[PATCH 3/4] iocost_monitor: exit successfully if interval is zero

From: Tejun Heo
Date: Mon Apr 13 2020 - 12:28:36 EST


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 <tj@xxxxxxxxxx>
---
tools/cgroup/iocost_monitor.py | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/cgroup/iocost_monitor.py b/tools/cgroup/iocost_monitor.py
index 7427a5ee761b..eb2363b868c5 100644
--- a/tools/cgroup/iocost_monitor.py
+++ b/tools/cgroup/iocost_monitor.py
@@ -28,7 +28,8 @@ parser.add_argument('devname', metavar='DEV',
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 @@ ioc = None
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()
--
2.25.2