common: C++ RateKeeper (#29374)

* c++ RateKeeper

* add to files_common

* use util::random_int

* improve monotor_time

* remove ~ratekeeper
old-commit-hash: 3eef63af9b4f4a25bc4c3a0d6ad450bba9f62205

system/proclogd/main.cc

@@ -1,6 +1,7 @@
 
 #include <sys/resource.h>
 
+#include "common/ratekeeper.h"
 #include "common/util.h"
 #include "system/proclogd/proclog.h"
 
@@ -9,13 +10,15 @@ ExitHandler do_exit;
 int main(int argc, char **argv) {
   setpriority(PRIO_PROCESS, 0, -15);
 
+  RateKeeper rk("proclogd", 0.5);
   PubMaster publisher({"procLog"});
+
   while (!do_exit) {
     MessageBuilder msg;
     buildProcLogMessage(msg);
     publisher.send("procLog", msg);
 
-    util::sleep_for(2000);  // 2 secs
+    rk.keepTime();
   }
 
   return 0;

system/sensord/sensors_qcom2.cc

@@ -9,6 +9,7 @@
 
 #include "cereal/messaging/messaging.h"
 #include "common/i2c.h"
+#include "common/ratekeeper.h"
 #include "common/swaglog.h"
 #include "common/timing.h"
 #include "common/util.h"
@@ -173,10 +174,10 @@ int sensor_loop(I2CBus *i2c_bus_imu) {
   std::thread lsm_interrupt_thread(&interrupt_loop, std::ref(lsm_interrupt_sensors),
                                    std::ref(sensor_service));
 
+  RateKeeper rk("sensord", 100);
+
   // polling loop for non interrupt handled sensors
   while (!do_exit) {
-    std::chrono::steady_clock::time_point begin = std::chrono::steady_clock::now();
-
     for (Sensor *sensor : sensors) {
       MessageBuilder msg;
       if (!sensor->get_event(msg)) {
@@ -190,8 +191,7 @@ int sensor_loop(I2CBus *i2c_bus_imu) {
       pm_non_int.send(sensor_service[sensor].c_str(), msg);
     }
 
-    std::chrono::steady_clock::time_point end = std::chrono::steady_clock::now();
-    std::this_thread::sleep_for(std::chrono::milliseconds(10) - (end - begin));
+    rk.keepTime();
   }
 
   for (Sensor *sensor : sensors) {