stats: counters data model

This adds a new data model for counters.
Specifying the errors severity and unit.
A later patch will update vpp_get_stats to take advantage of this.
Only the map plugin is updates as an example.

New .api language:
A new "counters" keyword to define counter sets.

counters map {
  none {
    severity info;
    type counter64;
    units "packets";
    description "valid MAP packets";
  };
  bad_protocol {
    severity error;
    type counter64;
    units "packets";
    description "bad protocol";
  };
};

Each counter has 4 keywords. severity, which is one of error, info or warn.
A type, which is one of counter64 or gauge64.
units, which is a text field using units from YANG.

paths {
  "/err/ip4-map" "map";
  "/err/ip6-map" "map";
  "/err/ip4-t-map" "map";
  "/err/ip6-t-map" "map";
};

A new paths keyword that maps the counter-set to a path in the stats segment KV store.

Updated VPP CLI to include severity so user can see error counter severity.
DBGvpp# show errors
   Count               Node                    Reason        Severity
        13        ethernet-input              no error         error

Type: feature
Signed-off-by: Ole Troan <ot@cisco.com>
Change-Id: Ib2177543f49d4c3aef4d7fa72476cff2068f7771
Signed-off-by: Ole Troan <ot@cisco.com>

1 files changed, 18 insertions, 3 deletions

diff --git a/src/vlib/error.h b/src/vlib/error.h
index 0da3a18d85d..11757e05f67 100644
--- a/src/vlib/error.h
+++ b/src/vlib/error.h
@@ -42,6 +42,20 @@
 
 typedef u16 vlib_error_t;
 
+enum vl_counter_severity_e
+{
+  VL_COUNTER_SEVERITY_ERROR,
+  VL_COUNTER_SEVERITY_WARN,
+  VL_COUNTER_SEVERITY_INFO,
+};
+
+typedef struct
+{
+  char *name;
+  char *desc;
+  enum vl_counter_severity_e severity;
+} vl_counter_t;
+
 typedef struct
 {
   /* Error counters. */
@@ -50,15 +64,16 @@ typedef struct
   /* Counter values as of last counter clear. */
   u64 *counters_last_clear;
 
-  /* Error name strings in heap.  Heap index
+  /* Counter structures in heap. Heap index
      indexes counter vector. */
-  char **error_strings_heap;
+  vl_counter_t *counters_heap;
 } vlib_error_main_t;
 
 /* Per node error registration. */
 void vlib_register_errors (struct vlib_main_t *vm,
 			   u32 node_index,
-			   u32 n_errors, char *error_strings[]);
+			   u32 n_errors, char *error_strings[],
+			   vl_counter_t counters[]);
 
 #endif /* included_vlib_error_h */