watchdog.h

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#pragma once

#include <drivers/drv_hrt.h>

#ifdef __PX4_NUTTX
#include <sched.h>
#include <systemlib/cpuload.h>
#endif /* __PX4_NUTTX */

namespace px4
{
namespace logger
{

struct watchdog_data_t {
#ifdef __PX4_NUTTX
    int logger_main_task_index = -1;
    int logger_writer_task_index = -1;
    hrt_abstime ready_to_run_timestamp = hrt_absolute_time();
    uint8_t last_state = TSTATE_TASK_INVALID;
#endif /* __PX4_NUTTX */
};


/**
 * Initialize the watchdog, fill in watchdog_data.
 */
void watchdog_initialize(const pid_t pid_logger_main, const pthread_t writer_thread, watchdog_data_t &watchdog_data);

/**
 * Update the watchdog and trigger it if necessary. It is triggered when the log writer task is in
 * ready state for a certain period of time, but did not get scheduled. It means that most likely
 * some other higher-prio task runs busy.
 * When the watchdog triggers, it boosts the priority of the logger's main & writer tasks to maximum, so
 * that they get scheduled again.
 *
 * Expected to be called from IRQ context.
 *
 * @param watchdog_data
 * @return true if watchdog is triggered, false otherwise
 */
bool watchdog_update(watchdog_data_t &watchdog_data);

} //namespace logger
} //namespace px4