relay: Add CC RTT reset stats to MetricsPort

Related to #40194

Signed-off-by: David Goulet <dgoulet@torproject.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/src/feature/relay/relay_metrics.c b/src/feature/relay/relay_metrics.c
index e48e211ba7..77ccaac722 100644
--- a/src/feature/relay/relay_metrics.c
+++ b/src/feature/relay/relay_metrics.c
@@ -12,6 +12,7 @@
 
 #include "core/or/or.h"
 #include "core/mainloop/connection.h"
+#include "core/or/congestion_control_common.h"
 #include "core/or/relay.h"
 
 #include "lib/malloc/malloc.h"
@@ -25,6 +26,7 @@
 #include <event2/dns.h>
 
 /** Declarations of each fill function for metrics defined in base_metrics. */
+static void fill_cc_values(void);
 static void fill_connections_values(void);
 static void fill_dns_error_values(void);
 static void fill_dns_query_values(void);
@@ -104,6 +106,13 @@ static const relay_metrics_entry_t base_metrics[] =
     .help = "Total number of streams",
     .fill_fn = fill_streams_values,
   },
+  {
+    .key = RELAY_METRICS_NUM_CC,
+    .type = METRICS_TYPE_COUNTER,
+    .name = METRICS_NAME(relay_congestion_control_total),
+    .help = "Congestion control related counters",
+    .fill_fn = fill_cc_values,
+  },
 };
 static const size_t num_base_metrics = ARRAY_LENGTH(base_metrics);
 
@@ -130,6 +139,21 @@ handshake_type_to_str(const uint16_t type)
   }
 }
 
+/** Fill function for the RELAY_METRICS_NUM_CC metric. */
+static void
+fill_cc_values(void)
+{
+  const relay_metrics_entry_t *rentry = &base_metrics[RELAY_METRICS_NUM_CC];
+  metrics_store_entry_t *sentry =
+    metrics_store_add(the_store, rentry->type, rentry->name, rentry->help);
+
+  metrics_store_entry_add_label(sentry,
+          metrics_format_label("state", "starvation"));
+  metrics_store_entry_add_label(sentry,
+          metrics_format_label("action", "rtt_reset"));
+  metrics_store_entry_update(sentry, congestion_control_get_num_rtt_reset());
+}
+
 /** Helper: Fill in single stream metrics output. */
 static void
 fill_single_stream_value(metrics_store_entry_t *sentry, uint8_t cmd)