iocost_monitor: exit successfully if interval is zero

This is to help external tools to decide whether iocost_monitor has all its requirements met or not based on the exit status of an -i0 run. Signed-off-by: Tejun Heo <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
chewitt · Apr 30, 2020 · f4fe3ea · f4fe3ea
1 parent cd00650
commit f4fe3ea
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/tools/cgroup/iocost_monitor.py b/tools/cgroup/iocost_monitor.py
@@ -28,7 +28,8 @@
 parser.add_argument('--cgroup', action='append', metavar='REGEX',
                     help='Regex for target cgroups, ')
 parser.add_argument('--interval', '-i', metavar='SECONDS', type=float, default=1,
-                    help='Monitoring interval in seconds')
+                    help='Monitoring interval in seconds (0 exits immediately '
+                    'after checking requirements)')
 parser.add_argument('--json', action='store_true',
                     help='Output in json')
 args = parser.parse_args()
@@ -243,6 +244,9 @@ def table_row_str(self, path):
 if ioc is None:
     err(f'Could not find ioc for {devname}');
 
+if interval == 0:
+    sys.exit(0)
+
 # Keep printing
 while True:
     now = time.time()