set default gtpu tunnel close timeout to infinity

lib/include/srsran/interfaces/enb_gtpu_interfaces.h

@@ -24,7 +24,7 @@ struct gtpu_args_t {
   std::string embms_m1u_multiaddr;
   std::string embms_m1u_if_addr;
   bool        embms_enable                 = false;
-  uint32_t    indirect_tunnel_timeout_msec = 2000;
+  uint32_t    indirect_tunnel_timeout_msec = 0;
 };
 
 // GTPU interface for PDCP

srsenb/enb.conf.example

@@ -307,7 +307,7 @@ enable = false
 # nof_prealloc_ues:     Number of UE memory resources to preallocate during eNB initialization for faster UE creation (Default 8)
 # eea_pref_list:        Ordered preference list for the selection of encryption algorithm (EEA) (default: EEA0, EEA2, EEA1).
 # eia_pref_list:        Ordered preference list for the selection of integrity algorithm (EIA) (default: EIA2, EIA1, EIA0).
-# gtpu_tunnel_timeout:  Maximum time that GTPU takes to release indirect forwarding tunnel since the last received GTPU PDU.
+# gtpu_tunnel_timeout:  Time that GTPU takes to release indirect forwarding tunnel since the last received GTPU PDU (0 for no timer).
 #
 #####################################################################
 [expert]
@@ -332,4 +332,4 @@ enable = false
 #nof_prealloc_ues     = 8
 #eea_pref_list = EEA0, EEA2, EEA1
 #eia_pref_list = EIA2, EIA1, EIA0
-#gtpu_tunnel_timeout = 2000
+#gtpu_tunnel_timeout = 0

srsenb/src/main.cc

@@ -217,7 +217,7 @@ void parse_args(all_args_t* args, int argc, char* argv[])
     ("expert.nof_prealloc_ues", bpo::value<uint32_t>(&args->stack.mac.nof_prealloc_ues)->default_value(8), "Number of UE resources to preallocate during eNB initialization")
     ("expert.max_mac_dl_kos", bpo::value<uint32_t>(&args->general.max_mac_dl_kos)->default_value(100), "Maximum number of consecutive KOs in DL before triggering the UE's release")
     ("expert.max_mac_ul_kos", bpo::value<uint32_t>(&args->general.max_mac_ul_kos)->default_value(100), "Maximum number of consecutive KOs in UL before triggering the UE's release")
-    ("expert.gtpu_tunnel_timeout", bpo::value<uint32_t>(&args->stack.gtpu_indirect_tunnel_timeout_msec)->default_value(2000), "Maximum time that GTPU takes to release indirect forwarding tunnel since the last received GTPU PDU.")
+    ("expert.gtpu_tunnel_timeout", bpo::value<uint32_t>(&args->stack.gtpu_indirect_tunnel_timeout_msec)->default_value(0), "Maximum time that GTPU takes to release indirect forwarding tunnel since the last received GTPU PDU. (0 for infinity)")
 
 
     // eMBMS section

srsenb/src/stack/upper/gtpu.cc

@@ -244,6 +244,7 @@ void gtpu_tunnel_manager::set_tunnel_priority(uint32_t before_teid, uint32_t aft
   // TS 36.300 - On detection of the "end marker", the target eNB may also initiate the release of the data forwarding
   //             resource. However, the release of the data forwarding resource is implementation dependent and could
   //             also be based on other mechanisms (e.g. timer-based mechanism).
+  if (gtpu_args->indirect_tunnel_timeout_msec > 0) {
     before_tun.rx_timer = task_sched.get_unique_timer();
     before_tun.rx_timer.set(gtpu_args->indirect_tunnel_timeout_msec, [this, before_teid](uint32_t tid) {
       // Note: This will self-destruct the callback object
@@ -253,6 +254,7 @@ void gtpu_tunnel_manager::set_tunnel_priority(uint32_t before_teid, uint32_t aft
       remove_tunnel(before_teid);
     });
     before_tun.rx_timer.run();
+  }
 }
 
 void gtpu_tunnel_manager::handle_rx_pdcp_sdu(uint32_t teid)

srsenb/test/upper/gtpu_test.cc

@@ -209,6 +209,8 @@ enum class tunnel_test_event { success, wait_end_marker_timeout };
 
 int test_gtpu_direct_tunneling(tunnel_test_event event)
 {
+  std::random_device    rd;
+  std::mt19937          g(rd());
   srslog::basic_logger& logger = srslog::fetch_basic_logger("TEST");
   logger.info("\n\n**** Test GTPU Direct Tunneling ****\n");
   uint16_t           rnti = 0x46, rnti2 = 0x50;
@@ -237,6 +239,7 @@ int test_gtpu_direct_tunneling(tunnel_test_event event)
   gtpu_args_t  gtpu_args;
   gtpu_args.gtp_bind_addr                = senb_addr_str;
   gtpu_args.mme_addr                     = sgw_addr_str;
+  gtpu_args.indirect_tunnel_timeout_msec = std::uniform_int_distribution<uint32_t>{500, 2000}(g);
   senb_gtpu.init(gtpu_args, &senb_pdcp);
   gtpu_args.gtp_bind_addr = tenb_addr_str;
   tenb_gtpu.init(gtpu_args, &tenb_pdcp);
@@ -262,8 +265,6 @@ int test_gtpu_direct_tunneling(tunnel_test_event event)
   props.forward_from_teidin         = senb_teid_in;
   senb_gtpu.add_bearer(rnti, drb1, tenb_addr, dl_tenb_teid_in, &props);
 
-  std::random_device   rd;
-  std::mt19937         g(rd());
   std::vector<uint8_t> data_vec(10);
   std::iota(data_vec.begin(), data_vec.end(), 0);
   std::vector<uint8_t>  encoded_data;