starlingx/monitoring
Code Issues Proposed changes

False alarm GNSS-signal-loss seen for device of gnss-monitor ptp-instance

Browse Source 
The false alarm seen with following GpsData, where lock_state is 0 and
satellite_count and signal are positive value :
GpsData(gpsd_running=1, lock_state=0, satellite_count=22,
signal_quality_db=SignalQualityDb(min=28.0, max=36.0, avg=32.954))

SKY report of Gpsd data gives satellite count and signal_quality_db.
TPV report of Gpsd data gives lock_state. The code was written with
the assumption: SKY report always received only after TPV report. In long
running system, it is observed the order is not guaranteed (5 out-of-
order receipt in 2 days).

This commit fixes the issue by handling out-of-order TPV and SKY report.
Unit tests has been added to check out-of-order handling.

TEST PLAN:
  PASS: Unit test with out-of-order TPV and SKY reports
  PASS: Deploy gnss-monitor instance and test functionality
  PASS: Run in loop to verify GpsData output
        sudo python /usr/rootdirs/opt/collectd/extensions/python/ptp_gnss_monitor_cli.py --devices /dev/ttyACM0

Closes-bug: 2127121

Change-Id: I80594f5a3a1210213c6f688822711b9c2e4e84a1
Signed-off-by: Tara Nath Subedi <tara.subedi@windriver.com>
This commit is contained in:
Tara Subedi
2025-10-08 12:11:41 -04:00
parent 37a21a504c
commit 611c663625
2 changed files with 298 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
collectd-extensions/src/ptp_gnss_monitor.py
View File

@@ -115,6 +115,12 @@ def get_gps_data_by_session(session, device_path):
signal_quality_db=SignalQualityDb(min=0, max=0, avg=0),
)
try:
# - TPV and SKY report are independent information and could come in any order.
# - A GPS receiver might have satellite visibility data (a SKY report) but still not
# be able to calculate a usable position, hence sending a TPV report with mode: 0.
# - SKY report won't follow TPV, when GPS receiver is not functional.
tpv_report_scanned = False
sky_report_scanned = False
for report in session:
if report["class"] in ["VERSION", "WATCH", "DEVICE"]:
continue
@@ -138,12 +144,17 @@ def get_gps_data_by_session(session, device_path):
message = f"{PLUGIN} {device_path} have not achieved satellite lock: {report}"
collectd.debug(message)
data.lock_state = 0
# reset satellite_count and signal_quality_db
data.satellite_count = 0
data.signal_quality_db = SignalQualityDb(min=0, max=0, avg=0)
# Do not change satellite_count and signal_quality_db in case
# SKY already scanned
break
else:
data.lock_state = 1
if sky_report_scanned:
break
# Set TPV report scanned flag
tpv_report_scanned = True
# device key is optional in SKY class
elif (
report["class"] == "SKY"
@@ -153,14 +164,23 @@ def get_gps_data_by_session(session, device_path):
# uSat key is optional in SKY class, Number of satellites used in navigation solution
if "uSat" in report:
data.satellite_count = report["uSat"]
else:
data.satellite_count = 0
# satellites key is optional in SKY class, List of satellite objects in skyview
if "satellites" in report:
data.signal_quality_db = get_signal_to_noise_ratio(
report["satellites"]
)
else:
data.signal_quality_db = SignalQualityDb(min=0, max=0, avg=0)
# All reports collected, No more polling required.
break
if tpv_report_scanned:
break
# Set SKY report scanned flag
sky_report_scanned = True
except Exception as exc:
# In case of parsing error, should be reported instead of throwing exception
message = f"{PLUGIN} Programming error occured: {type(exc)}:{exc}"

274
collectd-extensions/tests/test_ptp_gnss_monitor.py
View File

@@ -321,6 +321,280 @@ class TestPtpMonitoring(unittest.TestCase):
msg=f"actual {data} not equal to expected {expected_data} ",
)
def test_get_gps_data_by_session_sky_before_tpv_mode_2_valid(self):
# out of order test: SKY before TPV (with mode:2)
device_path = "/dev/gnss0"
session = [
{
"class": "VERSION",
"release": "3.22",
"rev": "3.22",
"proto_major": 3,
"proto_minor": 14,
},
{
"class": "DEVICES",
"devices": [
{
"class": "DEVICE",
"path": "/dev/gnss0",
"activated": "2025-06-13T12:52:15.463Z",
"native": 0,
"bps": 9600,
"parity": "N",
"stopbits": 0,
"cycle": 1.0,
},
{
"class": "DEVICE",
"path": "/dev/gnss1",
"activated": "2025-06-13T12:52:19.637Z",
"native": 0,
"bps": 9600,
"parity": "N",
"stopbits": 0,
"cycle": 1.0,
},
],
},
{
"class": "WATCH",
"enable": True,
"json": True,
"nmea": False,
"raw": 0,
"scaled": False,
"timing": False,
"split24": False,
"pps": False,
},
{
"class": "DEVICE",
"path": "/dev/gnss0",
"driver": "NMEA0183",
"activated": "2025-06-13T12:52:19.637Z",
"native": 0,
"bps": 9600,
"parity": "N",
"stopbits": 0,
"cycle": 1.0,
},
{
"class": "SKY",
"device": "/dev/gnss0",
"time": "2019-04-10T20:27:52.000Z",
"xdop": 0.69,
"ydop": 0.68,
"vdop": 1.33,
"tdop": 0.88,
"hdop": 0.97,
"gdop": 1.86,
"pdop": 1.64,
"nSat": 4,
"uSat": 3,
"satellites": [
{
"PRN": 5,
"el": 31.0,
"az": 86.0,
"ss": 45.2,
"used": True,
"gnssid": 0,
"svid": 5,
"health": 1,
},
{
"PRN": 10,
"el": 10.0,
"az": 278.0,
"ss": 40.0,
"used": False,
"gnssid": 0,
"svid": 10,
"health": 1,
},
{
"PRN": 13,
"el": 44.0,
"az": 53.0,
"ss": 47.4,
"used": True,
"gnssid": 0,
"svid": 13,
"health": 1,
},
{
"PRN": 15,
"el": 80.0,
"az": 68.0,
"ss": 48.8,
"used": True,
"gnssid": 0,
"svid": 15,
"health": 1,
},
],
},
{"class": "TPV", "device": "/dev/gnss0", "mode": 2},
]
snr = [45.2, 47.4, 48.8]
avg = sum(snr) / len(snr)
trunc_avg = int(avg * 1000) / 1000
expected_signal_quality_db = ptp_monitoring.SignalQualityDb(
min=min(snr), max=max(snr), avg=trunc_avg
)
expected_data = ptp_monitoring.GpsData(
gpsd_running=1,
lock_state=1,
satellite_count=3,
signal_quality_db=expected_signal_quality_db,
)
data = ptp_monitoring.get_gps_data_by_session(session, device_path)
mock_collectd.assert_not_called()
self.assertEqual(
data,
expected_data,
msg=f"actual {data} not equal to expected {expected_data} ",
)
def test_get_gps_data_by_session_sky_before_tpv_mode_1_valid(self):
# out of order test: SKY before TPV (with mode:1)
device_path = "/dev/gnss0"
session = [
{
"class": "VERSION",
"release": "3.22",
"rev": "3.22",
"proto_major": 3,
"proto_minor": 14,
},
{
"class": "DEVICES",
"devices": [
{
"class": "DEVICE",
"path": "/dev/gnss0",
"activated": "2025-06-13T12:52:15.463Z",
"native": 0,
"bps": 9600,
"parity": "N",
"stopbits": 0,
"cycle": 1.0,
},
{
"class": "DEVICE",
"path": "/dev/gnss1",
"activated": "2025-06-13T12:52:19.637Z",
"native": 0,
"bps": 9600,
"parity": "N",
"stopbits": 0,
"cycle": 1.0,
},
],
},
{
"class": "WATCH",
"enable": True,
"json": True,
"nmea": False,
"raw": 0,
"scaled": False,
"timing": False,
"split24": False,
"pps": False,
},
{
"class": "DEVICE",
"path": "/dev/gnss0",
"driver": "NMEA0183",
"activated": "2025-06-13T12:52:19.637Z",
"native": 0,
"bps": 9600,
"parity": "N",
"stopbits": 0,
"cycle": 1.0,
},
{
"class": "SKY",
"device": "/dev/gnss0",
"time": "2019-04-10T20:27:52.000Z",
"xdop": 0.69,
"ydop": 0.68,
"vdop": 1.33,
"tdop": 0.88,
"hdop": 0.97,
"gdop": 1.86,
"pdop": 1.64,
"nSat": 4,
"uSat": 3,
"satellites": [
{
"PRN": 5,
"el": 31.0,
"az": 86.0,
"ss": 45.2,
"used": True,
"gnssid": 0,
"svid": 5,
"health": 1,
},
{
"PRN": 10,
"el": 10.0,
"az": 278.0,
"ss": 40.0,
"used": False,
"gnssid": 0,
"svid": 10,
"health": 1,
},
{
"PRN": 13,
"el": 44.0,
"az": 53.0,
"ss": 47.4,
"used": True,
"gnssid": 0,
"svid": 13,
"health": 1,
},
{
"PRN": 15,
"el": 80.0,
"az": 68.0,
"ss": 48.8,
"used": True,
"gnssid": 0,
"svid": 15,
"health": 1,
},
],
},
{"class": "TPV", "device": "/dev/gnss0", "mode": 1},
]
snr = [45.2, 47.4, 48.8]
avg = sum(snr) / len(snr)
trunc_avg = int(avg * 1000) / 1000
expected_signal_quality_db = ptp_monitoring.SignalQualityDb(
min=min(snr), max=max(snr), avg=trunc_avg
)
expected_data = ptp_monitoring.GpsData(
gpsd_running=1,
lock_state=0,
satellite_count=3,
signal_quality_db=expected_signal_quality_db,
)
data = ptp_monitoring.get_gps_data_by_session(session, device_path)
mock_collectd.assert_not_called()
self.assertEqual(
data,
expected_data,
msg=f"actual {data} not equal to expected {expected_data} ",
)
def test_get_gps_data_by_session_with_garbase_data(self):
device_path = "/dev/gnss0"
session = [