[Bugfix] SharedStorage Connector for V1 PD multimodal (#21611)

Signed-off-by: fake0fan <645327136@qq.com>
Signed-off-by: herotai214 <herotai214@gmail.com>
Co-authored-by: herotai214 <herotai214@gmail.com>

tests/v1/kv_connector/unit/test_shared_storage_connector.py

+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+from dataclasses import asdict
+from typing import NamedTuple
+
+from PIL import Image
+
+from vllm import LLM, EngineArgs, SamplingParams
+from vllm.assets.image import ImageAsset
+from vllm.config import KVTransferConfig
+from vllm.multimodal.utils import encode_image_base64
+
+MODEL_NAME = "Qwen/Qwen2.5-VL-3B-Instruct"
+
+SAMPLING_PARAMS = SamplingParams(temperature=0.0, top_k=1, max_tokens=128)
+
+TEXT_PROMPTS = [
+    "What's in the image(s)? Around 30 words. What's special in 2nd image?",
+    "The future of AI is",
+]
+
+
+class InputCase(NamedTuple):
+    text: str
+    img: list[Image]
+    expected_len: int
+    info: str
+
+
+def _check_path_len(path):
+    """Return the latest length in path"""
+    return len(list(path.iterdir()))
+
+
+def _list_path(path):
+    """Return the list of foldername (hashes generatd) under the path"""
+    return list(path.iterdir())
+
+
+def run_test(tmp_path, processor, llm: LLM, question: str,
+             image_urls: list[Image], expected_len: int, info: str):
+    """
+    One individual test to process the prompt and output base on 1 set of input
+    Then check if the length in the strorage path matches the expected length
+    `info` introduces details or purpose of the individual test
+    """
+    print(f"***info: {info}***")
+    print(
+        f"**Expected storage path length after llm generate: {expected_len}**")
+    process_prompt(processor, llm, question, image_urls)
+
+    print(f"Path matched expected length: {_check_path_len(tmp_path)}")
+    print(f"Hashes under the storage path: {_list_path(tmp_path)}")
+
+    assert _check_path_len(tmp_path) == expected_len, (
+        f"Expect storage path length {expected_len} ;",
+        f"but end up {_check_path_len(tmp_path)} instead. ", f"Info: {info}")
+
+
+def process_prompt(processor, llm: LLM, question: str,
+                   image_urls: list[Image]):
+    """
+    Form the prompt based on the text and image input, then llm generate output
+    """
+    placeholders = [{
+        "type": "image_url",
+        "image_url": {
+            "url": f"data:image;base64,{encode_image_base64(image_pil)}"
+        }
+    } for image_pil in image_urls]
+
+    messages = [
+        {
+            "role": "system",
+            "content": "You are a helpful assistant."
+        },
+        {
+            "role": "user",
+            "content": [
+                *placeholders,
+                {
+                    "type": "text",
+                    "text": question
+                },
+            ],
+        },
+    ]
+
+    prompt = processor.apply_chat_template(messages,
+                                           tokenize=False,
+                                           add_generation_prompt=True)
+
+    outputs = llm.generate(
+        {
+            "prompt":
+            prompt,
+            **({
+                "multi_modal_data": {
+                    "image": [*image_urls]
+                }
+            } if image_urls else {})
+        },
+        sampling_params=SAMPLING_PARAMS,
+    )
+
+    print("-" * 50)
+    print("Output:")
+    for o in outputs:
+        generated_text = o.outputs[0].text
+        print(generated_text)
+        print("-" * 50)
+
+
+def test_shared_storage_connector_hashes(tmp_path):
+    """
+    Tests that SharedStorageConnector saves KV to the storage locations
+    with proper hashes; that are unique for inputs with identical text but 
+    differnt images (same size), or same multiple images but different orders.
+    """
+    # Using tmp_path as the storage path to store KV
+    print(f"KV storage path at: {str(tmp_path)}")
+
+    # Configure the SharedStorageConnector
+    kv_transfer_config = KVTransferConfig(
+        kv_connector="SharedStorageConnector",
+        kv_role="kv_both",
+        kv_connector_extra_config={"shared_storage_path": str(tmp_path)})
+
+    engine_args = EngineArgs(
+        model=MODEL_NAME,
+        max_model_len=8192,
+        max_num_seqs=1,
+        kv_transfer_config=kv_transfer_config,
+        limit_mm_per_prompt={"image": 2},
+    )
+
+    # don't put this import at the top level
+    # it will call torch.cuda.device_count()
+    from transformers import AutoProcessor  # noqa: F401
+
+    # Create processor to handle the chat prompt
+    processor = AutoProcessor.from_pretrained(MODEL_NAME)
+
+    # Prepare images for the tests
+    # Resize to the same size to check hashes correctness
+    image_1 = ImageAsset("stop_sign").pil_image.resize((1280, 720))
+    image_2 = ImageAsset("cherry_blossom").pil_image.resize((1280, 720))
+
+    # Make sure that they are not the same picture
+    assert image_1 != image_2, "The images should not be identical"
+
+    # Create the LLM instance
+    engine_args = asdict(engine_args)
+    llm = LLM(**engine_args)
+
+    # Prepare the input cases
+    input_cases = [
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[image_1],
+                  expected_len=1,
+                  info="image_1 single input the first time."),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[image_2],
+                  expected_len=2,
+                  info=("image_2 single input the first time. "
+                        "It is in same pixel size with image_1, yet it "
+                        "should be able to form a new unique hash.")),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[image_1],
+                  expected_len=2,
+                  info=("image_1 single input the 2nd time. "
+                        "It should not form aother new hash.")),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[image_2],
+                  expected_len=2,
+                  info=("image_2 single input the 2nd time. "
+                        "It should not form aother new hash.")),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[image_1, image_2],
+                  expected_len=3,
+                  info="image_1 with image_2 input the first time."),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[image_2, image_1],
+                  expected_len=4,
+                  info="The image order is swapped. Should form new hash."),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[image_1, image_2],
+                  expected_len=4,
+                  info=("[image_1, image_2] input the 2nd time. "
+                        "It should not form aother new hash.")),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[image_2, image_1],
+                  expected_len=4,
+                  info=("[image_2, image_1] input the 2nd time. "
+                        "It should not form aother new hash.")),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[],
+                  expected_len=5,
+                  info="Pure text input test as a case-control"),
+        InputCase(text=TEXT_PROMPTS[0],
+                  img=[],
+                  expected_len=5,
+                  info="Identical pure text input as a case-control"),
+        InputCase(text=TEXT_PROMPTS[1],
+                  img=[],
+                  expected_len=6,
+                  info="Another pure text input as a case-control"),
+    ]
+
+    # Run tests
+    for case_id, (text, img, expected_len, info) in enumerate(input_cases):
+        print("\n", "=" * 25, f"Below running input case: {case_id}", "=" * 25)
+        run_test(tmp_path, processor, llm, text, img, expected_len, info)
+
+    print("All tests passed successfully!")

vllm/distributed/kv_transfer/kv_connector/v1/shared_storage_connector.py

@@ -32,10 +32,11 @@ class ReqMeta:
     slot_mapping: torch.Tensor
     # Is store or load
     is_store: bool
+    mm_hashes: list[str]
 
     @staticmethod
     def make_meta(token_ids: list[int], block_ids: list[int], block_size: int,
-                  is_store: bool) -> "ReqMeta":
+                  is_store: bool, mm_hashes: list[str]) -> "ReqMeta":
         valid_num_tokens = align_to_block_size(len(token_ids), block_size)
         token_ids_tensor = torch.tensor(token_ids)[:valid_num_tokens]
         block_ids_tensor = torch.tensor(block_ids)
@@ -48,6 +49,7 @@ class ReqMeta:
             token_ids=token_ids_tensor,
             slot_mapping=slot_mapping,
             is_store=is_store,
+            mm_hashes=mm_hashes,
         )
 
 
@@ -64,9 +66,11 @@ class SharedStorageConnectorMetadata(KVConnectorMetadata):
         block_ids: list[int],
         block_size: int,
         is_store: bool,
+        mm_hashes: list[str],
     ) -> None:
         self.requests.append(
-            ReqMeta.make_meta(token_ids, block_ids, block_size, is_store))
+            ReqMeta.make_meta(token_ids, block_ids, block_size, is_store,
+                              mm_hashes))
 
 
 class SharedStorageConnector(KVConnectorBase_V1):
@@ -169,7 +173,7 @@ class SharedStorageConnector(KVConnectorBase_V1):
                         forward_context.virtual_engine]
 
                 filename = self._generate_filename_debug(
-                    layer_name, request.token_ids)
+                    layer_name, request.token_ids, request.mm_hashes)
                 kv_cache = safetensors.torch.load_file(
                     filename)["kv_cache"].cuda()
                 inject_kv_into_layer(kv_cache_layer, kv_cache,
@@ -221,7 +225,7 @@ class SharedStorageConnector(KVConnectorBase_V1):
         for request in connector_metadata.requests:
             if request.is_store:
                 filename = self._generate_filename_debug(
-                    layer_name, request.token_ids)
+                    layer_name, request.token_ids, request.mm_hashes)
                 kv_cache = extract_kv_from_layer(kv_layer,
                                                  request.slot_mapping)
                 tensors = {"kv_cache": kv_cache.detach().cpu()}
@@ -299,7 +303,8 @@ class SharedStorageConnector(KVConnectorBase_V1):
                 meta.add_request(token_ids=new_req.prompt_token_ids,
                                  block_ids=new_req.block_ids[0],
                                  block_size=self._block_size,
-                                 is_store=False)
+                                 is_store=False,
+                                 mm_hashes=new_req.mm_hashes)
                 total_need_load += 1
             else:
                 # NOTE: here, we set the store and load being exclusive,
@@ -310,7 +315,8 @@ class SharedStorageConnector(KVConnectorBase_V1):
                     meta.add_request(token_ids=new_req.prompt_token_ids,
                                      block_ids=new_req.block_ids[0],
                                      block_size=self._block_size,
-                                     is_store=True)
+                                     is_store=True,
+                                     mm_hashes=new_req.mm_hashes)
 
         cached_reqs = scheduler_output.scheduled_cached_reqs
         for i, req_id in enumerate(cached_reqs.req_ids):
@@ -338,7 +344,8 @@ class SharedStorageConnector(KVConnectorBase_V1):
                 meta.add_request(token_ids=token_ids,
                                  block_ids=block_ids,
                                  block_size=self._block_size,
-                                 is_store=False)
+                                 is_store=False,
+                                 mm_hashes=request.mm_hashes)
                 total_need_load += 1
 
         assert total_need_load == len(self._requests_need_load)
@@ -359,20 +366,28 @@ class SharedStorageConnector(KVConnectorBase_V1):
             len(request.prompt_token_ids) - 1, self._block_size)
         foldername = self._generate_foldername_debug(torch.tensor(
             request.prompt_token_ids)[:num_tokens_to_check],
+                                                     request.mm_hashes,
                                                      create_folder=False)
         return os.path.exists(foldername)
 
     def _generate_foldername_debug(
         self,
-        input_ids: torch.Tensor,
+        token_ids: torch.Tensor,
+        mm_hashes: list[str],
         create_folder=False,
     ) -> str:
         """Generate a folder name based on the hash of the bytes of the input 
         ids.
         """
-        input_ids_bytes = input_ids.numpy().tobytes()
-        input_ids_hash = hashlib.md5(input_ids_bytes,
+        token_bytes = token_ids.numpy().tobytes()
+        # Add mm_hashes to the bytes being hashed to avoid path traversal and
+        # to create a canonical key.
+        if mm_hashes:
+            mm_str = "-".join(mm_hashes)
+            token_bytes += mm_str.encode('utf-8')
+        input_ids_hash = hashlib.md5(token_bytes,
                                      usedforsecurity=False).hexdigest()
+
         foldername = os.path.join(self._storage_path, input_ids_hash)
         if create_folder:
             os.makedirs(foldername, exist_ok=True)
@@ -381,12 +396,14 @@ class SharedStorageConnector(KVConnectorBase_V1):
     def _generate_filename_debug(
         self,
         layer_name: str,
-        input_ids: torch.Tensor,
+        token_ids: torch.Tensor,
+        mm_hashes: list[str],
     ) -> str:
         """Generate a file name based on the layer name and the hash 
         of the bytes of the input ids.
         """
-        foldername = self._generate_foldername_debug(input_ids,
+        foldername = self._generate_foldername_debug(token_ids,
+                                                     mm_hashes=mm_hashes,
                                                      create_folder=True)
         return os.path.join(foldername, f"{layer_name}.safetensors")