Athena::AlgorithmTimer Class Reference

Timer that invokes a user callback once the time is reached. More...

#include <AlgorithmTimer.h>

Collaboration diagram for Athena::AlgorithmTimer:

Public Types
enum	AlgorithmTimerConfig { DEFAULT = 0x0, USEREALTIME = 0x1 }
	Configuration flags for AlgorithmTimer. More...
typedef std::function< void()>	callbackFct_t

Public Member Functions
	AlgorithmTimer (unsigned int milliseconds, callbackFct_t callback=NULL, AlgorithmTimerConfig conf=DEFAULT)
	Create AlgorithmTimer instance and start it (unless seconds==0) More...
	~AlgorithmTimer ()
	Destroy and disable the timer. More...
void	start ()
	(Re)start the timer with the last timeout used More...
void	start (unsigned int milliseconds)
	Start the timer. More...
void	start (ScopedTimer &scope)
	Start the timer. More...
unsigned int	stop ()
	Stop the timer and return the time left in [ms]. More...
unsigned int	timeLeft () const
	Returns the time left in milliseconds. More...
unsigned int	timeout () const
	Returns the currently set timeout (in milliseconds) More...
void	SetGDBCoreDumpDetails (unsigned int details)
	set the levelof details for (optional) gdb core dump More...

Protected Attributes
unsigned int	m_timeout
	timeout in milliseconds More...
struct sigevent	m_sigevent
	for signal handler More...
timer_t	m_timerid
	timer ID More...
callbackFct_t	m_onAlarm
	user callback More...
std::atomic_bool	m_active
	flag protecting race condition at stop More...

Private Member Functions
	AlgorithmTimer ()
	no default constructor More...
	AlgorithmTimer (const AlgorithmTimer &)
	no copying allowed More...
AlgorithmTimer &	operator= (const AlgorithmTimer &)
	no copying allowed More...
callbackFct_t	abortJob ()

Private Attributes
unsigned int	m_gdb_details

Friends
void	AlgorithmTimerHandler::onAlarmThread (sigval_t sv)

Detailed Description

Timer that invokes a user callback once the time is reached.

AlgorithmTimer automatically disables itself in its destructor. Create it on the stack and it will therefore disable itself once it runs out of scope. Example:

StatusCode MyAlgorithm::execute()
{
  Athena::AlgorithmTimer(2000, myAlarmHandler);
  // something that takes a long time
}

The overhead of creating a AlgorithmTimer instance is very small. If you are still worried about it, you can re-use the instance by creating it outside the scope and starting/stopping it manually via its start() and stop() method.

To get the best of both worlds you can create the AlgorithmTimer outside the scope and use an even smaller ScopedTimer instance to start the timer. Once the ScopedTimer instance runs out of scope it will disarm the associated AlgorithmTimer.

MyAlgorithm::MyAlgorithm() :
  m_algorithmTimer(0, myAlarmHandler)   // create it in disabled state
{     
}
 
StatusCode MyAlgorithm::execute()
{
  Athena::ScopedTimer alarm(2000);  // two seconds
  m_algorithmTimer.start(alarm);    // this will start the timer
  // something that takes a long time
}

Definition at line 86 of file AlgorithmTimer.h.

Member Typedef Documentation

callbackFct_t

typedef std::function<void()> Athena::AlgorithmTimer::callbackFct_t

Definition at line 101 of file AlgorithmTimer.h.

Member Enumeration Documentation

AlgorithmTimerConfig

enum Athena::AlgorithmTimer::AlgorithmTimerConfig

Configuration flags for AlgorithmTimer.

Enumerator
DEFAULT	default
USEREALTIME	use real time instead of system time

Definition at line 95 of file AlgorithmTimer.h.

      {
        DEFAULT          = 0x0,    
        USEREALTIME      = 0x1,    
      };

Constructor & Destructor Documentation

AlgorithmTimer() [1/3]

AlgorithmTimer::AlgorithmTimer	(	unsigned int	milliseconds,
		callbackFct_t	callback = NULL,
		AlgorithmTimerConfig	conf = DEFAULT
	)

Create AlgorithmTimer instance and start it (unless seconds==0)

Parameters

milliseconds	Time in milliseconds until expiration of the timer (0 = disabled)
callback	User callback to invoke once time is reached
useRealTime	true, if timer should use ral instead od CPU time

Definition at line 55 of file AlgorithmTimer.cxx.

                                              :
  m_timeout (0),
  m_timerid(),
  m_onAlarm(callback),
  m_gdb_details (0)
{
  // prevent valgrind warning
  // new warning popped up, needs new glibc for this, see http://bugs.kde.org/show_bug.cgi?id=124478
  // possibly valgrind will be fixed, eventually.
  std::memset (&m_sigevent, 0, sizeof (m_sigevent));
 
  m_sigevent.sigev_value.sival_ptr = this;
 
  if (m_onAlarm == NULL)
    m_onAlarm = std::bind(&AlgorithmTimer::abortJob,this);
 
  m_sigevent.sigev_notify = SIGEV_THREAD;
  m_sigevent.sigev_signo  = 0;
  m_sigevent.sigev_notify_function = AlgorithmTimerHandler::onAlarmThread;
  m_sigevent.sigev_notify_attributes = NULL;
 
  // Create the timer
  if ( conf & USEREALTIME )
    {
#ifndef __APPLE__
      timer_create(CLOCK_REALTIME, &m_sigevent, &m_timerid);
#endif
    }
  else
    {
      /*
       * can use virtual time only, if defined on this system
       */
#ifndef __APPLE__
#ifdef _POSIX_CPUTIME
      timer_create(_POSIX_CPUTIME, &m_sigevent, &m_timerid);
#else
      timer_create(CLOCK_REALTIME, &m_sigevent, &m_timerid);
      std::cerr << "\nNo _POSIX_CPUTIME defined on this system !\n\n";
      // we could also disable this timer in this case !
      // seconds = 0;
#endif
#endif
    }
  // Start the timer if requested
  if(milliseconds)
    start(milliseconds);
}

~AlgorithmTimer()

AlgorithmTimer::~AlgorithmTimer

(

)

Destroy and disable the timer.

Definition at line 106 of file AlgorithmTimer.cxx.

{
#ifndef __APPLE__
  m_active = false;
  timer_delete(m_timerid);
#endif
}

AlgorithmTimer() [2/3]

Athena::AlgorithmTimer::AlgorithmTimer ( )

private

no default constructor

AlgorithmTimer() [3/3]

Athena::AlgorithmTimer::AlgorithmTimer ( const AlgorithmTimer &  )

private

no copying allowed

Member Function Documentation

abortJob()

AlgorithmTimer::callbackFct_t AlgorithmTimer::abortJob ( )

private

Definition at line 166 of file AlgorithmTimer.cxx.

{
  /*
   * Print stack trace and abort the job.
   */
  std::ostringstream os;
  os << "Timeout ";
  os << " (" << this->timeout() << " msec) reached";
 
  ServiceHandle<ICoreDumpSvc> coreDumpSvc("CoreDumpSvc", "AlgorithmTimer");
  if ( coreDumpSvc.retrieve().isSuccess() )
    {
      coreDumpSvc->setCoreDumpInfo("Reason", os.str());
      std::cerr << coreDumpSvc->dump() << std::endl;
    }
  else
    {
      std::cerr << os.str() << std::endl;
    }
  abort();
}

operator=()

AlgorithmTimer& Athena::AlgorithmTimer::operator= ( const AlgorithmTimer &  )

private

no copying allowed

SetGDBCoreDumpDetails()

void Athena::AlgorithmTimer::SetGDBCoreDumpDetails ( unsigned int  details )

inline

set the levelof details for (optional) gdb core dump

Definition at line 153 of file AlgorithmTimer.h.

    { m_gdb_details = details; };

start() [1/3]

void Athena::AlgorithmTimer::start ( )

inline

(Re)start the timer with the last timeout used

Definition at line 121 of file AlgorithmTimer.h.

{ start(m_timeout); }

start() [2/3]

void AlgorithmTimer::start

(

ScopedTimer &

scope

)

Start the timer.

Parameters

scope

ScopedTimer instance to automatically stop the timer

Definition at line 130 of file AlgorithmTimer.cxx.

{
  scope.m_timer = this;
  start(scope.m_timeout);
}

start() [3/3]

void AlgorithmTimer::start

(

unsigned int

milliseconds

)

Start the timer.

Parameters

milliseconds

Time in milliseconds until expiration

Definition at line 114 of file AlgorithmTimer.cxx.

{
  // Set the timer
  m_timeout = milliseconds;
#ifndef __APPLE__
  itimerspec spec;
  spec.it_value.tv_sec     = int(m_timeout/1000);
  spec.it_value.tv_nsec    = 1000000*(m_timeout%1000);
  spec.it_interval.tv_sec  = 0;
  spec.it_interval.tv_nsec = 0;
 
  m_active = true;
  timer_settime(m_timerid, 0, &spec, NULL);
#endif
}

stop()

unsigned int AlgorithmTimer::stop

(

)

Stop the timer and return the time left in [ms].

Definition at line 136 of file AlgorithmTimer.cxx.

{
  // stop the timer, and retrieve remaining time
#ifndef __APPLE__
  itimerspec spec;
  spec.it_value.tv_sec     = 0;
  spec.it_value.tv_nsec    = 0;
  spec.it_interval.tv_sec  = 0;
  spec.it_interval.tv_nsec = 0;
 
  itimerspec ovalue;
  m_active = false;
  timer_settime(m_timerid, 0, &spec, &ovalue);
  return 1000*ovalue.it_value.tv_sec + int(ovalue.it_value.tv_nsec/1000000);
#else
  return 0;
#endif
}

timeLeft()

unsigned int AlgorithmTimer::timeLeft

(

)

const

Returns the time left in milliseconds.

Definition at line 155 of file AlgorithmTimer.cxx.

{
#ifndef __APPLE__
  itimerspec spec;
  timer_gettime( m_timerid, &spec );
  return 1000*spec.it_value.tv_sec + int(spec.it_value.tv_nsec/1000000);
#else
    return 0;
#endif
}

timeout()

unsigned int Athena::AlgorithmTimer::timeout ( ) const

inline

Returns the currently set timeout (in milliseconds)

Definition at line 148 of file AlgorithmTimer.h.

{ return m_timeout; }

Friends And Related Function Documentation

AlgorithmTimerHandler::onAlarmThread

void AlgorithmTimerHandler::onAlarmThread ( sigval_t  sv )

friend

Member Data Documentation

m_active

std::atomic_bool Athena::AlgorithmTimer::m_active

protected

flag protecting race condition at stop

Definition at line 162 of file AlgorithmTimer.h.

m_gdb_details

unsigned int Athena::AlgorithmTimer::m_gdb_details

private

Definition at line 173 of file AlgorithmTimer.h.

m_onAlarm

callbackFct_t Athena::AlgorithmTimer::m_onAlarm

protected

user callback

Definition at line 161 of file AlgorithmTimer.h.

m_sigevent

struct sigevent Athena::AlgorithmTimer::m_sigevent

protected

for signal handler

Definition at line 158 of file AlgorithmTimer.h.

m_timeout

unsigned int Athena::AlgorithmTimer::m_timeout

protected

timeout in milliseconds

Definition at line 158 of file AlgorithmTimer.h.

m_timerid

timer_t Athena::AlgorithmTimer::m_timerid

protected

timer ID

Definition at line 160 of file AlgorithmTimer.h.

---

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

• AlgorithmTimer.h
• AlgorithmTimer.cxx