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/**
 * @file test_microbench_hrt.cpp
 * Tests for the microbench high resolution timer.
 */

#include <unit_test.h>

#include <time.h>
#include <stdlib.h>
#include <unistd.h>

#include <drivers/drv_hrt.h>
#include <perf/perf_counter.h>
#include <px4_platform_common/px4_config.h>
#include <px4_platform_common/micro_hal.h>

namespace MicroBenchHRT
{

#ifdef __PX4_NUTTX
#include <nuttx/irq.h>
static irqstate_t flags;
#endif

void lock()
{
#ifdef __PX4_NUTTX
	flags = px4_enter_critical_section();
#endif
}

void unlock()
{
#ifdef __PX4_NUTTX
	px4_leave_critical_section(flags);
#endif
}

#define PERF(name, op, count) do { \
		px4_usleep(1000); \
		reset(); \
		perf_counter_t p = perf_alloc(PC_ELAPSED, name); \
		for (int i = 0; i < count; i++) { \
			px4_usleep(1); \
			lock(); \
			perf_begin(p); \
			op; \
			perf_end(p); \
			unlock(); \
			reset(); \
		} \
		perf_print_counter(p); \
		perf_free(p); \
	} while (0)

class MicroBenchHRT : public UnitTest
{
public:
	virtual bool run_tests();

private:

	bool time_px4_hrt();

	void reset();

	void lock()
	{
#ifdef __PX4_NUTTX
		flags = px4_enter_critical_section();
#endif
	}

	void unlock()
	{
#ifdef __PX4_NUTTX
		px4_leave_critical_section(flags);
#endif
	}

	uint64_t u_64;
	uint64_t u_64_out;
};

bool MicroBenchHRT::run_tests()
{
	ut_run_test(time_px4_hrt);

	return (_tests_failed == 0);
}

template<typename T>
T random(T min, T max)
{
	const T scale = rand() / (T) RAND_MAX; /* [0, 1.0] */
	return min + scale * (max - min);      /* [min, max] */
}

void MicroBenchHRT::reset()
{
	srand(time(nullptr));

	// initialize with random data
	u_64 = rand();
	u_64_out = rand();
}

ut_declare_test_c(test_microbench_hrt, MicroBenchHRT)

bool MicroBenchHRT::time_px4_hrt()
{
	PERF("hrt_absolute_time()", u_64_out = hrt_absolute_time(), 1000);
	PERF("hrt_elapsed_time()", u_64_out = hrt_elapsed_time(&u_64), 1000);
	PERF("hrt_elapsed_time_atomic()", u_64_out = hrt_elapsed_time_atomic(&u_64), 1000);

	return true;
}

} // namespace MicroBenchHRT