fix clas distributed eval bug

ppcls/engine/evaluation/classification.py

@@ -88,12 +88,6 @@ def classification_eval(engine, epoch_id=0):
                                     accum_samples]
                     current_samples = total_samples + current_samples - accum_samples
                 metric_dict = engine.eval_metric_func(pred, labels)
-
-                for key in metric_dict:
-                    paddle.distributed.all_reduce(
-                        metric_dict[key], op=paddle.distributed.ReduceOp.SUM)
-                    metric_dict[key] = metric_dict[
-                        key] / paddle.distributed.get_world_size()
             else:
                 metric_dict = engine.eval_metric_func(out, batch[1])
             for key in metric_dict:
@@ -103,7 +97,7 @@ def classification_eval(engine, epoch_id=0):
                     output_info[key] = AverageMeter(key, '7.5f')
 
                 output_info[key].update(metric_dict[key].numpy()[0],
-                                        batch_size)
+                                        current_samples)
 
         time_info["batch_cost"].update(time.time() - tic)