fix drb reestablishment during handover

lib/include/srslte/rrc/rrc_cfg_utils.h

@@ -105,6 +105,17 @@ typename Container::iterator add_rrc_obj(Container& c, const typename Container:
   return it;
 }
 
+template <typename Container, typename IdType>
+bool rem_rrc_obj_id(Container& c, IdType id)
+{
+  auto it = sorted_find_rrc_obj_id(c, id);
+  if (it != c.end()) {
+    c.erase(it);
+    return true;
+  }
+  return false;
+}
+
 /**
  * Find rrc obj id gap in list of rrc objs (e.g. {1, 2, 4} -> 3)
  * Expects list to be sorted
@@ -234,6 +245,21 @@ void compute_cfg_diff(const toAddModList& src_list,
                       toAddModList&       add_diff_list,
                       RemoveList&         rem_diff_list)
 {
+  if (&src_list == &target_list) {
+    // early exit
+    return;
+  } else if (&src_list == &add_diff_list) {
+    // use const src_list
+    toAddModList src_list2 = src_list;
+    compute_cfg_diff(src_list2, target_list, add_diff_list, rem_diff_list);
+    return;
+  } else if (&target_list == &add_diff_list) {
+    // use const target_list
+    toAddModList target_list2 = target_list;
+    compute_cfg_diff(src_list, target_list2, add_diff_list, rem_diff_list);
+    return;
+  }
+
   using it_t    = typename toAddModList::const_iterator;
   auto rem_func = [&rem_diff_list](it_t rem_it) { rem_diff_list.push_back(asn1::rrc::get_rrc_obj_id(*rem_it)); };
   auto add_func = [&add_diff_list](it_t add_it) { add_diff_list.push_back(*add_it); };

srsenb/hdr/stack/rrc/rrc_bearer_cfg.h

@@ -77,10 +77,6 @@ public:
                 const asn1::unbounded_octstring<true>*             nas_pdu);
   void release_erab(uint8_t erab_id);
   void release_erabs();
-  void reest_bearers();
-
-  bool fill_rr_cfg_ded(asn1::rrc::rr_cfg_ded_s& msg);
-  void rr_ded_cfg_complete();
 
   // Methods to apply bearer updates
   void add_gtpu_bearer(gtpu_interface_rrc* gtpu, uint32_t erab_id);
@@ -88,8 +84,6 @@ public:
 
   const std::map<uint8_t, erab_t>&        get_erabs() const { return erabs; }
   const asn1::rrc::drb_to_add_mod_list_l& get_established_drbs() const { return current_drbs; }
-  const asn1::rrc::drb_to_add_mod_list_l& get_pending_addmod_drbs() const { return drbs_to_add; }
-  srslte::span<const uint8_t>             get_pending_rem_drbs() const { return drbs_to_release; }
 
   std::map<uint8_t, std::vector<uint8_t> > erab_info_list;
   std::map<uint8_t, erab_t>                erabs;
@@ -101,10 +95,6 @@ private:
 
   // last cfg
   asn1::rrc::drb_to_add_mod_list_l current_drbs;
-
-  // pending cfg updates
-  asn1::rrc::drb_to_add_mod_list_l drbs_to_add;
-  asn1::rrc::drb_to_release_list_l drbs_to_release;
 };
 
 } // namespace srsenb

srsenb/src/stack/rrc/mac_controller.cc

@@ -56,6 +56,8 @@ sched_interface::ue_bearer_cfg_t get_bearer_default_srb2_config()
   return bearer;
 }
 
+void ue_cfg_apply_srb_updates(ue_cfg_t& ue_cfg, const srb_to_add_mod_list_l& srbs);
+
 /**
  * Adds to sched_interface::ue_cfg_t the changes present in the asn1 RRCReconfiguration message that should
  * only take effect after the RRCReconfigurationComplete is received
@@ -266,6 +268,9 @@ void rrc::ue::mac_controller::handle_intraenb_ho_cmd(const asn1::rrc::rrc_conn_r
 void rrc::ue::mac_controller::handle_ho_prep(const asn1::rrc::ho_prep_info_r8_ies_s& ho_prep)
 {
   // TODO: Apply configuration in ho_prep as a base
+  if (ho_prep.as_cfg.source_rr_cfg.srb_to_add_mod_list_present) {
+    ue_cfg_apply_srb_updates(current_sched_ue_cfg, ho_prep.as_cfg.source_rr_cfg.srb_to_add_mod_list);
+  }
 }
 
 void rrc::ue::mac_controller::set_scell_activation(const std::bitset<SRSLTE_MAX_CARRIERS>& scell_mask)
@@ -328,6 +333,37 @@ void ue_cfg_apply_phy_cfg_ded(ue_cfg_t& ue_cfg, const asn1::rrc::phys_cfg_ded_s&
   }
 }
 
+void ue_cfg_apply_srb_updates(ue_cfg_t& ue_cfg, const srb_to_add_mod_list_l& srbs)
+{
+  for (const srb_to_add_mod_s& srb : srbs) {
+    auto& bcfg = ue_cfg.ue_bearers[srb.srb_id];
+    switch (srb.srb_id) {
+      case 1:
+        bcfg = get_bearer_default_srb1_config();
+        break;
+      case 2:
+        bcfg = get_bearer_default_srb2_config();
+        break;
+      default:
+        srslte::logmap::get("RRC")->warning("Invalid SRB ID %d\n", (int)srb.srb_id);
+        bcfg = {};
+    }
+    bcfg.direction = srsenb::sched_interface::ue_bearer_cfg_t::BOTH;
+    if (srb.lc_ch_cfg_present and
+        srb.lc_ch_cfg.type().value == srb_to_add_mod_s::lc_ch_cfg_c_::types_opts::explicit_value and
+        srb.lc_ch_cfg.explicit_value().ul_specific_params_present) {
+      // NOTE: Use UL values for DL prioritization as well
+      auto& ul_params = srb.lc_ch_cfg.explicit_value().ul_specific_params;
+      bcfg.pbr        = ul_params.prioritised_bit_rate.to_number();
+      bcfg.priority   = ul_params.prio;
+      bcfg.bsd        = ul_params.bucket_size_dur.to_number();
+      if (ul_params.lc_ch_group_present) {
+        bcfg.group = ul_params.lc_ch_group;
+      }
+    }
+  }
+}
+
 void ue_cfg_apply_reconf_complete_updates(ue_cfg_t&                       ue_cfg,
                                           const rrc_conn_recfg_r8_ies_s&  conn_recfg,
                                           const cell_ctxt_dedicated_list& ue_cell_list)
@@ -353,33 +389,7 @@ void ue_cfg_apply_reconf_complete_updates(ue_cfg_t&                       ue_cfg
 
     // Apply SRB updates
     if (conn_recfg.rr_cfg_ded.srb_to_add_mod_list_present) {
-      for (const srb_to_add_mod_s& srb : conn_recfg.rr_cfg_ded.srb_to_add_mod_list) {
-        auto& bcfg = ue_cfg.ue_bearers[srb.srb_id];
-        switch (srb.srb_id) {
-          case 1:
-            bcfg = get_bearer_default_srb1_config();
-            break;
-          case 2:
-            bcfg = get_bearer_default_srb2_config();
-            break;
-          default:
-            srslte::logmap::get("RRC")->warning("Invalid SRB ID %d\n", (int)srb.srb_id);
-            bcfg = {};
-        }
-        bcfg.direction = srsenb::sched_interface::ue_bearer_cfg_t::BOTH;
-        if (srb.lc_ch_cfg_present and
-            srb.lc_ch_cfg.type().value == srb_to_add_mod_s::lc_ch_cfg_c_::types_opts::explicit_value and
-            srb.lc_ch_cfg.explicit_value().ul_specific_params_present) {
-          // NOTE: Use UL values for DL prioritization as well
-          auto& ul_params = srb.lc_ch_cfg.explicit_value().ul_specific_params;
-          bcfg.pbr        = ul_params.prioritised_bit_rate.to_number();
-          bcfg.priority   = ul_params.prio;
-          bcfg.bsd        = ul_params.bucket_size_dur.to_number();
-          if (ul_params.lc_ch_group_present) {
-            bcfg.group = ul_params.lc_ch_group;
-          }
-        }
-      }
+      ue_cfg_apply_srb_updates(ue_cfg, conn_recfg.rr_cfg_ded.srb_to_add_mod_list);
     }
   }
 

srsenb/src/stack/rrc/rrc_bearer_cfg.cc

@@ -250,7 +250,7 @@ int bearer_cfg_handler::add_erab(uint8_t
   }
 
   // Set DRBtoAddMod
-  auto drb_it                                              = srslte::add_rrc_obj_id(drbs_to_add, drbid);
+  auto drb_it                                              = srslte::add_rrc_obj_id(current_drbs, drbid);
   drb_it->lc_ch_id_present                                 = true;
   drb_it->lc_ch_id                                         = (uint8_t)lcid;
   drb_it->eps_bearer_id_present                            = true;
@@ -276,7 +276,8 @@ void bearer_cfg_handler::release_erab(uint8_t erab_id)
   }
 
   uint8_t drb_id = erab_id - 4;
-  drbs_to_release.push_back(drb_id);
+
+  srslte::rem_rrc_obj_id(current_drbs, drb_id);
 
   erabs.erase(it);
   erab_info_list.erase(erab_id);
@@ -291,32 +292,6 @@ void bearer_cfg_handler::release_erabs()
   }
 }
 
-void bearer_cfg_handler::reest_bearers()
-{
-  // Re-add all SRBs/DRBs
-  drbs_to_add = current_drbs;
-}
-
-void bearer_cfg_handler::rr_ded_cfg_complete()
-{
-  // Apply changes in internal bearer_handler DRB/SRBtoAddModLists
-  srslte::apply_addmodremlist_diff(current_drbs, drbs_to_add, drbs_to_release, current_drbs);
-
-  // Reset DRBs/SRBs to Add/mod/release
-  drbs_to_add = {};
-  drbs_to_release.resize(0);
-}
-
-bool bearer_cfg_handler::fill_rr_cfg_ded(asn1::rrc::rr_cfg_ded_s& msg)
-{
-  // Add altered bearers to message
-  msg.drb_to_add_mod_list_present = drbs_to_add.size() > 0;
-  msg.drb_to_add_mod_list         = drbs_to_add;
-  msg.drb_to_release_list_present = drbs_to_release.size() > 0;
-  msg.drb_to_release_list         = drbs_to_release;
-  return msg.srb_to_add_mod_list_present or msg.drb_to_add_mod_list_present or msg.drb_to_release_list_present;
-}
-
 void bearer_cfg_handler::add_gtpu_bearer(srsenb::gtpu_interface_rrc* gtpu, uint32_t erab_id)
 {
   auto it = erabs.find(erab_id);

srsenb/src/stack/rrc/rrc_mobility.cc

@@ -1153,17 +1153,17 @@ void rrc::ue::rrc_mobility::handle_ho_req(idle_st& s, const ho_req_rx_ev& ho_req
   }
   ho_cmd_pdu->N_bytes = bref2.distance_bytes();
 
+  apply_rr_cfg_ded_diff(rrc_ue->current_rr_cfg, recfg_r8.rr_cfg_ded);
+
   /* Configure remaining layers based on pending changes */
   // Update RLC + PDCP SRBs (no DRBs until MME Status Transfer)
-  rrc_ue->apply_pdcp_srb_updates(recfg_r8.rr_cfg_ded);
-  rrc_ue->apply_rlc_rb_updates(recfg_r8.rr_cfg_ded);
+  rrc_ue->apply_pdcp_srb_updates(rrc_ue->current_rr_cfg);
+  rrc_ue->apply_rlc_rb_updates(rrc_ue->current_rr_cfg);
   // Update MAC
   rrc_ue->mac_ctrl->handle_target_enb_ho_cmd(recfg_r8);
   // Apply PHY updates
   rrc_ue->apply_reconf_phy_config(recfg_r8, true);
 
-  apply_rr_cfg_ded_diff(rrc_ue->current_rr_cfg, recfg_r8.rr_cfg_ded);
-
   /* send S1AP HandoverRequestAcknowledge */
   std::vector<asn1::fixed_octstring<4, true> > admitted_erabs;
   for (auto& erab : rrc_ue->bearer_list.get_erabs()) {
@@ -1232,6 +1232,9 @@ bool rrc::ue::rrc_mobility::apply_ho_prep_cfg(const ho_prep_info_r8_ies_s&    ho
     }
   }
 
+  // Save source eNB UE RR cfg as a starting point
+  apply_rr_cfg_ded_diff(rrc_ue->current_rr_cfg, ho_prep.as_cfg.source_rr_cfg);
+
   // Save source UE MAC configuration as a base
   rrc_ue->mac_ctrl->handle_ho_prep(ho_prep);
 
@@ -1266,7 +1269,7 @@ void rrc::ue::rrc_mobility::handle_status_transfer(s1_target_ho_st& s, const sta
       rrc_log->warning("The E-RAB Id=%d is not recognized\n", erab_item.erab_id);
       continue;
     }
-    const auto& drbs  = rrc_ue->bearer_list.get_pending_addmod_drbs();
+    const auto& drbs  = rrc_ue->bearer_list.get_established_drbs();
     uint8_t     drbid = erab_item.erab_id - 4;
     auto        drb_it =
         std::find_if(drbs.begin(), drbs.end(), [drbid](const drb_to_add_mod_s& drb) { return drb.drb_id == drbid; });
@@ -1363,7 +1366,6 @@ void rrc::ue::rrc_mobility::handle_crnti_ce(intraenb_ho_st& s, const user_crnti_
     rrc_enb->phy->set_config(rrc_ue->rnti, rrc_ue->phy_rrc_dedicated_list);
 
     rrc_ue->ue_security_cfg.regenerate_keys_handover(s.target_cell->cell_cfg.pci, s.target_cell->cell_cfg.dl_earfcn);
-    rrc_ue->bearer_list.reest_bearers();
     rrc_ue->apply_pdcp_srb_updates(rrc_ue->current_rr_cfg);
     rrc_ue->apply_pdcp_drb_updates(rrc_ue->current_rr_cfg);
   } else {

srsenb/src/stack/rrc/rrc_ue.cc

@@ -290,9 +290,6 @@ void rrc::ue::handle_rrc_con_setup_complete(rrc_conn_setup_complete_s* msg, srsl
   pdu->N_bytes = msg_r8->ded_info_nas.size();
   memcpy(pdu->msg, msg_r8->ded_info_nas.data(), pdu->N_bytes);
 
-  // Flag completion of RadioResource Configuration
-  bearer_list.rr_ded_cfg_complete();
-
   // Signal MAC scheduler that configuration was successful
   mac_ctrl->handle_con_setup_complete();
 
@@ -434,9 +431,6 @@ void rrc::ue::handle_rrc_con_reest_complete(rrc_conn_reest_complete_s* msg, srsl
   parent->gtpu->mod_bearer_rnti(old_reest_rnti, rnti);
   parent->s1ap->user_mod(old_reest_rnti, rnti);
 
-  // Flag completion of RadioResource Configuration
-  bearer_list.rr_ded_cfg_complete();
-
   // Signal MAC scheduler that configuration was successful
   mac_ctrl->handle_con_reest_complete();
 
@@ -604,7 +598,13 @@ void rrc::ue::send_connection_reconf_new_bearer()
   dl_dcch_msg.msg.c1().rrc_conn_recfg().rrc_transaction_id = (uint8_t)((transaction_id++) % 4);
   rrc_conn_recfg_r8_ies_s* conn_reconf = &dl_dcch_msg.msg.c1().rrc_conn_recfg().crit_exts.c1().rrc_conn_recfg_r8();
 
-  conn_reconf->rr_cfg_ded_present = bearer_list.fill_rr_cfg_ded(conn_reconf->rr_cfg_ded);
+  fill_rr_cfg_ded_reconf(conn_reconf->rr_cfg_ded,
+                         current_rr_cfg,
+                         parent->cfg,
+                         cell_ded_list,
+                         bearer_list,
+                         ue_capabilities,
+                         reconf_cause::other);
 
   // Setup new bearer
   apply_pdcp_srb_updates(conn_reconf->rr_cfg_ded);
@@ -616,6 +616,8 @@ void rrc::ue::send_connection_reconf_new_bearer()
   if (conn_reconf->rr_cfg_ded_present or conn_reconf->ded_info_nas_list_present) {
     send_dl_dcch(&dl_dcch_msg);
   }
+
+  apply_rr_cfg_ded_diff(current_rr_cfg, conn_reconf->rr_cfg_ded);
 }
 
 void rrc::ue::handle_rrc_reconf_complete(rrc_conn_recfg_complete_s* msg, srslte::unique_byte_buffer_t pdu)
@@ -624,9 +626,6 @@ void rrc::ue::handle_rrc_reconf_complete(rrc_conn_recfg_complete_s* msg, srslte:
   parent->phy->complete_config(rnti);
 
   if (last_rrc_conn_recfg.rrc_transaction_id == msg->rrc_transaction_id) {
-    // Flag completion of RadioResource Configuration
-    bearer_list.rr_ded_cfg_complete();
-
     // Activate SCells and bearers in the MAC scheduler that were advertised in the RRC Reconf message
     mac_ctrl->handle_con_reconf_complete();
 

srsenb/src/stack/rrc/ue_rr_cfg.cc

@@ -335,7 +335,7 @@ void fill_rr_cfg_ded_reconf(asn1::rrc::rr_cfg_ded_s&             rr_cfg,
 
   // Update DRBs if required
   srslte::compute_cfg_diff(current_rr_cfg.drb_to_add_mod_list,
-                           bearers.get_pending_addmod_drbs(),
+                           bearers.get_established_drbs(),
                            rr_cfg.drb_to_add_mod_list,
                            rr_cfg.drb_to_release_list);
   rr_cfg.drb_to_add_mod_list_present = rr_cfg.drb_to_add_mod_list.size() > 0;