static int
apply_step_offset(double offset)
{
struct timeval old_time, new_time;
double err;
LCL_ReadRawTime(&old_time);
UTI_AddDoubleToTimeval(&old_time, -offset, &new_time);
if (PRV_SetTime(&new_time, NULL) < 0) {
DEBUG_LOG(LOGF_SysGeneric, "settimeofday() failed");
return 0;
}
LCL_ReadRawTime(&old_time);
UTI_DiffTimevalsToDouble(&err, &old_time, &new_time);
lcl_InvokeDispersionNotifyHandlers(fabs(err));
return 1;
}
static int
apply_step_offset(double offset)
{
struct timespec old_time, new_time;
struct timeval new_time_tv;
double err;
LCL_ReadRawTime(&old_time);
UTI_AddDoubleToTimespec(&old_time, -offset, &new_time);
UTI_TimespecToTimeval(&new_time, &new_time_tv);
if (PRV_SetTime(&new_time_tv, NULL) < 0) {
DEBUG_LOG("settimeofday() failed");
return 0;
}
LCL_ReadRawTime(&old_time);
err = UTI_DiffTimespecsToDouble(&old_time, &new_time);
lcl_InvokeDispersionNotifyHandlers(fabs(err));
return 1;
}
static void
update_slew(void)
{
struct timespec now, end_of_slew;
double old_slew_freq, total_freq, corr_freq, duration;
/* Remove currently running timeout */
SCH_RemoveTimeout(slew_timeout_id);
LCL_ReadRawTime(&now);
/* Adjust the offset register by achieved slew */
duration = UTI_DiffTimespecsToDouble(&now, &slew_start);
offset_register -= slew_freq * duration;
stop_fastslew(&now);
/* Estimate how long should the next slew take */
if (fabs(offset_register) < MIN_OFFSET_CORRECTION) {
duration = MAX_SLEW_TIMEOUT;
} else {
duration = correction_rate / fabs(offset_register);
if (duration < MIN_SLEW_TIMEOUT)
duration = MIN_SLEW_TIMEOUT;
}
/* Get frequency offset needed to slew the offset in the duration
and clamp it to the allowed maximum */
corr_freq = offset_register / duration;
if (corr_freq < -max_corr_freq)
corr_freq = -max_corr_freq;
else if (corr_freq > max_corr_freq)
corr_freq = max_corr_freq;
/* Let the system driver perform the slew if the requested frequency
offset is too large for the frequency driver */
if (drv_accrue_offset && fabs(corr_freq) >= fastslew_max_rate &&
fabs(offset_register) > fastslew_min_offset) {
start_fastslew();
corr_freq = 0.0;
}
/* Get the new real frequency and clamp it */
total_freq = clamp_freq(base_freq + corr_freq * (1.0e6 - base_freq));
/* Set the new frequency (the actual frequency returned by the call may be
slightly different from the requested frequency due to rounding) */
total_freq = (*drv_set_freq)(total_freq);
/* Compute the new slewing frequency, it's relative to the real frequency to
make the calculation in offset_convert() cheaper */
old_slew_freq = slew_freq;
slew_freq = (total_freq - base_freq) / (1.0e6 - total_freq);
/* Compute the dispersion introduced by changing frequency and add it
to all statistics held at higher levels in the system */
slew_error = fabs((old_slew_freq - slew_freq) * max_freq_change_delay);
if (slew_error >= MIN_OFFSET_CORRECTION)
lcl_InvokeDispersionNotifyHandlers(slew_error);
/* Compute the duration of the slew and clamp it. If the slewing frequency
is zero or has wrong sign (e.g. due to rounding in the frequency driver or
when base_freq is larger than max_freq, or fast slew is active), use the
maximum timeout and try again on the next update. */
if (fabs(offset_register) < MIN_OFFSET_CORRECTION ||
offset_register * slew_freq <= 0.0) {
duration = MAX_SLEW_TIMEOUT;
} else {
duration = offset_register / slew_freq;
if (duration < MIN_SLEW_TIMEOUT)
duration = MIN_SLEW_TIMEOUT;
else if (duration > MAX_SLEW_TIMEOUT)
duration = MAX_SLEW_TIMEOUT;
}
/* Restart timer for the next update */
UTI_AddDoubleToTimespec(&now, duration, &end_of_slew);
slew_timeout_id = SCH_AddTimeout(&end_of_slew, handle_end_of_slew, NULL);
slew_start = now;
DEBUG_LOG("slew offset=%e corr_rate=%e base_freq=%f total_freq=%f slew_freq=%e duration=%f slew_error=%e",
offset_register, correction_rate, base_freq, total_freq, slew_freq,
duration, slew_error);
}
