[PyTorch] Fix AttentionParams comparison logic (#1397)

only compare the recipe in AttentionParams.fp8_meta
Signed-off-by: Charlene Yang <8636796+cyanguwa@users.noreply.github.com>

transformer_engine/pytorch/attention.py

@@ -303,6 +303,24 @@ class AttentionParams:
     fp8: bool = False
     fp8_meta: Union[Dict[str, Any], None] = None
 
+    def __eq__(self, other):
+        """
+        Overwrite dataclass.__eq__ so that only fp8_meta["recipe"] is compared,
+        since all other entries of fp8_meta are unused in get_attention_backend.
+        """
+        if not isinstance(other, self.__class__):
+            return NotImplemented
+        for field in fields(self):
+            fname = field.name
+            sf = getattr(self, fname)
+            of = getattr(other, fname)
+            if fname != "fp8_meta":
+                if sf != of:
+                    return False
+            elif sf["recipe"] != of["recipe"]:
+                return False
+        return True
+
 
 _alibi_cache = {
     "_num_heads": None,