minor cleanup: stats type

app/vmm_influxdb_stats.ml

@@ -199,7 +199,7 @@ let rec read_sock_write_tcp c ?fd addr addrtype =
         end else
           let name = string_of_id hdr.Vmm_asn.id in
           let ru = P.encode_ru name ru in
-          let vmm = match vmm with [] -> [] | _ -> [ P.encode_vmm name vmm ] in
+          let vmm = match vmm with None -> [] | Some xs -> [ P.encode_vmm name xs ] in
           let taps = List.map (P.encode_if name) ifs in
           let out = (String.concat ~sep:"\n" (ru :: vmm @ taps)) ^ "\n" in
           Logs.debug (fun m -> m "writing %d via tcp" (String.length out)) ;

src/vmm_asn.ml

@@ -211,37 +211,26 @@ type stats_cmd = [
   | `Stats_add of int * string list
   | `Stats_remove
   | `Stats_subscribe
-  | `Stats_data of rusage * (string * int64) list * ifdata list
+  | `Stats_data of stats
 ]
 
 let pp_stats_cmd ppf = function
   | `Stats_add (pid, taps) -> Fmt.pf ppf "stats add: pid %d taps %a" pid Fmt.(list ~sep:(unit ", ") string) taps
   | `Stats_remove -> Fmt.string ppf "stat remove"
   | `Stats_subscribe -> Fmt.string ppf "stat subscribe"
-  | `Stats_data (ru, vmm, ifs) -> Fmt.pf ppf "stats data: %a %a %a"
-                                    pp_rusage ru
-                                    pp_vmm vmm
-                                    Fmt.(list ~sep:(unit "@.@.") pp_ifdata) ifs
+  | `Stats_data stats -> Fmt.pf ppf "stats data: %a" pp_stats stats
 
 let stats_cmd =
   let f = function
     | `C1 (pid, taps) -> `Stats_add (pid, taps)
     | `C2 () -> `Stats_remove
     | `C3 () -> `Stats_subscribe
-    | `C4 (ru, vmm, ifdata) ->
-      let vmm = match vmm with None -> [] | Some vmm -> vmm
-      and ifdata = match ifdata with None -> [] | Some ifs -> ifs
-      in
-      `Stats_data (ru, vmm, ifdata)
+    | `C4 (ru, ifs, vmm) -> `Stats_data (ru, vmm, ifs)
   and g = function
     | `Stats_add (pid, taps) -> `C1 (pid, taps)
     | `Stats_remove -> `C2 ()
     | `Stats_subscribe -> `C3 ()
-    | `Stats_data (ru, vmm, ifdata) ->
-      let vmm = match vmm with [] -> None | xs -> Some xs
-      and ifs = match ifdata with [] -> None | xs -> Some xs
-      in
-      `C4 (ru, vmm, ifs)
+    | `Stats_data (ru, ifs, vmm) -> `C4 (ru, vmm, ifs)
   in
   Asn.S.map f g @@
   Asn.S.(choice4
@@ -252,12 +241,11 @@ let stats_cmd =
            (explicit 2 null)
            (explicit 3 (sequence3
                           (required ~label:"resource_usage" ru)
-                          (optional ~label:"vmm_stats" @@ explicit 0
+                          (required ~label:"ifdata" (sequence_of ifdata))
+                          (optional ~label:"vmm_stats"
                              (sequence_of (sequence2
                                              (required ~label:"key" utf8_string)
-                                             (required ~label:"value" int64))))
-                          (optional ~label:"ifdata" @@ explicit 1
-                             (sequence_of ifdata)))))
+                                             (required ~label:"value" int64)))))))
 
 let addr =
   Asn.S.(sequence2

src/vmm_asn.mli

@@ -30,7 +30,7 @@ type stats_cmd = [
   | `Stats_add of int * string list
   | `Stats_remove
   | `Stats_subscribe
-  | `Stats_data of rusage * (string * int64) list * ifdata list
+  | `Stats_data of stats
 ]
 
 type log_cmd = [

src/vmm_core.ml

@@ -209,7 +209,9 @@ let pp_rusage ppf r =
   Fmt.pf ppf "utime %Lu.%d stime %Lu.%d maxrss %Lu ixrss %Lu idrss %Lu isrss %Lu minflt %Lu majflt %Lu nswap %Lu inblock %Lu outblock %Lu msgsnd %Lu msgrcv %Lu signals %Lu nvcsw %Lu nivcsw %Lu"
     (fst r.utime) (snd r.utime) (fst r.stime) (snd r.stime) r.maxrss r.ixrss r.idrss r.isrss r.minflt r.majflt r.nswap r.inblock r.outblock r.msgsnd r.msgrcv r.nsignals r.nvcsw r.nivcsw
 
-let pp_vmm ppf vmm =
+
+type vmm_stats = (string * int64) list
+let pp_vmm_stats ppf vmm =
   Fmt.(list ~sep:(unit "@,") (pair ~sep:(unit ": ") string int64)) ppf vmm
 
 type ifdata = {
@@ -237,6 +239,13 @@ let pp_ifdata ppf i =
   Fmt.pf ppf "name %s flags %lX send_length %lu max_send_length %lu send_drops %lu mtu %lu baudrate %Lu input_packets %Lu input_errors %Lu output_packets %Lu output_errors %Lu collisions %Lu input_bytes %Lu output_bytes %Lu input_mcast %Lu output_mcast %Lu input_dropped %Lu output_dropped %Lu"
     i.name i.flags i.send_length i.max_send_length i.send_drops i.mtu i.baudrate i.input_packets i.input_errors i.output_packets i.output_errors i.collisions i.input_bytes i.output_bytes i.input_mcast i.output_mcast i.input_dropped i.output_dropped
 
+type stats = rusage * vmm_stats option * ifdata list
+let pp_stats ppf (ru, vmm, ifs) =
+  Fmt.pf ppf "%a@.%a@.%a"
+    pp_rusage ru
+    Fmt.(option ~none:(unit "no vmm stats") pp_vmm_stats) vmm
+    Fmt.(list ~sep:(unit "@.@.") pp_ifdata) ifs
+
 module Log = struct
   type event =
     [ `Startup

src/vmm_core.mli

@@ -98,7 +98,9 @@ type rusage = {
   nivcsw : int64;
 }
 val pp_rusage : rusage Fmt.t
-val pp_vmm : (string * int64) list Fmt.t
+
+type vmm_stats = (string * int64) list
+val pp_vmm_stats : vmm_stats Fmt.t
 
 type ifdata = {
   name : string;
@@ -122,6 +124,9 @@ type ifdata = {
 }
 val pp_ifdata : ifdata Fmt.t
 
+type stats = rusage * vmm_stats option * ifdata list
+val pp_stats : stats Fmt.t
+
 module Log :
   sig
     type event =

stats/vmm_stats.ml

@@ -112,7 +112,7 @@ let tick t =
             | None -> Logs.err (fun m -> m "failed to get rusage for %d" pid) ; out
             | Some ru' ->
               let stats =
-                let vmm' = match vmm with None -> [] | Some xs -> List.combine !descr xs in
+                let vmm' = match vmm with None -> None | Some xs -> Some (List.combine !descr xs) in
                 ru', vmm', ifd
               in
               List.fold_left (fun out (id, socket) ->