FLA_Clock.c File Reference

(r)

Functions
double	FLA_Clock_helper (void)
double	FLA_Clock ()
void	detect_clocks (void)
void	rdtsc (unsigned int *high, unsigned int *low)
Variables
double	gtod_ref_time_sec = 0.0

---

Function Documentation

void detect_clocks

(

void

)

References rdtsc().

{
  FILE *infile;
  char buffer[256], *p;
#ifdef __i386__
  unsigned int high, low;
#endif

  if ( clocks == 0.0 )
  {
    p = (char *)NULL;
    infile = fopen("/proc/cpuinfo", "r");
    while (fgets(buffer, sizeof(buffer), infile))
    {
      if (!strncmp("cpu MHz", buffer, 6))
      {
        p = strchr(buffer, ':') + 1;
        break;
      }
    }
    clocks = 1.e6 * atof(p);
#ifdef __i386__
    rdtsc(&high, &low);
    initialclockoffset = high;
#endif
  }
}

double FLA_Clock

(

void

)

References FLA_Clock_helper().

Referenced by FLASH_Queue_begin(), FLASH_Queue_end(), and FLASH_Queue_exec().

{
  return FLA_Clock_helper();
}

double FLA_Clock_helper

(

void

)

References gtod_ref_time_sec.

Referenced by FLA_Clock().

{
#ifdef FLA_ENABLE_TIDSP
  double the_time;
  the_time = 0.0;
#else
#ifdef FLA_PORTABLE_TIMER_IS_CLOCK_GETTIME
  double          the_time, norm_sec;
  struct timespec tsp;

  clock_gettime( CLOCK_REALTIME, &tsp );

  // If this is the first invocation of through FLA_Clock(), then initialize
  // the "reference time" global variable to the seconds field of the tv
  // struct.
  if ( gtod_ref_time_sec == 0.0 ) gtod_ref_time_sec = ( double ) tsp.tv_sec;

  // Normalize the seconds field of the tv struct so that it is relative to the
  // "reference time" that was recorded during the first invocation of
  // FLA_Clock().
  norm_sec = ( double ) tsp.tv_sec - gtod_ref_time_sec;

  // Compute the number of seconds since the reference time.
  the_time = norm_sec + tsp.tv_nsec * 1.0e-9;

#else
#ifdef FLA_PORTABLE_TIMER_IS_GETTIMEOFDAY
  
  double         the_time, norm_sec;
  struct timeval tv;

  gettimeofday( &tv, NULL );

  // If this is the first invocation of through FLA_Clock(), then initialize
  // the "reference time" global variable to the seconds field of the tv
  // struct.
  if ( gtod_ref_time_sec == 0.0 ) gtod_ref_time_sec = ( double ) tv.tv_sec;

  // Normalize the seconds field of the tv struct so that it is relative to the
  // "reference time" that was recorded during the first invocation of
  // FLA_Clock().
  norm_sec = ( double ) tv.tv_sec - gtod_ref_time_sec;

  // Compute the number of seconds since the reference time.
  the_time = norm_sec + tv.tv_usec * 1.0e-6;

#else //#ifdef FLA_PORTABLE_TIMER_IS_UNKNOWN

  the_time = 0.0;

#endif
#endif
#endif

  return the_time;
}

void rdtsc	(	unsigned int *	high,
		unsigned int *	low
	)		[inline]

Referenced by detect_clocks().

{
  asm("rdtsc" : "=a" (*low), "=d"(*high): : "cc");
}

---

Variable Documentation

double gtod_ref_time_sec = 0.0

Referenced by FLA_Clock_helper().