CPUFreq_Userspace Class Reference

Class to control one CPU's frequency by the powersave daemon. More...

#include <cpufreq_interface.h>

Inheritance diagram for CPUFreq_Userspace:

List of all members.

Public Member Functions
	CPUFreq_Userspace (std::list< int > cpu_cores)
	constructor
	~CPUFreq_Userspace ()
	destructor
bool	init ()
	init cpufreq interface and set userspace governor
Private Member Functions
bool	getMinMaxSpeeds (unsigned long *min, unsigned long *max)
	get the minimum and maximum available speeds
unsigned	getSpeed ()
	get the current CPU speed
int	increaseSpeed ()
	set speed to the next higher supported value
int	decreaseSpeed ()
	set speed to the next lower supported value
bool	setSpeed (unsigned kHz)
	set the current CPU speed
void	setSpeed (unsigned current, unsigned target)
	set the speed smoothly in steps
void	createHysteresisArray ()
	creates the hysteresis array
bool	readFrequencies ()
	reads out frequencies
int	adjustSpeed ()
	adjusts speeds
void	reinitSpeed ()
	reinits speeds
int	initFreqsViaFile ()
	inits the available speeds via reading from file
int	initFreqsViaTesting ()
	inits the available speeds via testing
void	setConfig ()
	set configuration in initialize values
Private Attributes
string	CURRENT_SPEED_FILE
	speed file to get or set current speed
unsigned	_speeds_kHz [MAX_SPEEDS+1]
	array containing available speeds
unsigned	_demotion [MAX_SPEEDS+1]
	demotion
unsigned	_current_speed
	the current set speed
unsigned	_new_speed
	the new speed requested to set
unsigned	_last_step
	the last step set
int	_last_cpu_load
	set last cpu load
string	USERSPACE_STRING
	name of userspace governor to write to governor file

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Detailed Description

Class to control one CPU's frequency by the powersave daemon.

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Constructor & Destructor Documentation

CPUFreq_Userspace::CPUFreq_Userspace (  std::list< int >  cpu_cores  )

constructor Parameters: cpu_cores  stl list containing all cores the object has to care about

CPUFreq_Userspace::~CPUFreq_Userspace (   )

destructor

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Member Function Documentation

int CPUFreq_Userspace::adjustSpeed (   )  [private, virtual]

adjusts speeds Returns: -1 if speed has been decreased 1 if speed has been increased 0 if speed has not been modified Implements CPUFreq_Interface.

void CPUFreq_Userspace::createHysteresisArray (   )  [private]

creates the hysteresis array

int CPUFreq_Userspace::decreaseSpeed (   )  [private]

set speed to the next lower supported value Returns: integer with result of increase speed Return values: 0  if maximum is already reached 1  if new speed could be set -1  if mode is not userspace

bool CPUFreq_Userspace::getMinMaxSpeeds (  unsigned long *  min, unsigned long *  max )  [private]

get the minimum and maximum available speeds This is currently only used by the userspace class to test frequencies if available_frequencies file is not exported by the kernel's low-level driver Parameters: min  value is set to the minimum speed max  value is set to the maximum speed Returns: false if speedstepping is not supported

unsigned CPUFreq_Userspace::getSpeed (   )  [private]

get the current CPU speed Returns: the speed or 0 on error

int CPUFreq_Userspace::increaseSpeed (   )  [private]

set speed to the next higher supported value Returns: integer with result of increase speed Return values: 0  if maximum is already reached 1  if new speed could be set -1  if mode is not userspace

bool CPUFreq_Userspace::init (   )  [virtual]

init cpufreq interface and set userspace governor Returns: true on success, false otherwise Implements CPUFreq_Interface.

int CPUFreq_Userspace::initFreqsViaFile (   )  [private]

inits the available speeds via reading from file Returns: < 0 on error

int CPUFreq_Userspace::initFreqsViaTesting (   )  [private]

inits the available speeds via testing Returns: < 0 on error

bool CPUFreq_Userspace::readFrequencies (   )  [private, virtual]

reads out frequencies Returns: false on error Implements CPUFreq_Interface.

void CPUFreq_Userspace::reinitSpeed (   )  [private, virtual]

reinits speeds function for suspend workaround. after resuming the frequency might have changed and we haven't recognized. This could possibly break old PowerNow! machines, but as far as I know jumping more than one frequency at once is fixed in kernel module for that machines Implements CPUFreq_Interface.

void CPUFreq_Userspace::setConfig (   )  [private, virtual]

set configuration in initialize values Implements CPUFreq_Interface.

void CPUFreq_Userspace::setSpeed (  unsigned  current, unsigned  target )  [private]

set the speed smoothly in steps This code smoothly transitions the CPU speed from 'current' to 'target' instead of jumping directly to the new speed because some AMD Mobile Athlon parts seem to choke on large differentials causing kernel panics. Parameters: current  the current speed target  the target speed

bool CPUFreq_Userspace::setSpeed (  unsigned  kHz  )  [private]

set the current CPU speed Parameters: kHz  the speed in kHz to set Returns: false if speed could not be set

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Member Data Documentation

unsigned CPUFreq_Userspace::_current_speed [private]

the current set speed

unsigned CPUFreq_Userspace::_demotion[MAX_SPEEDS+1] [private]

demotion

int CPUFreq_Userspace::_last_cpu_load [private]

set last cpu load

unsigned CPUFreq_Userspace::_last_step [private]

the last step set

unsigned CPUFreq_Userspace::_new_speed [private]

the new speed requested to set

unsigned CPUFreq_Userspace::_speeds_kHz[MAX_SPEEDS+1] [private]

array containing available speeds

string CPUFreq_Userspace::CURRENT_SPEED_FILE [private]

speed file to get or set current speed

string CPUFreq_Userspace::USERSPACE_STRING [private]

name of userspace governor to write to governor file

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The documentation for this class was generated from the following files:

• /home/hmacht/devel/powersave/daemon/cpufreq_interface.h
• /home/hmacht/devel/powersave/daemon/cpufreq_userspace.cpp

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