[Linuxptp-devel] [PATCH] ptp4l: Make UTC offset configurable.

[Viliam Lejcik]

[Miroslav Lichvar]

Currently UTC offset is defined as a constant - CURRENT_UTC_OFFSET, and if
a leap second is added, that constant is no longer valid. Ptp4l was
updated to read the UTC offset from configuration instead.

Good idea.

@@ -681,7 +681,7 @@ static void clock_update_slave(struct clock *c)
if (!(c->tds.flags & PTP_TIMESCALE)) {
pr_warning("foreign master not using PTP timescale");
}
- if (c->tds.currentUtcOffset < CURRENT_UTC_OFFSET) {
+ if (c->tds.currentUtcOffset < config_get_int(c->config, NULL, "utc_offset")) {

Would it make sense to add a new field to the clock structure instead
of calling config_get_int() every time the fallback offset is needed?

+++ b/ptp4l.8
@@ -327,6 +327,10 @@ The default is 0xFFFF.
The domain attribute of the local clock.
The default is 0.
.TP
+.B utc_offset
+The current number of leap seconds.
+The default is 37.

This should probably say it's the offset between TAI and UTC. The
actual number of leap seconds is smaller by 10 and this could be
confusing.

[Viliam Lejcik]

Hi Miroslav, thank you for your review. I updated the patch as suggested. Hopefully it is ok now...

Viliam Lejcik

-----Original Message-----
Sent: 17 January 2017 10:36
To: Lejcik Viliam
Subject: Re: [PATCH] ptp4l: Make UTC offset configurable.

Currently UTC offset is defined as a constant - CURRENT_UTC_OFFSET,
and if a leap second is added, that constant is no longer valid. Ptp4l
was updated to read the UTC offset from configuration instead.

Good idea.

@@ -681,7 +681,7 @@ static void clock_update_slave(struct clock *c)
if (!(c->tds.flags & PTP_TIMESCALE)) {
pr_warning("foreign master not using PTP timescale");
}
- if (c->tds.currentUtcOffset < CURRENT_UTC_OFFSET) {
+ if (c->tds.currentUtcOffset < config_get_int(c->config, NULL,
+"utc_offset")) {

Would it make sense to add a new field to the clock structure instead of calling
config_get_int() every time the fallback offset is needed?

+++ b/ptp4l.8
@@ -327,6 +327,10 @@ The default is 0xFFFF.
The domain attribute of the local clock.
The default is 0.
.TP
+.B utc_offset
+The current number of leap seconds.
+The default is 37.

This should probably say it's the offset between TAI and UTC. The actual number
of leap seconds is smaller by 10 and this could be confusing.
--
Miroslav Lichvar

[Richard Cochran]

Post by Viliam Lejcik
Hi Miroslav, thank you for your review. I updated the patch as suggested. Hopefully it is ok now...

Applied.

Thanks,
Richard