common/params: support nonblocking write (#29808)

* Safe and efficient asynchronous writing parameters

* call putNonBlocking in locationd

* remove space

* ->AsyncWriter

* remove semicolon

* use member function

* asyc write multiple times

* add test case for AsyncWriter

* merge master

* add missing include

* public

* cleanup

* create once

* cleanup

* update that

* explicit waiting

* improve test case

* pass prefix to asywriter

* move to params

* assert(queue.empty())

* add comment

* add todo

* test_power_monitoring: remove patch

* rm laikad.py

* fix import

---------

Co-authored-by: Adeeb Shihadeh <adeebshihadeh@gmail.com>
old-commit-hash: 3c4c4d1f7f22884f84f0f52ad45ab0412fab1eb5

selfdrive/locationd/calibrationd.py

@@ -15,7 +15,7 @@ from typing import List, NoReturn, Optional
 from cereal import log
 import cereal.messaging as messaging
 from openpilot.common.conversions import Conversions as CV
-from openpilot.common.params import Params, put_nonblocking
+from openpilot.common.params import Params
 from openpilot.common.realtime import set_realtime_priority
 from openpilot.common.transformations.orientation import rot_from_euler, euler_from_rot
 from openpilot.common.swaglog import cloudlog
@@ -64,8 +64,8 @@ class Calibrator:
     self.not_car = False
 
     # Read saved calibration
-    params = Params()
-    calibration_params = params.get("CalibrationParams")
+    self.params = Params()
+    calibration_params = self.params.get("CalibrationParams")
     rpy_init = RPY_INIT
     wide_from_device_euler = WIDE_FROM_DEVICE_EULER_INIT
     height = HEIGHT_INIT
@@ -164,7 +164,7 @@ class Calibrator:
 
     write_this_cycle = (self.idx == 0) and (self.block_idx % (INPUTS_WANTED//5) == 5)
     if self.param_put and write_this_cycle:
-      put_nonblocking("CalibrationParams", self.get_msg(True).to_bytes())
+      self.params.put_nonblocking("CalibrationParams", self.get_msg(True).to_bytes())
 
   def handle_v_ego(self, v_ego: float) -> None:
     self.v_ego = v_ego

selfdrive/locationd/locationd.cc

@@ -678,9 +678,10 @@ void Localizer::configure_gnss_source(const LocalizerGnssSource &source) {
 }
 
 int Localizer::locationd_thread() {
+  Params params;
   LocalizerGnssSource source;
   const char* gps_location_socket;
-  if (Params().getBool("UbloxAvailable")) {
+  if (params.getBool("UbloxAvailable")) {
     source = LocalizerGnssSource::UBLOX;
     gps_location_socket = "gpsLocationExternal";
   } else {
@@ -737,10 +738,7 @@ int Localizer::locationd_thread() {
         VectorXd posGeo = this->get_position_geodetic();
         std::string lastGPSPosJSON = util::string_format(
           "{\"latitude\": %.15f, \"longitude\": %.15f, \"altitude\": %.15f}", posGeo(0), posGeo(1), posGeo(2));
-
-        std::thread([] (const std::string gpsjson) {
-          Params().put("LastGPSPosition", gpsjson);
-        }, lastGPSPosJSON).detach();
+        params.putNonBlocking("LastGPSPosition", lastGPSPosJSON);
       }
       cnt++;
     }

selfdrive/locationd/paramsd.py

@@ -7,7 +7,7 @@ import numpy as np
 import cereal.messaging as messaging
 from cereal import car
 from cereal import log
-from openpilot.common.params import Params, put_nonblocking
+from openpilot.common.params import Params
 from openpilot.common.realtime import config_realtime_process, DT_MDL
 from openpilot.common.numpy_fast import clip
 from openpilot.selfdrive.locationd.models.car_kf import CarKalman, ObservationKind, States
@@ -251,7 +251,7 @@ def main():
           'stiffnessFactor': liveParameters.stiffnessFactor,
           'angleOffsetAverageDeg': liveParameters.angleOffsetAverageDeg,
         }
-        put_nonblocking("LiveParameters", json.dumps(params))
+        params_reader.put_nonblocking("LiveParameters", json.dumps(params))
 
       pm.send('liveParameters', msg)