Reduce RAM memory usage by tuning the stack of the stasks and the heap allocated for FreeRTOS.

Add Monitor to log the stack usage of each task.

src/SystemTask/SystemMonitor.h

@@ -0,0 +1,46 @@
+#pragma once
+#include <FreeRTOS.h>
+#include <task.h>
+#include <nrf_log.h>
+
+
+namespace Pinetime {
+  namespace System {
+    struct DummyMonitor {};
+    struct FreeRtosMonitor {};
+
+    template<class T>
+    class SystemMonitor {
+      public:
+        SystemMonitor() = delete;
+    };
+
+    template<>
+    class SystemMonitor<DummyMonitor> {
+      public:
+        void Process() const {}
+    };
+
+    template<>
+    class SystemMonitor<FreeRtosMonitor> {
+      public:
+        void Process() const {
+          if(xTaskGetTickCount() - lastTick > 10000) {
+            NRF_LOG_INFO("---------------------------------------\nFee heap : %d", xPortGetFreeHeapSize());
+            auto nb = uxTaskGetSystemState(tasksStatus, 10, NULL);
+            for (int i = 0; i < nb; i++) {
+              NRF_LOG_INFO("Task [%s] - %d", tasksStatus[i].pcTaskName, tasksStatus[i].usStackHighWaterMark);
+              if (tasksStatus[i].usStackHighWaterMark < 20)
+                NRF_LOG_INFO("WARNING!!! Task %s task is nearly full, only %dB available", tasksStatus[i].pcTaskName,
+                             tasksStatus[i].usStackHighWaterMark * 4);
+            }
+            lastTick = xTaskGetTickCount();
+          }
+        }
+
+      private:
+        mutable TickType_t lastTick = 0;
+        mutable TaskStatus_t tasksStatus[10];
+    };
+  }
+}

src/SystemTask/SystemTask.cpp

@@ -169,6 +169,8 @@ void SystemTask::Work() {
     dateTimeController.UpdateTime(systick_counter);
     batteryController.Update();
 
+    monitor.Process();
+
     if(!nrf_gpio_pin_read(pinButton))
       watchdog.Kick();
   }

src/SystemTask/SystemTask.h

@@ -10,6 +10,7 @@
 #include <drivers/Watchdog.h>
 #include <Components/Ble/NimbleController.h>
 #include <drivers/SpiNorFlash.h>
+#include "SystemMonitor.h"
 
 namespace Pinetime {
   namespace System {
@@ -72,6 +73,12 @@ namespace Pinetime {
         bool doNotGoToSleep = false;
 
         void GoToRunning();
+
+#if configUSE_TRACE_FACILITY == 1
+        SystemMonitor<FreeRtosMonitor> monitor;
+#else
+        SystemMonitor<DummyMonitor> monitor;
+#endif
     };
   }
 }