pdcp: add warn_on_drop option

Author: alvasMan

apps/gnb/gnb_appconfig_translators.cpp

@@ -993,7 +993,7 @@ std::map<five_qi_t, srs_cu_up::cu_up_qos_config> srsran::generate_cu_up_qos_conf
 {
   std::map<five_qi_t, srs_cu_up::cu_up_qos_config> out_cfg = {};
   if (config.qos_cfg.empty()) {
-    out_cfg = config_helpers::make_default_cu_up_qos_config_list();
+    out_cfg = config_helpers::make_default_cu_up_qos_config_list(config.cu_up_cfg.warn_on_drop);
     return out_cfg;
   }
 
@@ -1009,6 +1009,7 @@ std::map<five_qi_t, srs_cu_up::cu_up_qos_config> srsran::generate_cu_up_qos_conf
     }
     // Convert PDCP custom config
     pdcp_custom_config& out_pdcp_custom = out_cfg[qos.five_qi].pdcp_custom;
+    out_pdcp_custom.tx.warn_on_drop     = config.cu_up_cfg.warn_on_drop;
 
     // Obtain RLC config parameters from the respective RLC mode
     const auto& du_five_qi = du_qos[qos.five_qi];

include/srsran/cu_up/cu_up_configuration_helpers.h

@@ -18,20 +18,22 @@ namespace srsran {
 namespace config_helpers {
 
 /// Generates default QoS configuration used by gNB CU-UP.
-inline std::map<five_qi_t, srs_cu_up::cu_up_qos_config> make_default_cu_up_qos_config_list()
+inline std::map<five_qi_t, srs_cu_up::cu_up_qos_config> make_default_cu_up_qos_config_list(bool warn_on_drop)
 {
   std::map<five_qi_t, srs_cu_up::cu_up_qos_config> qos_list = {};
   {
     // 5QI=7
     srs_cu_up::cu_up_qos_config cfg{};
     cfg.pdcp_custom = pdcp_custom_config{}; // defaults are configured as member-initialization within the struct
+    cfg.pdcp_custom.tx.warn_on_drop = warn_on_drop;
 
     qos_list[uint_to_five_qi(7)] = cfg;
   }
   {
     // 5QI=9
     srs_cu_up::cu_up_qos_config cfg{};
     cfg.pdcp_custom = pdcp_custom_config{}; // defaults are configured as member-initialization within the struct
+    cfg.pdcp_custom.tx.warn_on_drop = warn_on_drop;
 
     qos_list[uint_to_five_qi(9)] = cfg;
   }

include/srsran/pdcp/pdcp_config.h

@@ -142,6 +142,7 @@ struct pdcp_custom_config_base {
 
 struct pdcp_custom_config_tx : public pdcp_custom_config_base {
   uint16_t rlc_sdu_queue = 4096;
+  bool     warn_on_drop  = false;
 };
 
 struct pdcp_custom_config_rx : public pdcp_custom_config_base {
@@ -376,10 +377,11 @@ struct formatter<srsran::pdcp_custom_config_tx> {
   auto format(srsran::pdcp_custom_config_tx cfg, FormatContext& ctx) -> decltype(std::declval<FormatContext>().out())
   {
     return format_to(ctx.out(),
-                     "count_notify={} count_max={} rlc_sdu_queue={}",
+                     "count_notify={} count_max={} rlc_sdu_queue={} warn_on_drop={}",
                      cfg.max_count.notify,
                      cfg.max_count.hard,
-                     cfg.rlc_sdu_queue);
+                     cfg.rlc_sdu_queue,
+                     cfg.warn_on_drop);
   }
 };
 

lib/pdcp/pdcp_entity_tx.cpp

@@ -33,7 +33,12 @@ void pdcp_entity_tx::handle_sdu(byte_buffer buf)
     return;
   }
   if ((st.tx_next - st.tx_trans) >= cfg.custom.rlc_sdu_queue) {
-    logger.log_info("Dropping SDU to avoid overloading RLC queue. rlc_sdu_queue={} {}", cfg.custom.rlc_sdu_queue, st);
+    if (not cfg.custom.warn_on_drop) {
+      logger.log_info("Dropping SDU to avoid overloading RLC queue. rlc_sdu_queue={} {}", cfg.custom.rlc_sdu_queue, st);
+    } else {
+      logger.log_warning(
+          "Dropping SDU to avoid overloading RLC queue. rlc_sdu_queue={} {}", cfg.custom.rlc_sdu_queue, st);
+    }
     return;
   }
   if ((st.tx_next - st.tx_trans) >= (window_size - 1)) {

tests/unittests/cu_up/cu_up_test.cpp

@@ -117,6 +117,7 @@ class cu_up_test : public ::testing::Test
     cfg.gtpu_pcap                    = &dummy_pcap;
     cfg.net_cfg.n3_bind_port         = 0; // Random free port selected by the OS.
     cfg.n3_cfg.gtpu_reordering_timer = std::chrono::milliseconds(0);
+    cfg.n3_cfg.warn_on_drop          = false;
     cfg.statistics_report_period     = std::chrono::seconds(1);
 
     return cfg;