New smart_inference_mode() conditional decorator (#8957)

New smart_inference_mode()

detect.py

@@ -44,10 +44,10 @@ from utils.dataloaders import IMG_FORMATS, VID_FORMATS, LoadImages, LoadStreams
 from utils.general import (LOGGER, check_file, check_img_size, check_imshow, check_requirements, colorstr, cv2,
                            increment_path, non_max_suppression, print_args, scale_coords, strip_optimizer, xyxy2xywh)
 from utils.plots import Annotator, colors, save_one_box
-from utils.torch_utils import select_device, time_sync
+from utils.torch_utils import select_device, smart_inference_mode, time_sync
 
 
-@torch.no_grad()
+@smart_inference_mode()
 def run(
         weights=ROOT / 'yolov5s.pt',  # model.pt path(s)
         source=ROOT / 'data/images',  # file/dir/URL/glob, 0 for webcam