SRSUE: Refactored/Fixed RRC connection Re-establishment and minor CLang Format/Tidy fixes

srsue/hdr/stack/rrc/rrc.h

@@ -118,20 +118,18 @@ class cell_t
   }
 
   cell_t() {
-    phy_interface_rrc_lte::phy_cell_t tmp;
+    phy_interface_rrc_lte::phy_cell_t tmp = {};
-    ZERO_OBJECT(tmp);
-    ZERO_OBJECT(phy_cell);
     cell_t(tmp, 0);
   }
-  cell_t(phy_interface_rrc_lte::phy_cell_t phy_cell, float rsrp)
+  cell_t(phy_interface_rrc_lte::phy_cell_t phy_cell, float rsrp_)
   {
-    gettimeofday(&last_update, NULL);
+    gettimeofday(&last_update, nullptr);
     this->has_valid_sib1 = false;
     this->has_valid_sib2 = false;
     this->has_valid_sib3 = false;
     this->has_valid_sib13 = false;
     this->phy_cell        = phy_cell;
-    this->rsrp = rsrp;
+    rsrp                  = rsrp_;
     in_sync = true;
     bzero(&sib1, sizeof(sib1));
     bzero(&sib2, sizeof(sib2));
@@ -147,12 +145,13 @@ class cell_t
     return phy_cell.cell.id;
   }
 
-  void set_rsrp(float rsrp) {
+  void set_rsrp(float rsrp_)
-    if (!std::isnan(rsrp)) {
+  {
-      this->rsrp = rsrp;
+    if (!std::isnan(rsrp_)) {
+      rsrp = rsrp_;
     }
     in_sync = true;
-    gettimeofday(&last_update, NULL);
+    gettimeofday(&last_update, nullptr);
   }
 
   float get_rsrp() {
@@ -262,9 +261,9 @@ class cell_t
     return std::string{buf};
   }
 
-  phy_interface_rrc_lte::phy_cell_t phy_cell;
+  phy_interface_rrc_lte::phy_cell_t phy_cell = {};
-  bool                              in_sync;
+  bool                              in_sync  = false;
-  bool                              has_mcch;
+  bool                              has_mcch = false;
   asn1::rrc::sib_type1_s            sib1;
   asn1::rrc::sib_type2_s            sib2;
   asn1::rrc::sib_type3_s            sib3;
@@ -272,14 +271,14 @@ class cell_t
   asn1::rrc::mcch_msg_s             mcch;
 
 private:
-  float    rsrp;
+  float rsrp = NAN;
 
-  struct timeval last_update;
+  struct timeval last_update = {};
 
-  bool     has_valid_sib1;
+  bool has_valid_sib1  = false;
-  bool     has_valid_sib2;
+  bool has_valid_sib2  = false;
-  bool     has_valid_sib3;
+  bool has_valid_sib3  = false;
-  bool     has_valid_sib13;
+  bool has_valid_sib13 = false;
 };
 
 class rrc : public rrc_interface_nas,
@@ -417,8 +416,8 @@ private:
 
   // RRC constants and timers
   srslte::timer_handler*              timers = nullptr;
-  uint32_t                            n310_cnt, N310 = 0;
+  uint32_t                            n310_cnt = 0, N310 = 0;
-  uint32_t                            n311_cnt, N311 = 0;
+  uint32_t                            n311_cnt = 0, N311 = 0;
   srslte::timer_handler::unique_timer t300, t301, t302, t310, t311, t304;
 
   // Radio bearers
@@ -471,10 +470,6 @@ private:
   std::string                    print_neighbour_cells();
 
   bool initiated                  = false;
-  asn1::rrc::reest_cause_e m_reest_cause                                  = asn1::rrc::reest_cause_e::nulltype;
-  uint16_t                 m_reest_rnti               = 0;
-  uint16_t                 m_reest_source_pci                             = 0;
-  bool                     reestablishment_started                        = false;
   bool reestablishment_successful = false;
 
   // Measurements sub-class
@@ -621,6 +616,7 @@ private:
   class process_pcch_proc;
   class go_idle_proc;
   class cell_reselection_proc;
+  class connection_reest_proc;
   srslte::proc_t<cell_search_proc, phy_interface_rrc_lte::cell_search_ret_t> cell_searcher;
   srslte::proc_t<si_acquire_proc>                                            si_acquirer;
   srslte::proc_t<serving_cell_config_proc>                                   serv_cell_cfg;
@@ -630,6 +626,7 @@ private:
   srslte::proc_t<connection_request_proc>                                    conn_req_proc;
   srslte::proc_t<plmn_search_proc>                                           plmn_searcher;
   srslte::proc_t<cell_reselection_proc>                                      cell_reselector;
+  srslte::proc_t<connection_reest_proc>                                      connection_reest;
 
   srslte::proc_manager_list_t callback_list;
 
@@ -647,7 +644,7 @@ private:
 
   // Senders
   void send_con_request(srslte::establishment_cause_t cause);
-  void send_con_restablish_request();
+  void send_con_restablish_request(asn1::rrc::reest_cause_e cause, uint16_t rnti, uint16_t pci);
   void send_con_restablish_complete();
   void send_con_setup_complete(srslte::unique_byte_buffer_t nas_msg);
   void send_ul_info_transfer(srslte::unique_byte_buffer_t nas_msg);
@@ -674,8 +671,7 @@ private:
   void radio_link_failure();
   void leave_connected();
   void stop_timers();
-  void init_con_restablish_request(asn1::rrc::reest_cause_e cause);
+  void start_con_restablishment(asn1::rrc::reest_cause_e cause);
-  void proc_con_restablish_request();
   void start_cell_reselection();
 
   void log_rr_config_common();

srsue/hdr/stack/rrc/rrc_procedures.h

@@ -230,6 +230,28 @@ private:
   srslte::proc_future_t<cs_result_t> cell_selection_fut;
 };
 
+class rrc::connection_reest_proc
+{
+public:
+  explicit connection_reest_proc(rrc* rrc_);
+  srslte::proc_outcome_t init(asn1::rrc::reest_cause_e cause);
+  srslte::proc_outcome_t step();
+  static const char*     name() { return "Connection re-establishment"; }
+
+private:
+  enum class state_t { init, cell_reselection, cell_configuration, cell_criteria, success, error } state;
+
+  rrc*                     rrc_ptr          = nullptr;
+  asn1::rrc::reest_cause_e reest_cause      = asn1::rrc::reest_cause_e::nulltype;
+  uint16_t                 reest_rnti       = 0;
+  uint16_t                 reest_source_pci = 0;
+
+  void step_init();
+  void step_cell_reselection();
+  void step_cell_configuration();
+  void step_cell_criteria();
+};
+
 } // namespace srsue
 
 #endif // SRSLTE_RRC_PROCEDURES_H

srsue/src/stack/rrc/rrc.cc

@@ -62,13 +62,13 @@ rrc::rrc(srslte::log* rrc_log_) :
   conn_req_proc(this),
   plmn_searcher(this),
   cell_reselector(this),
+  connection_reest(this),
   serving_cell(unique_cell_t(new cell_t({}, 0.0)))
 {
+  // Do nothing
 }
 
-rrc::~rrc()
+rrc::~rrc() = default;
-{
-}
 
 static void srslte_rrc_handler(asn1::srsasn_logger_level_t level, void* ctx, const char* str)
 {
@@ -233,10 +233,6 @@ void rrc::run_tti(uint32_t tti)
       }
       break;
     case RRC_STATE_CONNECTED:
-      // Performing reestablishment cell selection
-      if (m_reest_cause != asn1::rrc::reest_cause_e::nulltype) {
-        proc_con_restablish_request();
-      }
       measurements.run_tti(tti);
       break;
     default:
@@ -792,7 +788,7 @@ void rrc::radio_link_failure() {
   rrc_log->warning("Detected Radio-Link Failure\n");
   rrc_log->console("Warning: Detected Radio-Link Failure\n");
   if (state == RRC_STATE_CONNECTED) {
-    init_con_restablish_request(asn1::rrc::reest_cause_e::other_fail);
+    start_con_restablishment(asn1::rrc::reest_cause_e::other_fail);
   }
 }
 
@@ -882,15 +878,11 @@ void rrc::send_con_request(srslte::establishment_cause_t cause)
 }
 
 /* RRC connection re-establishment procedure (5.3.7.4) */
-void rrc::send_con_restablish_request()
+void rrc::send_con_restablish_request(asn1::rrc::reest_cause_e cause, uint16_t crnti, uint16_t pci)
 {
-  uint16_t crnti;
-  uint16_t pci;
   uint32_t cellid;
 
   // Clean reestablishment type
-  asn1::rrc::reest_cause_e cause = m_reest_cause;
-  m_reest_cause                  = asn1::rrc::reest_cause_e::nulltype;
   reestablishment_successful     = false;
 
   if (cause == asn1::rrc::reest_cause_e::ho_fail) {
@@ -899,11 +891,8 @@ void rrc::send_con_restablish_request()
     cellid = ho_src_cell.get_cell_id();
   } else if (cause == asn1::rrc::reest_cause_e::other_fail) {
     // use source PCI after RLF
-    crnti  = m_reest_rnti;
-    pci    = m_reest_source_pci;
     cellid = serving_cell->get_cell_id();
   } else {
-    crnti  = m_reest_rnti;
     pci    = serving_cell->get_pci();
     cellid = serving_cell->get_cell_id();
   }
@@ -1264,7 +1253,7 @@ bool rrc::con_reconfig(asn1::rrc::rrc_conn_recfg_s* reconfig)
 // HO failure from T304 expiry 5.3.5.6
 void rrc::ho_failed()
 {
-  init_con_restablish_request(asn1::rrc::reest_cause_e::ho_fail);
+  start_con_restablishment(asn1::rrc::reest_cause_e::ho_fail);
 }
 
 // Reconfiguration failure or Section 5.3.5.5
@@ -1280,7 +1269,7 @@ void rrc::con_reconfig_failed()
 
   if (security_is_activated) {
     // Start the Reestablishment Procedure
-    init_con_restablish_request(asn1::rrc::reest_cause_e::recfg_fail);
+    start_con_restablishment(asn1::rrc::reest_cause_e::recfg_fail);
   } else {
     start_go_idle();
   }
@@ -1315,7 +1304,6 @@ void rrc::leave_connected()
 {
   rrc_log->console("RRC IDLE\n");
   rrc_log->info("Leaving RRC_CONNECTED state\n");
-  m_reest_cause         = asn1::rrc::reest_cause_e::nulltype;
   state = RRC_STATE_IDLE;
   drb_up = false;
   security_is_activated = false;
@@ -1357,108 +1345,13 @@ void rrc::stop_timers()
  *
  *   The parameter cause shall indicate the cause of the reestablishment according to the sections mentioned adobe.
  */
-void rrc::init_con_restablish_request(asn1::rrc::reest_cause_e cause)
+void rrc::start_con_restablishment(asn1::rrc::reest_cause_e cause)
 {
-  // Save Current RNTI before MAC Reset
+  if (not connection_reest.launch(cause)) {
-  mac_interface_rrc::ue_rnti_t uernti;
+    rrc_log->info("Failed to launch connection re-establishment pocedure\n");
-  mac->get_rntis(&uernti);
-
-  // If security is activated, RRC connected and C-RNTI available
-  if (security_is_activated && state == RRC_STATE_CONNECTED && uernti.crnti != 0) {
-    // Save reestablishment cause and current C-RNTI
-    m_reest_rnti  = uernti.crnti;
-    m_reest_cause = cause;
-    m_reest_source_pci = serving_cell->get_pci(); // needed for reestablishment with another cell
-
-    reestablishment_started = false;
-
-    // initiation of reestablishment procedure as indicates in 3GPP 36.331 Section 5.3.7.2
-    rrc_log->info("Initiating RRC Connection Reestablishment Procedure\n");
-  } else {
-    // 3GPP 36.331 Section 5.3.7.1
-    // If AS security has not been activated, the UE does not initiate the procedure but instead
-    // moves to RRC_IDLE directly
-    start_go_idle();
-  }
-}
-
-/* Implementation of procedure in 3GPP 36.331 Section 5.3.7.3: Actions following cell selection while T311 is running
- */
-void rrc::proc_con_restablish_request()
-{
-  if (!reestablishment_started) {
-
-    reestablishment_started = true;
-
-    rrc_log->info("Resetting timers and MAC in RRC Connection Reestablishment Procedure\n");
-
-    // stop timer T310, if running;
-    t310.stop();
-
-    // start timer T311;
-    t311.run();
-
-    // Suspend all RB except SRB0
-    for (int i = 1; i < SRSLTE_N_RADIO_BEARERS; i++) {
-      if (rlc->has_bearer(i)) {
-        rlc->suspend_bearer(i);
-      }
   }
 
-    // reset MAC;
+  callback_list.add_proc(connection_reest);
-    mac->reset();
-
-    // apply the default physical channel configuration as specified in 9.2.4;
-    set_phy_default_pucch_srs();
-
-    // apply the default semi-persistent scheduling configuration as specified in 9.2.3;
-    // N.A.
-
-    // apply the default MAC main configuration as specified in 9.2.2;
-    apply_mac_config_dedicated_default();
-
-    // perform cell selection in accordance with the cell selection process as specified in TS 36.304 [4];
-    start_cell_reselection();
-  }
-
-  // Check timer...
-  if (t311.is_running()) {
-    // Wait until we're synced and have obtained SIBs
-    if (serving_cell->in_sync && serving_cell->has_sib1() && serving_cell->has_sib2() && serving_cell->has_sib3()) {
-      // Perform cell selection in accordance to 36.304
-      if (cell_selection_criteria(serving_cell->get_rsrp())) {
-        // Actions following cell reselection while T311 is running 5.3.7.3
-        // Upon selecting a suitable E-UTRA cell, the UE shall:
-        rrc_log->info("Cell Selection criteria passed after %dms. Sending RRC Connection Reestablishment Request\n",
-                      t311.value());
-
-        // stop timer T311;
-        t311.stop();
-
-        // start timer T301;
-        t301.run();
-
-        // apply the timeAlignmentTimerCommon included in SystemInformationBlockType2;
-        // TODO
-
-        // initiate transmission of the RRCConnectionReestablishmentRequest message in accordance with 5.3.7.4;
-        send_con_restablish_request();
-      } else {
-        // Upon selecting an inter-RAT cell
-        rrc_log->warning("Reestablishment Cell Selection criteria failed.\n");
-        rrc_log->console("Reestablishment Cell Selection criteria failed (rsrp=%.2f)\n",
-                         serving_cell->get_rsrp());
-        leave_connected();
-      }
-    } else {
-      // No synchronized, do nothing
-    }
-  } else {
-    // t311 expired or stopped
-    rrc_log->info("T311 expired while selecting cell. Going to IDLE\n");
-    rrc_log->console("T311 expired while selecting cell. Going to IDLE\n");
-    leave_connected();
-  }
 }
 
 void rrc::start_cell_reselection()

srsue/src/stack/rrc/rrc_procedures.cc

@@ -869,4 +869,211 @@ proc_outcome_t rrc::cell_reselection_proc::step()
   return srslte::proc_outcome_t::success;
 }
 
+/**************************************
+ *    RRC Connection Re-establishment procedure
+ *************************************/
+
+rrc::connection_reest_proc::connection_reest_proc(srsue::rrc* rrc_) : rrc_ptr(rrc_), state(state_t::init) {}
+
+proc_outcome_t rrc::connection_reest_proc::init(asn1::rrc::reest_cause_e cause)
+{
+  Info("Starting...\n");
+
+  // Save Current RNTI before MAC Reset
+  mac_interface_rrc::ue_rnti_t uernti;
+  rrc_ptr->mac->get_rntis(&uernti);
+
+  // If security is activated, RRC connected and C-RNTI available
+  if (rrc_ptr->security_is_activated && rrc_ptr->state == RRC_STATE_CONNECTED && uernti.crnti != 0) {
+    // Save reestablishment cause and current C-RNTI
+    reest_rnti       = uernti.crnti;
+    reest_cause      = cause;
+    reest_source_pci = rrc_ptr->serving_cell->get_pci(); // needed for reestablishment with another cell
+
+    // the initiation of reestablishment procedure as indicates in 3GPP 36.331 Section 5.3.7.2
+    // Cannot be called from here because it has PHY-MAC re-configuration that should be performed in a different thread
+    Info("Conditions are meet\n");
+    state = state_t::init;
+
+  } else {
+    // 3GPP 36.331 Section 5.3.7.1
+    // If AS security has not been activated, the UE does not initiate the procedure but instead
+    // moves to RRC_IDLE directly
+    Info("Conditions are NOT meet\n");
+    rrc_ptr->start_go_idle();
+    state = state_t::success;
+  }
+
+  return proc_outcome_t::yield;
+}
+
+void rrc::connection_reest_proc::step_init()
+{
+  // initiation of reestablishment procedure as indicates in 3GPP 36.331 Section 5.3.7.2
+  Info("Initiating RRC Connection Reestablishment Procedure\n");
+
+  // stop timer T310, if running;
+  rrc_ptr->t310.stop();
+
+  // start timer T311;
+  rrc_ptr->t311.run();
+
+  // Suspend all RB except SRB0
+  for (int i = 1; i < SRSLTE_N_RADIO_BEARERS; i++) {
+    if (rrc_ptr->rlc->has_bearer(i)) {
+      rrc_ptr->rlc->suspend_bearer(i);
+    }
+  }
+
+  // reset MAC;
+  rrc_ptr->mac->reset();
+
+  // apply the default physical channel configuration as specified in 9.2.4;
+  rrc_ptr->set_phy_default_pucch_srs();
+
+  // apply the default semi-persistent scheduling configuration as specified in 9.2.3;
+  // N.A.
+
+  // apply the default MAC main configuration as specified in 9.2.2;
+  rrc_ptr->apply_mac_config_dedicated_default();
+
+  // Launch cell reselection
+  if (rrc_ptr->cell_reselector.launch()) {
+    state = state_t::cell_reselection;
+  } else {
+    Error("Failed to initiate a Cell re-selection procedure...\n");
+    state = state_t::error;
+  }
+}
+
+void rrc::connection_reest_proc::step_cell_reselection()
+{
+  if (!rrc_ptr->t311.is_running()) {
+    Info("During cell reselection, T311 expired. Aborting.\n");
+    state = state_t::success;
+  } else if (rrc_ptr->cell_reselector.run()) {
+    // Keep running, do nothing
+  } else if (!rrc_ptr->serving_cell->in_sync) {
+    Info("Serving cell is out-of-sync, re-launching re-selection procedure\n");
+    if (rrc_ptr->cell_reselector.launch()) {
+      state = state_t::cell_reselection;
+    } else {
+      // Error launching procedure
+      state = state_t::error;
+    }
+  } else if (rrc_ptr->serving_cell->has_sib1() && rrc_ptr->serving_cell->has_sib2() &&
+             rrc_ptr->serving_cell->has_sib3()) {
+    Info("In-sync, SIBs available. Going to cell criteria\n");
+    state = state_t::cell_criteria;
+  } else {
+    Info("SIBs missing (%d, %d, %d), launching serving cell configuration procedure\n",
+         rrc_ptr->serving_cell->has_sib1(),
+         rrc_ptr->serving_cell->has_sib2(),
+         rrc_ptr->serving_cell->has_sib3());
+    std::vector<uint32_t> required_sibs = {1, 2, 3};
+    if (rrc_ptr->serv_cell_cfg.launch(required_sibs)) {
+      state = state_t::cell_configuration;
+    } else {
+      Error("Failed to initiate configure serving cell\n");
+      state = state_t::error;
+    }
+  }
+}
+
+void rrc::connection_reest_proc::step_cell_configuration()
+{
+  if (!rrc_ptr->t311.is_running()) {
+    Info("During cell configuration, T311 expired. Aborting.\n");
+    state = state_t::success;
+  } else if (rrc_ptr->serv_cell_cfg.run()) {
+    // Keep running, do nothing
+  } else if (!rrc_ptr->serving_cell->in_sync) {
+    Info("Serving cell is out-of-sync, re-launching re-selection procedure\n");
+    if (rrc_ptr->cell_reselector.launch()) {
+      state = state_t::cell_reselection;
+    } else {
+      Error("Failed to initiate a Cell re-selection procedure...\n");
+      state = state_t::error;
+    }
+  } else if (rrc_ptr->serving_cell->has_sib1() && rrc_ptr->serving_cell->has_sib2() &&
+             rrc_ptr->serving_cell->has_sib3()) {
+    Info("SIBs available. Going to cell criteria\n");
+    state = state_t::cell_criteria;
+  } else {
+    Error("Failed to configure serving cell\n");
+    state = state_t::error;
+  }
+}
+
+void rrc::connection_reest_proc::step_cell_criteria()
+{
+  // Wait until we're synced and have obtained SIBs
+  // Perform cell selection in accordance to 36.304
+  if (!rrc_ptr->t311.is_running()) {
+    Info("During cell selection criteria, T311 expired. Aborting.\n");
+    state = state_t::success;
+  } else if (rrc_ptr->cell_selection_criteria(rrc_ptr->serving_cell->get_rsrp())) {
+    // Actions following cell reselection while T311 is running 5.3.7.3
+    // Upon selecting a suitable E-UTRA cell, the UE shall:
+    Info("Cell Selection criteria passed after %dms. Sending RRC Connection Reestablishment Request\n",
+         rrc_ptr->t311.value());
+
+    // stop timer T311;
+    rrc_ptr->t311.stop();
+
+    // start timer T301;
+    rrc_ptr->t301.run();
+
+    // apply the timeAlignmentTimerCommon included in SystemInformationBlockType2;
+    // TODO
+
+    // initiate transmission of the RRCConnectionReestablishmentRequest message in accordance with 5.3.7.4;
+    rrc_ptr->send_con_restablish_request(reest_cause, reest_rnti, reest_source_pci);
+  } else {
+    // Upon selecting an inter-RAT cell
+    Warning("Reestablishment Cell Selection criteria failed.\n");
+    rrc_ptr->leave_connected();
+  }
+  state = state_t::success;
+}
+
+proc_outcome_t rrc::connection_reest_proc::step()
+{
+  proc_outcome_t proc_outcome = srslte::proc_outcome_t::yield;
+
+  /*
+   * Implementation of procedure in 3GPP 36.331 Section 5.3.7.3: Actions following cell selection while T311 is running
+   */
+  switch (state) {
+
+    case state_t::init:
+      step_init();
+      break;
+
+    case state_t::cell_reselection:
+      step_cell_reselection();
+      break;
+
+    case state_t::cell_configuration:
+      step_cell_configuration();
+      break;
+
+    case state_t::cell_criteria:
+      step_cell_criteria();
+      break;
+
+    case state_t::success:
+      Info("Finished successfully\n");
+      proc_outcome = srslte::proc_outcome_t::success;
+      break;
+
+    case state_t::error:
+      Info("Finished with error\n");
+      proc_outcome = srslte::proc_outcome_t::error;
+      break;
+  }
+
+  return proc_outcome;
+}
+
 } // namespace srsue