/** * * \section COPYRIGHT * * Copyright 2013-2021 Software Radio Systems Limited * * By using this file, you agree to the terms and conditions set * forth in the LICENSE file which can be found at the top level of * the distribution. * */ #include "rlc_test_common.h" #include "srsran/common/buffer_pool.h" #include "srsran/common/rlc_pcap.h" #include "srsran/common/test_common.h" #include "srsran/common/threads.h" #include "srsran/interfaces/ue_pdcp_interfaces.h" #include "srsran/interfaces/ue_rrc_interfaces.h" #include "srsran/rlc/rlc_am_nr.h" #define NBUFS 5 #define HAVE_PCAP 0 #define SDU_SIZE 500 using namespace srsue; using namespace srsran; int basic_test_tx(rlc_am* rlc, byte_buffer_t pdu_bufs[NBUFS], rlc_am_nr_sn_size_t sn_size) { // Push 5 SDUs into RLC1 unique_byte_buffer_t sdu_bufs[NBUFS]; constexpr uint32_t payload_size = 1; // Give each buffer a size of 1 byte for (int i = 0; i < NBUFS; i++) { sdu_bufs[i] = srsran::make_byte_buffer(); sdu_bufs[i]->msg[0] = i; // Write the index into the buffer sdu_bufs[i]->N_bytes = payload_size; // Give each buffer a size of 1 byte sdu_bufs[i]->md.pdcp_sn = i; // PDCP SN for notifications rlc->write_sdu(std::move(sdu_bufs[i])); } uint32_t header_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3; uint32_t data_pdu_size = header_size + payload_size; uint32_t expect_buffer_state = NBUFS * data_pdu_size; TESTASSERT_EQ(expect_buffer_state, rlc->get_buffer_state()); // Read 5 PDUs from RLC1 (1 byte each) for (int i = 0; i < NBUFS; i++) { uint32_t len = rlc->read_pdu(pdu_bufs[i].msg, data_pdu_size); pdu_bufs[i].N_bytes = len; TESTASSERT_EQ(data_pdu_size, len); } TESTASSERT_EQ(0, rlc->get_buffer_state()); return SRSRAN_SUCCESS; } /* * Test the limits of the TX/RX window checkers * */ int window_checker_test(rlc_am_nr_sn_size_t sn_size) { rlc_am_tester tester; timer_handler timers(8); auto& test_logger = srslog::fetch_basic_logger("TESTER "); test_delimit_logger delimiter("window checkers"); rlc_am rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers); rlc_am_nr_tx* tx = dynamic_cast(rlc1.get_tx()); rlc_am_nr_rx* rx = dynamic_cast(rlc1.get_rx()); if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) { return SRSRAN_ERROR; } { // RLC1 RX_NEXT == 0 and RLC2 TX_NEXT_ACK == 0 uint32_t sn_inside_below = 0; uint32_t sn_inside_above = cardinality(sn_size) / 2 - 1; uint32_t sn_outside_below = cardinality(sn_size) - 1; uint32_t sn_outside_above = cardinality(sn_size) / 2; TESTASSERT_EQ(true, rx->inside_rx_window(sn_inside_below)); TESTASSERT_EQ(true, rx->inside_rx_window(sn_inside_above)); TESTASSERT_EQ(false, rx->inside_rx_window(sn_outside_below)); TESTASSERT_EQ(false, rx->inside_rx_window(sn_outside_above)); TESTASSERT_EQ(true, tx->inside_tx_window(sn_inside_below)); TESTASSERT_EQ(true, tx->inside_tx_window(sn_inside_above)); TESTASSERT_EQ(false, tx->inside_tx_window(sn_outside_below)); TESTASSERT_EQ(false, tx->inside_tx_window(sn_outside_above)); } rlc_am_nr_rx_state_t rx_st = {}; rx_st.rx_next = cardinality(sn_size) - 1; ; rlc_am_nr_tx_state_t tx_st = {}; tx_st.tx_next_ack = cardinality(sn_size) - 1; ; rx->set_rx_state(rx_st); tx->set_tx_state(tx_st); { // RX_NEXT == 4095 TX_NEXT_ACK == 4095 uint32_t sn_inside_below = 0; uint32_t sn_inside_above = cardinality(sn_size) / 2 - 2; uint32_t sn_outside_below = cardinality(sn_size) - 2; uint32_t sn_outside_above = cardinality(sn_size) / 2; TESTASSERT_EQ(true, rx->inside_rx_window(sn_inside_below)); TESTASSERT_EQ(true, rx->inside_rx_window(sn_inside_above)); TESTASSERT_EQ(false, rx->inside_rx_window(sn_outside_below)); TESTASSERT_EQ(false, rx->inside_rx_window(sn_outside_above)); TESTASSERT_EQ(true, tx->inside_tx_window(sn_inside_below)); TESTASSERT_EQ(true, tx->inside_tx_window(sn_inside_above)); TESTASSERT_EQ(false, tx->inside_tx_window(sn_outside_below)); TESTASSERT_EQ(false, tx->inside_tx_window(sn_outside_above)); } return SRSRAN_SUCCESS; } /* * Test is retx_segmentation required * */ int retx_segmentation_required_checker_test(rlc_am_nr_sn_size_t sn_size) { rlc_am_tester tester; timer_handler timers(8); auto& test_logger = srslog::fetch_basic_logger("TESTER "); test_delimit_logger delimiter("retx segmentation required checkers"); rlc_am rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers); rlc_am_nr_tx* tx = dynamic_cast(rlc1.get_tx()); rlc_am_nr_rx* rx = dynamic_cast(rlc1.get_rx()); if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) { return SRSRAN_ERROR; } unique_byte_buffer_t sdu_bufs[NBUFS]; unique_byte_buffer_t pdu_bufs[NBUFS]; for (int i = 0; i < NBUFS; i++) { sdu_bufs[i] = srsran::make_byte_buffer(); pdu_bufs[i] = srsran::make_byte_buffer(); sdu_bufs[i]->msg[0] = i; // Write the index into the buffer sdu_bufs[i]->N_bytes = 5; // Give each buffer a size of 1 byte sdu_bufs[i]->md.pdcp_sn = i; // PDCP SN for notifications rlc1.write_sdu(std::move(sdu_bufs[i])); rlc1.read_pdu(pdu_bufs[i]->msg, 8); } // Test full SDU retx { uint32_t nof_bytes = 8; rlc_amd_retx_nr_t retx = {}; retx.sn = 0; retx.is_segment = false; tx->is_retx_segmentation_required(retx, nof_bytes); TESTASSERT_EQ(false, tx->is_retx_segmentation_required(retx, nof_bytes)); } // Test SDU retx segmentation required { uint32_t nof_bytes = 4; rlc_amd_retx_nr_t retx; retx.sn = 0; retx.is_segment = false; tx->is_retx_segmentation_required(retx, nof_bytes); TESTASSERT_EQ(true, tx->is_retx_segmentation_required(retx, nof_bytes)); } // Test full SDU segment retx { uint32_t nof_bytes = 40; rlc_amd_retx_nr_t retx = {}; retx.sn = 0; retx.is_segment = true; retx.so_start = 4; retx.segment_length = 2; tx->is_retx_segmentation_required(retx, nof_bytes); TESTASSERT_EQ(false, tx->is_retx_segmentation_required(retx, nof_bytes)); } // Test SDU segment retx segmentation required { uint32_t nof_bytes = 4; rlc_amd_retx_nr_t retx = {}; retx.sn = 0; retx.is_segment = true; retx.so_start = 4; retx.segment_length = 2; tx->is_retx_segmentation_required(retx, nof_bytes); TESTASSERT_EQ(true, tx->is_retx_segmentation_required(retx, nof_bytes)); } return SRSRAN_SUCCESS; } /* * Test the transmission and acknowledgement of 5 SDUs. * * Each SDU is transmitted as a single PDU. * There are no lost PDUs, and the byte size is small, so the Poll_PDU configuration * will trigger the status report. * Poll PDU is configured to 4, so the 5th PDU should set the polling bit. */ int basic_test(rlc_am_nr_sn_size_t sn_size) { rlc_am_tester tester; timer_handler timers(8); byte_buffer_t pdu_bufs[NBUFS]; auto& test_logger = srslog::fetch_basic_logger("TESTER "); test_delimit_logger delimiter("basic tx/rx"); 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(rlc1.get_tx()); rlc_am_nr_rx* rx1 = dynamic_cast(rlc1.get_rx()); rlc_am_nr_tx* tx2 = dynamic_cast(rlc2.get_tx()); rlc_am_nr_rx* rx2 = dynamic_cast(rlc2.get_rx()); // before configuring entity TESTASSERT_EQ(0, rlc1.get_buffer_state()); if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) { return -1; } if (not rlc2.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) { return -1; } basic_test_tx(&rlc1, pdu_bufs, sn_size); // Write 5 PDUs into RLC2 for (int i = 0; i < NBUFS; i++) { rlc2.write_pdu(pdu_bufs[i].msg, pdu_bufs[i].N_bytes); } TESTASSERT_EQ(3, rlc2.get_buffer_state()); // Read status PDU from RLC2 byte_buffer_t status_buf; int len = rlc2.read_pdu(status_buf.msg, 3); status_buf.N_bytes = len; TESTASSERT_EQ(0, rlc2.get_buffer_state()); // Assert status is correct rlc_am_nr_status_pdu_t status_check = {}; rlc_am_nr_read_status_pdu(&status_buf, sn_size, &status_check); TESTASSERT_EQ(5, status_check.ack_sn); // 5 is the last SN that was not received. // Write status PDU to RLC1 rlc1.write_pdu(status_buf.msg, status_buf.N_bytes); // Check TX_NEXT_ACK rlc_am_nr_tx_state_t st = tx1->get_tx_state(); TESTASSERT_EQ(5, st.tx_next_ack); TESTASSERT_EQ(0, tx1->get_tx_window_size()); // Check PDCP notifications TESTASSERT_EQ(5, tester.notified_counts.size()); for (uint16_t i = 0; i < tester.sdus.size(); i++) { TESTASSERT_EQ(1, tester.sdus[i]->N_bytes); TESTASSERT_EQ(i, *(tester.sdus[i]->msg)); TESTASSERT_EQ(1, tester.notified_counts[i]); } // Check statistics rlc_bearer_metrics_t metrics1 = rlc1.get_metrics(); rlc_bearer_metrics_t metrics2 = rlc2.get_metrics(); constexpr uint32_t payload_size = 1; uint32_t header_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3; uint32_t data_pdu_size = header_size + payload_size; constexpr uint32_t status_pdu_size = 3; uint32_t total_tx_pdu_bytes = NBUFS * data_pdu_size; // NBUFS * PDU size uint32_t total_rx_pdu_bytes = status_pdu_size; // One status PDU // RLC1 PDU metrics TESTASSERT_EQ(5, metrics1.num_tx_sdus); TESTASSERT_EQ(0, metrics1.num_rx_sdus); TESTASSERT_EQ(5, metrics1.num_tx_sdu_bytes); TESTASSERT_EQ(0, metrics1.num_rx_sdu_bytes); TESTASSERT_EQ(0, metrics1.num_lost_sdus); // RLC1 SDU metrics TESTASSERT_EQ(5, metrics1.num_tx_pdus); TESTASSERT_EQ(1, metrics1.num_rx_pdus); // One status PDU TESTASSERT_EQ(total_tx_pdu_bytes, metrics1.num_tx_pdu_bytes); // NBUFS * PDU size TESTASSERT_EQ(total_rx_pdu_bytes, metrics1.num_rx_pdu_bytes); // One status PDU TESTASSERT_EQ(0, metrics1.num_lost_sdus); // No lost SDUs // RLC2 PDU metrics TESTASSERT_EQ(0, metrics2.num_tx_sdus); TESTASSERT_EQ(5, metrics2.num_rx_sdus); TESTASSERT_EQ(0, metrics2.num_tx_sdu_bytes); TESTASSERT_EQ(5, metrics2.num_rx_sdu_bytes); TESTASSERT_EQ(0, metrics2.num_lost_sdus); // RLC2 SDU metrics TESTASSERT_EQ(1, metrics2.num_tx_pdus); // One status PDU TESTASSERT_EQ(5, metrics2.num_rx_pdus); // 5 SDUs TESTASSERT_EQ(total_rx_pdu_bytes, metrics2.num_tx_pdu_bytes); // One status PDU TESTASSERT_EQ(total_tx_pdu_bytes, metrics2.num_rx_pdu_bytes); // NBUFS * PDU size TESTASSERT_EQ(0, metrics2.num_lost_sdus); // No lost SDUs return SRSRAN_SUCCESS; } /* * Test the loss of a single PDU. * NACK should be visible in the status report. * Retx after NACK should be present too. */ int lost_pdu_test(rlc_am_nr_sn_size_t sn_size) { rlc_am_tester tester; timer_handler timers(8); byte_buffer_t pdu_bufs[NBUFS]; auto& test_logger = srslog::fetch_basic_logger("TESTER "); 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); test_delimit_logger delimiter("lost PDU"); constexpr uint32_t payload_size = 1; uint32_t header_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3; uint32_t data_pdu_size = header_size + payload_size; uint32_t expect_buffer_state = NBUFS * data_pdu_size; // before configuring entity TESTASSERT(0 == rlc1.get_buffer_state()); if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) { return -1; } if (not rlc2.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) { return -1; } basic_test_tx(&rlc1, pdu_bufs, sn_size); // Write 5 PDUs into RLC2 for (int i = 0; i < NBUFS; i++) { if (i != 3) { rlc2.write_pdu(pdu_bufs[i].msg, pdu_bufs[i].N_bytes); // Don't write RLC_SN=3. } } // Only after t-reassembly has expired, will the status report include NACKs. TESTASSERT_EQ(3, rlc2.get_buffer_state()); { // Read status PDU from RLC2 byte_buffer_t status_buf; int len = rlc2.read_pdu(status_buf.msg, 5); status_buf.N_bytes = len; TESTASSERT(0 == rlc2.get_buffer_state()); // Assert status is correct rlc_am_nr_status_pdu_t status_check = {}; rlc_am_nr_read_status_pdu(&status_buf, sn_size, &status_check); TESTASSERT_EQ(3, status_check.ack_sn); // 3 is the next expected SN (i.e. the lost packet.) // Write status PDU to RLC1 rlc1.write_pdu(status_buf.msg, status_buf.N_bytes); } // Step timers until reassambly timeout expires for (int cnt = 0; cnt < 35; cnt++) { timers.step_all(); } // t-reassembly has expired. There should be a NACK in the status report. constexpr uint32_t status_pdu_ack_size = 3; uint32_t status_pdu_nack_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3; TESTASSERT_EQ(status_pdu_ack_size + status_pdu_nack_size, rlc2.get_buffer_state()); { // Read status PDU from RLC2 byte_buffer_t status_buf; uint32_t len = rlc2.read_pdu(status_buf.msg, status_pdu_ack_size + status_pdu_nack_size); status_buf.N_bytes = len; TESTASSERT_EQ(0, rlc2.get_buffer_state()); // Assert status is correct rlc_am_nr_status_pdu_t status_check = {}; rlc_am_nr_read_status_pdu(&status_buf, sn_size, &status_check); TESTASSERT_EQ(5, status_check.ack_sn); // 5 is the next expected SN. TESTASSERT_EQ(1, status_check.N_nack); // We lost one PDU. TESTASSERT_EQ(3, status_check.nacks[0].nack_sn); // Lost PDU SN=3. // Write status PDU to RLC1 rlc1.write_pdu(status_buf.msg, status_buf.N_bytes); // Check there is an Retx of SN=3 TESTASSERT_EQ(data_pdu_size, rlc1.get_buffer_state()); } { // Check correct re-transmission byte_buffer_t retx_buf; uint32_t len = rlc1.read_pdu(retx_buf.msg, data_pdu_size); retx_buf.N_bytes = len; TESTASSERT_EQ(data_pdu_size, len); rlc2.write_pdu(retx_buf.msg, retx_buf.N_bytes); TESTASSERT_EQ(0, rlc2.get_buffer_state()); } // Check statistics rlc_bearer_metrics_t metrics1 = rlc1.get_metrics(); rlc_bearer_metrics_t metrics2 = rlc2.get_metrics(); uint32_t total_tx_pdu_bytes1 = (NBUFS + 1) * data_pdu_size; // (NBUFS + 1 RETX) * PDU size uint32_t total_rx_pdu_bytes1 = 2 * status_pdu_ack_size + status_pdu_nack_size; // Two status PDU (one with a NACK) uint32_t total_tx_pdu_bytes2 = total_rx_pdu_bytes1; // Two status PDU (one with a NACK) uint32_t total_rx_pdu_bytes2 = (NBUFS)*data_pdu_size; // (NBUFS - 1 Lost + 1 RETX) * PDU size // SDU metrics TESTASSERT_EQ(5, metrics1.num_tx_sdus); TESTASSERT_EQ(0, metrics1.num_rx_sdus); TESTASSERT_EQ(5, metrics1.num_tx_sdu_bytes); TESTASSERT_EQ(0, metrics1.num_rx_sdu_bytes); TESTASSERT_EQ(0, metrics1.num_lost_sdus); // PDU metrics TESTASSERT_EQ(5 + 1, metrics1.num_tx_pdus); // One re-transmission TESTASSERT_EQ(2, metrics1.num_rx_pdus); // One status PDU TESTASSERT_EQ(total_tx_pdu_bytes1, metrics1.num_tx_pdu_bytes); // (NBUFS + 1 RETX) * PDU size TESTASSERT_EQ(total_rx_pdu_bytes1, metrics1.num_rx_pdu_bytes); // Two status PDU (one with a NACK) TESTASSERT_EQ(0, metrics1.num_lost_sdus); // No lost SDUs // PDU metrics TESTASSERT_EQ(0, metrics2.num_tx_sdus); TESTASSERT_EQ(5, metrics2.num_rx_sdus); TESTASSERT_EQ(0, metrics2.num_tx_sdu_bytes); TESTASSERT_EQ(5, metrics2.num_rx_sdu_bytes); TESTASSERT_EQ(0, metrics2.num_lost_sdus); // SDU metrics TESTASSERT_EQ(2, metrics2.num_tx_pdus); // Two status PDUs TESTASSERT_EQ(5, metrics2.num_rx_pdus); // 5 PDUs (6 tx'ed, but one was lost) TESTASSERT_EQ(total_tx_pdu_bytes2, metrics2.num_tx_pdu_bytes); // Two status PDU (one with a NACK) TESTASSERT_EQ(total_rx_pdu_bytes2, metrics2.num_rx_pdu_bytes); // (NBUFS - 1 Lost + 1 RETX) * PDU size TESTASSERT_EQ(0, metrics2.num_lost_sdus); // No lost SDUs return SRSRAN_SUCCESS; } /* * Test the basic segmentation of a single SDU. * A single SDU of 3 bytes is segmented into 3 PDUs */ int basic_segmentation_test(rlc_am_nr_sn_size_t sn_size) { rlc_am_tester tester; timer_handler timers(8); auto& test_logger = srslog::fetch_basic_logger("TESTER "); test_delimit_logger delimiter("basic segmentation"); 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(rlc1.get_tx()); rlc_am_nr_rx* rx1 = dynamic_cast(rlc1.get_rx()); rlc_am_nr_tx* tx2 = dynamic_cast(rlc2.get_tx()); rlc_am_nr_rx* rx2 = dynamic_cast(rlc2.get_rx()); // before configuring entity TESTASSERT_EQ(0, rlc1.get_buffer_state()); if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) { return -1; } if (not rlc2.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) { return -1; } // Push 1 SDU into RLC1 unique_byte_buffer_t sdu; constexpr uint32_t payload_size = 3; // Give the SDU the size of 3 bytes sdu = srsran::make_byte_buffer(); TESTASSERT(nullptr != sdu); sdu->msg[0] = 0; // Write the index into the buffer sdu->N_bytes = payload_size; // Give the SDU the size of 3 bytes sdu->md.pdcp_sn = 0; // PDCP SN for notifications rlc1.write_sdu(std::move(sdu)); // Read 3 PDUs constexpr uint16_t n_pdus = 3; unique_byte_buffer_t pdu_bufs[n_pdus]; uint32_t header_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3; constexpr uint32_t so_size = 2; constexpr uint32_t segment_size = 1; uint32_t pdu_size_first = header_size + segment_size; uint32_t pdu_size_continued = header_size + so_size + segment_size; for (int i = 0; i < n_pdus; i++) { pdu_bufs[i] = srsran::make_byte_buffer(); TESTASSERT(nullptr != pdu_bufs[i]); if (i == 0) { pdu_bufs[i]->N_bytes = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_first); TESTASSERT_EQ(pdu_size_first, pdu_bufs[i]->N_bytes); } else { pdu_bufs[i]->N_bytes = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_continued); TESTASSERT_EQ(pdu_size_continued, pdu_bufs[i]->N_bytes); } } // Write 3 PDUs into RLC2 for (int i = 0; i < n_pdus; i++) { rlc2.write_pdu(pdu_bufs[i]->msg, pdu_bufs[i]->N_bytes); } // Check statistics rlc_bearer_metrics_t metrics1 = rlc1.get_metrics(); rlc_bearer_metrics_t metrics2 = rlc2.get_metrics(); uint32_t total_rx_pdu_bytes = pdu_size_first + (n_pdus - 1) * pdu_size_continued; // 1 PDU (No SO) + 2 PDUs (with SO) // SDU metrics TESTASSERT_EQ(0, metrics2.num_tx_sdus); TESTASSERT_EQ(1, metrics2.num_rx_sdus); TESTASSERT_EQ(0, metrics2.num_tx_sdu_bytes); TESTASSERT_EQ(payload_size, metrics2.num_rx_sdu_bytes); TESTASSERT_EQ(0, metrics2.num_lost_sdus); // PDU metrics TESTASSERT_EQ(0, metrics2.num_tx_pdus); TESTASSERT_EQ(n_pdus, metrics2.num_rx_pdus); // 3 PDUs TESTASSERT_EQ(0, metrics2.num_tx_pdu_bytes); TESTASSERT_EQ(total_rx_pdu_bytes, metrics2.num_rx_pdu_bytes); // 1 PDU (No SO) + 2 PDUs (with SO) TESTASSERT_EQ(0, metrics2.num_lost_sdus); // No lost SDUs // Check state rlc_am_nr_tx_state_t state1_tx = tx1->get_tx_state(); TESTASSERT_EQ(1, state1_tx.tx_next); return SRSRAN_SUCCESS; } int segment_retx_test() { rlc_am_tester tester; timer_handler timers(8); byte_buffer_t pdu_bufs[NBUFS]; auto& test_logger = srslog::fetch_basic_logger("TESTER "); 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); test_delimit_logger delimiter("segment retx PDU"); rlc_am_nr_tx* tx1 = dynamic_cast(rlc1.get_tx()); rlc_am_nr_rx* rx1 = dynamic_cast(rlc1.get_rx()); rlc_am_nr_tx* tx2 = dynamic_cast(rlc2.get_tx()); rlc_am_nr_rx* rx2 = dynamic_cast(rlc2.get_rx()); // before configuring entity TESTASSERT_EQ(0, rlc1.get_buffer_state()); if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config())) { return -1; } if (not rlc2.configure(rlc_config_t::default_rlc_am_nr_config())) { return -1; } // Push 5 SDUs into RLC1 unique_byte_buffer_t sdu_bufs[NBUFS]; for (int i = 0; i < NBUFS; i++) { sdu_bufs[i] = srsran::make_byte_buffer(); sdu_bufs[i]->msg[0] = i; // Write the index into the buffer sdu_bufs[i]->N_bytes = 3; // Give each buffer a size of 3 bytes sdu_bufs[i]->md.pdcp_sn = i; // PDCP SN for notifications rlc1.write_sdu(std::move(sdu_bufs[i])); } TESTASSERT_EQ(25, rlc1.get_buffer_state()); // 2 Bytes * NBUFFS (header size) + NBUFFS * 3 (data) = 25 // Read 5 PDUs from RLC1 (1 byte each) for (int i = 0; i < NBUFS; i++) { uint32_t len = rlc1.read_pdu(pdu_bufs[i].msg, 5); // 2 bytes for header + 3 byte payload pdu_bufs[i].N_bytes = len; TESTASSERT_EQ(5, len); } TESTASSERT_EQ(0, rlc1.get_buffer_state()); // Write 5 PDUs into RLC2 for (int i = 0; i < NBUFS; i++) { if (i != 3) { rlc2.write_pdu(pdu_bufs[i].msg, pdu_bufs[i].N_bytes); // Don't write RLC_SN=3. } } // Only after t-reassembly has expired, will the status report include NACKs. TESTASSERT_EQ(3, rlc2.get_buffer_state()); { // Read status PDU from RLC2 byte_buffer_t status_buf; int len = rlc2.read_pdu(status_buf.msg, 5); status_buf.N_bytes = len; TESTASSERT_EQ(0, rlc2.get_buffer_state()); // Assert status is correct rlc_am_nr_status_pdu_t status_check = {}; rlc_am_nr_read_status_pdu(&status_buf, rlc_am_nr_sn_size_t::size12bits, &status_check); TESTASSERT_EQ(3, status_check.ack_sn); // 3 is the next expected SN (i.e. the lost packet.) // Write status PDU to RLC1 rlc1.write_pdu(status_buf.msg, status_buf.N_bytes); } // Step timers until reassambly timeout expires for (int cnt = 0; cnt < 35; cnt++) { timers.step_all(); } // t-reassembly has expired. There should be a NACK in the status report. TESTASSERT_EQ(5, rlc2.get_buffer_state()); { // Read status PDU from RLC2 byte_buffer_t status_buf; int len = rlc2.read_pdu(status_buf.msg, 5); status_buf.N_bytes = len; TESTASSERT_EQ(0, rlc2.get_buffer_state()); // Assert status is correct rlc_am_nr_status_pdu_t status_check = {}; rlc_am_nr_read_status_pdu(&status_buf, rlc_am_nr_sn_size_t::size12bits, &status_check); TESTASSERT_EQ(5, status_check.ack_sn); // 5 is the next expected SN. TESTASSERT_EQ(1, status_check.N_nack); // We lost one PDU. TESTASSERT_EQ(3, status_check.nacks[0].nack_sn); // Lost PDU SN=3. // Write status PDU to RLC1 rlc1.write_pdu(status_buf.msg, status_buf.N_bytes); // Check there is an Retx of SN=3 TESTASSERT_EQ(5, rlc1.get_buffer_state()); } { // Re-transmit PDU in 3 segments for (int i = 0; i < 3; i++) { byte_buffer_t retx_buf; uint32_t len = 0; if (i == 0) { len = rlc1.read_pdu(retx_buf.msg, 3); TESTASSERT_EQ(3, len); } else { len = rlc1.read_pdu(retx_buf.msg, 5); TESTASSERT_EQ(5, len); } retx_buf.N_bytes = len; rlc_am_nr_pdu_header_t header_check = {}; uint32_t hdr_len = rlc_am_nr_read_data_pdu_header(&retx_buf, rlc_am_nr_sn_size_t::size12bits, &header_check); // Double check header. TESTASSERT_EQ(3, header_check.sn); // Double check RETX SN if (i == 0) { TESTASSERT_EQ(rlc_nr_si_field_t::first_segment, header_check.si); } else if (i == 1) { TESTASSERT_EQ(rlc_nr_si_field_t::neither_first_nor_last_segment, header_check.si); } else { TESTASSERT_EQ(rlc_nr_si_field_t::last_segment, header_check.si); } rlc2.write_pdu(retx_buf.msg, retx_buf.N_bytes); } TESTASSERT(0 == rlc1.get_buffer_state()); } // Check statistics rlc_bearer_metrics_t metrics1 = rlc1.get_metrics(); rlc_bearer_metrics_t metrics2 = rlc2.get_metrics(); // SDU metrics TESTASSERT_EQ(5, metrics1.num_tx_sdus); TESTASSERT_EQ(0, metrics1.num_rx_sdus); TESTASSERT_EQ(15, metrics1.num_tx_sdu_bytes); TESTASSERT_EQ(0, metrics1.num_rx_sdu_bytes); TESTASSERT_EQ(0, metrics1.num_lost_sdus); // PDU metrics TESTASSERT_EQ(5 + 3, metrics1.num_tx_pdus); // 3 re-transmissions TESTASSERT_EQ(2, metrics1.num_rx_pdus); // Two status PDU TESTASSERT_EQ(38, metrics1.num_tx_pdu_bytes); // 2 Bytes * NBUFFS (header size) + NBUFFS * 3 (data) + // 3 (1 retx no SO) + 2 * 5 (2 retx with SO) = 38 TESTASSERT_EQ(3 + 5, metrics1.num_rx_pdu_bytes); // Two status PDU (one with a NACK) TESTASSERT_EQ(0, metrics1.num_lost_sdus); // No lost SDUs // PDU metrics TESTASSERT_EQ(0, metrics2.num_tx_sdus); TESTASSERT_EQ(5, metrics2.num_rx_sdus); TESTASSERT_EQ(0, metrics2.num_tx_sdu_bytes); TESTASSERT_EQ(15, metrics2.num_rx_sdu_bytes); // 5 SDUs, 3 bytes each TESTASSERT_EQ(0, metrics2.num_lost_sdus); // SDU metrics TESTASSERT_EQ(2, metrics2.num_tx_pdus); // Two status PDUs TESTASSERT_EQ(7, metrics2.num_rx_pdus); // 7 PDUs (8 tx'ed, but one was lost) TESTASSERT_EQ(5 + 3, metrics2.num_tx_pdu_bytes); // Two status PDU (one with a NACK) TESTASSERT_EQ(33, metrics2.num_rx_pdu_bytes); // 2 Bytes * (NBUFFS-1) (header size) + (NBUFFS-1) * 3 (data) // 3 (1 retx no SO) + 2 * 5 (2 retx with SO) = 33 TESTASSERT_EQ(0, metrics2.num_lost_sdus); // No lost SDUs // Check state rlc_am_nr_rx_state_t state2_rx = rx2->get_rx_state(); TESTASSERT_EQ(5, state2_rx.rx_next); return SRSRAN_SUCCESS; } int retx_segment_test() { rlc_am_tester tester; timer_handler timers(8); auto& test_logger = srslog::fetch_basic_logger("TESTER "); 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); test_delimit_logger delimiter("retx segment PDU"); rlc_am_nr_tx* tx1 = dynamic_cast(rlc1.get_tx()); rlc_am_nr_rx* rx1 = dynamic_cast(rlc1.get_rx()); rlc_am_nr_tx* tx2 = dynamic_cast(rlc2.get_tx()); rlc_am_nr_rx* rx2 = dynamic_cast(rlc2.get_rx()); // before configuring entity TESTASSERT(0 == rlc1.get_buffer_state()); if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config())) { return -1; } if (not rlc2.configure(rlc_config_t::default_rlc_am_nr_config())) { return -1; } int n_sdu_bufs = 5; int n_pdu_bufs = 15; // Push 5 SDUs into RLC1 std::vector sdu_bufs(n_sdu_bufs); for (int i = 0; i < n_sdu_bufs; i++) { sdu_bufs[i] = srsran::make_byte_buffer(); sdu_bufs[i]->msg[0] = i; // Write the index into the buffer sdu_bufs[i]->N_bytes = 3; // Give each buffer a size of 3 bytes sdu_bufs[i]->md.pdcp_sn = i; // PDCP SN for notifications rlc1.write_sdu(std::move(sdu_bufs[i])); } TESTASSERT(25 == rlc1.get_buffer_state()); // 2 Bytes * NBUFFS (header size) + NBUFFS * 3 (data) = 25 // Read 15 PDUs from RLC1 std::vector pdu_bufs(n_pdu_bufs); for (int i = 0; i < n_pdu_bufs; i++) { pdu_bufs[i] = srsran::make_byte_buffer(); if (i == 0 || i == 3 || i == 6 || i == 9 || i == 12) { // First segment, no SO uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, 3); // 2 bytes for header + 1 byte payload pdu_bufs[i]->N_bytes = len; TESTASSERT_EQ(3, len); } else { // Middle or last segment, SO present uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, 5); // 4 bytes for header + 1 byte payload pdu_bufs[i]->N_bytes = len; TESTASSERT_EQ(5, len); } } TESTASSERT_EQ(0, rlc1.get_buffer_state()); // Write 15 - 3 PDUs into RLC2 for (int i = 0; i < n_pdu_bufs; i++) { if (i != 3 && i != 7 && i != 11) { rlc2.write_pdu(pdu_bufs[i]->msg, pdu_bufs[i]->N_bytes); // Lose first segment of RLC_SN=1. } } // Only after t-reassembly has expired, will the status report include NACKs. TESTASSERT_EQ(3, rlc2.get_buffer_state()); { // Read status PDU from RLC2 byte_buffer_t status_buf; int len = rlc2.read_pdu(status_buf.msg, 5); status_buf.N_bytes = len; TESTASSERT_EQ(0, rlc2.get_buffer_state()); // Assert status is correct rlc_am_nr_status_pdu_t status_check = {}; rlc_am_nr_read_status_pdu(&status_buf, rlc_am_nr_sn_size_t::size12bits, &status_check); TESTASSERT_EQ(1, status_check.ack_sn); // 1 is the next expected SN (i.e. the first lost packet.) // Write status PDU to RLC1 rlc1.write_pdu(status_buf.msg, status_buf.N_bytes); } // Step timers until reassambly timeout expires for (int cnt = 0; cnt < 35; cnt++) { timers.step_all(); } // t-reassembly has expired. There should be a NACK in the status report. // There should be 3 NACKs with SO_start and SO_end TESTASSERT_EQ(21, rlc2.get_buffer_state()); // 3 bytes for fixed header (ACK+E1) + 3 * 6 for NACK with SO = 21. { // Read status PDU from RLC2 byte_buffer_t status_buf; int len = rlc2.read_pdu(status_buf.msg, 21); status_buf.N_bytes = len; TESTASSERT_EQ(0, rlc2.get_buffer_state()); // Assert status is correct rlc_am_nr_status_pdu_t status_check = {}; rlc_am_nr_read_status_pdu(&status_buf, rlc_am_nr_sn_size_t::size12bits, &status_check); TESTASSERT_EQ(5, status_check.ack_sn); // 5 is the next expected SN. TESTASSERT_EQ(3, status_check.N_nack); // We lost one PDU. TESTASSERT_EQ(1, status_check.nacks[0].nack_sn); // Lost SDU on SN=1. TESTASSERT_EQ(true, status_check.nacks[0].has_so); // Lost SDU on SN=1. TESTASSERT_EQ(0, status_check.nacks[0].so_start); // Lost SDU on SN=1. TESTASSERT_EQ(0, status_check.nacks[0].so_end); // Lost SDU on SN=1. TESTASSERT_EQ(2, status_check.nacks[1].nack_sn); // Lost SDU on SN=1. TESTASSERT_EQ(true, status_check.nacks[1].has_so); // Lost SDU on SN=1. TESTASSERT_EQ(1, status_check.nacks[1].so_start); // Lost SDU on SN=1. TESTASSERT_EQ(1, status_check.nacks[1].so_end); // Lost SDU on SN=1. TESTASSERT_EQ(3, status_check.nacks[2].nack_sn); // Lost SDU on SN=1. TESTASSERT_EQ(true, status_check.nacks[2].has_so); // Lost SDU on SN=1. TESTASSERT_EQ(2, status_check.nacks[2].so_start); // Lost SDU on SN=1. TESTASSERT_EQ(0xFFFF, status_check.nacks[2].so_end); // Lost SDU on SN=1. // Write status PDU to RLC1 rlc1.write_pdu(status_buf.msg, status_buf.N_bytes); // Check there is an Retx of SN=3 TESTASSERT_EQ(5, rlc1.get_buffer_state()); } { // Re-transmit the 3 lost segments for (int i = 0; i < 3; i++) { byte_buffer_t retx_buf; uint32_t len = 0; if (i == 0) { len = rlc1.read_pdu(retx_buf.msg, 3); TESTASSERT_EQ(3, len); } else { len = rlc1.read_pdu(retx_buf.msg, 5); TESTASSERT_EQ(5, len); } retx_buf.N_bytes = len; rlc_am_nr_pdu_header_t header_check = {}; uint32_t hdr_len = rlc_am_nr_read_data_pdu_header(&retx_buf, rlc_am_nr_sn_size_t::size12bits, &header_check); // Double check header. if (i == 0) { TESTASSERT_EQ(1, header_check.sn); // Double check RETX SN TESTASSERT_EQ(rlc_nr_si_field_t::first_segment, header_check.si); } else if (i == 1) { TESTASSERT_EQ(2, header_check.sn); // Double check RETX SN TESTASSERT_EQ(rlc_nr_si_field_t::neither_first_nor_last_segment, header_check.si); } else { TESTASSERT_EQ(3, header_check.sn); // Double check RETX SN TESTASSERT_EQ(rlc_nr_si_field_t::last_segment, header_check.si); } rlc2.write_pdu(retx_buf.msg, retx_buf.N_bytes); } TESTASSERT_EQ(0, rlc1.get_buffer_state()); } // Check statistics rlc_bearer_metrics_t metrics1 = rlc1.get_metrics(); rlc_bearer_metrics_t metrics2 = rlc2.get_metrics(); // SDU metrics TESTASSERT_EQ(5, metrics1.num_tx_sdus); TESTASSERT_EQ(0, metrics1.num_rx_sdus); TESTASSERT_EQ(15, metrics1.num_tx_sdu_bytes); TESTASSERT_EQ(0, metrics1.num_rx_sdu_bytes); TESTASSERT_EQ(0, metrics1.num_lost_sdus); // PDU metrics TESTASSERT_EQ(15 + 3, metrics1.num_tx_pdus); // 15 PDUs + 3 re-transmissions TESTASSERT_EQ(2, metrics1.num_rx_pdus); // Two status PDU TESTASSERT_EQ(78, metrics1.num_tx_pdu_bytes); // 3 Bytes * 5 (5 PDUs without SO) + 10 * 5 (10 PDUs with SO) // 3 (1 retx no SO) + 2 * 5 (2 retx with SO) = 78 TESTASSERT_EQ(24, metrics1.num_rx_pdu_bytes); // Two status PDU. One with just an ack (3 bytes) // Another with 3 NACKs all with SO. (3 + 3*6 bytes) TESTASSERT_EQ(0, metrics1.num_lost_sdus); // No lost SDUs // PDU metrics TESTASSERT_EQ(0, metrics2.num_tx_sdus); TESTASSERT_EQ(5, metrics2.num_rx_sdus); TESTASSERT_EQ(0, metrics2.num_tx_sdu_bytes); TESTASSERT_EQ(15, metrics2.num_rx_sdu_bytes); // 5 SDUs, 3 bytes each TESTASSERT_EQ(0, metrics2.num_lost_sdus); // SDU metrics TESTASSERT_EQ(2, metrics2.num_tx_pdus); // Two status PDUs TESTASSERT_EQ(15, metrics2.num_rx_pdus); // 15 PDUs (18 tx'ed, but three were lost) TESTASSERT_EQ(24, metrics2.num_tx_pdu_bytes); // Two status PDU. One with just an ack (3 bytes) // Another with 3 NACKs all with SO. (3 + 3*6 bytes) TESTASSERT_EQ(65, metrics2.num_rx_pdu_bytes); // 3 Bytes (header + data size, without SO) * 5 (N PDUs without SO) // 5 bytes (header + data size, with SO) * 10 (N PDUs with SO) // = 81 bytes TESTASSERT_EQ(0, metrics2.num_lost_sdus); // No lost SDUs // Check state rlc_am_nr_rx_state_t state2_rx = rx2->get_rx_state(); TESTASSERT_EQ(5, state2_rx.rx_next); return SRSRAN_SUCCESS; } // This test checks whether RLC informs upper layer when max retransmission has been reached // due to lost SDUs as a whole int max_retx_lost_sdu_test() { rlc_am_tester tester; timer_handler timers(8); int len = 0; auto& test_logger = srslog::fetch_basic_logger("TESTER "); rlc_am rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers); srslog::fetch_basic_logger("RLC_AM_1").set_hex_dump_max_size(100); srslog::fetch_basic_logger("RLC").set_hex_dump_max_size(100); test_delimit_logger delimiter("max retx lost SDU"); const rlc_config_t rlc_cfg = rlc_config_t::default_rlc_am_nr_config(); if (not rlc1.configure(rlc_cfg)) { return SRSRAN_ERROR; } // Push 2 SDUs into RLC1 const uint32_t n_sdus = 2; unique_byte_buffer_t sdu_bufs[n_sdus]; for (uint32_t i = 0; i < n_sdus; i++) { sdu_bufs[i] = srsran::make_byte_buffer(); sdu_bufs[i]->msg[0] = i; // Write the index into the buffer sdu_bufs[i]->N_bytes = 1; // Give each buffer a size of 1 byte sdu_bufs[i]->md.pdcp_sn = i; // PDCP SN for notifications rlc1.write_sdu(std::move(sdu_bufs[i])); } // Read 2 PDUs from RLC1 (1 byte each) const uint32_t n_pdus = 2; byte_buffer_t pdu_bufs[n_pdus]; for (uint32_t i = 0; i < n_pdus; i++) { len = rlc1.read_pdu(pdu_bufs[i].msg, 3); // 2 byte header + 1 byte payload pdu_bufs[i].N_bytes = len; } TESTASSERT(0 == rlc1.get_buffer_state()); // Fake status PDU that ack SN=1 and nack SN=0 rlc_am_nr_status_pdu_t fake_status = {}; fake_status.ack_sn = 2; // delivered up to SN=1 fake_status.N_nack = 1; // one SN was lost fake_status.nacks[0].nack_sn = 0; // it was SN=0 that was lost // pack into PDU byte_buffer_t status_pdu; rlc_am_nr_write_status_pdu(fake_status, rlc_cfg.am_nr.tx_sn_field_length, &status_pdu); // Exceed the number of tolerated retransmissions by one additional retransmission // to trigger notification of the higher protocol layers. Note that the initial transmission // (before starting retransmissions) does not count. See TS 38.322 Sec. 5.3.2 for (uint32_t retx_count = 0; retx_count < rlc_cfg.am_nr.max_retx_thresh + 1; ++retx_count) { // we've not yet reached max attempts TESTASSERT(tester.max_retx_triggered == false); // Write status PDU to RLC1 rlc1.write_pdu(status_pdu.msg, status_pdu.N_bytes); byte_buffer_t pdu_buf; len = rlc1.read_pdu(pdu_buf.msg, 3); // 2 byte header + 1 byte payload } // Now maxRetx should have been triggered TESTASSERT(tester.max_retx_triggered == true); return SRSRAN_SUCCESS; } // This test checks whether RLC informs upper layer when max retransmission has been reached // due to lost SDU segments int max_retx_lost_segments_test() { rlc_am_tester tester; timer_handler timers(8); int len = 0; auto& test_logger = srslog::fetch_basic_logger("TESTER "); rlc_am rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers); srslog::fetch_basic_logger("RLC_AM_1").set_hex_dump_max_size(100); srslog::fetch_basic_logger("RLC").set_hex_dump_max_size(100); test_delimit_logger delimiter("max retx lost SDU segment"); const rlc_config_t rlc_cfg = rlc_config_t::default_rlc_am_nr_config(); if (not rlc1.configure(rlc_cfg)) { return SRSRAN_ERROR; } // Push 2 SDUs into RLC1 const uint32_t n_sdus = 2; unique_byte_buffer_t sdu_bufs[n_sdus]; for (uint32_t i = 0; i < n_sdus; i++) { sdu_bufs[i] = srsran::make_byte_buffer(); sdu_bufs[i]->msg[0] = i; // Write the index into the buffer sdu_bufs[i]->N_bytes = 20; // Give each buffer a size of 20 bytes sdu_bufs[i]->md.pdcp_sn = i; // PDCP SN for notifications rlc1.write_sdu(std::move(sdu_bufs[i])); } // Read 2*2=4 PDUs from RLC1 and limit to 15 byte to force segmentation in two parts: // Segment 1: 2 byte header + 13 byte payload; space fully used // Segment 2: 4 byte header + 7 byte payload; space not fully used, 4 bytes left over const uint32_t n_pdus = 4; byte_buffer_t pdu_bufs[n_pdus]; for (uint32_t i = 0; i < n_pdus; i++) { len = rlc1.read_pdu(pdu_bufs[i].msg, 15); pdu_bufs[i].N_bytes = len; } TESTASSERT(0 == rlc1.get_buffer_state()); // Fake status PDU that ack SN=1 and nack {SN=0 segment 0, SN=0 segment 1} rlc_am_nr_status_pdu_t status_lost_both_segments = {}; status_lost_both_segments.ack_sn = 2; // delivered up to SN=1 status_lost_both_segments.N_nack = 2; // two segments lost status_lost_both_segments.nacks[0].nack_sn = 0; // it was SN=0 that was lost status_lost_both_segments.nacks[0].has_so = true; // this NACKs a segment status_lost_both_segments.nacks[0].so_start = 0; // segment starts at (and includes) byte 0 status_lost_both_segments.nacks[0].so_end = 12; // segment ends at (and includes) byte 12 status_lost_both_segments.nacks[1].nack_sn = 0; // it was SN=0 that was lost status_lost_both_segments.nacks[1].has_so = true; // this NACKs a segment status_lost_both_segments.nacks[1].so_start = 13; // segment starts at (and includes) byte 13 status_lost_both_segments.nacks[1].so_end = 19; // segment ends at (and includes) byte 19 // pack into PDU byte_buffer_t status_pdu_lost_both_segments; rlc_am_nr_write_status_pdu( status_lost_both_segments, rlc_cfg.am_nr.tx_sn_field_length, &status_pdu_lost_both_segments); // Fake status PDU that ack SN=1 and nack {SN=0 segment 2} rlc_am_nr_status_pdu_t status_lost_second_segment = {}; status_lost_second_segment.ack_sn = 2; // delivered up to SN=1 status_lost_second_segment.N_nack = 1; // one SN was lost status_lost_second_segment.nacks[0].nack_sn = 0; // it was SN=0 that was lost status_lost_second_segment.nacks[0].has_so = true; // this NACKs a segment status_lost_second_segment.nacks[0].so_start = 13; // segment starts at (and includes) byte 13 status_lost_second_segment.nacks[0].so_end = 19; // segment ends at (and includes) byte 19 // pack into PDU byte_buffer_t status_pdu_lost_second_segment; rlc_am_nr_write_status_pdu( status_lost_second_segment, rlc_cfg.am_nr.tx_sn_field_length, &status_pdu_lost_second_segment); // Exceed the number of tolerated retransmissions by one additional retransmission // to trigger notification of the higher protocol layers. Note that the initial transmission // (before starting retransmissions) does not count. See TS 38.322 Sec. 5.3.2 for (uint32_t retx_count = 0; retx_count < rlc_cfg.am_nr.max_retx_thresh + 1; ++retx_count) { byte_buffer_t pdu_buf; // we've not yet reached max attempts TESTASSERT(tester.max_retx_triggered == false); if (retx_count < rlc_cfg.am_nr.max_retx_thresh / 2) { // Send NACK for segment 1 and segment 2 // Although two segments, this must count as one retransmission, // because both segments NACK the same SDU in the same status message. rlc1.write_pdu(status_pdu_lost_both_segments.msg, status_pdu_lost_both_segments.N_bytes); // read the retransmitted PDUs len = rlc1.read_pdu(pdu_buf.msg, 15); // 2 byte header + 13 byte payload len = rlc1.read_pdu(pdu_buf.msg, 15); // 4 byte header + 7 byte payload } else { // Send NACK for segment 2 (assume at least segment 1 was finally received) rlc1.write_pdu(status_pdu_lost_second_segment.msg, status_pdu_lost_second_segment.N_bytes); // read the retransmitted PDUs len = rlc1.read_pdu(pdu_buf.msg, 15); // 4 byte header + 7 byte payload } } // Now maxRetx should have been triggered TESTASSERT(tester.max_retx_triggered == true); return SRSRAN_SUCCESS; } // This test checks the correct functioning of RLC discard functionality int discard_test() { rlc_am_tester tester; timer_handler timers(8); auto& test_logger = srslog::fetch_basic_logger("TESTER "); 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); srslog::fetch_basic_logger("RLC_AM_1").set_hex_dump_max_size(100); srslog::fetch_basic_logger("RLC_AM_2").set_hex_dump_max_size(100); srslog::fetch_basic_logger("RLC").set_hex_dump_max_size(100); if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config())) { return SRSRAN_ERROR; } if (not rlc2.configure(rlc_config_t::default_rlc_am_nr_config())) { return SRSRAN_ERROR; } // Test discarding the single SDU from the queue { uint32_t num_tx_sdus = 1; for (uint32_t i = 0; i < num_tx_sdus; ++i) { // Write SDU unique_byte_buffer_t sdu = srsran::make_byte_buffer(); TESTASSERT(sdu != nullptr); sdu->N_bytes = 5; for (uint32_t k = 0; k < sdu->N_bytes; ++k) { sdu->msg[k] = i; // Write the index into the buffer } sdu->md.pdcp_sn = i; rlc1.write_sdu(std::move(sdu)); } } rlc1.discard_sdu(0); // Try to discard PDCP_SN=0 TESTASSERT(rlc1.has_data() == false); // Test discarding two SDUs in the middle (SN=3) and end (SN=9) of the queue and read PDUs after { uint32_t num_tx_sdus = 10; for (uint32_t i = 0; i < num_tx_sdus; ++i) { // Write SDU unique_byte_buffer_t sdu = srsran::make_byte_buffer(); TESTASSERT(sdu != nullptr); sdu->N_bytes = 7; for (uint32_t k = 0; k < sdu->N_bytes; ++k) { sdu->msg[k] = i; // Write the index into the buffer } sdu->md.pdcp_sn = i; rlc1.write_sdu(std::move(sdu)); } } TESTASSERT(rlc1.get_buffer_state() == 90); // 10 * (2B Header + 7B Payload) rlc1.discard_sdu(3); // Try to discard PDCP_SN=3 TESTASSERT(rlc1.has_data() == true); TESTASSERT(rlc1.get_buffer_state() == 81); rlc1.discard_sdu(9); // Try to discard PDCP_SN=9 TESTASSERT(rlc1.has_data() == true); TESTASSERT(rlc1.get_buffer_state() == 72); { uint32_t num_tx_sdus = 8; for (uint32_t i = 0; i < num_tx_sdus; ++i) { unique_byte_buffer_t pdu = srsran::make_byte_buffer(); uint32_t len = rlc1.read_pdu(pdu->msg, 50); // sufficient space to read without segmentation pdu->N_bytes = len; TESTASSERT((2 + 7) == len); // Check that we don't have any SN gaps rlc_am_nr_pdu_header_t header = {}; rlc_am_nr_read_data_pdu_header(pdu.get(), rlc_am_nr_sn_size_t::size12bits, &header); TESTASSERT(header.sn == i); } } TESTASSERT(rlc1.has_data() == false); srslog::fetch_basic_logger("TEST").info("Received %zd SDUs", tester.sdus.size()); // Test discarding non-existing SDU from the queue { uint32_t num_tx_sdus = 3; for (uint32_t i = 0; i < num_tx_sdus; ++i) { // Write SDU unique_byte_buffer_t sdu = srsran::make_byte_buffer(); TESTASSERT(sdu != nullptr); sdu->N_bytes = 7; for (uint32_t k = 0; k < sdu->N_bytes; ++k) { sdu->msg[k] = i; // Write the index into the buffer } sdu->md.pdcp_sn = i; rlc1.write_sdu(std::move(sdu)); } } TESTASSERT(rlc1.get_buffer_state() == 27); // 3 * (2B Header + 7B Payload) rlc1.discard_sdu(8); // Try to discard PDCP_SN=8, which doesn't exist TESTASSERT(rlc1.get_buffer_state() == 27); // 3 * (2B Header + 7B Payload) return SRSRAN_SUCCESS; } int main() { // Setup the log message spy to intercept error and warning log entries from RLC if (!srslog::install_custom_sink(srsran::log_sink_message_spy::name(), std::unique_ptr( new srsran::log_sink_message_spy(srslog::get_default_log_formatter())))) { return SRSRAN_ERROR; } auto* spy = static_cast(srslog::find_sink(srsran::log_sink_message_spy::name())); if (spy == nullptr) { return SRSRAN_ERROR; } srslog::set_default_sink(*spy); auto& logger_rlc1 = srslog::fetch_basic_logger("RLC_AM_1", *spy, false); auto& logger_rlc2 = srslog::fetch_basic_logger("RLC_AM_2", *spy, false); logger_rlc1.set_hex_dump_max_size(100); logger_rlc2.set_hex_dump_max_size(100); logger_rlc1.set_level(srslog::basic_levels::debug); logger_rlc2.set_level(srslog::basic_levels::debug); // start log back-end srslog::init(); TESTASSERT(window_checker_test(rlc_am_nr_sn_size_t::size12bits) == SRSRAN_SUCCESS); TESTASSERT(window_checker_test(rlc_am_nr_sn_size_t::size18bits) == SRSRAN_SUCCESS); TESTASSERT(retx_segmentation_required_checker_test(rlc_am_nr_sn_size_t::size12bits) == SRSRAN_SUCCESS); TESTASSERT(retx_segmentation_required_checker_test(rlc_am_nr_sn_size_t::size18bits) == SRSRAN_SUCCESS); TESTASSERT(basic_test(rlc_am_nr_sn_size_t::size12bits) == SRSRAN_SUCCESS); TESTASSERT(basic_test(rlc_am_nr_sn_size_t::size18bits) == SRSRAN_SUCCESS); TESTASSERT(lost_pdu_test(rlc_am_nr_sn_size_t::size12bits) == SRSRAN_SUCCESS); TESTASSERT(lost_pdu_test(rlc_am_nr_sn_size_t::size18bits) == SRSRAN_SUCCESS); TESTASSERT(basic_segmentation_test(rlc_am_nr_sn_size_t::size12bits) == SRSRAN_SUCCESS); TESTASSERT(basic_segmentation_test(rlc_am_nr_sn_size_t::size18bits) == SRSRAN_SUCCESS); TESTASSERT(segment_retx_test() == SRSRAN_SUCCESS); TESTASSERT(retx_segment_test() == SRSRAN_SUCCESS); TESTASSERT(max_retx_lost_sdu_test() == SRSRAN_SUCCESS); TESTASSERT(max_retx_lost_segments_test() == SRSRAN_SUCCESS); TESTASSERT(discard_test() == SRSRAN_SUCCESS); return SRSRAN_SUCCESS; }