s1ap_proxy: improve per-eNB counter reg/inc API

Change-Id: I2244190d0640209f8a2d4d78e5b64db580aa863d
---
M src/s1ap_proxy.erl
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/s1ap_proxy.erl b/src/s1ap_proxy.erl
index 0903906..a29a817 100644
--- a/src/s1ap_proxy.erl
+++ b/src/s1ap_proxy.erl
@@ -212,7 +212,7 @@
 
 %% register a single per-eNB counter
 -spec ctr_reg(C, GlobalENBId) -> C
-    when C :: [ctr | _],
+    when C :: s1gw_metrics:counter(),
          GlobalENBId :: string().
 ctr_reg([ctr, s1ap, proxy | _] = C0, GlobalENBId) ->
     C1 = s1gw_metrics:enb_metric(C0, GlobalENBId),
@@ -232,9 +232,9 @@
 
 %% increment the global and/or per-eNB counters
 -spec ctr_inc(C0, S) -> term()
-    when C0 :: [ctr | _],
+    when C0 :: s1gw_metrics:counter(),
          S :: proxy_state().
-ctr_inc([ctr | _] = C0, S) ->
+ctr_inc([ctr, s1ap, proxy | _] = C0, S) ->
     case S#proxy_state.genb_id_str of
         undefined ->
             %% increment the global counter only

