[Neuron] Add Multi-Modal model support for Neuron (#18921)

Signed-off-by: Satyajith Chilappagari <satchill@amazon.com>
Co-authored-by: Ashraf Mahgoub <ashymahg@amazon.com>
Co-authored-by: Rohith Nallamaddi <nalrohit@amazon.com>
Co-authored-by: FeliciaLuo <luof@amazon.com>
Co-authored-by: Elaine Zhao <elaineyz@amazon.com>

examples/offline_inference/neuron_multimodal.py

+# SPDX-License-Identifier: Apache-2.0
+import requests
+import torch
+from neuronx_distributed_inference.models.mllama.utils import add_instruct
+from PIL import Image
+
+from vllm import LLM, SamplingParams, TextPrompt
+
+
+def get_image(image_url):
+    image = Image.open(requests.get(image_url, stream=True).raw)
+    return image
+
+
+# Model Inputs
+PROMPTS = [
+    "What is in this image? Tell me a story",
+    "What is the recipe of mayonnaise in two sentences?",
+    "Describe this image",
+    "What is the capital of Italy famous for?",
+]
+IMAGES = [
+    get_image(
+        "https://images.pexels.com/photos/1108099/pexels-photo-1108099.jpeg?auto=compress&cs=tinysrgb&dpr=1&w=500"
+    ),
+    None,
+    get_image(
+        "https://images.pexels.com/photos/1108099/pexels-photo-1108099.jpeg?auto=compress&cs=tinysrgb&dpr=1&w=500"
+    ),
+    None,
+]
+SAMPLING_PARAMS = [
+    dict(top_k=1, temperature=1.0, top_p=1.0, max_tokens=16)
+    for _ in range(len(PROMPTS))
+]
+
+
+def get_VLLM_mllama_model_inputs(prompt, single_image, sampling_params):
+    # Prepare all inputs for mllama generation, including:
+    # 1. put text prompt into instruct chat template
+    # 2. compose single text and single image prompt into Vllm's prompt class
+    # 3. prepare sampling parameters
+    input_image = single_image
+    has_image = torch.tensor([1])
+    if isinstance(single_image, torch.Tensor) and single_image.numel() == 0:
+        has_image = torch.tensor([0])
+
+    instruct_prompt = add_instruct(prompt, has_image)
+    inputs = TextPrompt(prompt=instruct_prompt)
+
+    if input_image is not None:
+        inputs["multi_modal_data"] = {"image": input_image}
+
+    sampling_params = SamplingParams(**sampling_params)
+    return inputs, sampling_params
+
+
+def print_outputs(outputs):
+    # Print the outputs.
+    for output in outputs:
+        prompt = output.prompt
+        generated_text = output.outputs[0].text
+        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")
+
+
+if __name__ == "__main__":
+    assert (
+        len(PROMPTS) == len(IMAGES) == len(SAMPLING_PARAMS)
+    ), f"""Text, image prompts and sampling parameters should have the 
+            same batch size; but got {len(PROMPTS)}, {len(IMAGES)}, 
+            and {len(SAMPLING_PARAMS)}"""
+
+    # Create an LLM.
+    llm = LLM(
+        model="meta-llama/Llama-3.2-11B-Vision-Instruct",
+        max_num_seqs=1,
+        max_model_len=4096,
+        block_size=4096,
+        device="neuron",
+        tensor_parallel_size=32,
+        override_neuron_config={
+            "sequence_parallel_enabled": False,
+            "skip_warmup": True,
+            "save_sharded_checkpoint": True,
+            "on_device_sampling_config": {
+                "global_topk": 1,
+                "dynamic": False,
+                "deterministic": False,
+            },
+        },
+    )
+
+    batched_inputs = []
+    batched_sample_params = []
+    for pmpt, img, params in zip(PROMPTS, IMAGES, SAMPLING_PARAMS):
+        inputs, sampling_params = get_VLLM_mllama_model_inputs(pmpt, img, params)
+        # test batch-size = 1
+        outputs = llm.generate(inputs, sampling_params)
+        print_outputs(outputs)
+        batched_inputs.append(inputs)
+        batched_sample_params.append(sampling_params)
+
+    # test batch-size = 4
+    outputs = llm.generate(batched_inputs, batched_sample_params)
+    print_outputs(outputs)

vllm/config.py

@@ -1360,6 +1360,16 @@ class ModelConfig:
     @property
     def is_encoder_decoder(self) -> bool:
         """Extract the HF encoder/decoder model flag."""
+        """
+        For Mllama, VLLM overrides HF's is_encoder_decoder flag and sets it to 
+        True to enable cross-attention
+        Neuron needs all multimodal data to be in the decoder and does not 
+        need to explicitly enable cross-attention
+        """
+        if (current_platform.is_neuron()
+                and self.hf_config.model_type == "mllama"):
+            return False
+
         return is_encoder_decoder(self.hf_config)
 
     @property

vllm/model_executor/model_loader/neuronx_distributed.py

@@ -204,6 +204,11 @@ class NeuronMllamaForCausalLM(nn.Module):
                  config: PretrainedConfig,
                  on_device_sampling_disabled: bool = False) -> None:
         super().__init__()
+        # has_image is the only multimodal input that is used in
+        # token-generation
+        # This is a cache (on CPU) that saves has_image data per sequence id
+        # The number of entries in this cache is <= Batch-Size
+        self.has_image_cache: dict[int, torch.Tensor] = {}
         self.config = config
         self.logits_processor = LogitsProcessor(
             config.get_text_config().vocab_size, logits_as_input=True)
@@ -215,11 +220,57 @@ class NeuronMllamaForCausalLM(nn.Module):
 
         # Lazy initialized
         self.model: nn.Module
+        self.is_reorder_needed: bool = True
+
+    def read_from_has_image_cache(self, seq_ids: torch.Tensor):
+        has_image_list = []
+        for index in range(len(seq_ids)):
+            seq_id = seq_ids[index].item()
+            if seq_id in self.has_image_cache:
+                has_image_list.append(self.has_image_cache[seq_id])
+            else:
+                has_image_list.append(torch.tensor([0]))
+        return torch.tensor(has_image_list)
+
+    def write_to_has_image_cache(self, seq_ids: torch.Tensor,
+                                 has_image: torch.Tensor):
+        for index in range(len(seq_ids)):
+            seq_id = seq_ids[index].item()
+            if index < len(has_image):
+                self.has_image_cache[seq_id] = has_image[index]
+            else:
+                self.has_image_cache[seq_id] = torch.zeros(1)
 
     def forward(self, input_ids: torch.Tensor, positions: torch.Tensor,
                 seq_ids: torch.Tensor, pixel_values: torch.Tensor,
                 aspect_ratios: torch.Tensor, num_chunks: torch.Tensor,
                 has_image: torch.Tensor, sampling_params) -> torch.Tensor:
+
+        # We update the has_image cache during prefill
+        # and read the has_image cache during decode
+        if input_ids.shape[-1] > 1:  # prefill
+            self.write_to_has_image_cache(seq_ids, has_image)
+        else:
+            has_image = self.read_from_has_image_cache(seq_ids)
+            bs = input_ids.shape[0]
+            num_chunks = torch.zeros((bs, 1))
+            aspect_ratios = torch.zeros((bs, 1, 2))
+
+        input_block_ids = seq_ids
+        origin_input_block_ids = seq_ids
+        if self.is_reorder_needed:
+            # sort block ids sequentially for perf/neuron support reasons
+            input_block_ids, sorted_indices = torch.sort(input_block_ids)
+            input_ids = torch.index_select(input_ids, 0, sorted_indices)
+            positions = torch.index_select(positions, 0, sorted_indices)
+            sampling_params = torch.index_select(sampling_params, 0,
+                                                 sorted_indices)
+            pixel_values = torch.index_select(pixel_values, 0, sorted_indices)
+            aspect_ratios = torch.index_select(aspect_ratios, 0,
+                                               sorted_indices)
+            num_chunks = torch.index_select(num_chunks, 0, sorted_indices)
+            has_image = torch.index_select(has_image, 0, sorted_indices)
+
         self.vision_mask = create_vision_mask(input_ids, self.vision_token_id)
         output = self.model(
             input_ids.to(torch.int32),
@@ -235,8 +286,14 @@ class NeuronMllamaForCausalLM(nn.Module):
             has_image=has_image.to(torch.int32),
         )
         if self.config.neuron_config.on_device_sampling_config:
-            return output.hidden_states
-        return output.logits[:, -1, :]
+            output = output.hidden_states
+        else:
+            output = output.logits[:, -1, :]
+
+        if self.is_reorder_needed and origin_input_block_ids.shape[0] != 1:
+            restored_indices = torch.argsort(sorted_indices)
+            output = torch.index_select(output, 0, restored_indices)
+        return output
 
     def compute_logits(self, hidden_states: torch.Tensor,
                        sampling_metadata: SamplingMetadata) -> torch.Tensor:
@@ -299,7 +356,7 @@ class NeuronMllamaForCausalLM(nn.Module):
             self.model = neuronx_model_cls(compiled_model_path)
             tokenizer = AutoTokenizer.from_pretrained(model_name_or_path)
             self.vision_token_id = tokenizer(
-                "<|image|>", add_special_tokens=False).input_ids
+                "<|image|>", add_special_tokens=False).input_ids[0]
             self.model.load(compiled_model_path)
             return
         except (FileNotFoundError, ValueError):
@@ -326,7 +383,7 @@ class NeuronMllamaForCausalLM(nn.Module):
 
         # Read "<|image|>" token_id from the tokenizer
         self.vision_token_id = tokenizer("<|image|>",
-                                         add_special_tokens=False).input_ids
+                                         add_special_tokens=False).input_ids[0]
         logger.info("\nLoading model from compiled checkpoint...")
         self.model.load(compiled_model_path)
 

vllm/worker/neuron_model_runner.py

@@ -169,6 +169,7 @@ class NeuronModelRunner(ModelRunnerBase[ModelInputForNeuron]):
 
             mm_kwargs = seq_group_metadata.multi_modal_data
             if mm_kwargs:
+                mm_kwargs = self.process_multi_modal_data_neuron(mm_kwargs)
                 multi_modal_kwargs_list.append(mm_kwargs)
 
         max_seq_len = max(seq_lens)
@@ -274,6 +275,14 @@ class NeuronModelRunner(ModelRunnerBase[ModelInputForNeuron]):
                 sampling_params.top_p = top_p
                 sampling_params.temperature = temperature
 
+        # we need multi_modal_data for later tokens as well
+        multi_modal_kwargs_list: List[MultiModalKwargs] = []
+        for seq_group_metadata in seq_group_metadata_list:
+            mm_data = seq_group_metadata.multi_modal_data
+            if mm_data:
+                multi_modal_kwargs_list.append(mm_data)
+        multi_modal_kwargs = MultiModalKwargs.batch(multi_modal_kwargs_list)
+
         sampling_metadata = SamplingMetadata.prepare(
             seq_group_metadata_list,
             seq_lens,
@@ -422,6 +431,10 @@ class NeuronModelRunner(ModelRunnerBase[ModelInputForNeuron]):
     def vocab_size(self) -> int:
         return self.model_config.get_vocab_size()
 
+    def process_multi_modal_data_neuron(self, mm_data):
+        # this is a no-op for NeuronModelRunner
+        return mm_data
+
     def remove_all_loras(self):
         raise NotImplementedError(
             "LoRAs are not supported for Transformers NeuronX framework")

vllm/worker/neuronx_distributed_model_runner.py

@@ -3,6 +3,8 @@
 from typing import List, Optional, Set
 
 import torch
+from neuronx_distributed_inference.models.mllama.aspect_ratio_utils import (
+    get_all_supported_aspect_ratios)
 from neuronx_distributed_inference.modules.generation.sampling import (
     prepare_sampling_params)
 from neuronx_distributed_inference.modules.lora_serving import (
@@ -17,7 +19,7 @@ from vllm.model_executor import SamplingMetadata
 from vllm.model_executor.layers.sampler import SamplerOutput
 from vllm.model_executor.model_loader.neuronx_distributed import (
     _get_model_architecture, get_neuron_model)
-from vllm.platforms import current_platform
+from vllm.multimodal import MultiModalKwargs
 from vllm.sequence import IntermediateTensors, SequenceGroupMetadata
 from vllm.worker.neuron_model_runner import (ModelInputForNeuron,
                                              NeuronModelRunner)
@@ -121,42 +123,28 @@ class NeuronxDistributedModelRunner(NeuronModelRunner):
         sampling_params = self.get_nxd_sampling_params(
             model_input.sampling_metadata)
 
-        if model_input.multi_modal_kwargs.get('image') is not None:
-            pixel_values = []
-            aspect_ratios = []
-            num_chunks = []
-            has_image = []
-            for multi_modal_input in model_input.multi_modal_kwargs.get(
-                    'image'):
-                image_tensors = self.get_multi_modal_data_neuron(
-                    multi_modal_input.squeeze(0))
-                pixel_values.append(image_tensors[0])
-                aspect_ratios.append(image_tensors[1])
-                num_chunks.append(image_tensors[2])
-                has_image.append(image_tensors[3])
-
-            pixel_values = torch.cat(pixel_values, dim=0)
-            aspect_ratios = torch.cat(aspect_ratios, dim=0)
-            num_chunks = torch.cat(num_chunks, dim=0)
-            has_image = torch.cat(has_image, dim=0)
-
+        if model_input.multi_modal_kwargs.get('pixel_values') is not None:
             hidden_states = self.model(
                 input_ids=model_input.input_tokens,
                 positions=model_input.input_positions,
                 seq_ids=model_input.input_block_ids,
-                pixel_values=pixel_values,
-                aspect_ratios=aspect_ratios,
+                pixel_values=model_input.multi_modal_kwargs.get(
+                    'pixel_values'),
+                aspect_ratios=model_input.multi_modal_kwargs.get(
+                    'aspect_ratios'),
                 sampling_params=sampling_params,
-                num_chunks=num_chunks,
-                has_image=has_image,
+                num_chunks=model_input.multi_modal_kwargs.get('num_chunks'),
+                has_image=model_input.multi_modal_kwargs.get(
+                    'has_image').squeeze(1),
             )
         else:
-            empty_pixel_values = torch.zeros([1, 1, 4, 3, 560, 560],
+            bs = model_input.input_tokens.shape[0] if (model_input.input_tokens
+                                                       is not None) else 1
+            empty_pixel_values = torch.zeros([bs, 1, 4, 3, 560, 560],
                                              dtype=torch.bfloat16)
-            empty_aspect_ratios = torch.ones([1, 1, 2], dtype=torch.int64)
-            num_chunks = torch.tensor([[1]
-                                       ])  # dummy num_chunks, will not be used
-            has_image = torch.tensor([0])
+            empty_aspect_ratios = torch.ones([bs, 1, 2], dtype=torch.int64)
+            num_chunks = torch.zeros((bs, 1), dtype=torch.int32)
+            has_image = torch.zeros([bs], dtype=torch.int32)
             hidden_states = self.model(
                 input_ids=model_input.input_tokens,
                 positions=model_input.input_positions,
@@ -175,6 +163,27 @@ class NeuronxDistributedModelRunner(NeuronModelRunner):
 
         return [output]
 
+    def process_multi_modal_data_neuron(self, mm_data):
+        # Neuron uses aspect_ratios instead of aspect_ratio_ids
+        all_supported_aspect_ratios = get_all_supported_aspect_ratios(
+            self.model.config.vision_config.max_num_tiles)
+        aspect_ratio_ids = mm_data.get("aspect_ratio_ids")
+        mm_data["aspect_ratios"] = torch.tensor(
+            all_supported_aspect_ratios[aspect_ratio_ids]).unsqueeze(0)
+
+        # Neuron's num_chunks is HF's num_tiles
+        mm_data["num_chunks"] = mm_data.get("num_tiles")
+
+        # Input has an image if it has pixel_values
+        bs = mm_data["num_chunks"].shape[0]
+        pixel_values = mm_data.get("pixel_values")
+        if pixel_values is not None and not torch.all(pixel_values == 0):
+            mm_data["has_image"] = torch.ones(bs)
+
+        else:
+            mm_data["has_image"] = torch.zeros(bs)
+        return mm_data
+
     def _get_lora_adapter_ids(self, seq_group_metadata_list):
         # set LoRA adapter IDs for multi-lora serving
         batch_size = len(seq_group_metadata_list)
@@ -200,7 +209,6 @@ class NeuronxDistributedModelRunner(NeuronModelRunner):
         virtual_engine: int = 0,
         finished_requests_ids: Optional[List[str]] = None
     ) -> ModelInputForNeuron:
-        multi_modal_kwargs = None
         # NOTE: We assume that all sequences in the group are all prompts or
         # all decodes.
         is_prompt = seq_group_metadata_list[0].is_prompt
@@ -223,6 +231,14 @@ class NeuronxDistributedModelRunner(NeuronModelRunner):
                 sampling_params.top_p = top_p
                 sampling_params.temperature = temperature
 
+        # we need multi_modal_data for later tokens as well
+        multi_modal_kwargs_list: List[MultiModalKwargs] = []
+        for seq_group_metadata in seq_group_metadata_list:
+            mm_data = seq_group_metadata.multi_modal_data
+            if mm_data:
+                multi_modal_kwargs_list.append(mm_data)
+        multi_modal_kwargs = MultiModalKwargs.batch(multi_modal_kwargs_list)
+
         lora_adapter_ids = self._get_lora_adapter_ids(seq_group_metadata_list)
 
         sampling_metadata = SamplingMetadata.prepare(
@@ -236,18 +252,6 @@ class NeuronxDistributedModelRunner(NeuronModelRunner):
             self.pin_memory,
             generators=self.get_generators(finished_requests_ids))
 
-        if current_platform.use_transformers_neuronx(
-        ) and not self._on_device_sampling_disabled:
-            # Once the request IDs are changed in current iteration, we will
-            # update the on-device sampling parameters.
-            current_batch_request_ids = [
-                seq_group_meta_data.request_id
-                for seq_group_meta_data in seq_group_metadata_list
-            ]
-            if current_batch_request_ids != self._previous_batch_request_ids:
-                self._update_neuron_sampling_params(seq_group_metadata_list)
-                self._previous_batch_request_ids = current_batch_request_ids
-
         return ModelInputForNeuron(input_tokens=input_tokens,
                                    input_positions=input_positions,
                                    input_block_ids=input_block_ids,