The Rate-Monotonic Manager provides facilities to implement tasks which execute in a periodic fashion. Critically, it also gathers information about the execution of those periods and can provide important statistics to the user which can be used to analyze and tune the application. More...

Data Structures
struct	rtems_rate_monotonic_period_statistics
	This structure provides the statistics of a period. More...

struct	rtems_rate_monotonic_period_status
	This structure provides the detailed status of a period. More...

Macros
#define	RTEMS_PERIOD_STATUS WATCHDOG_NO_TIMEOUT
	This constant is the interval passed to the rtems_rate_monotonic_period() directive to obtain status information.

Enumerations
enum	rtems_rate_monotonic_period_states { RATE_MONOTONIC_INACTIVE , RATE_MONOTONIC_ACTIVE , RATE_MONOTONIC_EXPIRED }
	This enumeration defines the states in which a period may be. More...

Functions
rtems_status_code	rtems_rate_monotonic_create (rtems_name name, rtems_id *id)
	Creates a period.

rtems_status_code	rtems_rate_monotonic_ident (rtems_name name, rtems_id *id)
	Identifies a period by the object name.

rtems_status_code	rtems_rate_monotonic_cancel (rtems_id id)
	Cancels the period.

rtems_status_code	rtems_rate_monotonic_delete (rtems_id id)
	Deletes the period.

rtems_status_code	rtems_rate_monotonic_period (rtems_id id, rtems_interval length)
	Concludes the current period and start the next period, or gets the period status.

rtems_status_code	rtems_rate_monotonic_get_status (rtems_id id, rtems_rate_monotonic_period_status *status)
	Gets the detailed status of the period.

rtems_status_code	rtems_rate_monotonic_get_statistics (rtems_id id, rtems_rate_monotonic_period_statistics *status)
	Gets the statistics of the period.

rtems_status_code	rtems_rate_monotonic_reset_statistics (rtems_id id)
	Resets the statistics of the period.

void	rtems_rate_monotonic_reset_all_statistics (void)
	Resets the statistics of all periods.

void	rtems_rate_monotonic_report_statistics (void)
	Reports the period statistics using the printk() printer.

void	rtems_rate_monotonic_report_statistics_with_plugin (const struct rtems_printer *printer)
	Reports the period statistics using the printer plugin.

Detailed Description

The Rate-Monotonic Manager provides facilities to implement tasks which execute in a periodic fashion. Critically, it also gathers information about the execution of those periods and can provide important statistics to the user which can be used to analyze and tune the application.

Enumeration Type Documentation

◆ rtems_rate_monotonic_period_states

enum rtems_rate_monotonic_period_states

This enumeration defines the states in which a period may be.

Enumerator
RATE_MONOTONIC_INACTIVE	This status indicates the period is off the watchdog chain, and has never been initialized.
RATE_MONOTONIC_ACTIVE	This status indicates the period is on the watchdog chain, and running. The owner may be executing or blocked waiting on another object.
RATE_MONOTONIC_EXPIRED	This status indicates the period is off the watchdog chain, and has expired. The owner may still execute and has taken too much time to complete this iteration of the period.

Function Documentation

◆ rtems_rate_monotonic_cancel()

rtems_status_code rtems_rate_monotonic_cancel ( rtems_id id )

Cancels the period.

Parameters

id	is the rate monotonic period identifier.

This directive cancels the rate monotonic period specified by id. This period may be reinitiated by the next invocation of rtems_rate_monotonic_period().

Return values

RTEMS_SUCCESSFUL	The requested operation was successful.
RTEMS_INVALID_ID	There was no rate monotonic period associated with the identifier specified by `id`.
RTEMS_NOT_OWNER_OF_RESOURCE	The rate monotonic period was not created by the calling task.

Constraints

The following constraints apply to this directive:

The directive may be called from within task context.
The directive will not cause the calling task to be preempted.
The directive may be used exclusively by the task which created the associated object.

◆ rtems_rate_monotonic_create()

rtems_status_code rtems_rate_monotonic_create	(	rtems_name	name,
		rtems_id *	id
	)

Creates a period.

Parameters

	name	is the object name of the period.
[out]	id	is the pointer to an rtems_id object. When the directive call is successful, the identifier of the created period will be stored in this object.

This directive creates a period which resides on the local node. The period has the user-defined object name specified in name The assigned object identifier is returned in id. This identifier is used to access the period with other rate monotonic related directives.

Return values

RTEMS_SUCCESSFUL	The requested operation was successful.
RTEMS_INVALID_NAME	The `name` parameter was invalid.
RTEMS_TOO_MANY	There was no inactive object available to create a period. The number of periods available to the application is configured through the CONFIGURE_MAXIMUM_PERIODS application configuration option.

Notes

The calling task is registered as the owner of the created period. Some directives can be only used by this task for the created period.

For control and maintenance of the period, RTEMS allocates a PCB from the local PCB free pool and initializes it.

Constraints

The following constraints apply to this directive:

The directive may be called from within device driver initialization context.
The directive may be called from within task context.
The directive may obtain and release the object allocator mutex. This may cause the calling task to be preempted.
The number of periods available to the application is configured through the CONFIGURE_MAXIMUM_PERIODS application configuration option.
Where the object class corresponding to the directive is configured to use unlimited objects, the directive may allocate memory from the RTEMS Workspace.

◆ rtems_rate_monotonic_delete()

rtems_status_code rtems_rate_monotonic_delete ( rtems_id id )

Deletes the period.

Parameters

id	is the period identifier.

This directive deletes the period specified by id. If the period is running, it is automatically canceled.

Return values

RTEMS_SUCCESSFUL	The requested operation was successful.
RTEMS_INVALID_ID	There was no period associated with the identifier specified by `id`.

Notes: The PCB for the deleted period is reclaimed by RTEMS.

Constraints

The following constraints apply to this directive:

The directive may be called from within device driver initialization context.
The directive may be called from within task context.
The directive may obtain and release the object allocator mutex. This may cause the calling task to be preempted.
The calling task does not have to be the task that created the object. Any local task that knows the object identifier can delete the object.
Where the object class corresponding to the directive is configured to use unlimited objects, the directive may free memory to the RTEMS Workspace.

◆ rtems_rate_monotonic_get_statistics()

rtems_status_code rtems_rate_monotonic_get_statistics	(	rtems_id	id,
		rtems_rate_monotonic_period_statistics *	status
	)

Gets the statistics of the period.

Parameters

	id	is the rate monotonic period identifier.
[out]	status	is the pointer to an rtems_rate_monotonic_period_statistics object. When the directive call is successful, the period statistics will be stored in this object.

This directive returns the statistics of the rate monotonic period specified by id. The statistics of the period will be returned in the members of the period statistics object referenced by status:

The count member is set to the number of periods executed.
The missed_count member is set to the number of periods missed.
The min_cpu_time member is set to the least amount of processor time used in the period.
The max_cpu_time member is set to the highest amount of processor time used in the period.
The total_cpu_time member is set to the total amount of processor time used in the period.
The min_wall_time member is set to the least amount of CLOCK_MONOTONIC time used in the period.
The max_wall_time member is set to the highest amount of CLOCK_MONOTONIC time used in the period.
The total_wall_time member is set to the total amount of CLOCK_MONOTONIC time used in the period.

Return values

RTEMS_SUCCESSFUL	The requested operation was successful.
RTEMS_INVALID_ID	There was no rate monotonic period associated with the identifier specified by `id`.
RTEMS_INVALID_ADDRESS	The `status` parameter was NULL.

Constraints

The following constraints apply to this directive:

The directive may be called from within task context.
The directive may be called from within interrupt context.
The directive will not cause the calling task to be preempted.

◆ rtems_rate_monotonic_get_status()

rtems_status_code rtems_rate_monotonic_get_status	(	rtems_id	id,
		rtems_rate_monotonic_period_status *	status
	)

Gets the detailed status of the period.

Parameters

	id	is the rate monotonic period identifier.
[out]	status	is the pointer to an rtems_rate_monotonic_period_status object. When the directive call is successful, the detailed period status will be stored in this object.

This directive returns the detailed status of the rate monotonic period specified by id. The detailed status of the period will be returned in the members of the period status object referenced by status:

The owner member is set to the identifier of the owner task of the period.
The state member is set to the current state of the period.
The postponed_jobs_count member is set to the count of jobs which are not released yet.
If the current state of the period is RATE_MONOTONIC_INACTIVE, the since_last_period and executed_since_last_period members will be set to zero. Otherwise, both members will contain time information since the last successful invocation of the rtems_rate_monotonic_period() directive by the owner task. More specifically, the since_last_period member will be set to the time elapsed since the last successful invocation. The executed_since_last_period member will be set to the processor time consumed by the owner task since the last successful invocation.

Return values

RTEMS_SUCCESSFUL	The requested operation was successful.
RTEMS_INVALID_ID	There was no rate monotonic period associated with the identifier specified by `id`.
RTEMS_INVALID_ADDRESS	The `status` parameter was NULL.

Constraints

The following constraints apply to this directive:

The directive may be called from within task context.
The directive may be called from within interrupt context.
The directive will not cause the calling task to be preempted.

◆ rtems_rate_monotonic_ident()

rtems_status_code rtems_rate_monotonic_ident	(	rtems_name	name,
		rtems_id *	id
	)

Identifies a period by the object name.

Parameters

	name	is the object name to look up.
[out]	id	is the pointer to an rtems_id object. When the directive call is successful, the object identifier of an object with the specified name will be stored in this object.

This directive obtains a period identifier associated with the period name specified in name.

Return values

RTEMS_SUCCESSFUL	The requested operation was successful.
RTEMS_INVALID_ADDRESS	The `id` parameter was NULL.
RTEMS_INVALID_NAME	The `name` parameter was 0.
RTEMS_INVALID_NAME	There was no object with the specified name on the local node.

Notes

If the period name is not unique, then the period identifier will match the first period with that name in the search order. However, this period identifier is not guaranteed to correspond to the desired period.

The objects are searched from lowest to the highest index. Only the local node is searched.

The period identifier is used with other rate monotonic related directives to access the period.

Constraints

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

◆ rtems_rate_monotonic_period()

rtems_status_code rtems_rate_monotonic_period	(	rtems_id	id,
		rtems_interval	length
	)

Concludes the current period and start the next period, or gets the period status.

Parameters

id	is the rate monotonic period identifier.
length	is the period length in clock ticks or RTEMS_PERIOD_STATUS to get the period status.

This directive initiates the rate monotonic period specified by id with a length of period ticks specified by length. If the period is running, then the calling task will block for the remainder of the period before reinitiating the period with the specified period length. If the period was not running (either expired or never initiated), the period is immediately initiated and the directive returns immediately. If the period has expired, the postponed job will be released immediately and the following calls of this directive will release postponed jobs until there is no more deadline miss.

If invoked with a period length of RTEMS_PERIOD_STATUS ticks, the current state of the period will be returned. The directive status indicates the current state of the period. This does not alter the state or period length of the period.

Return values

RTEMS_SUCCESSFUL	The requested operation was successful.
RTEMS_INVALID_ID	There was no rate monotonic period associated with the identifier specified by `id`.
RTEMS_NOT_OWNER_OF_RESOURCE	The rate monotonic period was not created by the calling task.
RTEMS_NOT_DEFINED	The rate monotonic period has never been initiated (only possible when the `length` parameter was equal to RTEMS_PERIOD_STATUS).
RTEMS_TIMEOUT	The rate monotonic period has expired.

Notes: Resetting the processor usage time of tasks has no impact on the period status and statistics.

Constraints

The following constraints apply to this directive:

The directive may be called from within task context.
The directive may be used exclusively by the task which created the associated object.

◆ rtems_rate_monotonic_report_statistics()

void rtems_rate_monotonic_report_statistics ( void )

Reports the period statistics using the printk() printer.

This directive prints a report on all active periods which have executed at least one period using the printk() printer.

Constraints

The following constraints apply to this directive:

The directive may be called from within task context.
The directive may obtain and release the object allocator mutex. This may cause the calling task to be preempted.

◆ rtems_rate_monotonic_report_statistics_with_plugin()

void rtems_rate_monotonic_report_statistics_with_plugin ( const struct rtems_printer * printer )

Reports the period statistics using the printer plugin.

Parameters

printer is the printer plugin to output the report.

This directive prints a report on all active periods which have executed at least one period using the printer plugin specified by printer.

Constraints

The following constraints apply to this directive:

The directive may be called from within task context.
The directive may obtain and release the object allocator mutex. This may cause the calling task to be preempted.

◆ rtems_rate_monotonic_reset_all_statistics()

void rtems_rate_monotonic_reset_all_statistics ( void )

Resets the statistics of all periods.

This directive resets the statistics information associated with all rate monotonic period instances.

Constraints

The following constraints apply to this directive:

The directive may be called from within task context.
The directive may obtain and release the object allocator mutex. This may cause the calling task to be preempted.

◆ rtems_rate_monotonic_reset_statistics()

rtems_status_code rtems_rate_monotonic_reset_statistics ( rtems_id id )

Resets the statistics of the period.

Parameters

id	is the rate monotonic period identifier.

This directive resets the statistics of the rate monotonic period specified by id.

Return values

RTEMS_SUCCESSFUL	The requested operation was successful.
RTEMS_INVALID_ID	There was no rate monotonic period associated with the identifier specified by `id`.

Constraints

The following constraints apply to this directive:

The directive may be called from within task context.
The directive may be called from within interrupt context.
The directive will not cause the calling task to be preempted.

Data Structures

Macros

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

◆ rtems_rate_monotonic_period_states

Function Documentation

◆ rtems_rate_monotonic_cancel()

◆ rtems_rate_monotonic_create()

◆ rtems_rate_monotonic_delete()

◆ rtems_rate_monotonic_get_statistics()

◆ rtems_rate_monotonic_get_status()

◆ rtems_rate_monotonic_ident()

◆ rtems_rate_monotonic_period()

◆ rtems_rate_monotonic_report_statistics()

◆ rtems_rate_monotonic_report_statistics_with_plugin()

◆ rtems_rate_monotonic_reset_all_statistics()

◆ rtems_rate_monotonic_reset_statistics()