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Commit 6a33f66e authored by Alessandro Rubini's avatar Alessandro Rubini
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general: rename oneWayDelay to meanPathDelay 

The 1588 standard talks extensively about "mean path delay"
and the meanPathDelay variable.   Even if the name is not the
best one, we'd better rename the fields and variable.

This is a massive change, but the currenct code has been validated at
the Lemgo plug fest, and I don't expect any need to revert older
patches at this point.  I'm sorry for git-blame users, including myself,
but this change is a step forward.  I should have knonw better when
choosing "one way delay" between the two names of the older code.

Thanks to Aurelio for noting the problem.
Signed-off-by: Alessandro Rubini's avatarAlessandro Rubini <rubini@gnudd.com>
parent 1d1531bc
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Showing with 38 additions and 38 deletions
include/ppsi/ieee1588_types.h
View file @ 6a33f66e
......@@ -231,7 +231,7 @@ typedef struct DSCurrent { /* page 67 */
/* Dynamic */
UInteger16 stepsRemoved;
TimeInternal offsetFromMaster;
TimeInternal oneWayDelay;
TimeInternal meanPathDelay; /* oneWayDelay */
/* White Rabbit extension begin */
UInteger16 primarySlavePortNumber;
/* White Rabbit extension end */
......
include/ppsi/pp-instance.h
View file @ 6a33f66e
......@@ -86,7 +86,7 @@ struct pp_servo {
TimeInternal m_to_s_dly;
TimeInternal s_to_m_dly;
Integer32 obs_drift;
struct pp_avg_fltr owd_fltr;
struct pp_avg_fltr mpd_fltr;
struct pp_avg_fltr ofm_fltr;
};
......
proto-standard/bmc.c
View file @ 6a33f66e
......@@ -25,7 +25,7 @@ void m1(struct pp_instance *ppi)
/* Current data set update */
DSCUR(ppi)->stepsRemoved = 0;
clear_TimeInternal(&DSCUR(ppi)->offsetFromMaster);
clear_TimeInternal(&DSCUR(ppi)->oneWayDelay);
clear_TimeInternal(&DSCUR(ppi)->meanPathDelay);
/* Parent data set: we are the parent */
memset(parent, 0, sizeof(*parent));
......
proto-standard/servo.c
View file @ 6a33f66e
......@@ -12,7 +12,7 @@ void pp_servo_init(struct pp_instance *ppi)
{
int d;
SRV(ppi)->owd_fltr.s_exp = 0; /* clears one-way delay filter */
SRV(ppi)->mpd_fltr.s_exp = 0; /* clears one-way delay filter */
SRV(ppi)->ofm_fltr.s_exp = 0; /* clears offset-from-master filter */
......@@ -65,16 +65,16 @@ void pp_servo_got_sync(struct pp_instance *ppi)
/*
* This function makes the necessary checks to discard a set of t1..t4.
* It relies on owd to be already calculated.
* It relies on mpd to be already calculated.
*/
static int pp_servo_bad_event(struct pp_instance *ppi)
{
TimeInternal *m_to_s_dly = &SRV(ppi)->m_to_s_dly;
TimeInternal *s_to_m_dly = &SRV(ppi)->s_to_m_dly;
TimeInternal *owd = &DSCUR(ppi)->oneWayDelay;
TimeInternal *mpd = &DSCUR(ppi)->meanPathDelay;
/* Discard one-way delays that overflow a second (makes no sense) */
if (owd->seconds)
if (mpd->seconds)
return 1;
if (OPTS(ppi)->max_dly) { /* If maxDelay is 0 then it's OFF */
......@@ -102,9 +102,9 @@ void pp_servo_got_resp(struct pp_instance *ppi)
{
TimeInternal *m_to_s_dly = &SRV(ppi)->m_to_s_dly;
TimeInternal *s_to_m_dly = &SRV(ppi)->s_to_m_dly;
TimeInternal *owd = &DSCUR(ppi)->oneWayDelay;
TimeInternal *mpd = &DSCUR(ppi)->meanPathDelay;
TimeInternal *ofm = &DSCUR(ppi)->offsetFromMaster;
struct pp_avg_fltr *owd_fltr = &SRV(ppi)->owd_fltr;
struct pp_avg_fltr *mpd_fltr = &SRV(ppi)->mpd_fltr;
struct pp_avg_fltr *ofm_fltr = &SRV(ppi)->ofm_fltr;
Integer32 adj;
int s;
......@@ -126,63 +126,63 @@ void pp_servo_got_resp(struct pp_instance *ppi)
pp_diag(ppi, servo, 1, "Slave to master: %s\n", fmt_TI(s_to_m_dly));
/* Calc mean path delay, used later to calc "offset from master" */
add_TimeInternal(owd, &SRV(ppi)->m_to_s_dly, &SRV(ppi)->s_to_m_dly);
div2_TimeInternal(owd);
pp_diag(ppi, servo, 1, "One-way delay: %s\n", fmt_TI(owd));
add_TimeInternal(mpd, &SRV(ppi)->m_to_s_dly, &SRV(ppi)->s_to_m_dly);
div2_TimeInternal(mpd);
pp_diag(ppi, servo, 1, "One-way delay: %s\n", fmt_TI(mpd));
if(pp_servo_bad_event(ppi))
return;
if (owd_fltr->s_exp < 1) {
if (mpd_fltr->s_exp < 1) {
/* First time, keep what we have */
owd_fltr->y = owd->nanoseconds;
mpd_fltr->y = mpd->nanoseconds;
}
/* avoid overflowing filter */
s = OPTS(ppi)->s;
while (abs(owd_fltr->y) >> (31 - s))
while (abs(mpd_fltr->y) >> (31 - s))
--s;
if (owd_fltr->s_exp > 1 << s)
owd_fltr->s_exp = 1 << s;
if (mpd_fltr->s_exp > 1 << s)
mpd_fltr->s_exp = 1 << s;
/* crank down filter cutoff by increasing 's_exp' */
if (owd_fltr->s_exp < 1 << s)
++owd_fltr->s_exp;
if (mpd_fltr->s_exp < 1 << s)
++mpd_fltr->s_exp;
/*
* It may happen that owd appears as negative. This happens when
* It may happen that mpd appears as negative. This happens when
* the slave clock is running fast to recover a late time: the
* (t3 - t2) measured in the slave appears longer than the (t4 - t1)
* measured in the master. Ignore such values, by keeping the
* current average instead.
*/
if (owd->nanoseconds < 0)
owd->nanoseconds = owd_fltr->y;
if (owd->nanoseconds < 0)
owd->nanoseconds = 0;
if (mpd->nanoseconds < 0)
mpd->nanoseconds = mpd_fltr->y;
if (mpd->nanoseconds < 0)
mpd->nanoseconds = 0;
/*
* It may happen that owd appears to be very big. This happens
* It may happen that mpd appears to be very big. This happens
* when we have software timestamps and there is overhead
* involved -- or when the slave clock is running slow. In
* this case use a value just slightly bigger than the current
* average (so if it really got longer, we will adapt). This
* kills most outliers on loaded networks.
*/
if (owd->nanoseconds > 3 * owd_fltr->y) {
pp_diag(ppi, servo, 1, "Trim too-long owd: %i\n",
owd->nanoseconds);
if (mpd->nanoseconds > 3 * mpd_fltr->y) {
pp_diag(ppi, servo, 1, "Trim too-long mpd: %i\n",
mpd->nanoseconds);
/* add fltr->s_exp to ensure we are not trapped into 0 */
owd->nanoseconds = owd_fltr->y * 2 + owd_fltr->s_exp + 1;
mpd->nanoseconds = mpd_fltr->y * 2 + mpd_fltr->s_exp + 1;
}
/* filter 'oneWayDelay' (running average) */
owd_fltr->y = (owd_fltr->y * (owd_fltr->s_exp - 1) + owd->nanoseconds)
/ owd_fltr->s_exp;
owd->nanoseconds = owd_fltr->y;
/* filter 'meanPathDelay' (running average) */
mpd_fltr->y = (mpd_fltr->y * (mpd_fltr->s_exp - 1) + mpd->nanoseconds)
/ mpd_fltr->s_exp;
mpd->nanoseconds = mpd_fltr->y;
pp_diag(ppi, servo, 1, "After avg(%i), one-way delay: %i\n",
(int)owd_fltr->s_exp, owd->nanoseconds);
(int)mpd_fltr->s_exp, mpd->nanoseconds);
/* update 'offsetFromMaster', (End to End mode) */
sub_TimeInternal(ofm, m_to_s_dly, owd);
sub_TimeInternal(ofm, m_to_s_dly, mpd);
pp_diag(ppi, servo, 2, "Offset from master: %s\n", fmt_TI(ofm));
if (OPTS(ppi)->max_rst) { /* If max_rst is 0 then it's OFF */
......@@ -209,7 +209,7 @@ void pp_servo_got_resp(struct pp_instance *ppi)
/* Can't use "adjust, limited to +/- 2s */
time_tmp = ppi->t4;
add_TimeInternal(&time_tmp, &time_tmp,
&DSCUR(ppi)->oneWayDelay);
&DSCUR(ppi)->meanPathDelay);
ppi->t_ops->set(ppi, &time_tmp);
pp_servo_init(ppi);
} else {
......@@ -226,7 +226,7 @@ void pp_servo_got_resp(struct pp_instance *ppi)
}
/*
* Filter the ofm using the same running averags as we used for owd
* Filter the ofm using the same running averags as we used for mpd
*/
if (ofm_fltr->s_exp < 1) {
/* First time, keep what we have */
......@@ -328,7 +328,7 @@ void pp_servo_got_resp(struct pp_instance *ppi)
ppi->t_ops->adjust_offset(ppi, -adj);
}
pp_diag(ppi, servo, 2, "One-way delay averaged: %s\n", fmt_TI(owd));
pp_diag(ppi, servo, 2, "One-way delay averaged: %s\n", fmt_TI(mpd));
pp_diag(ppi, servo, 2, "Offset from m averaged: %s\n", fmt_TI(ofm));
pp_diag(ppi, servo, 2, "Observed drift: %9i\n",
(int)SRV(ppi)->obs_drift);
......
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