[Benchmark] Support sample from HF datasets and image input for benchmark_serving (#8495)

benchmarks/backend_request_func.py

@@ -25,6 +25,7 @@ class RequestFuncInput:
     best_of: int = 1
     use_beam_search: bool = False
     logprobs: Optional[int] = None
+    multi_modal_content: Optional[dict] = None
 
 
 @dataclass
@@ -312,12 +313,15 @@ async def async_request_openai_chat_completions(
 
     async with aiohttp.ClientSession(timeout=AIOHTTP_TIMEOUT) as session:
         assert not request_func_input.use_beam_search
+        content = [{"type": "text", "text": request_func_input.prompt}]
+        if request_func_input.multi_modal_content:
+            content.append(request_func_input.multi_modal_content)
         payload = {
             "model": request_func_input.model,
             "messages": [
                 {
                     "role": "user",
-                    "content": request_func_input.prompt,
+                    "content": content
                 },
             ],
             "temperature": 0.0,