sched: use search space 1 when not in fallback mode

Author: herlesupreeth

lib/scheduler/ue_scheduling/ue_cell.cpp

@@ -198,19 +198,6 @@ get_prioritized_search_spaces(const ue_cell&        ue_cc,
 {
   static_vector<const search_space_info*, MAX_NOF_SEARCH_SPACE_PER_BWP> active_search_spaces;
 
-  // Case of retransmission of HARQ scheduled using fallback DCI format.
-  // As per TS 38.213, the UE monitors PDCCH candidates for DCI format 0_0 and DCI format 1_0 with CRC scrambled by the
-  // C-RNTI, the MCS-C-RNTI, or the CS-RNTI in the one or more search space sets in a slot where the UE monitors PDCCH
-  // candidates for at least a DCI format 0_0 or a DCI format 1_0 with CRC scrambled by SI-RNTI, RA-RNTI or P-RNTI.
-  if (dci_type.has_value() and
-      ((is_dl and static_cast<dci_dl_rnti_config_type>(dci_type.value()) == dci_dl_rnti_config_type::c_rnti_f1_0) or
-       (not is_dl and
-        static_cast<dci_ul_rnti_config_type>(dci_type.value()) == dci_ul_rnti_config_type::c_rnti_f0_0))) {
-    for (const auto ss_id : ue_cc.cfg().get_sib1_other_si_ra_pg_ss_ids()) {
-      active_search_spaces.push_back(&ue_cc.cfg().search_space(ss_id));
-    }
-  }
-
   // Get all Search Spaces configured in PDCCH-Config for active BWP.
   // See TS 38.213, A UE monitors PDCCH candidates in one or more of the following search spaces sets:
   // - a Type3-PDCCH CSS set configured by SearchSpace in PDCCH-Config with searchSpaceType = common for DCI formats
@@ -226,6 +213,22 @@ get_prioritized_search_spaces(const ue_cell&        ue_cc,
     }
   }
 
+  // As per TS 38.213, the UE monitors PDCCH candidates for DCI format 0_0 and DCI format 1_0 with CRC scrambled by the
+  // C-RNTI, the MCS-C-RNTI, or the CS-RNTI in the one or more search space sets in a slot where the UE monitors PDCCH
+  // candidates for at least a DCI format 0_0 or a DCI format 1_0 with CRC scrambled by SI-RNTI, RA-RNTI or P-RNTI.
+  // [Implementation-defined] We exclude SearchSpace#0 to avoid the complexity of computing the SearchSpace#0 PDCCH
+  // candidates monitoring occasions associated with a SS/PBCH block as mentioned in TS 38.213, clause 10.1.
+  if (ue_cc.cfg().cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.ra_search_space_id != to_search_space_id(0)) {
+    active_search_spaces.push_back(&ue_cc.cfg().search_space(
+        ue_cc.cfg().cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.ra_search_space_id));
+  }
+  if (ue_cc.cfg().cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.paging_search_space_id.has_value() and
+      ue_cc.cfg().cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.paging_search_space_id.value() !=
+          to_search_space_id(0)) {
+    active_search_spaces.push_back(&ue_cc.cfg().search_space(
+        ue_cc.cfg().cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.paging_search_space_id.value()));
+  }
+
   // Sort search spaces by priority.
   auto sort_ss = [&ue_cc, is_dl](const search_space_info* lhs, const search_space_info* rhs) {
     // NOTE: It does not matter whether we use lhs or rhs SearchSpace to get the aggregation level as we are sorting not

lib/scheduler/ue_scheduling/ue_configuration.cpp

@@ -573,14 +573,6 @@ ue_cell_configuration::ue_cell_configuration(rnti_t                     crnti_,
 {
   // Apply UE-dedicated Config.
   reconfigure(serv_cell_cfg_);
-
-  std::set<search_space_id> ss_id_set;
-  ss_id_set.emplace(cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.sib1_search_space_id);
-  ss_id_set.emplace(cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.ra_search_space_id);
-  if (cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.paging_search_space_id.has_value()) {
-    ss_id_set.emplace(cell_cfg_common.dl_cfg_common.init_dl_bwp.pdcch_common.paging_search_space_id.value());
-  }
-  sib1_other_si_ra_pg_ss_ids.assign(ss_id_set.begin(), ss_id_set.end());
 }
 
 void ue_cell_configuration::reconfigure(const serving_cell_config& cell_cfg_ded_req)

lib/scheduler/ue_scheduling/ue_configuration.h

@@ -17,7 +17,6 @@
 #include "srsran/ran/pdcch/cce_to_prb_mapping.h"
 #include "srsran/ran/pdcch/pdcch_candidates.h"
 #include "srsran/scheduler/config/bwp_configuration.h"
-#include <set>
 
 namespace srsran {
 
@@ -139,10 +138,6 @@ class ue_cell_configuration
   /// Get the number of active DL ports for this UE.
   unsigned get_nof_dl_ports() const { return nof_dl_ports; }
 
-  /// Get the ids of search space sets where the UE monitors PDCCH candidates for DCI with CRC scrambled by SI-RNTI,
-  /// RA-RNTI and P-RNTI.
-  span<const search_space_id> get_sib1_other_si_ra_pg_ss_ids() const { return sib1_other_si_ra_pg_ss_ids; }
-
 private:
   void configure_bwp_common_cfg(bwp_id_t bwpid, const bwp_downlink_common& bwp_dl_common);
   void configure_bwp_common_cfg(bwp_id_t bwpid, const bwp_uplink_common& bwp_ul_common);
@@ -168,10 +163,6 @@ class ue_cell_configuration
 
   /// Number of DL ports for this UE.
   unsigned nof_dl_ports = 1;
-
-  /// Ids of search space sets where the UE monitors PDCCH candidates for DCI with CRC scrambled by SI-RNTI, RA-RNTI and
-  /// P-RNTI.
-  std::vector<search_space_id> sib1_other_si_ra_pg_ss_ids;
 };
 
 } // namespace srsran