cmdmon: add timestamp counters to serverstats report

Add the new RX/TX daemon/kernel/hardware timestamp counters to the
serverstats report.

doc/chrony.conf.adoc

@@ -2536,10 +2536,13 @@ physical clock created by writing to _/sys/class/ptp/ptpX/n_vclocks_. This
 feature is available on Linux 5.14 and newer.
 +
 If the kernel supports software timestamping, it will be enabled for all
-interfaces. The source of timestamps (i.e. hardware, kernel, or daemon) is
-indicated in the _measurements.log_ file if enabled by the <<log,*log
-measurements*>> directive, and the <<chronyc.adoc#ntpdata,*ntpdata*>> report in
-*chronyc*.
+interfaces automatically.
++
+The source of timestamps (i.e. hardware, kernel, or daemon) is indicated on the
+client side in the _measurements.log_ file (if enabled by the <<log,*log*>>
+directive) and the <<chronyc.adoc#ntpdata,*ntpdata*>> report. On the server
+side, the number of served timestamps from each source is provided in the
+<<chronyc.adoc#serverstats,*serverstats*>> report.
 +
 This directive can be used multiple times to enable HW timestamping on multiple
 interfaces. If the specified interface is _*_, *chronyd* will try to enable HW

doc/chronyc.adoc

@@ -1158,6 +1158,12 @@ Authenticated NTP packets  : 189
 Interleaved NTP packets    : 43
 NTP timestamps held        : 44
 NTP timestamp span         : 120
+NTP daemon RX timestamps   : 0
+NTP daemon TX timestamps   : 1537
+NTP kernel RX timestamps   : 1590
+NTP kernel TX timestamps   : 43
+NTP hardware RX timestamps : 0
+NTP hardware TX timestamps : 0
 ----
 +
 The fields have the following meaning:
@@ -1192,6 +1198,24 @@ The number of pairs of receive and transmit timestamps that the server is
 currently holding in memory for clients using the interleaved mode.
 *NTP timestamp span*:::
 The interval (in seconds) covered by the currently held NTP timestamps.
+*NTP daemon RX timestamps*:::
+The number of NTP responses which included a receive timestamp captured by the
+daemon.
+*NTP daemon TX timestamps*:::
+The number of NTP responses which included a transmit timestamp captured by the
+daemon.
+*NTP kernel RX timestamps*:::
+The number of NTP responses which included a receive timestamp captured by the
+kernel.
+*NTP kernel TX timestamps*:::
+The number of NTP responses (in the interleaved mode) which included a transmit
+timestamp captured by the kernel.
+*NTP hardware RX timestamps*:::
+The number of NTP responses which included a receive timestamp captured by the
+NIC.
+*NTP hardware TX timestamps*:::
+The number of NTP responses (in the interleaved mode) which included a transmit
+timestamp captured by the NIC.
 {blank}::
 +
 Note that the numbers reported by this command overflow to zero after