Prometheus metric lint check fails

[karlism]

Hello,

Running promtool check metrics against latest version of ping exporter:

$ curl -s http://exporter:9346/ping?target=example | promtool check metrics
ping_packets_total non-counter metrics should not have "_total" suffix
ping_times_max no help text
ping_times_min no help text

$ promtool --version
promtool, version 2.13.0 (branch: HEAD, revision: 6ea4252299f542669aca11860abc2192bdc7bede)
  build user:       root@f30bdad2c3fd
  build date:       20191004-11:25:34
  go version:       go1.13.1

It is also generally recommended to report time in seconds, instead of milliseconds.