Schedule SRS longer in advance, cleanup

Schedule SRS longer in advance, so that it would also be enough even
with big k2 for UL TDA.

Remove useless types: we do not use the information on sched_srs
anymore, so remove it.

Check that the VRB map is free before making allocations.

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c

@@ -2766,8 +2766,6 @@ bool add_connected_nr_ue(gNB_MAC_INST *nr_mac, NR_UE_info_t *UE)
 
   NR_UE_sched_ctrl_t *sched_ctrl = &UE->UE_sched_ctrl;
   sched_ctrl->dl_max_mcs = 28; /* do not limit MCS for individual UEs */
-  sched_ctrl->sched_srs.frame = -1;
-  sched_ctrl->sched_srs.slot = -1;
   sched_ctrl->pdcch_cl_adjust = 0;
   reset_srs_stats(UE);
 

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_srs.c

@@ -471,9 +471,13 @@ static void nr_configure_srs(gNB_MAC_INST *nrmac,
   NR_beam_alloc_t beam = beam_allocation_procedure(&nrmac->beam_info, frame, slot, UE->UE_beam_index, slots_per_frame);
   AssertFatal(beam.idx >= 0, "Cannot allocate SRS in any available beam\n");
   uint16_t *vrb_map_UL = &nrmac->common_channels[CC_id].vrb_map_UL[beam.idx][buffer_index * MAX_BWP_SIZE];
-  uint64_t mask = SL_to_bitmap(srs_pdu->time_start_position, srs_pdu->num_symbols);
-  for (int i = 0; i < srs_pdu->bwp_size; ++i)
-    vrb_map_UL[i + srs_pdu->bwp_start] |= mask;
+  uint16_t mask = SL_to_bitmap(srs_pdu->time_start_position, srs_pdu->num_symbols);
+  for (int i = 0; i < srs_pdu->bwp_size; ++i) {
+    int rb = i + srs_pdu->bwp_start;
+    uint16_t alloc = vrb_map_UL[rb] & mask;
+    AssertFatal(nrmac->ulprbbl[rb] != 0 || alloc == 0, "RB %d not free for SRS: alloc 0x%02x for mask 0x%02x\n", rb, alloc, mask);
+    vrb_map_UL[rb] |= mask;
+  }
 }
 
 static void nr_fill_nfapi_srs(gNB_MAC_INST *nrmac,
@@ -512,9 +516,7 @@ static void nr_fill_nfapi_srs(gNB_MAC_INST *nrmac,
 *********************************************************************/
 void nr_schedule_srs(int module_id, frame_t frame, int slot)
  {
-  const int CC_id = 0;
   gNB_MAC_INST *nrmac = RC.nrmac[module_id];
-  const NR_ServingCellConfigCommon_t *scc = nrmac->common_channels[CC_id].ServingCellConfigCommon;
 
   /* already mutex protected: held in gNB_dlsch_ulsch_scheduler() */
   NR_SCHED_ENSURE_LOCKED(&nrmac->sched_lock);
@@ -526,12 +528,6 @@ void nr_schedule_srs(int module_id, frame_t frame, int slot)
     NR_UE_sched_ctrl_t *sched_ctrl = &UE->UE_sched_ctrl;
     NR_UE_UL_BWP_t *current_BWP = &UE->current_UL_BWP;
 
-    if(sched_ctrl->sched_srs.srs_scheduled && sched_ctrl->sched_srs.frame == frame && sched_ctrl->sched_srs.slot == slot) {
-      sched_ctrl->sched_srs.frame = -1;
-      sched_ctrl->sched_srs.slot = -1;
-      sched_ctrl->sched_srs.srs_scheduled = false;
-    }
-
     if ((sched_ctrl->ul_failure && !get_softmodem_params()->phy_test) || nr_timer_is_active(&sched_ctrl->transm_interrupt)) {
       continue;
     }
@@ -566,34 +562,20 @@ void nr_schedule_srs(int module_id, frame_t frame, int slot)
         continue;
       }
 
-      NR_PUSCH_TimeDomainResourceAllocationList_t *tdaList = get_ul_tdalist(current_BWP,
-                                                                            sched_ctrl->coreset->controlResourceSetId,
-                                                                            sched_ctrl->search_space->searchSpaceType->present,
-                                                                            TYPE_C_RNTI_);
-      const int num_tda = tdaList->list.count;
-      int max_k2 = 0;
-      // avoid last one in the list (for msg3)
-      for (int i = 0; i < num_tda - 1; i++) {
-        int k2 = get_K2(tdaList, i, current_BWP->scs, scc);
-        max_k2 = k2 > max_k2 ? k2 : max_k2;
-      }
-
       // we are sheduling SRS max_k2 slot in advance for the presence of SRS to be taken into account when scheduling PUSCH
       const int n_slots_frame = nrmac->frame_structure.numb_slots_frame;
-      const int sched_slot = (slot + max_k2) % n_slots_frame;
-      const int sched_frame = (frame + (slot + max_k2) / n_slots_frame) % MAX_FRAME_NUMBER;
+      const int n_ahead = n_slots_frame - 1 + get_NTN_Koffset(nrmac->common_channels[0].ServingCellConfigCommon);
+      const int sched_slot = (slot + n_ahead) % n_slots_frame;
+      const int sched_frame = (frame + (slot + n_ahead) / n_slots_frame) % MAX_FRAME_NUMBER;
 
       const uint16_t period = srs_period[srs_resource->resourceType.choice.periodic->periodicityAndOffset_p.present];
       const uint16_t offset = get_nr_srs_offset(srs_resource->resourceType.choice.periodic->periodicityAndOffset_p);
 
       // Check if UE will transmit the SRS in this frame
-      if ((sched_frame * n_slots_frame + sched_slot - offset) % period == 0) {
-        LOG_D(NR_MAC," %d.%d Scheduling SRS reception for %d.%d\n", frame, slot, sched_frame, sched_slot);
-        nr_fill_nfapi_srs(nrmac, CC_id, UE, sched_frame, sched_slot, srs_resource_set, srs_resource);
-        sched_ctrl->sched_srs.frame = sched_frame;
-        sched_ctrl->sched_srs.slot = sched_slot;
-        sched_ctrl->sched_srs.srs_scheduled = true;
-      }
+      if ((sched_frame * n_slots_frame + sched_slot - offset) % period != 0)
+        continue;
+      LOG_D(NR_MAC," %d.%d Scheduling SRS reception for %d.%d\n", frame, slot, sched_frame, sched_slot);
+      nr_fill_nfapi_srs(nrmac, CC_id, UE, sched_frame, sched_slot, srs_resource_set, srs_resource);
     }
   }
 }

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c

@@ -1585,25 +1585,6 @@ void handle_nr_srs_measurements(const module_id_t module_id,
   NR_SCHED_UNLOCK(&nrmac->sched_lock);
 }
 
-long get_K2(NR_PUSCH_TimeDomainResourceAllocationList_t *tdaList,
-            int time_domain_assignment,
-            int mu,
-            const NR_ServingCellConfigCommon_t *scc)
-{
-  /* we assume that this function is mutex-protected from outside */
-  NR_PUSCH_TimeDomainResourceAllocation_t *tda = tdaList->list.array[time_domain_assignment];
-  const int NTN_gNB_Koffset = get_NTN_Koffset(scc);
-
-  if (tda->k2)
-    return *tda->k2 + NTN_gNB_Koffset;
-  else if (mu < 2)
-    return 1 + NTN_gNB_Koffset;
-  else if (mu == 2)
-    return 2 + NTN_gNB_Koffset;
-  else
-    return 3 + NTN_gNB_Koffset;
-}
-
 static bool nr_UE_is_to_be_scheduled(const frame_structure_t *fs,
                                      NR_UE_info_t *UE,
                                      frame_t frame,

openair2/LAYER2/NR_MAC_gNB/mac_proto.h

@@ -286,11 +286,6 @@ NR_ControlResourceSet_t *get_coreset(gNB_MAC_INST *nrmac,
                                      NR_BWP_DownlinkDedicated_t *bwp_dedicated,
                                      NR_ControlResourceSetId_t coreset_id);
 
-long get_K2(NR_PUSCH_TimeDomainResourceAllocationList_t *tdaList,
-            int time_domain_assignment,
-            int mu,
-            const NR_ServingCellConfigCommon_t *scc);
-
 const NR_DMRS_UplinkConfig_t *get_DMRS_UplinkConfig(const NR_PUSCH_Config_t *pusch_Config, const NR_tda_info_t *tda_info);
 
 NR_pusch_dmrs_t get_ul_dmrs_params(const NR_ServingCellConfigCommon_t *scc,

openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h

@@ -429,12 +429,6 @@ typedef struct NR_sched_pusch {
   int phr_txpower_calc;
 } NR_sched_pusch_t;
 
-typedef struct NR_sched_srs {
-  int frame;
-  int slot;
-  bool srs_scheduled;
-} NR_sched_srs_t;
-
 typedef struct NR_pdsch_dmrs {
   uint8_t dmrs_ports_id;
   uint8_t N_PRB_DMRS;
@@ -599,9 +593,6 @@ typedef struct {
   NR_sched_pucch_t *sched_pucch;
   int sched_pucch_size;
 
-  /// Sched SRS: scheduling decisions
-  NR_sched_srs_t sched_srs;
-
   /// uplink bytes that are currently scheduled
   int sched_ul_bytes;
   /// estimation of the UL buffer size