Method _monitor_thread

libraries/AP_HAL_ChibiOS/Scheduler.cpp:415–519

#if HAL_MONITOR_THREAD_ENABLED
void Scheduler::_monitor_thread(void *arg)
{
    Scheduler *sched = (Scheduler *)arg;
    chRegSetThreadName("monitor");

    while (!sched->_initialized) {
        sched->delay(100);
    }
    bool using_watchdog = AP_BoardConfig::watchdog_enabled();
#if HAL_LOGGING_ENABLED
    uint8_t log_wd_counter = 0;
#endif

    while (true) {
        sched->delay(100);
        if (using_watchdog) {
            stm32_watchdog_save((uint32_t *)&hal.util->persistent_data, (sizeof(hal.util->persistent_data)+3)/4);
        }

        // if running memory guard then check all allocations
        malloc_check(nullptr);

        uint32_t now = AP_HAL::millis();
        uint32_t loop_delay = now - sched->last_watchdog_pat_ms;
        if (loop_delay >= 200) {
            // the main loop has been stuck for at least
            // 200ms. Starting logging the main loop state
#if HAL_LOGGING_ENABLED
            const AP_HAL::Util::PersistentData &pd = hal.util->persistent_data;
            if (AP_Logger::get_singleton()) {
                const struct log_MON mon{
                    LOG_PACKET_HEADER_INIT(LOG_MON_MSG),
                    time_us               : AP_HAL::micros64(),
                    loop_delay            : loop_delay,
                    current_task          : pd.scheduler_task,
                    internal_error_mask   : pd.internal_errors,
                    internal_error_count  : pd.internal_error_count,
                    internal_error_line   : pd.internal_error_last_line,
                    mavmsg                : pd.last_mavlink_msgid,
                    mavcmd                : pd.last_mavlink_cmd,
                    semline               : pd.semaphore_line,
                    spicnt                : pd.spi_count,
                    i2ccnt                : pd.i2c_count
                };
                AP::logger().WriteCriticalBlock(&mon, sizeof(mon));
            }
#endif
        }
        if (loop_delay >= 500 && !sched->in_expected_delay()) {
            // at 500ms we declare an internal error
            AP::internalerror().error(AP_InternalError::error_t::main_loop_stuck, hal.util->persistent_data.semaphore_line);
            /*
              if we are armed and get this condition then it is likely
              a lock ordering deadlock. If the main thread is waiting
              on a mutex then we try to force release the mutex from
              the thread that is holding it.
            */
            try_force_mutex();