Performance measuring tools. More...

#include <stdint.h>
#include <px4_defines.h>

Macros
#define	_SYSTEMLIB_PERF_COUNTER_H value

#define	LATENCY_BUCKET_COUNT 8

Typedefs
typedef struct perf_ctr_header *	perf_counter_t

typedef void(*	perf_callback) (perf_counter_t handle, void *user)

Enumerations
enum	perf_counter_type { PC_COUNT, PC_ELAPSED, PC_INTERVAL }
	Counter types. More...

Functions
__BEGIN_DECLS __EXPORT perf_counter_t	perf_alloc (enum perf_counter_type type, const char *name)
	Create a new local counter. More...

__EXPORT perf_counter_t	perf_alloc_once (enum perf_counter_type type, const char *name)
	Get the reference to an existing counter or create a new one if it does not exist. More...

__EXPORT void	perf_free (perf_counter_t handle)
	Free a counter. More...

__EXPORT void	perf_count (perf_counter_t handle)
	Count a performance event. More...

__EXPORT void	perf_begin (perf_counter_t handle)
	Begin a performance event. More...

__EXPORT void	perf_end (perf_counter_t handle)
	End a performance event. More...

__EXPORT void	perf_set_elapsed (perf_counter_t handle, int64_t elapsed)
	Register a measurement. More...

__EXPORT void	perf_set_count (perf_counter_t handle, uint64_t count)
	Set a counter. More...

__EXPORT void	perf_cancel (perf_counter_t handle)
	Cancel a performance event. More...

__EXPORT void	perf_reset (perf_counter_t handle)
	Reset a performance counter. More...

__EXPORT void	perf_print_counter (perf_counter_t handle)
	Print one performance counter to stdout. More...

__EXPORT void	perf_print_counter_fd (int fd, perf_counter_t handle)
	Print one performance counter to a fd. More...

__EXPORT int	perf_print_counter_buffer (char *buffer, int length, perf_counter_t handle)
	Print one performance counter to a buffer. More...

__EXPORT void	perf_print_all (int fd)
	Print all of the performance counters. More...

__EXPORT void	perf_iterate_all (perf_callback cb, void *user)
	Iterate over all performance counters using a callback. More...

__EXPORT void	perf_print_latency (int fd)
	Print hrt latency counters. More...

__EXPORT void	perf_reset_all (void)
	Reset all of the performance counters.

__EXPORT uint64_t	perf_event_count (perf_counter_t handle)
	Return current event_count. More...

Variables
const uint16_t	latency_bucket_count

const uint16_t	latency_buckets [LATENCY_BUCKET_COUNT]

uint32_t	latency_counters [LATENCY_BUCKET_COUNT+1]

Detailed Description

Performance measuring tools.

Enumeration Type Documentation

§ perf_counter_type

enum perf_counter_type

Counter types.

Enumerator
PC_COUNT	count the number of times an event occurs
PC_ELAPSED	measure the time elapsed performing an event
PC_INTERVAL	measure the interval between instances of an event

Function Documentation

§ perf_alloc()

__BEGIN_DECLS __EXPORT perf_counter_t perf_alloc	(	enum perf_counter_type	type,
		const char *	name
	)

Create a new local counter.

Parameters

type	The type of the new counter.
name	The counter name.

Returns: Handle for the new counter, or NULL if a counter could not be allocated.

§ perf_alloc_once()

__EXPORT perf_counter_t perf_alloc_once	(	enum perf_counter_type	type,
		const char *	name
	)

Get the reference to an existing counter or create a new one if it does not exist.

Parameters

type	The type of the counter.
name	The counter name.

Returns: Handle for the counter, or NULL if a counter could not be allocated.

§ perf_begin()

__EXPORT void perf_begin ( perf_counter_t handle )

Begin a performance event.

This call applies to counters that operate over ranges of time; PC_ELAPSED etc.

Parameters

handle The handle returned from perf_alloc.

§ perf_cancel()

__EXPORT void perf_cancel ( perf_counter_t handle )

Cancel a performance event.

This call applies to counters that operate over ranges of time; PC_ELAPSED etc. It reverts the effect of a previous perf_begin.

Parameters

handle The handle returned from perf_alloc.

§ perf_count()

__EXPORT void perf_count ( perf_counter_t handle )

Count a performance event.

This call only affects counters that take single events; PC_COUNT, PC_INTERVAL etc.

Parameters

handle The handle returned from perf_alloc.

§ perf_end()

__EXPORT void perf_end ( perf_counter_t handle )

End a performance event.

This call applies to counters that operate over ranges of time; PC_ELAPSED etc. If a call is made without a corresponding perf_begin call, or if perf_cancel has been called subsequently, no change is made to the counter.

Parameters

handle The handle returned from perf_alloc.

§ perf_event_count()

__EXPORT uint64_t perf_event_count ( perf_counter_t handle )

Return current event_count.

Parameters

handle The counter returned from perf_alloc.

Returns: event_count

§ perf_free()

__EXPORT void perf_free ( perf_counter_t handle )

Free a counter.

Parameters

handle The performance counter's handle.

§ perf_iterate_all()

__EXPORT void perf_iterate_all	(	perf_callback	cb,
		void *	user
	)

Iterate over all performance counters using a callback.

Caution: This will aquire the mutex, so do not call any other perf_* method that aquire the mutex as well from the callback (If this is needed, configure the mutex to be reentrant).

Parameters

cb	callback method
user	custom argument for the callback

§ perf_print_all()

__EXPORT void perf_print_all ( int fd )

Print all of the performance counters.

Parameters

fd	File descriptor to print to - e.g. 0 for stdout

§ perf_print_counter()

__EXPORT void perf_print_counter ( perf_counter_t handle )

Print one performance counter to stdout.

Parameters

handle The counter to print.

§ perf_print_counter_buffer()

__EXPORT int perf_print_counter_buffer	(	char *	buffer,
		int	length,
		perf_counter_t	handle
	)

Print one performance counter to a buffer.

Parameters

buffer	buffer to write to
length	buffer length
handle	The counter to print.
return	number of bytes written

§ perf_print_counter_fd()

__EXPORT void perf_print_counter_fd	(	int	fd,
		perf_counter_t	handle
	)

Print one performance counter to a fd.

Parameters

fd	File descriptor to print to - e.g. 0 for stdout
handle	The counter to print.

§ perf_print_latency()

__EXPORT void perf_print_latency ( int fd )

Print hrt latency counters.

Parameters

fd	File descriptor to print to - e.g. 0 for stdout

§ perf_reset()

__EXPORT void perf_reset ( perf_counter_t handle )

Reset a performance counter.

This call resets performance counter to initial state

Parameters

handle The handle returned from perf_alloc.

§ perf_set_count()

__EXPORT void perf_set_count	(	perf_counter_t	handle,
		uint64_t	count
	)

Set a counter.

This call applies to counters of type PC_COUNT. It (re-)sets the count.

Parameters

handle	The handle returned from perf_alloc.
count	The counter value to be set.

§ perf_set_elapsed()

__EXPORT void perf_set_elapsed	(	perf_counter_t	handle,
		int64_t	elapsed
	)

Register a measurement.

This call applies to counters that operate over ranges of time; PC_ELAPSED etc. If a call is made without a corresponding perf_begin call. It sets the value provided as argument as a new measurement.

Parameters

handle	The handle returned from perf_alloc.
elapsed	The time elapsed. Negative values lead to incrementing the overrun counter.

Macros

Typedefs

Enumerations

Functions

Variables

Detailed Description

Enumeration Type Documentation

§ perf_counter_type

Function Documentation

§ perf_alloc()

§ perf_alloc_once()

§ perf_begin()

§ perf_cancel()

§ perf_count()

§ perf_end()

§ perf_event_count()

§ perf_free()

§ perf_iterate_all()

§ perf_print_all()

§ perf_print_counter()

§ perf_print_counter_buffer()

§ perf_print_counter_fd()

§ perf_print_latency()

§ perf_reset()

§ perf_set_count()

§ perf_set_elapsed()