cu_cp_unit: added a CU-CP wrapper to store objects related to the CU-CP. Moved the n2 clients to this wrapper and removed them from the gNB and CU applications

Author: AlaiaL

apps/cu/cu.cpp

@@ -313,18 +313,8 @@ int main(int argc, char** argv)
   cu_cp_dependencies.cu_cp_executor = workers.cu_cp_exec;
   cu_cp_dependencies.cu_cp_e2_exec  = workers.cu_cp_e2_exec;
   cu_cp_dependencies.timers         = cu_timers;
-
-  // Create N2 Client Gateways.
-  cu_cp_dependencies.n2_clients.push_back(srs_cu_cp::create_n2_connection_client(
-      generate_n2_client_config(cu_cp_app_unit->get_cu_cp_unit_config().amf_config.no_core,
-                                cu_cp_app_unit->get_cu_cp_unit_config().amf_config.amf,
-                                *cu_cp_dlt_pcaps.ngap,
-                                *epoll_broker)));
-
-  for (const auto& amf : cu_cp_app_unit->get_cu_cp_unit_config().extra_amfs) {
-    cu_cp_dependencies.n2_clients.push_back(srs_cu_cp::create_n2_connection_client(generate_n2_client_config(
-        cu_cp_app_unit->get_cu_cp_unit_config().amf_config.no_core, amf, *cu_cp_dlt_pcaps.ngap, *epoll_broker)));
-  }
+  cu_cp_dependencies.ngap_pcap      = cu_cp_dlt_pcaps.ngap.get();
+  cu_cp_dependencies.broker         = epoll_broker.get();
 
   // create CU-CP.
   auto              cu_cp_obj_and_cmds = cu_cp_app_unit->create_cu_cp(cu_cp_dependencies);

apps/gnb/gnb.cpp

@@ -360,12 +360,6 @@ int main(int argc, char** argv)
 
   e2_metric_connector_manager e2_metric_connectors(du_app_unit->get_du_high_unit_config().cells_cfg.size());
 
-  // Create CU-CP config.
-  cu_cp_build_dependencies cu_cp_dependencies;
-  cu_cp_dependencies.cu_cp_executor = workers.cu_cp_exec;
-  cu_cp_dependencies.cu_cp_e2_exec  = workers.cu_cp_e2_exec;
-  cu_cp_dependencies.timers         = cu_timers;
-
   // Load CU-CP plugins if enabled
   std::optional<dynlink_manager> ng_handover_plugin =
       cu_cp_app_unit->get_cu_cp_unit_config().load_plugins
@@ -404,23 +398,13 @@ int main(int argc, char** argv)
     cu_cp_app_unit->get_cu_cp_unit_config().disconnect_amfs_func_ptr = disconnect_amfs.value();
   }
 
-  // Create N2 Client Gateways.
-  cu_cp_dependencies.n2_clients.push_back(srs_cu_cp::create_n2_connection_client(
-      generate_n2_client_config(cu_cp_app_unit->get_cu_cp_unit_config().amf_config.no_core,
-                                cu_cp_app_unit->get_cu_cp_unit_config().amf_config.amf,
-                                *cu_cp_dlt_pcaps.ngap,
-                                *epoll_broker)));
-
-  for (const auto& amf : cu_cp_app_unit->get_cu_cp_unit_config().extra_amfs) {
-    cu_cp_dependencies.n2_clients.push_back(srs_cu_cp::create_n2_connection_client(generate_n2_client_config(
-        cu_cp_app_unit->get_cu_cp_unit_config().amf_config.no_core, amf, *cu_cp_dlt_pcaps.ngap, *epoll_broker)));
-  }
-
-  // E2AP configuration.
-  srsran::sctp_network_connector_config e2_du_nw_config = generate_e2ap_nw_config(gnb_cfg, E2_DU_PPID);
-
-  // Create E2AP GW remote connector.
-  e2_gateway_remote_connector e2_gw{*epoll_broker, e2_du_nw_config, *du_pcaps.e2ap};
+  // Create CU-CP dependencies.
+  cu_cp_build_dependencies cu_cp_dependencies;
+  cu_cp_dependencies.cu_cp_executor = workers.cu_cp_exec;
+  cu_cp_dependencies.cu_cp_e2_exec  = workers.cu_cp_e2_exec;
+  cu_cp_dependencies.timers         = cu_timers;
+  cu_cp_dependencies.ngap_pcap      = cu_cp_dlt_pcaps.ngap.get();
+  cu_cp_dependencies.broker         = epoll_broker.get();
 
   // create CU-CP.
   auto cu_cp_obj_and_cmds = cu_cp_app_unit->create_cu_cp(cu_cp_dependencies);
@@ -438,6 +422,12 @@ int main(int argc, char** argv)
 
   std::unique_ptr<srs_cu_up::cu_up_interface> cu_up_obj = cu_up_app_unit->create_cu_up_unit(cu_up_unit_deps);
 
+  // E2AP configuration.
+  sctp_network_connector_config e2_du_nw_config = generate_e2ap_nw_config(gnb_cfg, E2_DU_PPID);
+
+  // Create E2AP GW remote connector.
+  e2_gateway_remote_connector e2_gw{*epoll_broker, e2_du_nw_config, *du_pcaps.e2ap};
+
   // Instantiate one DU.
   app_services::metrics_notifier_proxy_impl metrics_notifier_forwarder;
   du_unit_dependencies                      du_dependencies;

apps/units/cu_cp/CMakeLists.txt

@@ -12,7 +12,8 @@ set(SOURCES
         cu_cp_unit_config_cli11_schema.cpp
         cu_cp_config_translators.cpp
         cu_cp_unit_config_validator.cpp
-        cu_cp_unit_config_yaml_writer.cpp)
+        cu_cp_unit_config_yaml_writer.cpp
+        cu_cp_wrapper.cpp)
 
 add_library(srsran_cu_cp_app_unit STATIC ${SOURCES})
 target_include_directories(srsran_cu_cp_app_unit PRIVATE ${CMAKE_SOURCE_DIR})

apps/units/cu_cp/cu_cp_builder.cpp

@@ -11,6 +11,8 @@
 #include "cu_cp_builder.h"
 #include "cu_cp_commands.h"
 #include "cu_cp_config_translators.h"
+#include "cu_cp_unit_config.h"
+#include "cu_cp_wrapper.h"
 #include "srsran/cu_cp/cu_cp_factory.h"
 
 using namespace srsran;
@@ -20,18 +22,33 @@ cu_cp_unit srsran::build_cu_cp(const cu_cp_unit_config& cu_cp_unit_cfg, cu_cp_bu
   srsran_assert(dependencies.cu_cp_executor, "Invalid CU-CP executor");
   srsran_assert(dependencies.cu_cp_e2_exec, "Invalid E2 executor");
   srsran_assert(dependencies.cu_cp_e2_exec, "Invalid E2 executor");
+  srsran_assert(dependencies.ngap_pcap, "Invalid NGAP PCAP");
+  srsran_assert(dependencies.broker, "Invalid IO broker");
 
   srs_cu_cp::cu_cp_configuration cu_cp_cfg = generate_cu_cp_config(cu_cp_unit_cfg);
   cu_cp_cfg.services.cu_cp_executor        = dependencies.cu_cp_executor;
   cu_cp_cfg.services.cu_cp_e2_exec         = dependencies.cu_cp_e2_exec;
   cu_cp_cfg.services.timers                = dependencies.timers;
 
-  for (unsigned pos = 0; pos < dependencies.n2_clients.size(); pos++) {
-    cu_cp_cfg.ngaps[pos].n2_gw = dependencies.n2_clients[pos].get();
+  // Create N2 Client Gateways.
+  std::vector<std::unique_ptr<srs_cu_cp::n2_connection_client>> n2_clients;
+  n2_clients.push_back(
+      srs_cu_cp::create_n2_connection_client(generate_n2_client_config(cu_cp_unit_cfg.amf_config.no_core,
+                                                                       cu_cp_unit_cfg.amf_config.amf,
+                                                                       *dependencies.ngap_pcap,
+                                                                       *dependencies.broker)));
+
+  for (const auto& amf : cu_cp_unit_cfg.extra_amfs) {
+    n2_clients.push_back(srs_cu_cp::create_n2_connection_client(generate_n2_client_config(
+        cu_cp_unit_cfg.amf_config.no_core, amf, *dependencies.ngap_pcap, *dependencies.broker)));
+  }
+
+  for (unsigned pos = 0; pos < n2_clients.size(); pos++) {
+    cu_cp_cfg.ngaps[pos].n2_gw = n2_clients[pos].get();
   }
 
   cu_cp_unit cu_cmd_wrapper;
-  cu_cmd_wrapper.unit = create_cu_cp(cu_cp_cfg);
+  cu_cmd_wrapper.unit = std::make_unique<cu_cp_wrapper>(std::move(n2_clients), create_cu_cp(cu_cp_cfg));
 
   // Add the commands;
   cu_cmd_wrapper.commands.push_back(std::make_unique<handover_app_command>(cu_cmd_wrapper.unit->get_command_handler()));

apps/units/cu_cp/cu_cp_builder.h

@@ -15,6 +15,8 @@
 
 namespace srsran {
 
+class dlt_pcap;
+class io_broker;
 struct cu_cp_unit_config;
 struct worker_manager;
 
@@ -24,10 +26,11 @@ class n2_connection_client;
 
 /// CU-CP build dependencies.
 struct cu_cp_build_dependencies {
-  task_executor*                                                cu_cp_executor = nullptr;
-  task_executor*                                                cu_cp_e2_exec  = nullptr;
-  std::vector<std::unique_ptr<srs_cu_cp::n2_connection_client>> n2_clients;
-  timer_manager*                                                timers = nullptr;
+  task_executor* cu_cp_executor = nullptr;
+  task_executor* cu_cp_e2_exec  = nullptr;
+  timer_manager* timers         = nullptr;
+  dlt_pcap*      ngap_pcap      = nullptr;
+  io_broker*     broker         = nullptr;
 };
 
 /// Wraps the CU-CP and its supported application commands.

apps/units/cu_cp/cu_cp_wrapper.cpp

@@ -0,0 +1,56 @@
+/*
+ *
+ * Copyright 2021-2024 Software Radio Systems Limited
+ *
+ * By using this file, you agree to the terms and conditions set
+ * forth in the LICENSE file which can be found at the top level of
+ * the distribution.
+ *
+ */
+
+#include "cu_cp_wrapper.h"
+
+using namespace srsran;
+using namespace srs_cu_cp;
+
+cu_cp_wrapper::cu_cp_wrapper(std::vector<std::unique_ptr<srs_cu_cp::n2_connection_client>> n2_clients_,
+                             std::unique_ptr<srs_cu_cp::cu_cp>                             cu_cp_) :
+  n2_clients(std::move(n2_clients_)), cu_cp(std::move(cu_cp_))
+{
+  srsran_assert(cu_cp, "Invalid CU-CP object");
+}
+
+cu_cp_f1c_handler& cu_cp_wrapper::get_f1c_handler()
+{
+  return cu_cp->get_f1c_handler();
+}
+
+cu_cp_e1_handler& cu_cp_wrapper::get_e1_handler()
+{
+  return cu_cp->get_e1_handler();
+}
+
+cu_cp_ng_handler& cu_cp_wrapper::get_ng_handler()
+{
+  return cu_cp->get_ng_handler();
+}
+
+cu_cp_command_handler& cu_cp_wrapper::get_command_handler()
+{
+  return cu_cp->get_command_handler();
+}
+
+metrics_handler& cu_cp_wrapper::get_metrics_handler()
+{
+  return cu_cp->get_metrics_handler();
+}
+
+bool cu_cp_wrapper::start()
+{
+  return cu_cp->start();
+}
+
+void cu_cp_wrapper::stop()
+{
+  cu_cp->stop();
+}

apps/units/cu_cp/cu_cp_wrapper.h

@@ -0,0 +1,47 @@
+/*
+ *
+ * Copyright 2021-2024 Software Radio Systems Limited
+ *
+ * By using this file, you agree to the terms and conditions set
+ * forth in the LICENSE file which can be found at the top level of
+ * the distribution.
+ *
+ */
+
+#pragma once
+
+#include "srsran/cu_cp/cu_cp.h"
+#include "srsran/ngap/gateways/n2_connection_client.h"
+
+namespace srsran {
+
+/// \brief CU-CP wrapper implementation.
+///
+/// The purpose of this wrapper is to keep the life cycle of the objects related only to the CU-CP.
+class cu_cp_wrapper : public srs_cu_cp::cu_cp
+{
+public:
+  cu_cp_wrapper(std::vector<std::unique_ptr<srs_cu_cp::n2_connection_client>> n2_clients_,
+                std::unique_ptr<srs_cu_cp::cu_cp>                             cu_cp_);
+
+  // See interface for documentation.
+  srs_cu_cp::cu_cp_f1c_handler& get_f1c_handler() override;
+  // See interface for documentation.
+  srs_cu_cp::cu_cp_e1_handler& get_e1_handler() override;
+  // See interface for documentation.
+  srs_cu_cp::cu_cp_ng_handler& get_ng_handler() override;
+  // See interface for documentation.
+  srs_cu_cp::cu_cp_command_handler& get_command_handler() override;
+  // See interface for documentation.
+  srs_cu_cp::metrics_handler& get_metrics_handler() override;
+  // See interface for documentation.
+  bool start() override;
+  // See interface for documentation.
+  void stop() override;
+
+private:
+  std::vector<std::unique_ptr<srs_cu_cp::n2_connection_client>> n2_clients;
+  std::unique_ptr<srs_cu_cp::cu_cp>                             cu_cp;
+};
+
+} // namespace srsran