sched,nr: added logic to update UE DL and UL buffer status

srsenb/hdr/stack/mac/common/ue_buffer_manager.h

@@ -70,6 +70,7 @@ public:
   // UL BSR methods
   bool                                 is_lcg_active(uint32_t lcg) const;
   int                                  get_bsr(uint32_t lcg) const;
+  int                                  get_bsr() const;
   const std::array<int, MAX_NOF_LCGS>& get_bsr_state() const { return lcg_bsr; }
 
   static bool is_lcid_valid(uint32_t lcid) { return lcid <= MAX_LC_ID; }

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

@@ -46,6 +46,8 @@ public:
   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;
   void ul_sr_info(slot_point slot_rx, uint16_t rnti) override;
+  void ul_bsr(uint16_t rnti, uint32_t lcg_id, uint32_t bsr);
+  void dl_buffer_state(uint16_t rnti, uint32_t lcid, uint32_t newtx, uint32_t retx);
 
   int get_dl_sched(slot_point pdsch_tti, uint32_t cc, dl_sched_res_t& result) override;
   int get_ul_sched(slot_point pusch_tti, uint32_t cc, ul_sched_t& result) override;

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

@@ -27,6 +27,10 @@ namespace sched_nr_impl {
 
 const static size_t MAX_GRANTS = sched_nr_interface::MAX_GRANTS;
 
+using pdcch_dl_t      = mac_interface_phy_nr::pdcch_dl_t;
+using pdcch_ul_t      = mac_interface_phy_nr::pdcch_ul_t;
+using pdcch_dl_list_t = srsran::bounded_vector<pdcch_dl_t, MAX_GRANTS>;
+using pdcch_ul_list_t = srsran::bounded_vector<pdcch_ul_t, MAX_GRANTS>;
 using pucch_t         = mac_interface_phy_nr::pucch_t;
 using pucch_list_t    = srsran::bounded_vector<pucch_t, MAX_GRANTS>;
 using pusch_t         = mac_interface_phy_nr::pusch_t;
@@ -159,48 +163,6 @@ public:
   std::vector<cc_params> cc_params;
 };
 
-///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-
-struct resource_guard {
-public:
-  resource_guard()                            = default;
-  resource_guard(const resource_guard& other) = delete;
-  resource_guard(resource_guard&& other)      = delete;
-  resource_guard& operator=(const resource_guard& other) = delete;
-  resource_guard& operator=(resource_guard&& other) = delete;
-  bool            busy() const { return flag; }
-
-  struct token {
-    token() = default;
-    token(resource_guard& parent) : flag(parent.busy() ? nullptr : &parent.flag)
-    {
-      if (flag != nullptr) {
-        *flag = true;
-      }
-    }
-    token(token&&) noexcept = default;
-    token& operator=(token&&) noexcept = default;
-    void   release() { flag.reset(); }
-    bool   owns_token() const { return flag != nullptr; }
-    bool   empty() const { return flag == nullptr; }
-
-  private:
-    struct release_deleter {
-      void operator()(bool* ptr)
-      {
-        if (ptr != nullptr) {
-          srsran_assert(*ptr == true, "resource token: detected inconsistency token state");
-          *ptr = false;
-        }
-      }
-    };
-    std::unique_ptr<bool, release_deleter> flag;
-  };
-
-private:
-  bool flag = false;
-};
-
 } // namespace sched_nr_impl
 
 } // namespace srsenb

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

@@ -41,6 +41,7 @@ public:
   uint32_t         ndi() const { return tb[0].ndi; }
   uint32_t         mcs() const { return tb[0].mcs; }
   const prb_grant& prbs() const { return prbs_; }
+  slot_point       harq_slot_tx() const { return slot_tx; }
   slot_point       harq_slot_ack() const { return slot_ack; }
 
   bool ack_info(uint32_t tb_idx, bool ack);
@@ -126,6 +127,11 @@ public:
   void dl_ack_info(uint32_t pid, uint32_t tb_idx, bool ack) { dl_harqs[pid].ack_info(tb_idx, ack); }
   void ul_crc_info(uint32_t pid, bool ack) { ul_harqs[pid].ack_info(0, ack); }
 
+  uint32_t            nof_dl_harqs() const { return dl_harqs.size(); }
+  uint32_t            nof_ul_harqs() const { return ul_harqs.size(); }
+  const dl_harq_proc& dl_harq(uint32_t pid) const { return dl_harqs[pid]; }
+  const ul_harq_proc& ul_harq(uint32_t pid) const { return ul_harqs[pid]; }
+
   dl_harq_proc* find_pending_dl_retx()
   {
     return find_dl([this](const dl_harq_proc& h) { return h.has_pending_retx(slot_rx); });

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

@@ -68,6 +68,7 @@ public:
   struct sched_cfg_t {
     bool        pdsch_enabled      = true;
     bool        pusch_enabled      = true;
+    bool        auto_refill_buffer = true;
     std::string logger_name        = "MAC";
   };
 

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

@@ -30,10 +30,6 @@ enum class pdcch_grant_type_t { sib, rar, dl_data, ul_data };
 class slot_ue;
 
 using bwp_cfg_t = sched_nr_interface::bwp_cfg_t;
-using pdcch_dl_t      = mac_interface_phy_nr::pdcch_dl_t;
-using pdcch_ul_t      = mac_interface_phy_nr::pdcch_ul_t;
-using pdcch_dl_list_t = srsran::bounded_vector<pdcch_dl_t, MAX_GRANTS>;
-using pdcch_ul_list_t = srsran::bounded_vector<pdcch_ul_t, MAX_GRANTS>;
 
 class coreset_region
 {

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

@@ -42,7 +42,7 @@ public:
   uint32_t   cc = SCHED_NR_MAX_CARRIERS;
 
   // UE parameters common to all sectors
-  bool pending_sr = false;
+  int dl_pending_bytes = 0, ul_pending_bytes = 0;
 
   // UE parameters that are sector specific
   const bwp_ue_cfg* cfg      = nullptr;
@@ -61,8 +61,7 @@ class ue_carrier
 {
 public:
   ue_carrier(uint16_t rnti, const ue_cfg_t& cfg, const sched_cell_params& cell_params_);
-  void    new_slot(slot_point pdcch_slot, const ue_cfg_t& uecfg_);
+  slot_ue try_reserve(slot_point pdcch_slot, const ue_cfg_t& uecfg_, uint32_t dl_harq_bytes, uint32_t ul_harq_bytes);
-  slot_ue try_reserve(slot_point pdcch_slot);
 
   const uint16_t rnti;
   const uint32_t cc;
@@ -83,25 +82,34 @@ class ue
 public:
   ue(uint16_t rnti, const ue_cfg_t& cfg, const sched_params& sched_cfg_);
 
+  void new_slot(slot_point pdcch_slot);
+
   slot_ue try_reserve(slot_point pdcch_slot, uint32_t cc);
 
   void            set_cfg(const ue_cfg_t& cfg);
   const ue_cfg_t& cfg() const { return ue_cfg; }
 
-  void ul_sr_info(slot_point slot_rx) { pending_sr = true; }
+  void rlc_buffer_state(uint32_t lcid, uint32_t newtx, uint32_t retx) { buffers.dl_buffer_state(lcid, newtx, retx); }
   void ul_bsr(uint32_t lcg, uint32_t bsr_val) { buffers.ul_bsr(lcg, bsr_val); }
-
+  void ul_sr_info(slot_point slot_rx) { last_sr_slot = slot_rx; }
-  bool     has_ca() const { return ue_cfg.carriers.size() > 1; }
+
+  bool has_ca() const
+  {
+    return ue_cfg.carriers.size() > 1 and std::count_if(ue_cfg.carriers.begin() + 1,
+                                                        ue_cfg.carriers.end(),
+                                                        [](const ue_cc_cfg_t& cc) { return cc.active; }) > 0;
+  }
   uint32_t pcell_cc() const { return ue_cfg.carriers[0].cc; }
 
+  ue_buffer_manager<true>                                        buffers;
   std::array<std::unique_ptr<ue_carrier>, SCHED_NR_MAX_CARRIERS> carriers;
 
 private:
   const uint16_t      rnti;
   const sched_params& sched_cfg;
 
-  bool                    pending_sr = false;
+  slot_point last_sr_slot;
-  ue_buffer_manager<true> buffers;
+  int        ul_pending_bytes = 0, dl_pending_bytes = 0;
 
   ue_cfg_t ue_cfg;
 };

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

@@ -39,7 +39,6 @@ public:
   explicit slot_cc_worker(serv_cell_manager& sched);
 
   void run(slot_point pdcch_slot, ue_map_t& ue_db_);
-  void finish();
   bool running() const { return slot_rx.valid(); }
 
   void enqueue_cc_event(srsran::move_callback<void()> ev);
@@ -102,6 +101,8 @@ public:
   }
 
 private:
+  void update_ue_db(slot_point slot_tx, bool update_ca_users);
+
   bool save_sched_result(slot_point pdcch_slot, uint32_t cc, dl_sched_res_t& dl_res, ul_sched_t& ul_res);
 
   const sched_params&                               cfg;

srsenb/src/stack/mac/common/ue_buffer_manager.cc

@@ -76,6 +76,18 @@ int ue_buffer_manager<isNR>::get_bsr(uint32_t lcg) const
   return is_lcg_active(lcg) ? lcg_bsr[lcg] : 0;
 }
 
+template <bool isNR>
+int ue_buffer_manager<isNR>::get_bsr() const
+{
+  uint32_t count = 0;
+  for (uint32_t lcg = 0; is_lcg_valid(lcg); ++lcg) {
+    if (is_lcg_active(lcg)) {
+      count += lcg_bsr[lcg];
+    }
+  }
+  return count;
+}
+
 template <bool isNR>
 void ue_buffer_manager<isNR>::ul_bsr(uint32_t lcg_id, uint32_t val)
 {

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

@@ -151,6 +151,17 @@ void sched_nr::ul_sr_info(slot_point slot_rx, uint16_t rnti)
   sched_workers->enqueue_event(rnti, [this, rnti, slot_rx]() { ue_db[rnti]->ul_sr_info(slot_rx); });
 }
 
+void sched_nr::ul_bsr(uint16_t rnti, uint32_t lcg_id, uint32_t bsr)
+{
+  sched_workers->enqueue_event(rnti, [this, rnti, lcg_id, bsr]() { ue_db[rnti]->ul_bsr(lcg_id, bsr); });
+}
+
+void sched_nr::dl_buffer_state(uint16_t rnti, uint32_t lcid, uint32_t newtx, uint32_t retx)
+{
+  sched_workers->enqueue_event(rnti,
+                               [this, rnti, lcid, newtx, retx]() { ue_db[rnti]->rlc_buffer_state(lcid, newtx, retx); });
+}
+
 #define VERIFY_INPUT(cond, msg, ...)                                                                                   \
   do {                                                                                                                 \
     if (not(cond)) {                                                                                                   \

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

@@ -29,23 +29,23 @@ ue_carrier::ue_carrier(uint16_t rnti_, const ue_cfg_t& uecfg_, const sched_cell_
   harq_ent(cell_params_.nof_prb())
 {}
 
-void ue_carrier::new_slot(slot_point pdcch_slot, const ue_cfg_t& uecfg_)
+slot_ue ue_carrier::try_reserve(slot_point      pdcch_slot,
+                                const ue_cfg_t& uecfg_,
+                                uint32_t        dl_pending_bytes,
+                                uint32_t        ul_pending_bytes)
 {
+  slot_point slot_rx = pdcch_slot - TX_ENB_DELAY;
+
+  // update CC/BWP config if there were changes
   if (bwp_cfg.ue_cfg() != &uecfg_) {
     bwp_cfg = bwp_ue_cfg(rnti, cell_params.bwps[0], uecfg_);
   }
-  harq_ent.new_slot(pdcch_slot - TX_ENB_DELAY);
-}
-
-slot_ue ue_carrier::try_reserve(slot_point pdcch_slot)
-{
-  slot_point slot_rx = pdcch_slot - TX_ENB_DELAY;
 
   // copy cc-specific parameters and find available HARQs
   slot_ue sfu(rnti, slot_rx, cc);
   sfu.cfg           = &bwp_cfg;
-  sfu.harq_ent      = &harq_ent;
   sfu.pdcch_slot    = pdcch_slot;
+  sfu.harq_ent      = &harq_ent;
   const uint32_t k0 = 0;
   sfu.pdsch_slot    = sfu.pdcch_slot + k0;
   uint32_t k1 =
@@ -57,45 +57,81 @@ slot_ue ue_carrier::try_reserve(slot_point pdcch_slot)
   sfu.dl_cqi     = dl_cqi;
   sfu.ul_cqi     = ul_cqi;
 
+  // set UE-common parameters
+  sfu.dl_pending_bytes = dl_pending_bytes;
+  sfu.ul_pending_bytes = ul_pending_bytes;
+
   const srsran_tdd_config_nr_t& tdd_cfg = cell_params.cell_cfg.tdd;
   if (srsran_tdd_nr_is_dl(&tdd_cfg, 0, sfu.pdsch_slot.slot_idx())) {
     // If DL enabled
     sfu.h_dl = harq_ent.find_pending_dl_retx();
-    if (sfu.h_dl == nullptr) {
+    if (sfu.h_dl == nullptr and sfu.dl_pending_bytes > 0) {
       sfu.h_dl = harq_ent.find_empty_dl_harq();
     }
   }
   if (srsran_tdd_nr_is_ul(&tdd_cfg, 0, sfu.pusch_slot.slot_idx())) {
     // If UL enabled
     sfu.h_ul = harq_ent.find_pending_ul_retx();
-    if (sfu.h_ul == nullptr) {
+    if (sfu.h_ul == nullptr and sfu.ul_pending_bytes > 0) {
       sfu.h_ul = harq_ent.find_empty_ul_harq();
     }
   }
 
-  if (sfu.h_dl == nullptr and sfu.h_ul == nullptr) {
-    // there needs to be at least one available HARQ for newtx/retx
-    sfu.release();
-    return sfu;
-  }
   return sfu;
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
 ue::ue(uint16_t rnti_, const ue_cfg_t& cfg, const sched_params& sched_cfg_) :
-  rnti(rnti_), sched_cfg(sched_cfg_), ue_cfg(cfg), buffers(srslog::fetch_basic_logger(sched_cfg_.sched_cfg.logger_name))
+  rnti(rnti_), sched_cfg(sched_cfg_), buffers(srslog::fetch_basic_logger(sched_cfg_.sched_cfg.logger_name))
 {
-  for (uint32_t cc = 0; cc < cfg.carriers.size(); ++cc) {
+  set_cfg(cfg);
-    if (cfg.carriers[cc].active) {
-      carriers[cc].reset(new ue_carrier(rnti, cfg, sched_cfg.cells[cc]));
-    }
-  }
 }
 
 void ue::set_cfg(const ue_cfg_t& cfg)
 {
   ue_cfg = cfg;
+  for (auto& ue_cc_cfg : cfg.carriers) {
+    if (ue_cc_cfg.active and carriers[ue_cc_cfg.cc] == nullptr) {
+      carriers[ue_cc_cfg.cc].reset(new ue_carrier(rnti, cfg, sched_cfg.cells[ue_cc_cfg.cc]));
+    }
+  }
+}
+
+void ue::new_slot(slot_point pdcch_slot)
+{
+  for (auto& ue_cc_cfg : ue_cfg.carriers) {
+    auto& cc = carriers[ue_cc_cfg.cc];
+    if (cc != nullptr) {
+      // Update CC HARQ state
+      cc->harq_ent.new_slot(pdcch_slot - TX_ENB_DELAY);
+    }
+  }
+
+  // Compute pending DL/UL bytes for {rnti, pdcch_slot}
+  if (sched_cfg.sched_cfg.auto_refill_buffer) {
+    dl_pending_bytes = 1000000;
+    ul_pending_bytes = 1000000;
+  } else {
+    dl_pending_bytes = buffers.get_dl_tx_total();
+    ul_pending_bytes = buffers.get_bsr();
+    for (auto& ue_cc_cfg : ue_cfg.carriers) {
+      auto& cc = carriers[ue_cc_cfg.cc];
+      if (cc != nullptr) {
+        // Discount UL HARQ pending bytes to BSR
+        for (uint32_t pid = 0; pid < cc->harq_ent.nof_dl_harqs(); ++pid) {
+          ul_pending_bytes -= cc->harq_ent.ul_harq(pid).tbs();
+          if (last_sr_slot.valid() and cc->harq_ent.ul_harq(pid).harq_slot_tx() > last_sr_slot) {
+            last_sr_slot.clear();
+          }
+        }
+      }
+    }
+    if (ul_pending_bytes == 0 and last_sr_slot.valid()) {
+      // If unanswered SR is pending
+      ul_pending_bytes = 512;
+    }
+  }
 }
 
 slot_ue ue::try_reserve(slot_point pdcch_slot, uint32_t cc)
@@ -103,14 +139,12 @@ slot_ue ue::try_reserve(slot_point pdcch_slot, uint32_t cc)
   if (carriers[cc] == nullptr) {
     return slot_ue();
   }
-  slot_ue sfu = carriers[cc]->try_reserve(pdcch_slot);
+
+  slot_ue sfu = carriers[cc]->try_reserve(pdcch_slot, cfg(), dl_pending_bytes, ul_pending_bytes);
   if (sfu.empty()) {
     return slot_ue();
   }
 
-  // set UE-common parameters
-  sfu.pending_sr = pending_sr;
-
   return sfu;
 }
 

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

@@ -75,8 +75,6 @@ void slot_cc_worker::run(slot_point pdcch_slot, ue_map_t& ue_db)
       continue;
     }
 
-    u.carriers[cfg.cc]->new_slot(pdcch_slot, u.cfg());
-
     slot_ues.insert(rnti, u.try_reserve(pdcch_slot, cfg.cc));
     if (slot_ues[rnti].empty()) {
       // Failed to generate slot UE because UE has no conditions for DL/UL tx
@@ -104,11 +102,6 @@ void slot_cc_worker::run(slot_point pdcch_slot, ue_map_t& ue_db)
   slot_rx = {};
 }
 
-void slot_cc_worker::finish()
-{
-  // synchronize results
-}
-
 void slot_cc_worker::alloc_dl_ues()
 {
   if (not cfg.sched_cfg.pdsch_enabled) {
@@ -151,6 +144,28 @@ void sched_worker_manager::enqueue_cc_event(uint32_t cc, srsran::move_callback<v
   cc_worker_list[cc]->worker.enqueue_cc_event(std::move(ev));
 }
 
+/**
+ * Update UEs state that is non-CC specific (e.g. SRs, buffer status, UE configuration)
+ * @param slot_tx
+ * @param update_ca_users to update only UEs with CA enabled or not
+ */
+void sched_worker_manager::update_ue_db(slot_point slot_tx, bool update_ca_users)
+{
+  // process non-cc specific feedback if pending (e.g. SRs, buffer updates, UE config)
+  for (ue_event_t& ev : slot_events) {
+    if (not ue_db.contains(ev.rnti) or ue_db[ev.rnti]->has_ca() == update_ca_users) {
+      ev.callback();
+    }
+  }
+
+  // prepare UEs internal state for new slot
+  for (auto& u : ue_db) {
+    if (u.second->has_ca() == update_ca_users) {
+      u.second->new_slot(slot_tx);
+    }
+  }
+}
+
 void sched_worker_manager::run_slot(slot_point slot_tx, uint32_t cc, dl_sched_res_t& dl_res, ul_sched_t& ul_res)
 {
   srsran::bounded_vector<std::condition_variable*, SRSRAN_MAX_CARRIERS> waiting_cvars;
@@ -165,18 +180,14 @@ void sched_worker_manager::run_slot(slot_point slot_tx, uint32_t cc, dl_sched_re
     if (not current_slot.valid()) {
       /* First Worker to start slot */
 
-      // process non-cc specific feedback if pending (e.g. SRs, buffer updates, UE config) for UEs with CA
+      // process non-cc specific feedback if pending for UEs with CA
       // NOTE: there is no parallelism in these operations
       slot_events.clear();
       {
         std::lock_guard<std::mutex> ev_lock(event_mutex);
         next_slot_events.swap(slot_events);
       }
-      for (ue_event_t& ev : slot_events) {
+      update_ue_db(slot_tx, true);
-        if (not ue_db.contains(ev.rnti) or ue_db[ev.rnti]->has_ca()) {
-          ev.callback();
-        }
-      }
 
       // mark the start of slot. awake remaining workers if locking on the mutex
       current_slot = slot_tx;
@@ -197,11 +208,7 @@ void sched_worker_manager::run_slot(slot_point slot_tx, uint32_t cc, dl_sched_re
   /* Parallel Region */
 
   // process non-cc specific feedback if pending (e.g. SRs, buffer updates, UE config) for UEs without CA
-  for (ue_event_t& ev : slot_events) {
+  update_ue_db(slot_tx, false);
-    if (ue_db.contains(ev.rnti) and not ue_db[ev.rnti]->has_ca() and ue_db[ev.rnti]->pcell_cc() == cc) {
-      ev.callback();
-    }
-  }
 
   // process pending feedback, generate {slot, cc} scheduling decision
   cc_worker_list[cc]->worker.run(slot_tx, ue_db);
@@ -218,7 +225,6 @@ void sched_worker_manager::run_slot(slot_point slot_tx, uint32_t cc, dl_sched_re
 
     // All the workers of the same slot have finished. Synchronize scheduling decisions with UEs state
     for (auto& c : cc_worker_list) {
-      c->worker.finish();
       if (c->waiting > 0) {
         waiting_cvars.push_back(&c->cvar);
       }

srsenb/test/mac/nr/sched_nr_rar_test.cc

@@ -29,7 +29,11 @@ void test_single_prach()
   std::default_random_engine   rand_gen(seed);
   std::default_random_engine   rgen(rand_gen());
 
+  // Set scheduler configuration
   sched_nr_interface::sched_cfg_t sched_cfg{};
+  sched_cfg.auto_refill_buffer = std::uniform_int_distribution<uint32_t>{0, 1}(rgen) > 0;
+
+  // Set cells configuration
   std::vector<sched_nr_interface::cell_cfg_t> cells_cfg = get_default_cells_cfg(1);
   sched_params                                schedparams{sched_cfg};
   schedparams.cells.emplace_back(0, cells_cfg[0], sched_cfg);
@@ -52,10 +56,14 @@ void test_single_prach()
   const bwp_slot_grid* result   = nullptr;
   auto                 run_slot = [&alloc, &rasched, &pdcch_slot, &slot_ues, &u]() -> const bwp_slot_grid* {
     mac_logger.set_context(pdcch_slot.to_uint());
-    u.carriers[0]->new_slot(pdcch_slot, u.cfg());
+    u.new_slot(pdcch_slot);
     slot_ues.clear();
-    slot_ues.insert(rnti, u.try_reserve(pdcch_slot, 0));
+    slot_ue sfu = u.try_reserve(pdcch_slot, 0);
+    if (not sfu.empty()) {
+      slot_ues.insert(rnti, std::move(sfu));
+    }
     alloc.new_slot(pdcch_slot, slot_ues);
+
     rasched.run_slot(alloc);
 
     log_sched_bwp_result(mac_logger, alloc.get_pdcch_tti(), alloc.res_grid(), slot_ues);