Added check for consequetive KOs in MAC. Change set_activity_user to pass activity and max KOs to RRC and trigger RLF timeout.

lib/include/srsran/common/common.h

@@ -18,9 +18,10 @@
 *******************************************************************************/
 
 #include <chrono>
+#include <cstring>
 #include <memory>
 #include <stdint.h>
-#include <string.h>
+#include <string>
 #include <sys/time.h>
 
 /*******************************************************************************

lib/include/srsran/interfaces/enb_mac_interfaces.h

@@ -23,6 +23,7 @@ struct mac_args_t {
   sched_interface::sched_args_t sched;
   int                           nr_tb_size = -1;
   uint32_t                      max_nof_ues;
+  uint32_t                      max_nof_kos;
 };
 
 /* Interface PHY -> MAC */

lib/include/srsran/interfaces/enb_rrc_interfaces.h

@@ -73,7 +73,7 @@ public:
   /* Radio Link failure */
   virtual int  add_user(uint16_t rnti, const sched_interface::ue_cfg_t& init_ue_cfg) = 0;
   virtual void upd_user(uint16_t new_rnti, uint16_t old_rnti)                        = 0;
-  virtual void set_activity_user(uint16_t rnti)                                      = 0;
+  virtual void set_activity_user(uint16_t rnti, bool ack_info)                       = 0;
   virtual bool is_paging_opportunity(uint32_t tti, uint32_t* payload_len)            = 0;
 
   ///< Provide packed SIB to MAC (buffer is managed by RRC)

srsenb/enb.conf.example

@@ -324,6 +324,7 @@ enable = false
 #pregenerate_signals  = false
 #tx_amplitude         = 0.6
 #rrc_inactivity_timer = 30000
+#max_nof_kos          = 256
 #max_prach_offset_us  = 30
 #eea_pref_list = EEA0, EEA2, EEA1
 #eia_pref_list = EIA2, EIA1, EIA0

srsenb/hdr/stack/mac/ue.h

@@ -139,7 +139,7 @@ public:
   generate_mch_pdu(uint32_t harq_pid, sched_interface::dl_pdu_mch_t sched, uint32_t nof_pdu_elems, uint32_t grant_size);
 
   srsran_softbuffer_tx_t*
-                          get_tx_softbuffer(const uint32_t ue_cc_idx, const uint32_t harq_process, const uint32_t tb_idx);
+  get_tx_softbuffer(const uint32_t ue_cc_idx, const uint32_t harq_process, const uint32_t tb_idx);
   srsran_softbuffer_rx_t* get_rx_softbuffer(const uint32_t ue_cc_idx, const uint32_t tti);
 
   bool     process_pdus();
@@ -160,6 +160,8 @@ public:
 
   int read_pdu(uint32_t lcid, uint8_t* payload, uint32_t requested_bytes) final;
 
+  uint32_t ko_counter = 0;
+
 private:
   void allocate_sdu(srsran::sch_pdu* pdu, uint32_t lcid, uint32_t sdu_len);
   bool process_ce(srsran::sch_subh* subh);

srsenb/hdr/stack/rrc/rrc.h

@@ -67,7 +67,7 @@ public:
   // rrc_interface_mac
   int      add_user(uint16_t rnti, const sched_interface::ue_cfg_t& init_ue_cfg) override;
   void     upd_user(uint16_t new_rnti, uint16_t old_rnti) override;
-  void     set_activity_user(uint16_t rnti) override;
+  void     set_activity_user(uint16_t rnti, bool ack_info) override;
   bool     is_paging_opportunity(uint32_t tti, uint32_t* payload_len) override;
   uint8_t* read_pdu_bcch_dlsch(const uint8_t cc_idx, const uint32_t sib_index) override;
 

srsenb/src/main.cc

@@ -214,6 +214,7 @@ void parse_args(all_args_t* args, int argc, char* argv[])
     ("expert.eea_pref_list", bpo::value<string>(&args->general.eea_pref_list)->default_value("EEA0, EEA2, EEA1"), "Ordered preference list for the selection of encryption algorithm (EEA) (default: EEA0, EEA2, EEA1).")
     ("expert.eia_pref_list", bpo::value<string>(&args->general.eia_pref_list)->default_value("EIA2, EIA1, EIA0"), "Ordered preference list for the selection of integrity algorithm (EIA) (default: EIA2, EIA1, EIA0).")
     ("expert.max_nof_ues", bpo::value<uint32_t>(&args->stack.mac.max_nof_ues)->default_value(64), "Maximum number of connected UEs")
+    ("expert.max_nof_kos", bpo::value<uint32_t>(&args->stack.mac.max_nof_kos)->default_value(254), "Maximum number of consecutive KOs before triggering the UE's release")
 
     // eMBMS section
     ("embms.enable", bpo::value<bool>(&args->stack.embms.enable)->default_value(false), "Enables MBMS in the eNB")

srsenb/src/stack/mac/mac.cc

@@ -292,10 +292,17 @@ int mac::ack_info(uint32_t tti_rx, uint16_t rnti, uint32_t enb_cc_idx, uint32_t
   ue_db[rnti]->metrics_tx(ack, nof_bytes);
 
   if (ack) {
+    ue_db[rnti]->ko_counter = 0;
     if (nof_bytes > 64) { // do not count RLC status messages only
-      rrc_h->set_activity_user(rnti);
+      rrc_h->set_activity_user(rnti, true);
       logger.info("DL activity rnti=0x%x, n_bytes=%d", rnti, nof_bytes);
     }
+  } else {
+    ue_db[rnti]->ko_counter++;
+    if (ue_db[rnti]->ko_counter > args.max_nof_kos) {
+      rrc_h->set_activity_user(rnti, false);
+      logger.info("DL max KOs reached rnti=0x%x, n_bytes=%d", rnti, nof_bytes);
+    }
   }
   return SRSRAN_SUCCESS;
 }
@@ -830,9 +837,9 @@ int mac::get_mch_sched(uint32_t tti, bool is_mcch, dl_sched_list_t& dl_sched_res
       int requested_bytes = (mcs_data.tbs / 8 > (int)mch.mtch_sched[mtch_index].lcid_buffer_size)
                                 ? (mch.mtch_sched[mtch_index].lcid_buffer_size)
                                 : ((mcs_data.tbs / 8) - 2);
-      int bytes_received = ue_db[SRSRAN_MRNTI]->read_pdu(current_lcid, mtch_payload_buffer, requested_bytes);
+      int bytes_received  = ue_db[SRSRAN_MRNTI]->read_pdu(current_lcid, mtch_payload_buffer, requested_bytes);
-      mch.pdu[0].lcid    = current_lcid;
+      mch.pdu[0].lcid     = current_lcid;
-      mch.pdu[0].nbytes  = bytes_received;
+      mch.pdu[0].nbytes   = bytes_received;
       mch.mtch_sched[0].mtch_payload  = mtch_payload_buffer;
       dl_sched_res->pdsch[0].dci.rnti = SRSRAN_MRNTI;
       if (bytes_received) {

srsenb/src/stack/mac/ue.cc

@@ -373,7 +373,7 @@ void ue::process_pdu(uint8_t* pdu, uint32_t nof_bytes, srsran::pdu_queue::channe
 
       // Indicate RRC about successful activity if valid RLC message is received
       if (mac_msg_ul.get()->get_payload_size() > 64) { // do not count RLC status messages only
-        rrc->set_activity_user(rnti);
+        rrc->set_activity_user(rnti, true);
         logger.debug("UL activity rnti=0x%x, n_bytes=%d", rnti, nof_bytes);
       }
 
@@ -423,10 +423,8 @@ void ue::deallocate_pdu(uint32_t tti, uint32_t ue_cc_idx)
 {
   std::unique_lock<std::mutex> lock(rx_buffers_mutex);
   if (not cc_buffers[ue_cc_idx].get_rx_used_buffers().try_deallocate_pdu(tti_point(tti))) {
-    logger.warning("UE buffers: Null RX PDU pointer in deallocate_pdu for rnti=0x%x tti=%d cc_idx=%d",
+    logger.warning(
-                   rnti,
+        "UE buffers: Null RX PDU pointer in deallocate_pdu for rnti=0x%x tti=%d cc_idx=%d", rnti, tti, ue_cc_idx);
-                   tti,
-                   ue_cc_idx);
   }
 }
 
@@ -434,8 +432,7 @@ void ue::push_pdu(uint32_t tti, uint32_t ue_cc_idx, uint32_t len)
 {
   std::unique_lock<std::mutex> lock(rx_buffers_mutex);
   if (not cc_buffers[ue_cc_idx].get_rx_used_buffers().push_pdu(tti_point(tti), len)) {
-    logger.warning(
+    logger.warning("UE buffers: Failed to push RX PDU for rnti=0x%x tti=%d cc_idx=%d", rnti, tti, ue_cc_idx);
-        "UE buffers: Failed to push RX PDU for rnti=0x%x tti=%d cc_idx=%d", rnti, tti, ue_cc_idx);
   }
 }
 

srsenb/src/stack/rrc/rrc.cc

@@ -131,9 +131,15 @@ uint8_t* rrc::read_pdu_bcch_dlsch(const uint8_t cc_idx, const uint32_t sib_index
   return nullptr;
 }
 
-void rrc::set_activity_user(uint16_t rnti)
+void rrc::set_activity_user(uint16_t rnti, bool ack_info)
 {
-  rrc_pdu p = {rnti, LCID_ACT_USER, nullptr};
+  rrc_pdu p;
+  if (ack_info) {
+    p = {rnti, LCID_ACT_USER, nullptr};
+  } else {
+    p = {rnti, LCID_RTX_USER, nullptr};
+  }
+
   if (not rx_pdu_queue.try_push(std::move(p))) {
     logger.error("Failed to push UE activity command to RRC queue");
   }

srsenb/src/stack/rrc/rrc_ue.cc

@@ -103,7 +103,6 @@ void rrc::ue::set_activity()
 {
   // re-start activity timer with current timeout value
   activity_timer.run();
-
   if (parent) {
     parent->logger.debug("Activity registered for rnti=0x%x (timeout_value=%dms)", rnti, activity_timer.duration());
   }

srsenb/test/mac/sched_test_common.h

@@ -34,7 +34,7 @@ struct rrc_dummy : public rrc_interface_mac {
 public:
   int      add_user(uint16_t rnti, const sched_interface::ue_cfg_t& init_ue_cfg) { return SRSRAN_SUCCESS; }
   void     upd_user(uint16_t new_rnti, uint16_t old_rnti) {}
-  void     set_activity_user(uint16_t rnti) {}
+  void     set_activity_user(uint16_t rnti, bool ack_info) {}
   bool     is_paging_opportunity(uint32_t tti, uint32_t* payload_len) { return false; }
   uint8_t* read_pdu_bcch_dlsch(const uint8_t enb_cc_idx, const uint32_t sib_index) { return nullptr; }
 };