dvfs_unit.h File Reference

Structures and functions related to DVFS units (group of cores running at the same frequency). More...

Go to the source code of this file.

Data Structures
struct	dvfs_unit
	A DVFS unit. More...

Functions
int	dvfs_unit_open (dvfs_unit **ppUnit, unsigned int nb_cores, dvfs_core **cores, unsigned int unit_id)
	Creates a new DVFS unit in charge of the provided cores. More...
int	dvfs_unit_close (dvfs_unit *unit)
	Frees the memory associated to a DVFS unit and restore their DVFS state. More...
int	dvfs_unit_set_gov (const dvfs_unit *unit, const char *gov)
	Sets a governor on all the cores we are in charge of. More...
int	dvfs_unit_set_freq (const dvfs_unit *unit, unsigned int freq)
	Sets the given frequency on all the unit cores. More...
int	dvfs_unit_get_nb_cores (const dvfs_unit *unit, unsigned int *pNbCores)
	Gets te number of cores available in this DVFS unit. More...
int	dvfs_unit_get_core (const dvfs_unit *unit, dvfs_core **ppCore, unsigned int id)
	Gets the core with the given id if it is part of this DVFS unit, or NULL otherwise. More...
int	dvfs_unit_get_freq (const dvfs_unit *unit, unsigned int *pFreq)
	Gets the frequency currently set for the current DVFS unit. More...
int	dvfs_unit_get_id (const dvfs_unit *unit, unsigned int *pID)
	Returns the index of the considered DVFS unit as stored in the corresponding DVFS context structure array. More...

Detailed Description

Structures and functions related to DVFS units (group of cores running at the same frequency).

See also

dvfs_core

Function Documentation

int dvfs_unit_close

(

dvfs_unit *

unit

)

Frees the memory associated to a DVFS unit and restore their DVFS state.

You are not supposed to directly call this function; use rather dvfs_stop(). It calls

See also

dvfs_core_close() on every

dvfs_core avaiable in this unit.

Parameters

unit	The DVFS unit to close.

Returns

Return values

DVFS_SUCCESS	if everything goes right.
DVFS_ERROR_INVALID_ARG	if unit or cores are NULL.

See also

dvfs_unit_open()

int dvfs_unit_get_core	(	const dvfs_unit *	unit,
		dvfs_core **	ppCore,
		unsigned int	id
	)

Gets the core with the given id if it is part of this DVFS unit, or NULL otherwise.

Parameters

unit	The DVFS unit.
ppCore	the

See also

dvfs_core identified by id

Parameters

id	The core id.

Returns

Return values

DVFS_SUCCESS	if everything goes right.
DVFS_ERROR_INVALID_ARG	if unit or ppCore are NULL.
DVFS_ERROR_INVALID_CORE_ID	the id did not match any core.

int dvfs_unit_get_freq	(	const dvfs_unit *	unit,
		unsigned int *	pFreq
	)

Gets the frequency currently set for the current DVFS unit.

Parameters

unit	The DVFS unit.
pFreq	the frequency currently set for the current DVFS unit.

Returns

Return values

DVFS_SUCCESS	if everything goes right.
DVFS_ERROR_INVALID_ARG	if unit or pFreq are NULL.

int dvfs_unit_get_id	(	const dvfs_unit *	unit,
		unsigned int *	pID
	)

Returns the index of the considered DVFS unit as stored in the corresponding DVFS context structure array.

Parameters

unit	The DVFS unit.
pID	the index of this DVFS unit.

Returns

Return values

DVFS_SUCCESS	if everything goes right.
DVFS_ERROR_INVALID_ARG	if unit or pID are NULL.

int dvfs_unit_get_nb_cores	(	const dvfs_unit *	unit,
		unsigned int *	pNbCores
	)

Gets te number of cores available in this DVFS unit.

Parameters

unit	The DVFS unit.
pNbCores	Will be filled with the number of cores.

Returns

Return values

DVFS_SUCCESS	if everything goes right.
DVFS_ERROR_INVALID_ARG	if unit or ppCore are NULL.

int dvfs_unit_open	(	dvfs_unit **	ppUnit,
		unsigned int	nb_cores,
		dvfs_core **	cores,
		unsigned int	unit_id
	)

Creates a new DVFS unit in charge of the provided cores.

You are not supposed to directly call this function, use rather dvfs_start().

Parameters

ppUnit	pointer where the DVFS Unit instance will be placed
nb_cores	The number of cores the unit handles.
cores	The array of cores to handle. The array itself is freed when calling dvfs_unit_close().
unit_id	the ID of this DVFS unit.

Returns

Return values

DVFS_SUCCESS	if everything goes right.
DVFS_ERROR_INVALID_ARG	if ppUnit or cores are NULL.
DVFS_ERROR_MEM_ALLOC_FAILED	if memory allocation failed.

See also

dvfs_unit_close()

dvfs_core

int dvfs_unit_set_freq	(	const dvfs_unit *	unit,
		unsigned int	freq
	)

Sets the given frequency on all the unit cores.

The effect is unknown if the current governor is not "userspace".

Parameters

unit	The DVFS unit.
freq	The frequency to set.

Returns

Return values

DVFS_SUCCESS	if everything goes right.
DVFS_ERROR_INVALID_ARG	if unit is NULL.

int dvfs_unit_set_gov	(	const dvfs_unit *	unit,
		const char *	gov
	)

Sets a governor on all the cores we are in charge of.

Parameters

unit	The DVFS unit.
gov	The governor to set.

Returns

Return values

DVFS_SUCCESS	if everything goes right.
DVFS_ERROR_INVALID_ARG	if unit or gov are NULL.