fixbug: dist test in torch 2.0 (open-mmlab#1602)

* fixbug: torch 2.0 dist train with error local rank

* fixbug: dist test in torch 2.0

Author: jihanyang

tools/scripts/torch_test.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+set -x
+NGPUS=$1
+PY_ARGS=${@:2}
+
+while true
+do
+    PORT=$(( ((RANDOM<<15)|RANDOM) % 49152 + 10000 ))
+    status="$(nc -z 127.0.0.1 $PORT < /dev/null &>/dev/null; echo $?)"
+    if [ "${status}" != "0" ]; then
+        break;
+    fi
+done
+echo $PORT
+
+torchrun --nproc_per_node=${NGPUS} --rdzv_endpoint=localhost:${PORT} test.py --launcher pytorch ${PY_ARGS}
+

tools/test.py

@@ -29,7 +29,7 @@ def parse_config():
     parser.add_argument('--pretrained_model', type=str, default=None, help='pretrained_model')
     parser.add_argument('--launcher', choices=['none', 'pytorch', 'slurm'], default='none')
     parser.add_argument('--tcp_port', type=int, default=18888, help='tcp port for distrbuted training')
-    parser.add_argument('--local_rank', type=int, default=0, help='local rank for distributed training')
+    parser.add_argument('--local_rank', type=int, default=None, help='local rank for distributed training')
     parser.add_argument('--set', dest='set_cfgs', default=None, nargs=argparse.REMAINDER,
                         help='set extra config keys if needed')
 
@@ -145,6 +145,9 @@ def main():
         dist_test = False
         total_gpus = 1
     else:
+        if args.local_rank is None:
+            args.local_rank = int(os.environ.get('LOCAL_RANK', '0'))
+
         total_gpus, cfg.LOCAL_RANK = getattr(common_utils, 'init_dist_%s' % args.launcher)(
             args.tcp_port, args.local_rank, backend='nccl'
         )