nr,gnb,sched: avoid that the nr sched handles the rach before it creates the ue object

srsenb/hdr/stack/mac/nr/sched_nr.h

@@ -44,7 +44,7 @@ public:
   void ue_cfg(uint16_t rnti, const ue_cfg_t& cfg) override;
   void ue_rem(uint16_t rnti) override;
 
-  int dl_rach_info(uint32_t cc, const rar_info_t& rar_info);
+  int dl_rach_info(const rar_info_t& rar_info, const ue_cfg_t& uecfg);
 
   void dl_ack_info(uint16_t rnti, uint32_t cc, uint32_t pid, uint32_t tb_idx, bool ack) override;
   void ul_crc_info(uint16_t rnti, uint32_t cc, uint32_t pid, bool crc) override;
@@ -61,6 +61,7 @@ public:
 
 private:
   void ue_cfg_impl(uint16_t rnti, const ue_cfg_t& cfg);
+  bool add_ue_impl(uint16_t rnti, std::unique_ptr<sched_nr_impl::ue> u);
 
   // args
   sched_nr_impl::sched_params cfg;

srsenb/hdr/stack/mac/nr/sched_nr_worker.h

@@ -67,6 +67,8 @@ public:
 
   explicit cc_worker(const cell_params_t& params);
 
+  void dl_rach_info(const sched_nr_interface::rar_info_t& rar_info);
+
   void run_slot(slot_point pdcch_slot, ue_map_t& ue_db_, dl_sched_res_t& dl_res, ul_sched_t& ul_res);
 
   // const params

srsenb/src/stack/mac/nr/mac_nr.cc

@@ -161,7 +161,7 @@ void mac_nr::rach_detected(const rach_info_t& rach_info)
     sched_nr_ue_cfg_t uecfg = {};
     uecfg.carriers.resize(1);
     uecfg.carriers[0].active      = true;
-    uecfg.carriers[0].cc          = 0;
+    uecfg.carriers[0].cc          = enb_cc_idx;
     uecfg.ue_bearers[0].direction = mac_lc_ch_cfg_t::BOTH;
     srsran::phy_cfg_nr_default_t::reference_cfg_t ref_args{};
     ref_args.duplex = cell_config[0].duplex.mode == SRSRAN_DUPLEX_MODE_TDD
@@ -170,7 +170,7 @@ void mac_nr::rach_detected(const rach_info_t& rach_info)
     uecfg.phy_cfg     = srsran::phy_cfg_nr_default_t{ref_args};
     uecfg.phy_cfg.csi = {}; // disable CSI until RA is complete
 
-    uint16_t rnti = reserve_rnti(enb_cc_idx, uecfg);
+    uint16_t rnti = alloc_ue(enb_cc_idx);
 
     // Log this event.
     ++detected_rachs[enb_cc_idx];
@@ -182,7 +182,7 @@ void mac_nr::rach_detected(const rach_info_t& rach_info)
     rar_info.ta_cmd                                 = rach_info.time_adv;
     rar_info.prach_slot                             = slot_point{NUMEROLOGY_IDX, rach_info.slot_index};
     // TODO: fill remaining fields as required
-    sched->dl_rach_info(enb_cc_idx, rar_info);
+    sched->dl_rach_info(rar_info, uecfg);
     rrc->add_user(rnti, uecfg);
 
     logger.info("RACH:  slot=%d, cc=%d, preamble=%d, offset=%d, temp_crnti=0x%x",

srsenb/src/stack/mac/nr/sched_nr.cc

@@ -15,6 +15,7 @@
 #include "srsenb/hdr/stack/mac/nr/harq_softbuffer.h"
 #include "srsenb/hdr/stack/mac/nr/sched_nr_bwp.h"
 #include "srsenb/hdr/stack/mac/nr/sched_nr_worker.h"
+#include "srsran/common/phy_cfg_nr_default.h"
 #include "srsran/common/string_helpers.h"
 #include "srsran/common/thread_pool.h"
 
@@ -87,12 +88,15 @@ class sched_nr::common_event_manager
 public:
   explicit common_event_manager(srslog::basic_logger& logger_) : logger(logger_) {}
 
+  /// Enqueue an event that does not map into a ue method (e.g. rem_user, add_user)
   void enqueue_event(const char* event_name, srsran::move_callback<void()> ev, uint16_t rnti = SRSRAN_INVALID_RNTI)
   {
     std::lock_guard<std::mutex> lock(event_mutex);
     next_slot_events.emplace_back(rnti, event_name, std::move(ev));
   }
 
+  /// Enqueue an event that directly maps into a ue method (e.g. ul_sr_info, ul_bsr, etc.)
+  /// Note: these events can be processed sequentially or in parallel, depending on whether the UE supports CA
   template <typename R, typename... FmtArgs>
   void enqueue_ue_event(uint16_t rnti, R (ue::*ue_action)(FmtArgs...), const char* fmt_str, FmtArgs... args)
   {
@@ -111,7 +115,7 @@ public:
     next_slot_ue_events.emplace_back(rnti, std::move(callback));
   }
 
-  /// Process events synchronized during slot_indication() that are directed at CA-enabled UEs
+  /// Process all events that are directed at CA-enabled UEs
   /// Note: non-CA UEs are updated later in get_dl_sched, to leverage parallelism
   void process_common(ue_map_t& ues)
   {
@@ -146,7 +150,7 @@ public:
   }
 
   /// Process events synchronized during slot_indication() that are directed at non CA-enabled UEs
-  void process_carrier_events(ue_map_t& ues, uint32_t cc)
+  void process_single_cc_ue_events(ue_map_t& ues, uint32_t cc)
   {
     for (ue_event_t& ev : current_slot_ue_events) {
       if (ev.rnti == SRSRAN_INVALID_RNTI) {
@@ -190,7 +194,9 @@ private:
       fmt::format_to(fmtbuf, "}}");
       prefix = ", ";
     }
-    logger.debug("SCHED: Pending slot events: [%s%s]", srsran::to_c_str(common_fmtbuf), srsran::to_c_str(fmtbuf));
+    if (common_fmtbuf.size() > 0 or fmtbuf.size() > 0) {
+      logger.debug("SCHED: Pending slot events: [%s%s]", srsran::to_c_str(common_fmtbuf), srsran::to_c_str(fmtbuf));
+    }
   }
 
   srslog::basic_logger& logger;
@@ -306,6 +312,7 @@ int sched_nr::config(const sched_args_t& sched_cfg, srsran::const_span<cell_cfg_
 void sched_nr::ue_cfg(uint16_t rnti, const ue_cfg_t& uecfg)
 {
   srsran_assert(assert_ue_cfg_valid(rnti, uecfg) == SRSRAN_SUCCESS, "Invalid UE configuration");
+  logger->info("SCHED: New user rnti=0x%x, cc=%d", rnti, cfg.cells[0].cc);
   pending_events->enqueue_event(
       "ue_cfg", [this, rnti, uecfg]() { ue_cfg_impl(rnti, uecfg); }, rnti);
 }
@@ -316,14 +323,20 @@ void sched_nr::ue_rem(uint16_t rnti)
       "ue_rem", [this, rnti]() { ue_db.erase(rnti); }, rnti);
 }
 
+bool sched_nr::add_ue_impl(uint16_t rnti, std::unique_ptr<sched_nr_impl::ue> u)
+{
+  auto ret = ue_db.insert(rnti, std::move(u));
+  if (not ret.has_value()) {
+    logger->error("SCHED: Failed to create new user rnti=0x%x", rnti);
+    return false;
+  }
+  return true;
+}
+
 void sched_nr::ue_cfg_impl(uint16_t rnti, const ue_cfg_t& uecfg)
 {
   if (not ue_db.contains(rnti)) {
-    logger->info("SCHED: New user rnti=0x%x, cc=%d", rnti, cfg.cells[0].cc);
-    auto ret = ue_db.insert(rnti, std::unique_ptr<ue>(new ue{rnti, uecfg, cfg}));
-    if (not ret.has_value()) {
-      logger->error("SCHED: Failed to create new user rnti=0x%x", rnti);
-    }
+    add_ue_impl(rnti, std::unique_ptr<ue>(new ue{rnti, uecfg, cfg}));
   } else {
     ue_db[rnti]->set_cfg(uecfg);
   }
@@ -363,7 +376,7 @@ int sched_nr::get_dl_sched(slot_point pdsch_tti, uint32_t cc, dl_res_t& result)
   ul_res_t& ul_res = pending_results->add_ul_result(pdsch_tti, cc);
 
   // process non-cc specific feedback if pending (e.g. SRs, buffer state updates, UE config) for non-CA UEs
-  pending_events->process_carrier_events(ue_db, cc);
+  pending_events->process_single_cc_ue_events(ue_db, cc);
 
   // prepare non-CA UEs internal state for new slot
   for (auto& u : ue_db) {
@@ -405,10 +418,24 @@ void sched_nr::get_metrics(mac_metrics_t& metrics)
   metrics_handler->get_metrics(metrics);
 }
 
-int sched_nr::dl_rach_info(uint32_t cc, const rar_info_t& rar_info)
+int sched_nr::dl_rach_info(const rar_info_t& rar_info, const ue_cfg_t& uecfg)
 {
-  cc_workers[cc]->pending_feedback.enqueue_common_event(
-      [this, cc, rar_info]() { cc_workers[cc]->bwps[0].ra.dl_rach_info(rar_info); });
+  // enqueue UE creation event + RACH handling
+  auto add_ue = [this, uecfg, rar_info]() {
+    // create user
+    // Note: UEs being created in sched main thread, which has higher priority
+    logger->info("SCHED: New user rnti=0x%x, cc=%d", rar_info.temp_crnti, uecfg.carriers[0].cc);
+    std::unique_ptr<ue> u{new ue{rar_info.temp_crnti, uecfg, cfg}};
+
+    uint16_t rnti = rar_info.temp_crnti;
+    if (add_ue_impl(rnti, std::move(u))) {
+      // RACH is handled in cc worker, once the UE object is created and inserted in the ue_db
+      uint32_t cc = uecfg.carriers[0].cc;
+      cc_workers[cc]->pending_feedback.enqueue_common_event(
+          [this, cc, rar_info]() { cc_workers[cc]->dl_rach_info(rar_info); });
+    }
+  };
+  pending_events->enqueue_event("dl_rach_info", add_ue);
   return SRSRAN_SUCCESS;
 }
 

srsenb/src/stack/mac/nr/sched_nr_worker.cc

@@ -91,6 +91,11 @@ bool cc_worker::save_sched_result(dl_sched_res_t& dl_res, ul_sched_t& ul_res, sl
   return true;
 }
 
+void cc_worker::dl_rach_info(const sched_nr_interface::rar_info_t& rar_info)
+{
+  bwps[0].ra.dl_rach_info(rar_info);
+}
+
 /// Called within a locked context, to generate {slot, cc} scheduling decision
 void cc_worker::run_slot(slot_point pdcch_slot, ue_map_t& ue_db, dl_sched_res_t& dl_res, ul_sched_t& ul_res)
 {

srsenb/test/mac/nr/sched_nr_sim_ue.cc

@@ -146,7 +146,6 @@ int sched_nr_base_tester::add_user(uint16_t                            rnti,
                                    uint32_t                            preamble_idx)
 {
   sem_wait(&slot_sem);
-  sched_ptr->ue_cfg(rnti, ue_cfg_);
 
   TESTASSERT(ue_db.count(rnti) == 0);
 
@@ -157,7 +156,7 @@ int sched_nr_base_tester::add_user(uint16_t                            rnti,
   rach_info.prach_slot   = tti_rx;
   rach_info.preamble_idx = preamble_idx;
   rach_info.msg3_size    = 7;
-  sched_ptr->dl_rach_info(ue_cfg_.carriers[0].cc, rach_info);
+  sched_ptr->dl_rach_info(rach_info, ue_cfg_);
 
   sem_post(&slot_sem);