add logging message for using GPU

Summary: added a logger message when GPU is successfully used with the model and generator included.

Differential Revision: D65907247

aepsych/strategy.py

@@ -164,12 +164,13 @@ def __init__(
             if use_gpu_modeling:
                 if not torch.cuda.is_available():
                     warnings.warn(
-                        "GPU requested for model {type(model).__name__}, but no GPU found! Using CPU instead.",
+                        f"GPU requested for model {type(model).__name__}, but no GPU found! Using CPU instead.",
                         UserWarning,
                     )
                     self.model_device = torch.device("cpu")
                 else:
                     self.model_device = torch.device("cuda")
+                    logger.info(f"Using GPU for modeling with {type(model).__name__}")
             else:
                 self.model_device = torch.device("cpu")
 
@@ -195,6 +196,9 @@ def __init__(
                     self.generator_device = torch.device("cpu")
                 else:
                     self.generator_device = torch.device("cuda")
+                    logger.info(
+                        f"Using GPU for generating with {type(generator).__name__}"
+                    )
         else:
             self.generator_device = torch.device("cpu")