[Bugfix] Fix mm_limits access for merged multi-modal processor (#12252)

Signed-off-by: DarkLight1337 <tlleungac@connect.ust.hk>

vllm/multimodal/profiling.py

@@ -106,7 +106,7 @@ class MultiModalProfiler(Generic[_I]):
     def dummy_inputs(self) -> BaseDummyInputsBuilder[_I]:
         return self.processor.dummy_inputs
 
-    def _get_mm_limits(self) -> Mapping[str, int]:
+    def get_mm_limits(self) -> Mapping[str, int]:
         mm_config = self.processing_info.ctx.get_mm_config()
         mm_limit_per_prompt = mm_config.limit_per_prompt
 
@@ -146,7 +146,7 @@ class MultiModalProfiler(Generic[_I]):
         # Avoid circular import
         from vllm.sequence import SequenceData
 
-        mm_counts = self._get_mm_limits()
+        mm_counts = self.get_mm_limits()
 
         info = self.processing_info
         mm_max_tokens_per_item = info.get_mm_max_tokens_per_item(seq_len)

vllm/multimodal/registry.py

@@ -17,7 +17,7 @@ from .image import ImagePlugin
 from .inputs import MultiModalDataDict, MultiModalKwargs, NestedTensors
 from .processing import (BaseMultiModalProcessor, BaseProcessingInfo,
                          ProcessingCache)
-from .profiling import BaseDummyInputsBuilder
+from .profiling import BaseDummyInputsBuilder, MultiModalProfiler
 from .utils import cached_get_tokenizer
 from .video import VideoPlugin
 
@@ -282,13 +282,13 @@ class MultiModalRegistry:
             This is currently directly used only in V1 for profiling the memory 
             usage of a model.
         """
-        limits_per_plugin = self._limits_by_model[model_config]
+        mm_limits = self.get_mm_limits_per_prompt(model_config)
 
         return {
             key: max_tokens_per_mm_item
             for key, max_tokens_per_mm_item in
             self.get_max_tokens_per_item_by_modality(model_config).items()
-            if limits_per_plugin[key] > 0
+            if mm_limits[key] > 0
         }
 
     def get_max_tokens_by_modality(
@@ -304,10 +304,10 @@ class MultiModalRegistry:
         Note:
             This should be called after :meth:`init_mm_limits_per_prompt`.
         """
-        limits_per_plugin = self._limits_by_model[model_config]
+        mm_limits = self.get_mm_limits_per_prompt(model_config)
 
         return {
-            key: limits_per_plugin[key] * max_tokens_per_mm_item
+            key: mm_limits[key] * max_tokens_per_mm_item
             for key, max_tokens_per_mm_item in
             self.get_max_tokens_per_item_by_modality(model_config).items()
         }
@@ -371,6 +371,15 @@ class MultiModalRegistry:
         Note:
             This should be called after :meth:`init_mm_limits_per_prompt`.
         """
+        if self.has_processor(model_config):
+            tokenizer = cached_get_tokenizer(
+                model_config.tokenizer,
+                trust_remote_code=model_config.trust_remote_code,
+            )
+            processor = self.create_processor(model_config, tokenizer)
+            profiler = MultiModalProfiler(processor)
+            return profiler.get_mm_limits()
+
         return self._limits_by_model[model_config]
 
     def register_processor(