Extension to PF algorithm based on qos flow priorities

openair2/LAYER2/NR_MAC_gNB/config.c

@@ -29,6 +29,7 @@
  * @ingroup _mac
 
  */
+#define _GNU_SOURCE
 
 #include "common/platform_types.h"
 #include "common/platform_constants.h"
@@ -55,6 +56,65 @@ extern RAN_CONTEXT_t RC;
 //extern int l2_init_gNB(void);
 extern uint8_t nfapi_mode;
 
+/**
+ * This is a QoS comparator function for qsort.
+ *
+ * @lcid1 pointer to the first array element
+ * @lcid1 pointer to the second array element
+ * @return negative return value means that *p1 goes before *p2
+ *         zero return value means that that *p1 is equivalent to *p2
+ *         positive return value means that *p1 goes after *p2
+ **/
+static int QoS_Comp(const void *lcid1, const void *lcid2, void *sctrl)
+{
+  NR_UE_sched_ctrl_t *sched_ctrl = (NR_UE_sched_ctrl_t *)sctrl;
+  uint8_t lcid_1 = *(uint8_t *)lcid1;
+  uint8_t lcid_2 = *(uint8_t *)lcid2;
+  uint8_t *lc_priority = sched_ctrl->dl_lc_ids_priorities;
+
+  int32_t priority_1 = lc_priority[lcid_1];
+  int32_t priority_2 = lc_priority[lcid_2];
+
+  return (priority_1 - priority_2);
+}
+
+void process_lcOrder(NR_UE_sched_ctrl_t *sched_ctrl)
+{
+  // Reset the priority of the UE
+  sched_ctrl->priority_ue = 0;
+  for (int i = 0; i < sched_ctrl->dl_lc_num; i++) {
+    uint8_t lcid = sched_ctrl->dl_lc_ids[i];
+    if (lcid < 4) {
+      /* each SRB is considered a priority of 1 */
+      sched_ctrl->dl_lc_ids_priorities[lcid] = 1;
+    } else {
+      /* sum of priorities of qos flows mapped to a DRB/LC */
+      uint8_t drb_id = lcid - 3; /* DRBID is LCID - 3 */
+      for (int q = 0; q < NR_MAX_NUM_QFI; q++)
+        sched_ctrl->dl_lc_ids_priorities[lcid] += sched_ctrl->qos_config[drb_id - 1][q].priority;
+    }
+    sched_ctrl->priority_ue += sched_ctrl->dl_lc_ids_priorities[lcid];
+    LOG_D(NR_MAC,
+          "The priority of the UE with lcid %d of priority %d is %d\n",
+          lcid,
+          sched_ctrl->dl_lc_ids_priorities[lcid],
+          sched_ctrl->priority_ue);
+  }
+
+  /* lc with in each UE are sorted so that lower in value(high priority) lcs are scheduled first*/
+  qsort_r(sched_ctrl->dl_lc_ids, sched_ctrl->dl_lc_num, sizeof(uint8_t), QoS_Comp, sched_ctrl->dl_lc_ids_priorities);
+
+  LOG_I(NR_MAC, "Printing logical channel ids sorted by Priority Level:\n");
+  for (int j = 0; j < sched_ctrl->dl_lc_num; j++) {
+    uint8_t lcid = sched_ctrl->dl_lc_ids[j];
+    LOG_I(NR_MAC,
+          "LCID %d (%s %d)\n",
+          lcid,
+          lcid < 4 ? "SRB" : "DRB",
+          lcid < 4 ? lcid : lcid - 3); // lcid 0 - SRB0, 1- SRB1, 2 - SRB2, 3 - 31 DRBs,
+  }
+}
+
 static void process_rlcBearerConfig(struct NR_CellGroupConfig__rlc_BearerToAddModList *rlc_bearer2add_list,
                                     struct NR_CellGroupConfig__rlc_BearerToReleaseList *rlc_bearer2release_list,
                                     NR_UE_sched_ctrl_t *sched_ctrl)
@@ -120,6 +180,7 @@ void process_CellGroup(NR_CellGroupConfig_t *CellGroup, NR_UE_info_t *UE)
     nr_mac_prepare_ra_ue(RC.nrmac[0], UE->rnti, CellGroup);
    }
    process_rlcBearerConfig(CellGroup->rlc_BearerToAddModList, CellGroup->rlc_BearerToReleaseList, &UE->UE_sched_ctrl);
+   process_lcOrder(&UE->UE_sched_ctrl);
 }
 
 static void config_common(gNB_MAC_INST *nrmac, int pdsch_AntennaPorts, int pusch_AntennaPorts, NR_ServingCellConfigCommon_t *scc)

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_dlsch.c

@@ -653,6 +653,9 @@ static void pf_dl(module_id_t module_id,
       if (sched_ctrl->num_total_bytes == 0 && frame != (sched_ctrl->ta_frame + 10) % 1024)
         continue;
 
+      /* QoS processing*/
+      uint8_t aggregated_priority = sched_ctrl->priority_ue;
+
       /* Calculate coeff */
       const NR_bler_options_t *bo = &mac->dl_bler;
       const int max_mcs_table = current_BWP->mcsTableIdx == 1 ? 27 : 28;
@@ -674,14 +677,16 @@ static void pf_dl(module_id_t module_id,
                                     0 /* N_PRB_oh, 0 for initialBWP */,
                                     0 /* tb_scaling */,
                                     sched_pdsch->nrOfLayers) >> 3;
-      float coeff_ue = (float) tbs / UE->dl_thr_ue;
-      LOG_D(NR_MAC, "[UE %04x][%4d.%2d] b %d, thr_ue %f, tbs %d, coeff_ue %f\n",
+      float coeff_ue = (float)tbs / (UE->dl_thr_ue * aggregated_priority);
+      LOG_D(NR_MAC,
+            "[UE %04x][%4d.%2d] b %d, thr_ue %f, tbs %d, ue_priority %d, coeff_ue %f\n",
             UE->rnti,
             frame,
             slot,
             b,
             UE->dl_thr_ue,
             tbs,
+            aggregated_priority,
             coeff_ue);
       /* Create UE_sched list for UEs eligible for new transmission*/
       UE_sched[curUE].coef=coeff_ue;

openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c

@@ -252,7 +252,7 @@ static void set_QoSConfig(const f1ap_ue_context_modif_req_t *req, NR_UE_sched_ct
   AssertFatal(req != NULL, "f1ap_ue_context_modif_req is NULL\n");
   uint8_t drb_count = req->drbs_to_be_setup_length;
   uint8_t srb_count = req->srbs_to_be_setup_length;
-  LOG_I(NR_MAC, "Number of DRBs = %d and SRBs = %d\n", drb_count, srb_count);
+  LOG_D(NR_MAC, "Number of DRBs = %d and SRBs = %d\n", drb_count, srb_count);
 
   /* DRBs*/
   for (int i = 0; i < drb_count; i++) {
@@ -272,7 +272,7 @@ static void set_QoSConfig(const f1ap_ue_context_modif_req_t *req, NR_UE_sched_ct
         fiveqi = qos_char->dynamic.fiveqi > 0 ? qos_char->dynamic.fiveqi : 0;
       }
       if (qos_char->qos_type == non_dynamic) {
-        LOG_D(NR_MAC, "Qos Priority level is considered from the standarsdized 5QI to QoS mapping table\n");
+        LOG_I(NR_MAC, "Qos Priority level is considered from the standarsdized 5QI to QoS mapping table\n");
         for (int id = 0; id < 26; id++) {
           if (qos_fiveqi[id] == fiveqi)
             priority = qos_priority[id];
@@ -280,7 +280,7 @@ static void set_QoSConfig(const f1ap_ue_context_modif_req_t *req, NR_UE_sched_ct
       }
       sched_ctrl->qos_config[drb_id - 1][q].fiveQI = fiveqi;
       sched_ctrl->qos_config[drb_id - 1][q].priority = priority;
-      LOG_D(NR_MAC,
+      LOG_I(NR_MAC,
             "In %s: drb_id %ld: 5QI %lu priority %lu\n",
             __func__,
             drb_id,
@@ -353,12 +353,12 @@ void ue_context_setup_request(const f1ap_ue_context_setup_t *req)
   AssertFatal(enc_rval.encoded > 0, "Could not encode CellGroup, failed element %s\n", enc_rval.failed_type->name);
   resp.du_to_cu_rrc_information->cellGroupConfig_length = (enc_rval.encoded + 7) >> 3;
 
-  /* TODO: need to apply after UE context reconfiguration confirmed? */
-  nr_mac_prepare_cellgroup_update(mac, UE, new_CellGroup);
-
   /* Fill the QoS config in MAC for each active DRB */
   set_QoSConfig(req, &UE->UE_sched_ctrl);
 
+  /* TODO: need to apply after UE context reconfiguration confirmed? */
+  nr_mac_prepare_cellgroup_update(mac, UE, new_CellGroup);
+
   /* Set NSSAI config in MAC for each active DRB */
   set_nssaiConfig(req->drbs_to_be_setup_length, req->drbs_to_be_setup, &UE->UE_sched_ctrl);
 
@@ -457,11 +457,11 @@ void ue_context_modification_request(const f1ap_ue_context_modif_req_t *req)
     AssertFatal(enc_rval.encoded > 0, "Could not encode CellGroup, failed element %s\n", enc_rval.failed_type->name);
     resp.du_to_cu_rrc_information->cellGroupConfig_length = (enc_rval.encoded + 7) >> 3;
 
-    nr_mac_prepare_cellgroup_update(mac, UE, new_CellGroup);
-
     /* Fill the QoS config in MAC for each active DRB */
     set_QoSConfig(req, &UE->UE_sched_ctrl);
 
+    nr_mac_prepare_cellgroup_update(mac, UE, new_CellGroup);
+
     /* Set NSSAI config in MAC for each active DRB */
     set_nssaiConfig(req->drbs_to_be_setup_length, req->drbs_to_be_setup, &UE->UE_sched_ctrl);
   } else {

openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h

@@ -634,6 +634,8 @@ typedef struct {
   uint8_t dl_lc_num;
   /// order in which DLSCH scheduler should allocate LCs
   uint8_t dl_lc_ids[NR_MAX_NUM_LCID];
+  // priorities of lcids
+  uint8_t dl_lc_ids_priorities[NR_MAX_NUM_LCID];
 
   /// Timer for RRC processing procedures
   uint32_t rrc_processing_timer;
@@ -642,8 +644,15 @@ typedef struct {
   nr_srs_feedback_t srs_feedback;
   nssai_t dl_lc_nssai[NR_MAX_NUM_LCID];
 
-  // Information about the QoS configuration for each LCID/DRB
-  NR_QoS_config_t qos_config[NR_MAX_NUM_LCID - 4][NR_MAX_NUM_QFI]; // 0 -CCCH and 1- 3 SRBs(0,1,2)
+  /*
+   Information about the QoS configuration for each LCID/DRB
+   (0 -CCCH and 1- 3 SRBs(0,1,2), 4-32 DRBs(0, 1, 28))
+    DRB Identity can be any value [1-32]
+  */
+  NR_QoS_config_t qos_config[NR_MAX_NUM_LCID][NR_MAX_NUM_QFI];
+
+  // priority assigned to ue
+  uint8_t priority_ue;
 } NR_UE_sched_ctrl_t;
 
 typedef struct {