rlc: fix issue when t-StatusProhibit is configured to 0

lib/src/rlc/rlc_am_nr.cc

@@ -33,7 +33,8 @@ const static uint32_t max_tx_queue_size = 256;
  ***************************************************************************/
 rlc_am_nr_tx::rlc_am_nr_tx(rlc_am* parent_) :
   parent(parent_), rlc_am_base_tx(parent_->logger), poll_retransmit_timer(parent->timers->get_unique_timer())
-{}
+{
+}
 
 bool rlc_am_nr_tx::configure(const rlc_config_t& cfg_)
 {
@@ -1364,7 +1365,8 @@ rlc_am_nr_rx::rlc_am_nr_rx(rlc_am* parent_) :
   status_prohibit_timer(parent->timers->get_unique_timer()),
   reassembly_timer(parent->timers->get_unique_timer()),
   rlc_am_base_rx(parent_, parent_->logger)
-{}
+{
+}
 
 bool rlc_am_nr_rx::configure(const rlc_config_t& cfg_)
 {
@@ -1814,7 +1816,7 @@ uint32_t rlc_am_nr_rx::get_status_pdu(rlc_am_nr_status_pdu_t* status, uint32_t m
 
   if (max_len != UINT32_MAX) {
     // UINT32_MAX is used just to query the status PDU length
-    if (status_prohibit_timer.is_valid()) {
+    if (status_prohibit_timer.is_valid() && cfg.t_status_prohibit != 0) {
       status_prohibit_timer.run();
     }
     do_status = false;
@@ -1832,7 +1834,11 @@ uint32_t rlc_am_nr_rx::get_status_pdu_length()
 
 bool rlc_am_nr_rx::get_do_status()
 {
-  return do_status.load(std::memory_order_relaxed) && not status_prohibit_timer.is_running();
+  if (cfg.t_status_prohibit != 0) {
+    return do_status.load(std::memory_order_relaxed) && not status_prohibit_timer.is_running();
+  } else {
+    return do_status.load(std::memory_order_relaxed);
+  }
 }
 
 void rlc_am_nr_rx::timer_expired(uint32_t timeout_id)

lib/test/rlc/rlc_am_nr_test.cc

@@ -3287,6 +3287,76 @@ int lost_status_and_advanced_rx_window(rlc_am_nr_sn_size_t sn_size)
   return SRSRAN_SUCCESS;
 }
 
+// If we lose the status report
+int do_status_0ms_status_prohibit(rlc_am_nr_sn_size_t sn_size)
+{
+  rlc_am_tester tester(true, nullptr);
+  timer_handler timers(8);
+  byte_buffer_t pdu_bufs[NBUFS];
+
+  auto&               test_logger = srslog::fetch_basic_logger("TESTER  ");
+  test_delimit_logger delimiter("Do status 0ms status prohibit ({} bit SN)", to_number(sn_size));
+  rlc_am              rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers);
+  rlc_am              rlc2(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_2"), 1, &tester, &tester, &timers);
+
+  rlc_am_nr_tx* tx1 = dynamic_cast<rlc_am_nr_tx*>(rlc1.get_tx());
+  rlc_am_nr_rx* rx1 = dynamic_cast<rlc_am_nr_rx*>(rlc1.get_rx());
+  rlc_am_nr_tx* tx2 = dynamic_cast<rlc_am_nr_tx*>(rlc2.get_tx());
+  rlc_am_nr_rx* rx2 = dynamic_cast<rlc_am_nr_rx*>(rlc2.get_rx());
+
+  auto cfg                    = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
+  cfg.am_nr.t_status_prohibit = 0;
+  if (not rlc1.configure(cfg)) {
+    return -1;
+  }
+  if (not rlc2.configure(cfg)) {
+    return -1;
+  }
+  uint32_t mod_nr = cardinality(cfg.am_nr.tx_sn_field_length);
+
+  // Tx 5 PDUs
+  constexpr uint32_t payload_size = 3; // Give the SDU the size of 3 bytes
+  uint32_t           header_size  = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3;
+  for (uint32_t sn = 0; sn < 5; ++sn) {
+    // Write SDU
+    unique_byte_buffer_t sdu_buf = srsran::make_byte_buffer();
+    sdu_buf->msg[0]              = sn;           // Write the index into the buffer
+    sdu_buf->N_bytes             = payload_size; // Give each buffer a size of 3 bytes
+    sdu_buf->md.pdcp_sn          = sn;           // PDCP SN for notifications
+    rlc1.write_sdu(std::move(sdu_buf));
+
+    // Read PDU
+    unique_byte_buffer_t pdu_buf = srsran::make_byte_buffer();
+    pdu_buf->N_bytes             = rlc1.read_pdu(pdu_buf->msg, 100);
+
+    // Write PDU into RLC 2
+    // We receive all PDUs
+    rlc2.write_pdu(pdu_buf->msg, pdu_buf->N_bytes);
+  }
+
+  // Read status PDU
+  {
+    TESTASSERT_EQ(0, rlc1.get_buffer_state());
+    unique_byte_buffer_t status_buf = srsran::make_byte_buffer();
+    status_buf->N_bytes             = rlc2.read_pdu(status_buf->msg, 1000);
+  }
+
+  // Let timers run for t-PollRetransmit expire
+  {
+    for (int cnt = 0; cnt < 45; cnt++) {
+      timers.step_all();
+    }
+    TESTASSERT_EQ(header_size + payload_size, rlc1.get_buffer_state());
+    TESTASSERT_EQ(0, rlc2.get_buffer_state());
+    unique_byte_buffer_t poll_buf = srsran::make_byte_buffer();
+    poll_buf->N_bytes             = rlc1.read_pdu(poll_buf->msg, 1000);
+    rlc2.write_pdu(poll_buf->msg, poll_buf->N_bytes);
+    TESTASSERT_NEQ(0, rlc2.get_buffer_state());
+  }
+
+  return SRSRAN_SUCCESS;
+}
+
 int full_rx_window_t_reassembly_expiry(rlc_am_nr_sn_size_t sn_size)
 {
   rlc_am_tester tester(false, nullptr);