Update sparsity_config.py

Author: dbogunowicz

src/sparseml/transformers/compression/sparsity_config.py

@@ -21,6 +21,10 @@
 from compressed_tensors import CompressionFormat, SparsityCompressionConfig
 from compressed_tensors.quantization.utils import is_model_quantized
 from sparseml.pytorch.utils import ModuleSparsificationInfo
+from sparseml.transformers.compression.helpers import (
+    infer_sparsity_structure_from_model,
+    infer_sparsity_structure_from_stage_modifiers,
+)
 
 
 class SparsityConfigMetadata:
@@ -47,26 +51,34 @@ def infer_global_sparsity(
         return global_sparsity
 
     @staticmethod
-    def infer_sparsity_structure() -> str:
+    def infer_sparsity_structure(model: Optional[Module] = None) -> str:
         """
-        Determines what sparsity structure, if any, was applied in the currently active
-        sparse session
+        Determines what sparsity structure, if any, was applied.
+
+        First, there is an attempt to dedue the sparsity structure
+        from the currently active sparse session.
+
+        If that fails, the sparsity structure is inferred from the
+        model (if provided)
+
+        Finally, if both fail, the sparsity structure is set to
+        "unstructured"
 
         :return: sparsity structure as a string
         """
+        sparsity_structure = None
+
         current_session = sparseml.active_session()
         stage_modifiers = current_session.lifecycle.modifiers
-        sparsity_structure = "unstructured"
+        if stage_modifiers:
+            sparsity_structure = infer_sparsity_structure_from_stage_modifiers(
+                stage_modifiers
+            )
 
-        # check for applied pruning modifiers
-        for stage in stage_modifiers:
-            if stage.applied:
-                for modifier in stage.modifiers:
-                    if hasattr(modifier, "mask_structure"):
-                        sparsity_structure = modifier.mask_structure
-                        break
+        if model and sparsity_structure is None:
+            sparsity_structure = infer_sparsity_structure_from_model(model)
 
-        return sparsity_structure
+        return sparsity_structure or "unstructured"
 
     @staticmethod
     def from_pretrained(
@@ -91,7 +103,9 @@ def from_pretrained(
         if global_sparsity < 0.05:
             return None
 
-        sparsity_structure = SparsityConfigMetadata.infer_sparsity_structure()
+        sparsity_structure = SparsityConfigMetadata.infer_sparsity_structure(
+            model=model
+        )
         if is_model_quantized(model):
             # compressing a sparse quantized model is not supported yet
             format = CompressionFormat.dense.value