nr rlc stats: make avg time to tx optional

Introduce the function nr_rlc_activate_avg_time_to_tx() to
activate/deactivate collection of avg time to tx stats (which
may have an impact on realtime processing, so better not compute
them when not needed).

Fix a little bug in time_average_get_average() for when there is not stat.

common/utils/time_stat.c

@@ -61,6 +61,14 @@ void time_average_free(time_average_t *t)
   free(t);
 }
 
+void time_average_reset(time_average_t *t)
+{
+  t->r.head = t->r.maxsize - 1;
+  t->r.tail = 0;
+  t->r.size = 0;
+  t->accumulated_value = 0;
+}
+
 static void remove_old(time_average_t *t, uint64_t time)
 {
   /* remove old events */
@@ -103,6 +111,9 @@ double time_average_get_average(time_average_t *t, uint64_t time)
 {
   remove_old(t, time);
 
+  if (t->r.size == 0)
+    return 0;
+
   return (double)t->accumulated_value / t->r.size;
 }
 

common/utils/time_stat.h

@@ -46,6 +46,7 @@ typedef struct {
 /* 'duration' is in unit microsecond */
 time_average_t *time_average_new(int duration, int initial_size);
 void time_average_free(time_average_t *t);
+void time_average_reset(time_average_t *t);
 
 /* add a value tagged with time 'time' unit microsecond (it also modifies 't',
  * removing all data with time < 'time' - t->duration)

openair2/LAYER2/nr_rlc/nr_rlc_entity.c

@@ -37,8 +37,11 @@ static void nr_rlc_entity_get_stats(
 {
 // printf("Stats from the RLC entity asked\n");
   *out = entity->stats;
-  out->txsdu_avg_time_to_tx = time_average_get_average(entity->txsdu_avg_time_to_tx,
-                                  time_average_now());
+  if (entity->avg_time_is_on)
+    out->txsdu_avg_time_to_tx = time_average_get_average(entity->txsdu_avg_time_to_tx,
+                                    time_average_now());
+  else
+    out->txsdu_avg_time_to_tx = 0;
 }
 
 nr_rlc_entity_t *new_nr_rlc_entity_am(

openair2/LAYER2/nr_rlc/nr_rlc_entity.h

@@ -137,6 +137,7 @@ typedef struct nr_rlc_entity_t {
 
   nr_rlc_statistics_t stats;
   time_average_t *txsdu_avg_time_to_tx;
+  int             avg_time_is_on;
 } nr_rlc_entity_t;
 
 nr_rlc_entity_t *new_nr_rlc_entity_am(

openair2/LAYER2/nr_rlc/nr_rlc_entity_am.c

@@ -1718,7 +1718,8 @@ void nr_rlc_entity_am_recv_sdu(nr_rlc_entity_t *_entity,
   entity->common.bstatus.tx_size += compute_pdu_header_size(entity, sdu)
                                     + sdu->size;
 
-  sdu->sdu->time_of_arrival = time_average_now();
+  if (entity->common.avg_time_is_on)
+    sdu->sdu->time_of_arrival = time_average_now();
 }
 
 /*************************************************************************/

openair2/LAYER2/nr_rlc/nr_rlc_entity_tm.c

@@ -155,7 +155,8 @@ void nr_rlc_entity_tm_recv_sdu(nr_rlc_entity_t *_entity,
   /* update buffer status */
   entity->common.bstatus.tx_size += sdu->size;
 
-  sdu->sdu->time_of_arrival = time_average_now();
+  if (entity->common.avg_time_is_on)
+    sdu->sdu->time_of_arrival = time_average_now();
 }
 
 /*************************************************************************/

openair2/LAYER2/nr_rlc/nr_rlc_entity_um.c

@@ -595,7 +595,8 @@ void nr_rlc_entity_um_recv_sdu(nr_rlc_entity_t *_entity,
   entity->common.bstatus.tx_size += compute_pdu_header_size(entity, sdu)
                                     + sdu->size;
 
-  sdu->sdu->time_of_arrival = time_average_now();
+  if (entity->common.avg_time_is_on)
+    sdu->sdu->time_of_arrival = time_average_now();
 }
 
 /*************************************************************************/

openair2/LAYER2/nr_rlc/nr_rlc_oai_api.c

@@ -1111,6 +1111,33 @@ void rlc_tick(int a, int b)
   exit(1);
 }
 
+void nr_rlc_activate_avg_time_to_tx(
+  const rnti_t            rnti,
+  const logical_chan_id_t channel_id,
+  const bool              is_on)
+{
+  nr_rlc_ue_t *ue;
+  nr_rlc_entity_t *rb;
+
+  nr_rlc_manager_lock(nr_rlc_ue_manager);
+  ue = nr_rlc_manager_get_ue(nr_rlc_ue_manager, rnti);
+
+  switch (channel_id) {
+  case 1 ... 3: rb = ue->srb[channel_id - 1]; break;
+  case 4 ... 8: rb = ue->drb[channel_id - 4]; break;
+  default:      rb = NULL;                    break;
+  }
+
+  if (rb != NULL) {
+    rb->avg_time_is_on = is_on;
+    time_average_reset(rb->txsdu_avg_time_to_tx);
+  } else {
+    LOG_E(RLC, "[%s] Radio Bearer (channel ID %d) is NULL for UE with rnti %x\n", __FUNCTION__, channel_id, rnti);
+  }
+
+  nr_rlc_manager_unlock(nr_rlc_ue_manager);
+}
+
 /* returns 0 in case of error, 1 if everything ok */
 int const nr_rlc_get_statistics(
   int rnti,

openair2/LAYER2/nr_rlc/nr_rlc_oai_api.h

@@ -51,3 +51,8 @@ void nr_rlc_bearer_init_ul_spec(struct NR_LogicalChannelConfig *mac_LogicalChann
 int nr_rlc_get_available_tx_space(
   const rnti_t            rntiP,
   const logical_chan_id_t channel_idP);
+
+void nr_rlc_activate_avg_time_to_tx(
+  const rnti_t            rnti,
+  const logical_chan_id_t channel_id,
+  const bool              is_on);