_size: Optional[int] = None,
+        quant_config: Optional[QuantizationConfig] = None,
+    ):
+        super().__init__()
+        self.tp_size = tp_size or get_tensor_model_parallel_world_size()
+        self.num_total_experts = num_experts
+        self.top_k = top_k
+        self.hidden_size = hidden_size
+        self.intermediate_size = intermediate_size // self.tp_size
+        self.quant_config = quant_config
+
+        # FIXME(pcmoritz): Make this more general to support different
+        # quantization schemes
+        self.use_fp8 = isinstance(quant_config, Fp8Config)
+
+        if params_dtype is None:
+            params_dtype = torch.get_default_dtype()
+        self.params_dtype = params_dtype
+
+        # Gate always runs at half / full precision for now.
+        self.gate = ReplicatedLinear(self.hidden_size,
+                                     self.num_total_experts,
+                                     bias=False,
+                                     params_dtype=self.params_dtype,
+                                     quant_config=None)
+
+        if self.use_fp8:
+            params_dtype = torch.float8_e4m3fn
+
+        self.w13_weight = nn.Parameter(
+            torch.empty(self.num_total_experts,
+                        2 * self.intermediate_size,
+                        self.hidden_size,
+                        dtype=params_dtype))
+        self.w2_weight = nn.Parameter(
+            torch.empty(self.num_total_experts,
+                        self.hidden_size,
+                        self.intermediate_size,
+                        dtype=params_dtype))
+
+        set_weight_attrs(self.w13_weight, {
+            "weight_loader": self.weight_loader,
+        })
+        set_weight_attrs(self.w2_weight, {
+            "weight_loader": self.weight_loader,
+        })
+
+        # Used for fp8.
+        self.w13_scale = None
+        self.w2_scale = None
+        self.a13_scale = None
+        self.a2_scale = None
+
+        if self.use_fp8:
+            # WEIGHT_SCALE (for fp8)
+            self.w13_scale = nn.Parameter(torch.ones(self.num_total_experts,
+                                                     dtype=torch.float32),
+                                          requires_grad=False)
+            self.w2_scale = nn.Parameter(torch.ones(self.num_total_experts,
+                                                    dtype=torch.float32),
+                                         requires_grad=False)
+
+            # If loading fp8 checkpoint, pass the weight loaders.
+            # If loading an fp16 checkpoint, do not (we will quantize in
+            #   process_weights_after_loading()
+            if quant_config.is_checkpoint_fp8_serialized:
+                set_weight_attrs(self.w13_scale, {
+                    "weight_loader": self.weight_loader,
+                })
+                set_weight_attrs(self.w2_scale, {
+                    "weight_loader": self.weight_loader,
+                })
+
+            # ACT_SCALE (for fp8)
+            if quant_config.activation_scheme == "static":
+                if not quant_config.is_checkpoint_fp8_serialized:
+                    raise ValueError(
+                        "Found static activation scheme for checkpoint that "
+                        "was not serialized fp8.")
+                self.a13_scale = nn.Parameter(torch.zeros(
+                    self.num_total_experts, dtype=torch.float32),
+                                              requires_grad=False)
+                self.a2_scale = nn.Parameter(torch.zeros(
+                    self.num_total_experts, dtype=torch.float32),
+                                             requires_grad=False)
+
+                set_weight_attrs(self.a13_scale, {
+                    "weight_loader": self.weight_loader,
+                })
+                set_weight_attrs(self.a2_scale, {
+                    "weight_loader": self.weight_loader,
+                })
+
+    def weight_loader(self, param: nn.Parameter, loaded_weight: torch.Tensor,
+                      weight_name: str, expert_id: int):
+        tp_rank = get_tensor_model_parallel_rank()
+        param_data = param.data
+        shard_size = self.intermediate_size
+        shard = slice(tp_rank * shard_size, (tp_rank + 1) * shard_size)
+        if weight_name.endswith("w1.weight"):
+            param_data[expert_id, 0:shard_size, :] = loaded_weight[shard, :]
+        if weight_name.endswith("w3.weight"):
+            param_data[expert_id,
+                       shard_size:2 * shard_size, :] = loaded_weight[shard, :]
+        if weight_name.endswith("w2.weight"):
+            param_data[expert_id, :, :] = loaded_weight[:, shard]
+        if "act_scale" in weight_name or "weight_scale" in weight_name:
+            param_data[expert_id] = loaded_weight
+
+    def process_weights_after_loading(self):
+        # Fp8 is the only case where we need to process after loading.
+        if not self.use_fp8:
+            return
+
+        # If checkpoint is fp16, quantize here.
+        if not self.quant_config.is_checkpoint_fp8_serialized:
+            w13_weight = torch.empty_like(self.w13_weight.data,
+                                          dtype=torch.float8_e4m3fn)
+            w2_weight = torch.empty_like(self.w2_weight.data,
+                                         dtype=torch.float8_e4m3fn)
+            for expert in range(self.num_total_experts):
+                w13_weight[expert, :, :], self.w13_scale[
+                    expert] = ops.scaled_fp8_quant(
+                        self.w13_weight.data[expert, :, :])
+                w2_weight[expert, :, :], self.w2_scale[
+                    expert] = ops.scaled_fp8_quant(
+                        self.w2_weight.data[expert, :, :])
+            self.w13_weight = nn.Parameter(w13_weight, requires_grad=False)
+            self.w2_weight = nn.Parameter(w2_weight, requires_grad=False)
+
+        # If checkpoint is fp8 + static, cleanup act_scales.
+        #   Since state_dict has an act_scale per expert but our kernels
+        #   are passed one act_scale shared across all experts.
+        elif self.quant_config.activation_scheme == "static":
+            if self.a13_scale is None or self.a2_scale is None:
+                raise ValueError(
+                    "QuantConfig has static quantization, but found "
+                    "activation scales are None.")
+
+            if (not all_close_1d(self.a13_scale)
+                    or not all_close_1d(self.a2_scale)):
+                print_warning_once(
+                    "Found act_scales that are not equal for fp8 MoE layer. "
+                    "Using the maximum across experts for each layer. ")
+
+            self.a13_scale = nn.Parameter(self.a13_scale.max(),
+                                          requires_grad=False)
+            self.a2_scale = nn.Parameter(self.a2_scale.max(),
+                                         requires_grad=False)
+
+    def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
+        num_tokens, hidden_size = hidden_states.shape
+        hidden_states = hidden_states.view(-1, self.hidden_size)
+        # router_logits: (num_tokens, n_experts)
+        router_logits, _ = self.gate(hidden_states)
+        final_hidden_states = fused_moe(hidden_states,
+                                        self.w13_weight,
+                                        self.w2_weight,
+                                        router_logits,
+                                        self.top_k,
+                                        renormalize=True,
+                                        inplace=True,
+                                        use_fp8=self.use_fp8,
+                                        w1_scale=self.w13_scale,
+                                        w2_scale=self.w2_scale,
+                                        a1_scale=self.a13_scale,
+                                        a2_scale=self.a2_scale)
+
+        if self.tp_size > 1:
+            final_hidden_states = tensor_model_parallel_all_reduce(
+                final_hidden_states)
+
+        return final_hidden_states.view(num_tokens, hidden_size)
+
+
+class MixtralAttention(nn.Module):
+
+    def __init__(self,
+                 hidden_size: int,
+                 num_heads: int,
+                 num_kv_heads: int,
+                 max_position: int = 4096 * 32,
+                 rope_theta: float = 10000,
+                 quant_config: Optional[QuantizationConfig] = None,
+                 sliding_window: Optional[int] = None) -> None:
+        super().__init__()
+        self.hidden_size = hidden_size
+        tp_size = get_tensor_model_parallel_world_size()
+        self.total_num_heads = num_heads
+        assert self.total_num_heads % tp_size == 0
+        self.num_heads = self.total_num_heads // tp_size
+        self.total_num_kv_heads = num_kv_heads
+        if self.total_num_kv_heads >= tp_size:
+            # Number of KV heads is greater than TP size, so we partition
+            # the KV heads across multiple tensor parallel GPUs.
+            assert self.total_num_kv_heads % tp_size == 0
+        else:
+            # Number of KV heads is less than TP size, so we replicate
+            # the KV heads across multiple tensor parallel GPUs.
+            assert tp_size % self.total_num_kv_heads == 0
+        self.num_kv_heads = max(1, self.total_num_kv_heads // tp_size)
+        self.head_dim = hidden_size // self.total_num_heads
+        self.q_size = self.num_heads * self.head_dim
+        self.kv_size = self.num_kv_heads * self.head_dim
+        self.scaling = self.head_dim**-0.5
+        self.rope_theta = rope_theta
+        self.sliding_window = sliding_window
+
+        if isinstance(
+                quant_config,
+                Fp8Config) and not quant_config.is_checkpoint_fp8_serialized:
+            print_warning_once(
+                "For Mixtral FP8 quantization, we currently do not quantize "
+                "the attention layers until their FP8 performance is improved."
+            )
+            quant_config = None
+
+        self.qkv_proj = QKVParallelLinear(
+            hidden_size,
+            self.head_dim,
+            self.total_num_heads,
+            self.total_num_kv_heads,
+            bias=False,
+            quant_config=quant_config,
+        )
+        self.o_proj = RowParallelLinear(
+            self.total_num_heads * self.head_dim,
+            hidden_size,
+            bias=False,
+            quant_config=quant_config,
+        )
+        self.rotary_emb = get_rope(
+            self.head_dim,
+            rotary_dim=self.head_dim,
+            max_position=max_position,
+            base=int(self.rope_theta),
+            is_neox_style=True,
+        )
+        self.attn = Attention(
+            self.num_heads,
+            self.head_dim,
+            self.scaling,
+            num_kv_heads=self.num_kv_heads,
+            sliding_window=self.sliding_window,
+        )
+
+    def forward(
+        self,
+        positions: torch.Tensor,
+        hidden_states: torch.Tensor,
+        kv_cache: torch.Tensor,
+        attn_metadata: AttentionMetadata,
+    ) -> torch.Tensor:
+        qkv, _ = self.qkv_proj(hidden_states)
+        q, k, v = qkv.split([self.q_size, self.kv_size, self.kv_size], dim=-1)
+        q, k = self.rotary_emb(positions, q, k)
+        attn_output = self.attn(q, k, v, kv_cache, attn_metadata)
+        output, _ = self.o_proj(attn_output)
+        return output
+
+
+class MixtralDecoderLayer(nn.Module):
+
+    def __init__(
+        self,
+        config: MixtralConfig,
+        quant_config: Optional[QuantizationConfig] = None,
+    ) -> None:
+        super().__init__()
+        self.hidden_size = config.hidden_size
+        # Requires transformers > 4.32.0
+        rope_theta = getattr(config, "rope_theta", 10000)
+        self.self_attn = MixtralAttention(
+            hidden_size=self.hidden_size,
+            num_heads=config.num_attention_heads,
+            max_position=config.max_position_embeddings,
+            num_kv_heads=config.num_key_value_heads,
+            rope_theta=rope_theta,
+            sliding_window=config.sliding_window,
+            quant_config=quant_config)
+        self.block_sparse_moe = MixtralMoE(
+            num_experts=config.num_local_experts,
+            top_k=config.num_experts_per_tok,
+            hidden_size=config.hidden_size,
+            intermediate_size=config.intermediate_size,
+            quant_config=quant_config)
+        self.input_layernorm = RMSNorm(config.hidden_size,
+                                       eps=config.rms_norm_eps)
+        self.post_attention_layernorm = RMSNorm(config.hidden_size,
+                                                eps=config.rms_norm_eps)
+
+    def forward(
+        self,
+        positions: torch.Tensor,
+        hidden_states: torch.Tensor,
+        kv_cache: torch.Tensor,
+        attn_metadata: AttentionMetadata,
+        residual: Optional[torch.Tensor],
+    ) -> torch.Tensor:
+        # Self Attention
+        if residual is None:
+            residual = hidden_states
+            hidden_states = self.input_layernorm(hidden_states)
+        else:
+            hidden_states, residual = self.input_layernorm(
+                hidden_states, residual)
+        hidden_states = self.self_attn(
+            positions=positions,
+            hidden_states=hidden_states,
+            kv_cache=kv_cache,
+            attn_metadata=attn_metadata,
+        )
+
+        # Fully Connected
+        hidden_states, residual = self.post_attention_layernorm(
+            hidden_states, residual)
+        hidden_states = self.block_sparse_moe(hidden_states)
+        return hidden_states, residual
+
+
+class MixtralModel(nn.Module):
+
+    def __init__(
+        self,
+        config: MixtralConfig,
+        quant_config: Optional[QuantizationConfig] = None,
+        lora_config: Optional[LoRAConfig] = None,
+    ) -> None:
+        super().__init__()
+        self.padding_idx = config.pad_token_id
+        lora_vocab = (lora_config.lora_extra_vocab_size *
+                      (lora_config.max_loras or 1)) if lora_config else 0
+        self.vocab_size = config.vocab_size + lora_vocab
+        self.org_vocab_size = config.vocab_size
+
+        self.embed_tokens = VocabParallelEmbedding(
+            self.vocab_size,
+            config.hidden_size,
+            org_num_embeddings=config.vocab_size,
+        )
+        self.layers = nn.ModuleList([
+            MixtralDecoderLayer(config, quant_config=quant_config)
+            for _ in range(config.num_hidden_layers)
+        ])
+        self.norm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+
+    def forward(
+        self,
+        input_ids: torch.Tensor,
+        positions: torch.Tensor,
+        kv_caches: List[torch.Tensor],
+        attn_metadata: AttentionMetadata,
+    ) -> torch.Tensor:
+        hidden_states = self.embed_tokens(input_ids)
+        residual = None
+        for i in range(len(self.layers)):
+            layer = self.layers[i]
+            hidden_states, residual = layer(positions, hidden_states,
+                                            kv_caches[i], attn_metadata,
+                                            residual)
+        hidden_states, _ = self.norm(hidden_states, residual)
+        return hidden_states
+
+
+class MixtralForCausalLM(nn.Module):
+    fall_back_to_pt_during_load = False
+
+    packed_modules_mapping = {
+        "qkv_proj": [
+            "q_proj",
+            "k_proj",
+            "v_proj",
+        ],
+    }
+
+    # LoRA specific attributes
+    supported_lora_modules = [
+        "qkv_proj",
+        "o_proj",
+        "embed_tokens",
+        "lm_head",
+    ]
+    embedding_modules = {
+        "embed_tokens": "input_embeddings",
+        "lm_head": "output_embeddings",
+    }
+    embedding_padding_modules = ["lm_head"]
+
+    def __init__(
+        self,
+        config: MixtralConfig,
+        quant_config: Optional[QuantizationConfig] = None,
+        lora_config: Optional[LoRAConfig] = None,
+    ) -> None:
+        super().__init__()
+        self.config = config
+        self.model = MixtralModel(config,
+                                  quant_config,
+                                  lora_config=lora_config)
+        self.unpadded_vocab_size = config.vocab_size
+        if lora_config:
+            self.unpadded_vocab_size += lora_config.lora_extra_vocab_size
+        self.lm_head = ParallelLMHead(
+            self.unpadded_vocab_size,
+            config.hidden_size,
+            org_num_embeddings=config.vocab_size,
+            padding_size=DEFAULT_VOCAB_PADDING_SIZE
+            # We need bigger padding if using lora for kernel
+            # compatibility
+            if not lora_config else lora_config.lora_vocab_padding_size,
+        )
+        self.logits_processor = LogitsProcessor(self.unpadded_vocab_size,
+                                                config.vocab_size)
+        self.sampler = Sampler()
+
+    def forward(
+        self,
+        input_ids: torch.Tensor,
+        positions: torch.Tensor,
+        kv_caches: List[torch.Tensor],
+        attn_metadata: AttentionMetadata,
+    ) -> torch.Tensor:
+        hidden_states = self.model(input_ids, positions, kv_caches,
+                                   attn_metadata)
+        return hidden_states
+
+    def compute_logits(self, hidden_states: torch.Tensor,
+                       sampling_metadata: SamplingMetadata) -> torch.Tensor:
+        logits = self.logits_processor(self.lm_head.weight, hidden_states,
+                                       sampling_metadata)
+        return logits
+
+    def sample(
+        self,
+        logits: Optional[torch.Tensor],
+        sampling_metadata: SamplingMetadata,
+    ) -> Optional[SamplerOutput]:
+        next_tokens = self.sampler(logits, sampling_metadata)
+        return next_tokens
+
+    def load_weights(self, weights: Iterable[Tuple[str, torch.Tensor]]):
+        stacked_params_mapping = [
+            # (param_name, shard_name, shard_id)
+            ("qkv_proj", "q_proj", "q"),
+            ("qkv_proj", "k_proj", "k"),
+            ("qkv_proj", "v_proj", "v"),
+        ]
+
+        expert_params_mapping = [
+            # These are the weight scales for the experts
+            # (param_name, weight_name, expert_id)
+            ("w13_scale" if weight_name in ["w1", "w3"] else "w2_scale",
+             f"experts.{expert_id}.{weight_name}.weight_scale", expert_id)
+            for expert_id in range(self.config.num_local_experts)
+            for weight_name in ["w1", "w2", "w3"]
+        ] + [
+            # These are the weights for the experts
+            # (param_name, weight_name, expert_id)
+            ("w13_weight" if weight_name in ["w1", "w3"] else "w2_weight",
+             f"experts.{expert_id}.{weight_name}.weight", expert_id)
+            for expert_id in range(self.config.num_local_experts)
+            for weight_name in ["w1", "w2", "w3"]
+        ] + [
+            # These are the activation scales for the experts
+            # (param_name, weight_name, expert_id)
+            ("a13_scale" if weight_name in ["w1", "w3"] else "a2_scale",
+             f"experts.{expert_id}.{weight_name}.act_scale", expert_id)
+            for expert_id in range(self.config.num_local_experts)
+            for weight_name in ["w1", "w2", "w3"]
+        ]
+
+        params_dict = dict(self.named_parameters())
+        for name, loaded_weight in weights:
+            if "rotary_emb.inv_freq" in name:
+                continue
+
+            for (param_name, weight_name, shard_id) in stacked_params_mapping:
+                if weight_name not in name:
+                    continue
+                name = name.replace(weight_name, param_name)
+                # Skip loading extra bias for GPTQ models.
+                if name.endswith(".bias") and name not in params_dict:
+                    continue
+                param = params_dict[name]
+                weight_loader = param.weight_loader
+                weight_loader(param, loaded_weight, shard_id)
+                break
+            else:
+                for param_name, weight_name, expert_id in expert_params_mapping:
+                    if weight_name not in name:
+                        continue
+                    name = name.replace(weight_name, param_name)
+                    param = params_dict[name]
+                    weight_loader = param.weight_loader
+                    weight_loader(param,
+                                  loaded_weight,
+                                  weight_name,
+                                  expert_id=expert_id)
+                    break
+                else:
+                    # Skip loading extra bias for GPTQ models.
+                    if name.endswith(".bias") and name not in params_dict:
+                        continue
+                    param = params_dict[name]
+                    weight_loader = getattr(param, "weight_loader",
+                                            default_weight_loader)
+                    weight_loader(param, loaded_weight)
+
+
+def all_close_1d(x: torch.Tensor) -> bool:
+    assert len(x.shape) == 1
+    return all(torch.allclose(x[0], x[i]) for i in range(x.shape[0]))