srsLTE/lib/test/rlc/rlc_am_nr_test.cc

3415 lines
137 KiB
C++

/**
*
* \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(true, nullptr);
timer_handler timers(8);
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("window checkers ({} 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_nr_tx* tx = dynamic_cast<rlc_am_nr_tx*>(rlc1.get_tx());
rlc_am_nr_rx* rx = dynamic_cast<rlc_am_nr_rx*>(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(true, nullptr);
timer_handler timers(8);
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("retx segmentation required checkers ({} 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_nr_tx* tx = dynamic_cast<rlc_am_nr_tx*>(rlc1.get_tx());
rlc_am_nr_rx* rx = dynamic_cast<rlc_am_nr_rx*>(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(true, nullptr);
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 ({} 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());
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;
}
// after configuring entity
TESTASSERT_EQ(0, rlc1.get_buffer_state());
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(sn_size);
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_utilization());
// 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.
* No further status reports shall be issued.
*/
int lost_pdu_test(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 ");
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 ({} bit SN)", to_number(sn_size));
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;
if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) {
return -1;
}
rlc_config_t rlc2_config = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
if (not rlc2.configure(rlc2_config)) {
return -1;
}
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
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(sn_size);
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(sn_size);
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.nacks.size()); // 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);
// Polling bit on the RETX should be required, as the buffers are not empty.
rlc2.write_pdu(retx_buf.msg, retx_buf.N_bytes);
TESTASSERT_EQ(0, rlc2.get_buffer_state()); // t-StatusProhibit is still running
}
// Step timers until t-StatusProhibit expires
for (int cnt = 0; cnt < 8; cnt++) {
timers.step_all();
}
TESTASSERT_EQ(3, rlc2.get_buffer_state()); // t-StatusProhibit no longer running
{
// Double check status report
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(sn_size);
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(0, status_check.nacks.size()); // All PDUs are acked now
}
{
// rlc2 should not issue further status PDUs as time passes (even after expiry of t_status_prohibit)
int32_t checktime = 2 * rlc2_config.am_nr.t_status_prohibit;
for (int cnt = 0; cnt < checktime; cnt++) {
timers.step_all();
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 =
3 * status_pdu_ack_size + status_pdu_nack_size; // Three status PDU (one with a NACK, two without)
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(3, metrics2.num_tx_pdus); // Three 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); // Three status PDU (one with a NACK, two without)
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 loss of a single PDU with NACK duplicate
* NACK should be visible in the status report.
*
* Retx after NACK should be present too.
* No further status reports shall be issued.
*/
int lost_pdu_duplicated_nack_test(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 ");
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 with NACK duplicate ({} bit SN)", to_number(sn_size));
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;
if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) {
return -1;
}
rlc_config_t rlc2_config = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
if (not rlc2.configure(rlc2_config)) {
return -1;
}
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
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(sn_size);
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);
// Write duplicated status PDU to RLC1
rlc1.write_pdu(status_buf.msg, status_buf.N_bytes);
// Check there is nothing pending in RLC1
TESTASSERT_EQ(0, rlc1.get_buffer_state());
}
// 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(sn_size);
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.nacks.size()); // 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);
// Write duplicated status PDU to RLC1
rlc1.write_pdu(status_buf.msg, status_buf.N_bytes);
// Check there is only one 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()); // Status report shoud be required, as the TX buffers are now empty.
}
// Step timers until t-StatusProhibit expires
for (int cnt = 0; cnt < 8; cnt++) {
timers.step_all();
}
TESTASSERT_EQ(3, rlc2.get_buffer_state()); // t-StatusProhibit no longer running
{
// Double check status report
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(sn_size);
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(0, status_check.nacks.size()); // All PDUs are acked now
}
{
// rlc2 should not issue further status PDUs as time passes (even after expiry of t_status_prohibit)
int32_t checktime = 2 * rlc2_config.am_nr.t_status_prohibit;
for (int cnt = 0; cnt < checktime; cnt++) {
timers.step_all();
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 = 4 * status_pdu_ack_size + 2 * status_pdu_nack_size; // 4 status PDU (2 with a NACK)
uint32_t total_tx_pdu_bytes2 =
3 * status_pdu_ack_size + status_pdu_nack_size; // Three status PDU (one with a NACK, two without)
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(4, metrics1.num_rx_pdus); // 4 status PDUs
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(3, metrics2.num_tx_pdus); // Three 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); // Three status PDU (one with a NACK, two without)
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 loss of multiple PDUs.
* NACKs for all missing PDUs should be visible in buffer state -- but we enforce
* a trimmed status PDU by providing little space for the whole status PDU.
* Retx after NACK should be present too.
* Further status report shall contain the trimmed NACK.
* Another Retx after NACK should be present.
* No further status reports shall be issued.
*/
int lost_pdus_trimmed_nack_test(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 ");
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 PDUs and trimmed NACKs ({} bit SN)", to_number(sn_size));
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;
if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) {
return -1;
}
rlc_config_t rlc2_config = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
if (not rlc2.configure(rlc2_config)) {
return -1;
}
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
basic_test_tx(&rlc1, pdu_bufs, sn_size);
// Write 5 PDUs into RLC2
for (int i = 0; i < NBUFS; i++) {
if (i != 1 && i != 3) {
rlc2.write_pdu(pdu_bufs[i].msg, pdu_bufs[i].N_bytes); // Don't write RLC_SN=1 and 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(sn_size);
rlc_am_nr_read_status_pdu(&status_buf, sn_size, &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();
}
// Step timers until reassambly timeout expires
for (int cnt = 0; cnt < 35; cnt++) {
timers.step_all();
}
// t-reassembly has expired. There should be two NACKs 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;
uint32_t expected_size = status_pdu_ack_size + 2 * status_pdu_nack_size;
TESTASSERT_EQ(expected_size, rlc2.get_buffer_state());
{
// Read status PDU from RLC2, enforce to trimming by providing little space (expected_size - 1)
// to drop the second NACK.
byte_buffer_t status_buf;
uint32_t len = rlc2.read_pdu(status_buf.msg, expected_size - 1);
status_buf.N_bytes = len;
expected_size = status_pdu_ack_size + 1 * status_pdu_nack_size; // only one NACK left
TESTASSERT_EQ(len, expected_size);
// Assert status is correct
rlc_am_nr_status_pdu_t status_check(sn_size);
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 (after trimming)
TESTASSERT_EQ(1, status_check.nacks.size()); // Expect only one NACK left
TESTASSERT_EQ(1, status_check.nacks[0].nack_sn); // The NACK'ed SN is 1.
// Write status PDU to RLC1
rlc1.write_pdu(status_buf.msg, status_buf.N_bytes);
// Check there is an Retx of SN=1
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);
expected_size = status_pdu_ack_size + 1 * status_pdu_nack_size;
TESTASSERT_EQ(0, rlc2.get_buffer_state()); // Status report should now include the chopped NACK
}
// Step timers until t-StatusProhibit expires
for (int cnt = 0; cnt < 8; cnt++) {
timers.step_all();
}
TESTASSERT_EQ(expected_size, rlc2.get_buffer_state()); // t-StatusProhibit no longer running
{
// Double check status report
byte_buffer_t status_buf;
uint32_t len = rlc2.read_pdu(status_buf.msg, expected_size);
status_buf.N_bytes = len;
expected_size = status_pdu_ack_size + 1 * status_pdu_nack_size; // the remaining NACK
TESTASSERT_EQ(len, expected_size);
// Nothing else pending
TESTASSERT_EQ(0, rlc2.get_buffer_state());
// Assert status is correct
rlc_am_nr_status_pdu_t status_check(sn_size);
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.nacks.size()); // Expect only the second NACK
TESTASSERT_EQ(3, status_check.nacks[0].nack_sn); // The NACK'ed SN is 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);
expected_size = status_pdu_ack_size;
TESTASSERT_EQ(0, rlc2.get_buffer_state()); // Status report should have no NACKs
}
// Step timers until t-StatusProhibit expires
for (int cnt = 0; cnt < 8; cnt++) {
timers.step_all();
}
TESTASSERT_EQ(expected_size, rlc2.get_buffer_state()); // t-StatusProhibit no longer running
{
// Double check status report
byte_buffer_t status_buf;
int len = rlc2.read_pdu(status_buf.msg, expected_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(sn_size);
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(0, status_check.nacks.size()); // All PDUs are acked now
}
{
// rlc2 should not issue further status PDUs as time passes (even after expiry of t_status_prohibit)
int32_t checktime = 2 * rlc2_config.am_nr.t_status_prohibit;
for (int cnt = 0; cnt < checktime; cnt++) {
timers.step_all();
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 + 2) * data_pdu_size; // (NBUFS + 2 RETX) * PDU size
uint32_t total_rx_pdu_bytes1 = 3 * status_pdu_ack_size + 2 * status_pdu_nack_size; // 3 status PDUs (2 with one NACK)
uint32_t total_tx_pdu_bytes2 =
4 * status_pdu_ack_size + 2 * status_pdu_nack_size; // 4 status PDUs (2 with one NACK, two without)
uint32_t total_rx_pdu_bytes2 = (NBUFS)*data_pdu_size; // (NBUFS - 2 Lost + 2 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 + 2, metrics1.num_tx_pdus); // One re-transmission
TESTASSERT_EQ(3, metrics1.num_rx_pdus); // 3 status PDUs
TESTASSERT_EQ(total_tx_pdu_bytes1, metrics1.num_tx_pdu_bytes); // (NBUFS + 2 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(4, metrics2.num_tx_pdus); // 4 status PDUs
TESTASSERT_EQ(5, metrics2.num_rx_pdus); // 5 PDUs (7 tx'ed, but 2 were lost)
TESTASSERT_EQ(total_tx_pdu_bytes2, metrics2.num_tx_pdu_bytes); // Three status PDU (one with a NACK, two without)
TESTASSERT_EQ(total_rx_pdu_bytes2, metrics2.num_rx_pdu_bytes); // (NBUFS - 2 Lost + 2 RETX) * PDU size
TESTASSERT_EQ(0, metrics2.num_lost_sdus); // No lost SDUs
return SRSRAN_SUCCESS;
}
/*
* Test if retx queue is cleared of SDUs that are ACK'ed by a late/delayed ACK.
*/
int clean_retx_queue_of_acked_sdus_test(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 ");
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("Clean retx_queue of SDUs that are ACK'ed by a late/delayed ACK ({} bit SN)",
to_number(sn_size));
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;
if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) {
return -1;
}
rlc_config_t rlc2_config = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
if (not rlc2.configure(rlc2_config)) {
return -1;
}
rlc_am_nr_tx* rlc1_tx = dynamic_cast<rlc_am_nr_tx*>(rlc1.get_tx());
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
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(sn_size);
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);
// Check there is nothing pending in RLC1
TESTASSERT_EQ(0, rlc1.get_buffer_state());
}
// 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(sn_size);
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.nacks.size()); // 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 only one Retx of SN=3
TESTASSERT_EQ(data_pdu_size, rlc1.get_buffer_state());
}
// now we deliver the late PDU SN=3 to rlc2
rlc2.write_pdu(pdu_bufs[3].msg, pdu_bufs[3].N_bytes);
// Check there is only one Retx of SN=3
TESTASSERT_EQ(data_pdu_size, rlc1.get_buffer_state());
TESTASSERT_EQ(1, rlc1_tx->get_retx_queue_size());
// Step timers until reassambly timeout expires
for (int cnt = 0; cnt < 35; cnt++) {
timers.step_all();
}
// t-reassembly has expired. There should be an ACK in the status report.
TESTASSERT_EQ(status_pdu_ack_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_buf.N_bytes = len;
TESTASSERT_EQ(0, rlc2.get_buffer_state());
// Assert status is correct
rlc_am_nr_status_pdu_t status_check(sn_size);
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(0, status_check.nacks.size()); // Nothing else lost
// Write status PDU to RLC1
rlc1.write_pdu(status_buf.msg, status_buf.N_bytes);
// Check the Retx of SN=3 has been removed
TESTASSERT_EQ(0, rlc1.get_buffer_state());
TESTASSERT_EQ(0, rlc1_tx->get_retx_queue_size());
}
{
// Attempt to read from rlc1 to verify there nothing to read from it
byte_buffer_t retx_buf;
uint32_t len = rlc1.read_pdu(retx_buf.msg, data_pdu_size);
retx_buf.N_bytes = len;
TESTASSERT_EQ(0, len);
}
{
// rlc2 should not issue further status PDUs as time passes (even after expiry of t_status_prohibit)
int32_t checktime = 2 * rlc2_config.am_nr.t_status_prohibit;
for (int cnt = 0; cnt < checktime; cnt++) {
timers.step_all();
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)*data_pdu_size; // (NBUFS) * PDU size
uint32_t total_rx_pdu_bytes1 = 3 * status_pdu_ack_size + 1 * status_pdu_nack_size; // 3 status PDU (1 with a NACK)
uint32_t total_tx_pdu_bytes2 =
3 * status_pdu_ack_size + status_pdu_nack_size; // Three status PDU (one with a NACK, two without)
uint32_t total_rx_pdu_bytes2 = (NBUFS)*data_pdu_size; // (NBUFS - 1 Lost + 1 Late) * 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, metrics1.num_tx_pdus); // 5 transmissions, no re-transmission
TESTASSERT_EQ(3, metrics1.num_rx_pdus); // 3 status PDUs
TESTASSERT_EQ(total_tx_pdu_bytes1, metrics1.num_tx_pdu_bytes); // (NBUFS) * PDU size
TESTASSERT_EQ(total_rx_pdu_bytes1, metrics1.num_rx_pdu_bytes); // 3 status PDU (1 with a NACK)
TESTASSERT_EQ(0, metrics1.num_lost_sdus); // No lost SDUs
// SDU 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);
// PDU metrics
TESTASSERT_EQ(3, metrics2.num_tx_pdus); // 3 status PDUs
TESTASSERT_EQ(5, metrics2.num_rx_pdus); // 5 transmissions, no re-transmission
TESTASSERT_EQ(total_tx_pdu_bytes2, metrics2.num_tx_pdu_bytes); // Three status PDU (one with a NACK, two without)
TESTASSERT_EQ(total_rx_pdu_bytes2, metrics2.num_rx_pdu_bytes); // (NBUFS - 1 Lost + 1 Late) * 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(true, nullptr);
timer_handler timers(8);
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("basic segmentation ({} 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());
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;
}
// after configuring entity
TESTASSERT_EQ(0, rlc1.get_buffer_state());
// 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;
}
// This tests correct behaviour of the following flow:
// - Transmit 5 SDUs as whole PDUs
// - Loose 3rd PDU
// - Receive NACK for missing PDU
// - Retransmit lost PDU in 3 segments
// - Check metrics and state
int segment_retx_test(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 ");
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 ({} bit SN)", to_number(sn_size));
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 rlc_cnfg = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
rlc_cnfg.am_nr.t_poll_retx = -1;
if (not rlc1.configure(rlc_cnfg)) {
return -1;
}
if (not rlc2.configure(rlc_cnfg)) {
return -1;
}
// after configuring entity
TESTASSERT_EQ(0, rlc1.get_buffer_state());
// Push 5 SDUs into RLC1
unique_byte_buffer_t sdu_bufs[NBUFS];
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 (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 3 bytes
sdu_bufs[i]->md.pdcp_sn = i; // PDCP SN for notifications
rlc1.write_sdu(std::move(sdu_bufs[i]));
}
uint32_t expected_buffer_state = (header_size + payload_size) * NBUFS;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
// 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, header_size + payload_size);
pdu_bufs[i].N_bytes = len;
TESTASSERT_EQ(header_size + payload_size, 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(sn_size);
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;
int 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(sn_size);
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.nacks.size()); // 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(header_size + payload_size, rlc1.get_buffer_state());
}
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;
{
// 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, pdu_size_first);
TESTASSERT_EQ(pdu_size_first, len);
} else {
len = rlc1.read_pdu(retx_buf.msg, pdu_size_continued);
TESTASSERT_EQ(pdu_size_continued, 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, sn_size, &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();
uint32_t data_pdu_size = header_size + payload_size;
uint32_t total_tx_pdu_bytes1 = NBUFS * data_pdu_size + pdu_size_first + 2 * pdu_size_continued;
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;
uint32_t total_rx_pdu_bytes2 = (NBUFS - 1) * data_pdu_size + pdu_size_first + 2 * pdu_size_continued;
// 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(total_tx_pdu_bytes1, metrics1.num_tx_pdu_bytes);
TESTASSERT_EQ(total_rx_pdu_bytes1, metrics1.num_rx_pdu_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(7, metrics2.num_rx_pdus); // 7 PDUs (8 tx'ed, but one was lost)
TESTASSERT_EQ(total_tx_pdu_bytes2, metrics2.num_tx_pdu_bytes);
TESTASSERT_EQ(total_rx_pdu_bytes2,
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;
}
// This tests correct behaviour of the following flow:
// - Transmit 5 SDUs as whole PDUs
// - Loose 3rd PDU
// - Receive NACK for missing PDU
// - Retransmit lost PDU in 3 segments
// - Loose first and last segment
// - Receive NACKs for missing segments
// - Receive duplicate of previous NACKs
// - Retransmit missing segments again, but only once!
// - Check metrics and state
int segment_retx_and_loose_segments_test(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 ");
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 and loose some segments ({} bit SN)", to_number(sn_size));
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());
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;
}
// after configuring entity
TESTASSERT_EQ(0, rlc1.get_buffer_state());
// Push 5 SDUs into RLC1
unique_byte_buffer_t sdu_bufs[NBUFS];
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 (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 3 bytes
sdu_bufs[i]->md.pdcp_sn = i; // PDCP SN for notifications
rlc1.write_sdu(std::move(sdu_bufs[i]));
}
uint32_t expected_buffer_state = (header_size + payload_size) * NBUFS;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
// Read 5 PDUs from RLC1 (each with a full SDU)
for (int i = 0; i < NBUFS; i++) {
uint32_t len = rlc1.read_pdu(pdu_bufs[i].msg, header_size + payload_size);
pdu_bufs[i].N_bytes = len;
TESTASSERT_EQ(header_size + payload_size, len);
}
TESTASSERT_EQ(0, rlc1.get_buffer_state());
// Write 5 - 1 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(sn_size);
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;
int 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(sn_size);
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.nacks.size()); // 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(header_size + payload_size, rlc1.get_buffer_state());
}
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;
{
// 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, pdu_size_first);
TESTASSERT_EQ(pdu_size_first, len);
} else {
len = rlc1.read_pdu(retx_buf.msg, pdu_size_continued);
TESTASSERT_EQ(pdu_size_continued, 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, sn_size, &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);
}
// We loose the first and the last segment
if (i != 0 && i != 2) {
rlc2.write_pdu(retx_buf.msg, retx_buf.N_bytes);
}
}
TESTASSERT(0 == rlc1.get_buffer_state());
}
// Step timers until reassambly timeout expires
for (int cnt = 0; cnt < 35; cnt++) {
timers.step_all();
}
// t-reassembly has expired. There should be another NACK in the status report.
constexpr uint32_t status_pdu_so_size = 4;
TESTASSERT_EQ(status_pdu_ack_size + 2 * status_pdu_nack_size + 2 * status_pdu_so_size, rlc2.get_buffer_state());
{
// Read status PDU from RLC2
byte_buffer_t status_buf;
int len = rlc2.read_pdu(status_buf.msg, status_pdu_ack_size + 2 * status_pdu_nack_size + 2 * status_pdu_so_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(sn_size);
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(2, status_check.nacks.size()); // We lost two PDU segments.
TESTASSERT_EQ(3, status_check.nacks[0].nack_sn); // Lost PDU SN=3.
TESTASSERT_EQ(true, status_check.nacks[0].has_so); // This is a segment missing.
TESTASSERT_EQ(0, status_check.nacks[0].so_start); // Segment offset should be 0 here
TESTASSERT_EQ(0, status_check.nacks[0].so_end); // Segment end should be 0 here
TESTASSERT_EQ(true, status_check.nacks[1].has_so); // This is a segment missing.
TESTASSERT_EQ(2, status_check.nacks[1].so_start); // Segment offset should be 2 here
TESTASSERT_EQ(0xFFFF, status_check.nacks[1].so_end); // Segment end should be 0xFFFF here
// Write status PDU to RLC1
rlc1.write_pdu(status_buf.msg, status_buf.N_bytes);
// Write status PDU duplicate to RLC1
rlc1.write_pdu(status_buf.msg, status_buf.N_bytes);
// Check there are two Retx segments (a first one and a continued one)
TESTASSERT_EQ(pdu_size_first + pdu_size_continued, rlc1.get_buffer_state());
}
{
// Re-transmit the lost 2 segments
for (int i = 0; i < 2; i++) {
byte_buffer_t retx_buf;
uint32_t len = 0;
if (i == 0) {
len = rlc1.read_pdu(retx_buf.msg, pdu_size_first);
TESTASSERT_EQ(pdu_size_first, len);
} else {
len = rlc1.read_pdu(retx_buf.msg, pdu_size_continued);
TESTASSERT_EQ(pdu_size_continued, 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, sn_size, &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 {
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();
uint32_t data_pdu_size = header_size + payload_size;
uint32_t total_tx_pdu_bytes1 = NBUFS * data_pdu_size + 2 * pdu_size_first + 3 * pdu_size_continued;
uint32_t total_rx_pdu_bytes1 = status_pdu_ack_size + // ACK, no NACK
(status_pdu_ack_size + status_pdu_nack_size) + // ACK + NACK full SDU
2 * (status_pdu_ack_size + 2 * status_pdu_nack_size + // 2 * (ACK + NACK two segments)
2 * status_pdu_so_size);
uint32_t total_tx_pdu_bytes2 = status_pdu_ack_size + // ACK, no NACK
(status_pdu_ack_size + status_pdu_nack_size) + // ACK + NACK full SDU
1 * (status_pdu_ack_size + 2 * status_pdu_nack_size + // 1 * (ACK + NACK two segments)
2 * status_pdu_so_size);
uint32_t total_rx_pdu_bytes2 = (NBUFS - 1) * data_pdu_size + pdu_size_first + 2 * pdu_size_continued;
// 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 + 2, metrics1.num_tx_pdus); // 5 + (3 + 2) re-transmissions
TESTASSERT_EQ(4, metrics1.num_rx_pdus); // 4 status PDU
TESTASSERT_EQ(total_tx_pdu_bytes1, metrics1.num_tx_pdu_bytes);
TESTASSERT_EQ(total_rx_pdu_bytes1, metrics1.num_rx_pdu_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(3, metrics2.num_tx_pdus); // 3 status PDUs
TESTASSERT_EQ(7, metrics2.num_rx_pdus); // 7 PDUs (10 tx'ed, but 3 were lost)
TESTASSERT_EQ(total_tx_pdu_bytes2, metrics2.num_tx_pdu_bytes);
TESTASSERT_EQ(total_rx_pdu_bytes2,
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_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
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);
std::string str = "retx segment PDU (" + std::to_string(to_number(sn_size)) + " bit SN)";
test_delimit_logger delimiter(str.c_str());
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 rlc_cnfg = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
rlc_cnfg.am_nr.t_poll_retx = -1;
if (not rlc1.configure(rlc_cnfg)) {
return -1;
}
if (not rlc2.configure(rlc_cnfg)) {
return -1;
}
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
int n_sdu_bufs = 5;
int n_pdu_bufs = 15;
// Push 5 SDUs into RLC1
std::vector<unique_byte_buffer_t> sdu_bufs(n_sdu_bufs);
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 (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 = payload_size; // 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]));
}
uint32_t expected_buffer_state = (header_size + payload_size) * n_sdu_bufs;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
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;
// Read 15 PDUs from RLC1
std::vector<unique_byte_buffer_t> pdu_bufs(n_pdu_bufs);
for (int i = 0; i < n_pdu_bufs; i++) {
// First also test buffer state
uint32_t remaining_total_bytes = (payload_size * n_sdu_bufs) - (i * segment_size);
uint32_t remaining_full_sdus = remaining_total_bytes / payload_size;
uint32_t remaining_seg_bytes = remaining_total_bytes % payload_size;
uint32_t buffer_state_full_sdus = (header_size + payload_size) * remaining_full_sdus;
uint32_t buffer_state_seg_sdu = remaining_seg_bytes == 0 ? 0 : (header_size + so_size + remaining_seg_bytes);
expected_buffer_state = buffer_state_full_sdus + buffer_state_seg_sdu;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
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, pdu_size_first); // 2 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_first, len);
} else {
// Middle or last segment, SO present
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_continued); // 4 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_continued, 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) {
// Lose first segment of RLC_SN=1.
// Lose middle segment of RLC_SN=2.
// Lose last segment of RLC_SN=3.
rlc2.write_pdu(pdu_bufs[i]->msg, pdu_bufs[i]->N_bytes);
}
}
{
// Double check rx state
rlc_am_nr_rx_state_t st = rx2->get_rx_state();
TESTASSERT_EQ(1, st.rx_next);
TESTASSERT_EQ(1, st.rx_highest_status);
TESTASSERT_EQ(2, st.rx_next_status_trigger); // Rx_Next_Highest + 1, when the t-Reordering was started
TESTASSERT_EQ(5, st.rx_next_highest); // Highest SN received + 1
}
// Only after t-reassembly has expired, will the status report include NACKs.
// RX_Highest_Status will be updated to to the SN
// of the first RLC SDU with SN >= RX_Next_Status_Trigger
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(sn_size);
rlc_am_nr_read_status_pdu(&status_buf, sn_size, &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();
}
// After the t-Reassembly expires:
// - RX_Highest_Status is updated to the SN of the first RLC SDU with SN >= RX_Next_Status_Trigger, i.e., SN=2
// - Because RX_Next_Highest> RX_Highest_Status +1:
// - t-Reassembly is restarted, and
// - RX_Next_Status_Trigger is set to RX_Next_Highest.
{
// Double check rx state
rlc_am_nr_rx_state_t st = rx2->get_rx_state();
TESTASSERT_EQ(1, st.rx_next);
TESTASSERT_EQ(2, st.rx_highest_status);
TESTASSERT_EQ(5, st.rx_next_status_trigger); // Rx_Next_Highest + 1, when the t-Reassembly was started
TESTASSERT_EQ(5, st.rx_next_highest); // Highest SN received + 1
}
// t-reassembly has expired. Becuse RX_Highest_Status is 2
// There should be an ACK of SN=2 and a NACK of SN=1
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;
constexpr uint32_t status_pdu_so_size = 4;
TESTASSERT_EQ(status_pdu_ack_size + status_pdu_nack_size + status_pdu_so_size,
rlc2.get_buffer_state()); // 3 bytes for fixed header (ACK+E1) + 6 for NACK with SO = 9.
{
// Read status PDU from RLC2
byte_buffer_t status_buf;
int len = rlc2.read_pdu(status_buf.msg, status_pdu_ack_size + status_pdu_nack_size + status_pdu_so_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(sn_size);
rlc_am_nr_read_status_pdu(&status_buf, sn_size, &status_check);
TESTASSERT_EQ(2, status_check.ack_sn); // 5 is the next expected SN.
TESTASSERT_EQ(1, status_check.nacks.size()); // 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); // It's a segment.
TESTASSERT_EQ(0, status_check.nacks[0].so_start); // First byte missing is 0.
TESTASSERT_EQ(0, status_check.nacks[0].so_end); // Last byte of the segment.
}
// Step timers until reassambly timeout expires
for (int cnt = 0; cnt < 35; cnt++) {
timers.step_all();
}
// After the t-Reassembly expires:
// - RX_Highest_Status is updated to the SN of the first RLC SDU with SN >= RX_Next_Status_Trigger, i.e., SN=2
// - Because RX_Next_Highest> RX_Highest_Status +1:
// - t-Reassembly is restarted, and
// - RX_Next_Status_Trigger is set to RX_Next_Highest.
{
// Double check rx state
rlc_am_nr_rx_state_t st = rx2->get_rx_state();
TESTASSERT_EQ(1, st.rx_next);
TESTASSERT_EQ(5, st.rx_highest_status);
TESTASSERT_EQ(5, st.rx_next_status_trigger); // Rx_Next_Highest + 1, when the t-Reordering was started
TESTASSERT_EQ(5, st.rx_next_highest); // Highest SN received + 1
}
// 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(status_pdu_ack_size + 3 * (status_pdu_nack_size + status_pdu_so_size), rlc2.get_buffer_state());
{
// Read status PDU from RLC2
byte_buffer_t status_buf;
int len = rlc2.read_pdu(status_buf.msg, status_pdu_ack_size + 3 * (status_pdu_nack_size + status_pdu_so_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(sn_size);
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(3, status_check.nacks.size()); // 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 are 3 Retx segments (a first one and two continued ones)
TESTASSERT_EQ(pdu_size_first + 2 * pdu_size_continued, rlc1.get_buffer_state());
}
{
// Re-transmit the 3 lost segments
for (int i = 0; i < 3; i++) {
// First also test buffer state
uint32_t remaining_segments = 3 - i;
expected_buffer_state = remaining_segments * (header_size + so_size + segment_size);
if (i == 0) { // subtract so_size, because in this setup the first retx is a "first_segment" without SO.
expected_buffer_state -= so_size;
}
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
byte_buffer_t retx_buf;
uint32_t len = 0;
if (i == 0) {
len = rlc1.read_pdu(retx_buf.msg, pdu_size_first);
TESTASSERT_EQ(pdu_size_first, len);
} else {
len = rlc1.read_pdu(retx_buf.msg, pdu_size_continued);
TESTASSERT_EQ(pdu_size_continued, 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, sn_size, &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();
uint32_t data_pdu_size = header_size + payload_size;
uint32_t total_tx_pdu_bytes1 = 5 * pdu_size_first + 10 * pdu_size_continued + pdu_size_first + 2 * pdu_size_continued;
uint32_t total_rx_pdu_bytes1 = 2 * status_pdu_ack_size + 3 * (status_pdu_nack_size + status_pdu_so_size);
uint32_t total_tx_pdu_bytes2 = 3 * status_pdu_ack_size + 4 * (status_pdu_nack_size + status_pdu_so_size);
uint32_t total_rx_pdu_bytes2 = 4 * pdu_size_first + 8 * pdu_size_continued + pdu_size_first + 2 * pdu_size_continued;
// 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(total_tx_pdu_bytes1,
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(total_rx_pdu_bytes1,
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) = 24
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(3, metrics2.num_tx_pdus); // 3 status PDUs
TESTASSERT_EQ(15, metrics2.num_rx_pdus); // 15 PDUs (18 tx'ed, but three were lost)
TESTASSERT_EQ(total_tx_pdu_bytes2, // Three status PDU. One with just an ack
metrics2.num_tx_pdu_bytes); // Another with 1 NACK with SO.
// Another with 3 NACKs all with SO.
TESTASSERT_EQ(total_rx_pdu_bytes2, // 3 Bytes (header + data size, without SO) * 5 (N PDUs without SO)
metrics2.num_rx_pdu_bytes); // 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;
}
// We only increment TX_NEXT after transmitting the last segment of a SDU
// This means that we need to handle status reports where ACK_SN may be larger
// than TX_NEXT, as it may contain a NACK for the partially transmitted PDU with
// SN==TX_NEXT.
int handle_status_of_non_tx_last_segment(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
timer_handler timers(8);
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("basic segmentation ({} 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());
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;
}
// after configuring entity
TESTASSERT_EQ(0, rlc1.get_buffer_state());
// 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 2 PDUs. Leave last one in the tx_window.
constexpr uint16_t n_pdus = 2;
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);
}
}
// Only middle PDU into RLC2
// First PDU is lost to trigger status report
for (int i = 0; i < n_pdus; i++) {
if (i == 1) {
rlc2.write_pdu(pdu_bufs[i]->msg, pdu_bufs[i]->N_bytes);
}
}
// Advance timer to trigger status report
for (uint8_t t = 0; t < 35; t++) {
timers.step_all();
}
TESTASSERT_NEQ(0, rlc2.get_buffer_state());
// Make sure RLC 1 has only the last segment to TX before getting the status report
TESTASSERT_EQ(pdu_size_continued, rlc1.get_buffer_state());
// Get status report from RLC 2
// and write it to RLC 1
{
unique_byte_buffer_t status_buf = srsran::make_byte_buffer();
status_buf->N_bytes = rlc2.read_pdu(status_buf->msg, 100);
rlc1.write_pdu(status_buf->msg, status_buf->N_bytes);
}
// Make sure RLC 1 now has the last segment to TX and the RETX of the first segment
TESTASSERT_EQ(pdu_size_continued + pdu_size_first, rlc1.get_buffer_state());
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_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
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 ({} bit SN)", to_number(sn_size));
const rlc_config_t rlc_cfg = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
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];
constexpr uint32_t payload_size = 1; // Give each buffer a size of 1 byte
uint32_t header_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3;
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 = payload_size; // 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]));
}
uint32_t pdu_size = header_size + payload_size;
// 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, pdu_size); // 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(sn_size);
fake_status.ack_sn = 2; // delivered up to SN=1
rlc_status_nack_t nack; // one SN was lost
nack.nack_sn = 0; // it was SN=0 that was lost
fake_status.push_nack(nack);
// 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, pdu_size); // 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_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
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 ({} bit SN)", to_number(sn_size));
const rlc_config_t rlc_cfg = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
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];
constexpr uint32_t payload_size = 20; // Give each buffer a size of 20 bytes
uint32_t header_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3;
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 = payload_size; // 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]));
}
constexpr uint32_t so_size = 2;
constexpr uint32_t segment_size_first = 13;
constexpr uint32_t segment_size_continued = 7;
uint32_t pdu_size_first = header_size + segment_size_first;
uint32_t pdu_size_continued = header_size + so_size + segment_size_continued;
// 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, pdu_size_first);
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(sn_size);
status_lost_both_segments.ack_sn = 2; // delivered up to SN=1
// two segments lost
{
rlc_status_nack_t nack;
nack.nack_sn = 0; // it was SN=0 that was lost
nack.has_so = true; // this NACKs a segment
nack.so_start = 0; // segment starts at (and includes) byte 0
nack.so_end = 12; // segment ends at (and includes) byte 12
status_lost_both_segments.push_nack(nack);
}
{
rlc_status_nack_t nack;
nack.nack_sn = 0; // it was SN=0 that was lost
nack.has_so = true; // this NACKs a segment
nack.so_start = 13; // segment starts at (and includes) byte 13
nack.so_end = 19; // segment ends at (and includes) byte 19
status_lost_both_segments.push_nack(nack);
}
// 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 1}
rlc_am_nr_status_pdu_t status_lost_second_segment(sn_size);
status_lost_second_segment.ack_sn = 2; // delivered up to SN=1
// one SN was lost
{
rlc_status_nack_t nack;
nack.nack_sn = 0; // it was SN=0 that was lost
nack.has_so = true; // this NACKs a segment
nack.so_start = 13; // segment starts at (and includes) byte 13
nack.so_end = 19; // segment ends at (and includes) byte 19
status_lost_second_segment.push_nack(nack);
}
// 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, pdu_size_first); // 2 byte header + 13 byte payload
len = rlc1.read_pdu(pdu_buf.msg, pdu_size_first); // 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, pdu_size_first); // 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_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
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("discard test ({} bit SN)", to_number(sn_size));
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(to_number(sn_size)))) {
return SRSRAN_ERROR;
}
if (not rlc2.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) {
return SRSRAN_ERROR;
}
uint32_t num_tx_sdus = 1;
uint32_t header_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3;
uint32_t payload_size = 5; // Give each buffer a size of 5 bytes
// Test discarding the single SDU from the queue
{
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 = payload_size;
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);
num_tx_sdus = 10;
payload_size = 7; // Give each buffer a size of 7 bytes
// Test discarding two SDUs in the middle (SN=3) and end (SN=9) of the queue and read PDUs after
{
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 = payload_size;
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() == num_tx_sdus * (header_size + payload_size)); // 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() == (num_tx_sdus - 1) * (header_size + payload_size));
rlc1.discard_sdu(9); // Try to discard PDCP_SN=9
TESTASSERT(rlc1.has_data() == true);
TESTASSERT(rlc1.get_buffer_state() == (num_tx_sdus - 2) * (header_size + payload_size));
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((header_size + payload_size) == 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(), sn_size, &header);
TESTASSERT(header.sn == i);
}
}
TESTASSERT(rlc1.has_data() == false);
srslog::fetch_basic_logger("TEST").info("Received %zd SDUs", tester.sdus.size());
num_tx_sdus = 3;
payload_size = 7; // Give each buffer a size of 7 bytes
// Test discarding non-existing SDU from the queue
{
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 = payload_size;
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() == num_tx_sdus * (header_size + payload_size)); // 3 * (2B Header + 7B Payload)
rlc1.discard_sdu(8); // Try to discard PDCP_SN=8, which doesn't exist
TESTASSERT(rlc1.get_buffer_state() == num_tx_sdus * (header_size + payload_size)); // 3 * (2B Header + 7B Payload)
return SRSRAN_SUCCESS;
}
// Test p bit set on new TX with PollPDU
int poll_pdu(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
timer_handler timers(8);
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("pollPDU test ({} bit SN)", to_number(sn_size));
srslog::fetch_basic_logger("RLC_AM_1").set_hex_dump_max_size(100);
rlc_config_t rlc_cnfg = {};
rlc_cnfg.rat = srsran_rat_t::nr;
rlc_cnfg.rlc_mode = rlc_mode_t::am;
rlc_cnfg.am_nr.tx_sn_field_length = sn_size; // Number of bits used for tx (UL) sequence number
rlc_cnfg.am_nr.rx_sn_field_length = sn_size; // Number of bits used for rx (DL) sequence number
rlc_cnfg.am_nr.poll_pdu = 4;
rlc_cnfg.am_nr.poll_byte = 3000;
rlc_cnfg.am_nr.t_status_prohibit = 8;
rlc_cnfg.am_nr.max_retx_thresh = 8;
rlc_cnfg.am_nr.t_reassembly = 35;
// Test p bit set on new TX with PollPDU
{
rlc_am rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers);
if (not rlc1.configure(rlc_cnfg)) {
return SRSRAN_ERROR;
}
// pollPDU == 4
uint32_t num_tx_sdus = 6;
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 = 1;
sdu->md.pdcp_sn = i;
rlc1.write_sdu(std::move(sdu));
}
uint32_t num_tx_pdus = 6;
uint32_t pdu_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 3 : 4;
for (uint32_t i = 0; i < num_tx_pdus; ++i) {
unique_byte_buffer_t pdu = srsran::make_byte_buffer();
TESTASSERT(pdu != nullptr);
pdu->N_bytes = rlc1.read_pdu(pdu->msg, pdu_size);
rlc_am_nr_pdu_header_t hdr;
rlc_am_nr_read_data_pdu_header(pdu.get(), sn_size, &hdr);
if (i != 3 && i != 5) { // P bit set for PollPDU and for empty TX queue
TESTASSERT_EQ(0, hdr.p);
} else {
TESTASSERT_EQ(1, hdr.p);
}
}
}
return SRSRAN_SUCCESS;
}
// Test p bit set on new TX with PollBYTE
int poll_byte(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
timer_handler timers(8);
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("pollBYTE test ({} bit SN)", to_number(sn_size));
srslog::fetch_basic_logger("RLC_AM_1").set_hex_dump_max_size(100);
rlc_config_t rlc_cnfg = {};
rlc_cnfg.rat = srsran_rat_t::nr;
rlc_cnfg.rlc_mode = rlc_mode_t::am;
rlc_cnfg.am_nr.tx_sn_field_length = sn_size; // Number of bits used for tx (UL) sequence number
rlc_cnfg.am_nr.rx_sn_field_length = sn_size; // Number of bits used for rx (DL) sequence number
rlc_cnfg.am_nr.poll_pdu = 4;
rlc_cnfg.am_nr.poll_byte = 3000;
rlc_cnfg.am_nr.t_status_prohibit = 8;
rlc_cnfg.am_nr.max_retx_thresh = 8;
rlc_cnfg.am_nr.t_reassembly = 35;
rlc_am rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers);
if (not rlc1.configure(rlc_cnfg)) {
return SRSRAN_ERROR;
}
// pollByte == 3000
uint32_t num_tx_sdus = 4;
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 = i == 0 ? 2999 : 1;
sdu->md.pdcp_sn = i;
rlc1.write_sdu(std::move(sdu));
}
uint32_t num_tx_pdus = num_tx_sdus;
uint32_t small_pdu_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 3 : 4;
uint32_t large_pdu_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 3001 : 3002;
for (uint32_t i = 0; i < num_tx_pdus; ++i) {
unique_byte_buffer_t pdu = srsran::make_byte_buffer();
TESTASSERT(pdu != nullptr);
uint32_t nof_bytes = i == 0 ? large_pdu_size : small_pdu_size;
pdu->N_bytes = rlc1.read_pdu(pdu->msg, nof_bytes);
TESTASSERT_EQ(nof_bytes, pdu->N_bytes);
rlc_am_nr_pdu_header_t hdr;
rlc_am_nr_read_data_pdu_header(pdu.get(), rlc_am_nr_sn_size_t::size18bits, &hdr);
if (i != 1 && i != 3) {
TESTASSERT_EQ(0, hdr.p);
} else {
TESTASSERT_EQ(1, hdr.p);
}
}
return SRSRAN_SUCCESS;
}
// Test p bit set on RETXes that cause an empty retx queue.
int poll_retx(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
timer_handler timers(8);
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("poll retx test ({} bit SN)", to_number(sn_size));
srslog::fetch_basic_logger("RLC_AM_1").set_hex_dump_max_size(100);
rlc_config_t rlc_cnfg = {};
rlc_cnfg.rat = srsran_rat_t::nr;
rlc_cnfg.rlc_mode = rlc_mode_t::am;
rlc_cnfg.am_nr.tx_sn_field_length = sn_size; // Number of bits used for tx (UL) sequence number
rlc_cnfg.am_nr.rx_sn_field_length = sn_size; // Number of bits used for rx (DL) sequence number
rlc_cnfg.am_nr.poll_pdu = 4;
rlc_cnfg.am_nr.poll_byte = 3000;
rlc_cnfg.am_nr.t_status_prohibit = 8;
rlc_cnfg.am_nr.max_retx_thresh = 8;
rlc_cnfg.am_nr.t_reassembly = 35;
rlc_am rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers);
if (not rlc1.configure(rlc_cnfg)) {
return SRSRAN_ERROR;
}
// pollPDU == 4
{
uint32_t num_tx_sdus = 5;
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 = 1;
sdu->md.pdcp_sn = i;
rlc1.write_sdu(std::move(sdu));
}
}
{
// Read 3 PDUs and NACK the second one
uint32_t num_tx_pdus = 3;
uint32_t pdu_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 3 : 4;
for (uint32_t i = 0; i < num_tx_pdus; ++i) {
unique_byte_buffer_t pdu = srsran::make_byte_buffer();
TESTASSERT(pdu != nullptr);
pdu->N_bytes = rlc1.read_pdu(pdu->msg, pdu_size);
rlc_am_nr_pdu_header_t hdr;
rlc_am_nr_read_data_pdu_header(pdu.get(), sn_size, &hdr);
TESTASSERT_EQ(0, hdr.p);
}
}
{
unique_byte_buffer_t status_pdu = srsran::make_byte_buffer();
TESTASSERT(status_pdu != nullptr);
rlc_am_nr_status_pdu_t status(rlc_am_nr_sn_size_t::size12bits);
status.ack_sn = 2;
{
rlc_status_nack_t nack;
nack.nack_sn = 1; // SN=1 needs RETX
status.push_nack(nack);
}
rlc_am_nr_write_status_pdu(status, rlc_cnfg.am_nr.tx_sn_field_length, status_pdu.get());
rlc1.write_pdu(status_pdu->msg, status_pdu->N_bytes);
}
{
// Read 2 PDUs,
uint32_t num_tx_pdus = 3;
uint32_t pdu_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 3 : 4;
for (uint32_t i = 0; i < num_tx_pdus; ++i) {
unique_byte_buffer_t pdu = srsran::make_byte_buffer();
TESTASSERT(pdu != nullptr);
pdu->N_bytes = rlc1.read_pdu(pdu->msg, pdu_size);
TESTASSERT_EQ(pdu_size, pdu->N_bytes);
rlc_am_nr_pdu_header_t hdr;
rlc_am_nr_read_data_pdu_header(pdu.get(), sn_size, &hdr);
if (i == 0) {
TESTASSERT_EQ(0, hdr.p); // No poll since pollPDU is not incremented for RETX
TESTASSERT_EQ(1, hdr.sn);
} else {
TESTASSERT_EQ(1, hdr.p); // poll set because of pollPDU for SN=3 and empty buffer on SN=4
}
}
}
{
unique_byte_buffer_t status_pdu = srsran::make_byte_buffer();
TESTASSERT(status_pdu != nullptr);
rlc_am_nr_status_pdu_t status(rlc_am_nr_sn_size_t::size12bits);
status.ack_sn = 4;
{
rlc_status_nack_t nack;
nack.nack_sn = 1; // SN=1 needs RETX
status.push_nack(nack);
}
rlc_am_nr_write_status_pdu(status, rlc_cnfg.am_nr.tx_sn_field_length, status_pdu.get());
rlc1.write_pdu(status_pdu->msg, status_pdu->N_bytes);
}
{
// Read 1 RETX PDU. Empty retx buffer, so poll should be set
uint32_t num_tx_pdus = 1;
uint32_t pdu_size = sn_size == rlc_am_nr_sn_size_t::size12bits ? 3 : 4;
for (uint32_t i = 0; i < num_tx_pdus; ++i) {
unique_byte_buffer_t pdu = srsran::make_byte_buffer();
TESTASSERT(pdu != nullptr);
pdu->N_bytes = rlc1.read_pdu(pdu->msg, pdu_size);
TESTASSERT_EQ(pdu_size, pdu->N_bytes);
rlc_am_nr_pdu_header_t hdr;
rlc_am_nr_read_data_pdu_header(pdu.get(), sn_size, &hdr);
if (i == 0) {
TESTASSERT_EQ(1, hdr.p); // Poll set because of empty retx buffer
TESTASSERT_EQ(1, hdr.sn);
}
}
}
return SRSRAN_SUCCESS;
}
// This test checks whether re-transmissions are triggered correctly in case the t-PollRetranmission expires.
// It checks if the poll retx timer is re-armed upon receiving an ACK for POLL_SN
bool poll_retx_expiry(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
timer_handler timers(8);
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("poll retx expiry test ({} bit SN)", to_number(sn_size));
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);
rlc_config_t rlc_cnfg = rlc_config_t::default_rlc_am_nr_config();
rlc_cnfg.am_nr.tx_sn_field_length = sn_size; // Number of bits used for tx (UL) sequence number
rlc_cnfg.am_nr.rx_sn_field_length = sn_size; // Number of bits used for rx (DL) sequence number
rlc_cnfg.am_nr.t_poll_retx = 65;
rlc_cnfg.am_nr.poll_pdu = -1;
rlc_cnfg.am_nr.poll_byte = -1;
rlc_cnfg.am_nr.max_retx_thresh = 6;
rlc_cnfg.am_nr.t_status_prohibit = 55;
rlc_am rlc1(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_1"), 1, &tester, &tester, &timers);
if (not rlc1.configure(rlc_cnfg)) {
return SRSRAN_ERROR;
}
rlc_am rlc2(srsran_rat_t::nr, srslog::fetch_basic_logger("RLC_AM_2"), 1, &tester, &tester, &timers);
if (not rlc2.configure(rlc_cnfg)) {
return SRSRAN_ERROR;
}
unsigned hdr_no_so = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3;
unsigned hdr_with_so = sn_size == rlc_am_nr_sn_size_t::size12bits ? 4 : 5;
unsigned ack_size = 3;
unsigned nack_size_no_so = sn_size == rlc_am_nr_sn_size_t::size12bits ? 2 : 3;
unsigned nack_size_with_so = sn_size == rlc_am_nr_sn_size_t::size12bits ? (2 + 4) : (3 + 4);
// Tx SDU with 135 B of data
// Read it in two PDU segments, so=0 (89B of data)
// and so=89 (46B of data)
{
// TX a single SDU
unique_byte_buffer_t sdu = srsran::make_byte_buffer();
TESTASSERT(sdu != nullptr);
sdu->N_bytes = 135;
for (uint32_t k = 0; k < sdu->N_bytes; ++k) {
sdu->msg[k] = 0; // Write the index into the buffer
}
sdu->md.pdcp_sn = 0;
rlc1.write_sdu(std::move(sdu));
// Read two PDUs. The last PDU should trigger polling, as it
// is the last SDU segment in the buffer.
uint32_t pdu1_size = 89 + hdr_no_so;
unique_byte_buffer_t pdu1 = srsran::make_byte_buffer();
TESTASSERT(pdu1 != nullptr);
pdu1->N_bytes = rlc1.read_pdu(pdu1->msg, pdu1_size); // 89 bytes payload
uint32_t pdu2_size = 46 + hdr_with_so;
unique_byte_buffer_t pdu2 = srsran::make_byte_buffer();
TESTASSERT(pdu2 != nullptr);
pdu2->N_bytes = rlc1.read_pdu(pdu2->msg, pdu2_size); // 46 bytes payload
// Deliver PDU2 to RLC2. PDU1 is lost
rlc2.write_pdu(pdu2->msg, pdu2->N_bytes);
// Double-check polling status in PDUs
rlc_am_nr_pdu_header_t hdr1 = {};
rlc_am_nr_read_data_pdu_header(pdu1.get(), sn_size, &hdr1);
rlc_am_nr_pdu_header_t hdr2 = {};
rlc_am_nr_read_data_pdu_header(pdu2.get(), sn_size, &hdr2);
TESTASSERT_EQ(0, hdr1.p);
TESTASSERT_EQ(1, hdr2.p);
}
// Step timers until t-PollRetransmit timer expires on RLC1
// t-PollRetransmit will schedule SN=0, so=0, payload_len=89 for RETX
// t-Reordering timer also will expire on RLC2, meaning we will also get a status report.
TESTASSERT_EQ(false, rlc1.has_data());
for (int cnt = 0; cnt < 65; cnt++) {
timers.step_all();
}
// Make sure that the SDU segment was scheduled for RETX
TESTASSERT_EQ(89 + hdr_no_so, rlc1.get_buffer_state());
// Further segment RETX segment
// First SDU segment (81B of data)
{
unique_byte_buffer_t pdu = srsran::make_byte_buffer();
TESTASSERT(pdu != nullptr);
pdu->N_bytes = rlc1.read_pdu(pdu->msg, 81 + hdr_no_so);
}
// Second SDU segment (8B of data)
{
unique_byte_buffer_t pdu = srsran::make_byte_buffer();
TESTASSERT(pdu != nullptr);
pdu->N_bytes = rlc1.read_pdu(pdu->msg, 8 + hdr_with_so);
}
TESTASSERT_EQ(0, rlc1.get_buffer_state());
// Read status PDU from RLC2 (triggered previously from t-Reordering)
// ACK=1, NACKs=1
// NACK_SN[0].sn=0, NACK_SN[0].so_start=0, NACK_SN[0].so_end=89
uint32_t status_size = rlc2.get_buffer_state();
TESTASSERT_EQ(ack_size + nack_size_with_so, status_size);
// Read status PDU from RLC2
unique_byte_buffer_t status_buf = srsran::make_byte_buffer();
TESTASSERT(status_buf != nullptr);
int len = rlc2.read_pdu(status_buf->msg, status_size);
status_buf->N_bytes = len;
TESTASSERT(0 == rlc2.get_buffer_state());
// Assert status is correct
rlc_am_nr_status_pdu_t status_check(sn_size);
rlc_am_nr_read_status_pdu(status_buf.get(), sn_size, &status_check);
TESTASSERT(status_check.ack_sn == 1); // SN=1 is first SN missing without a NACK
TESTASSERT(status_check.nacks.size() == 1); // 1 PDU lost
TESTASSERT(status_check.nacks[0].nack_sn == 0); // SN=0
TESTASSERT(status_check.nacks[0].so_start == 0); // SN=0
TESTASSERT_EQ(88, status_check.nacks[0].so_end); // SN=0
TESTASSERT_EQ(0, rlc1.get_buffer_state());
// Deliver status PDU after ReTX to RLC1. This should restart t-PollRetransmission
// It NACKs SDU segment 0:81 and 81:89
TESTASSERT_EQ(false, rlc1.has_data());
rlc1.write_pdu(status_buf->msg, status_buf->N_bytes);
TESTASSERT_EQ(true, rlc1.has_data());
// [I] SRB1 Retx SDU segment (81 B of data)
// [I] SRB1 Retx PDU segment (8 B of data)
{
unique_byte_buffer_t pdu1 = srsran::make_byte_buffer();
TESTASSERT(pdu1 != nullptr);
pdu1->N_bytes = rlc1.read_pdu(pdu1->msg, 81 + hdr_no_so);
unique_byte_buffer_t pdu2 = srsran::make_byte_buffer();
TESTASSERT(pdu2 != nullptr);
pdu2->N_bytes = rlc1.read_pdu(pdu2->msg, 8 + hdr_with_so);
}
TESTASSERT_EQ(false, rlc1.has_data()); // We don't have any more data
// Step timers until t-PollRetransmission timer expires on RLC1
// [I] SRB1 Schedule SN=3 for reTx
for (int cnt = 0; cnt < 66; cnt++) {
timers.step_all();
}
TESTASSERT_EQ(81 + hdr_no_so, rlc1.get_buffer_state());
srslog::fetch_basic_logger("TEST").info("t-PollRetransmssion successfully restarted.");
return SRSRAN_SUCCESS;
}
int rx_nack_range_no_so_test(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
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);
std::string str = "Rx NACK range test (" + std::to_string(to_number(sn_size)) + " bit SN)";
test_delimit_logger delimiter(str.c_str());
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 rlc_cnfg = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
rlc_cnfg.am_nr.t_poll_retx = -1;
if (not rlc1.configure(rlc_cnfg)) {
return -1;
}
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
int n_sdu_bufs = 5;
int n_pdu_bufs = 15;
// Push 5 SDUs into RLC1
std::vector<unique_byte_buffer_t> sdu_bufs(n_sdu_bufs);
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 (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 = payload_size; // 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]));
}
uint32_t expected_buffer_state = (header_size + payload_size) * n_sdu_bufs;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
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;
// Read 15 PDUs from RLC1
std::vector<unique_byte_buffer_t> pdu_bufs(n_pdu_bufs);
for (int i = 0; i < n_pdu_bufs; i++) {
// First also test buffer state
uint32_t remaining_total_bytes = (payload_size * n_sdu_bufs) - (i * segment_size);
uint32_t remaining_full_sdus = remaining_total_bytes / payload_size;
uint32_t remaining_seg_bytes = remaining_total_bytes % payload_size;
uint32_t buffer_state_full_sdus = (header_size + payload_size) * remaining_full_sdus;
uint32_t buffer_state_seg_sdu = remaining_seg_bytes == 0 ? 0 : (header_size + so_size + remaining_seg_bytes);
expected_buffer_state = buffer_state_full_sdus + buffer_state_seg_sdu;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
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, pdu_size_first); // 2 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_first, len);
} else {
// Middle or last segment, SO present
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_continued); // 4 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_continued, len);
}
}
// Deliver dummy status report with nack range betwen PDU 6 and 10.
rlc_am_nr_status_pdu_t status(sn_size);
status.ack_sn = 5;
rlc_status_nack_t nack = {};
nack.nack_sn = 1;
nack.has_nack_range = true;
nack.nack_range = 3;
status.push_nack(nack);
byte_buffer_t status_pdu;
rlc_am_nr_write_status_pdu(status, sn_size, &status_pdu);
rlc1.write_pdu(status_pdu.msg, status_pdu.N_bytes);
TESTASSERT_EQ(3 * pdu_size_first + 6 * pdu_size_continued, rlc1.get_buffer_state());
return SRSRAN_SUCCESS;
}
int rx_nack_range_with_so_test(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
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);
std::string str = "Rx NACK range test (" + std::to_string(to_number(sn_size)) + " bit SN)";
test_delimit_logger delimiter(str.c_str());
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 rlc_cnfg = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
rlc_cnfg.am_nr.t_poll_retx = -1;
if (not rlc1.configure(rlc_cnfg)) {
return -1;
}
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
int n_sdu_bufs = 5;
int n_pdu_bufs = 15;
// Push 5 SDUs into RLC1
std::vector<unique_byte_buffer_t> sdu_bufs(n_sdu_bufs);
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 (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 = payload_size; // 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]));
}
uint32_t expected_buffer_state = (header_size + payload_size) * n_sdu_bufs;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
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;
// Read 15 PDUs from RLC1
std::vector<unique_byte_buffer_t> pdu_bufs(n_pdu_bufs);
for (int i = 0; i < n_pdu_bufs; i++) {
// First also test buffer state
uint32_t remaining_total_bytes = (payload_size * n_sdu_bufs) - (i * segment_size);
uint32_t remaining_full_sdus = remaining_total_bytes / payload_size;
uint32_t remaining_seg_bytes = remaining_total_bytes % payload_size;
uint32_t buffer_state_full_sdus = (header_size + payload_size) * remaining_full_sdus;
uint32_t buffer_state_seg_sdu = remaining_seg_bytes == 0 ? 0 : (header_size + so_size + remaining_seg_bytes);
expected_buffer_state = buffer_state_full_sdus + buffer_state_seg_sdu;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
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, pdu_size_first); // 2 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_first, len);
} else {
// Middle or last segment, SO present
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_continued); // 4 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_continued, len);
}
}
// Deliver dummy status report with nack range betwen PDU 6 and 10.
rlc_am_nr_status_pdu_t status(sn_size);
status.ack_sn = 5;
rlc_status_nack_t nack = {};
nack.nack_sn = 1;
nack.has_nack_range = true;
nack.nack_range = 3;
nack.has_so = true;
nack.so_start = 2;
nack.so_end = 0;
status.push_nack(nack);
byte_buffer_t status_pdu;
rlc_am_nr_write_status_pdu(status, sn_size, &status_pdu);
rlc1.write_pdu(status_pdu.msg, status_pdu.N_bytes);
TESTASSERT_EQ(2 * pdu_size_first + 3 * pdu_size_continued, rlc1.get_buffer_state());
return SRSRAN_SUCCESS;
}
int rx_nack_range_with_so_starting_with_full_sdu_test(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
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);
std::string str =
"Rx NACK range test with SO starting with full SDU (" + std::to_string(to_number(sn_size)) + " bit SN)";
test_delimit_logger delimiter(str.c_str());
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 rlc_cnfg = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
rlc_cnfg.am_nr.t_poll_retx = -1;
if (not rlc1.configure(rlc_cnfg)) {
return -1;
}
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
int n_sdu_bufs = 5;
int n_pdu_bufs = 15;
// Push 5 SDUs into RLC1
std::vector<unique_byte_buffer_t> sdu_bufs(n_sdu_bufs);
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 (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 = payload_size; // 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]));
}
uint32_t expected_buffer_state = (header_size + payload_size) * n_sdu_bufs;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
constexpr uint32_t so_size = 2;
constexpr uint32_t segment_size = 1;
uint32_t pdu_size_whole = header_size + payload_size;
uint32_t pdu_size_first = header_size + segment_size;
uint32_t pdu_size_continued = header_size + so_size + segment_size;
// Read 15 PDUs from RLC1
std::vector<unique_byte_buffer_t> pdu_bufs(n_pdu_bufs);
for (int i = 0; i < n_pdu_bufs; i++) {
// First also test buffer state
uint32_t remaining_total_bytes = (payload_size * n_sdu_bufs) - (i * segment_size);
uint32_t remaining_full_sdus = remaining_total_bytes / payload_size;
uint32_t remaining_seg_bytes = remaining_total_bytes % payload_size;
uint32_t buffer_state_full_sdus = (header_size + payload_size) * remaining_full_sdus;
uint32_t buffer_state_seg_sdu = remaining_seg_bytes == 0 ? 0 : (header_size + so_size + remaining_seg_bytes);
expected_buffer_state = buffer_state_full_sdus + buffer_state_seg_sdu;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
pdu_bufs[i] = srsran::make_byte_buffer();
if (i == 3) {
// Special handling for SDU SN=1 (i==3): send as a whole, not segmented
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_whole); // 2 bytes for header + 3 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_whole, len);
// update i to skip 2 segments
i += 2;
} else {
if (i == 0 || i == 6 || i == 9 || i == 12) {
// First segment, no SO
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_first); // 2 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_first, len);
} else {
// Middle or last segment, SO present
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_continued); // 4 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_continued, len);
}
}
}
// Deliver dummy status report with nack range betwen PDU 4 and 10.
rlc_am_nr_status_pdu_t status(sn_size);
status.ack_sn = 5;
rlc_status_nack_t nack = {};
nack.nack_sn = 1;
nack.has_nack_range = true;
nack.nack_range = 3;
nack.has_so = true;
nack.so_start = 0;
nack.so_end = 0;
status.push_nack(nack);
byte_buffer_t status_pdu;
rlc_am_nr_write_status_pdu(status, sn_size, &status_pdu);
rlc1.write_pdu(status_pdu.msg, status_pdu.N_bytes);
TESTASSERT_EQ(pdu_size_whole + 2 * pdu_size_first + 2 * pdu_size_continued, rlc1.get_buffer_state());
return SRSRAN_SUCCESS;
}
int rx_nack_range_with_so_ending_with_full_sdu_test(rlc_am_nr_sn_size_t sn_size)
{
rlc_am_tester tester(true, nullptr);
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);
std::string str =
"Rx NACK range test with SO starting with full SDU (" + std::to_string(to_number(sn_size)) + " bit SN)";
test_delimit_logger delimiter(str.c_str());
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 rlc_cnfg = rlc_config_t::default_rlc_am_nr_config(to_number(sn_size));
rlc_cnfg.am_nr.t_poll_retx = -1;
if (not rlc1.configure(rlc_cnfg)) {
return -1;
}
// after configuring entity
TESTASSERT(0 == rlc1.get_buffer_state());
int n_sdu_bufs = 5;
int n_pdu_bufs = 15;
// Push 5 SDUs into RLC1
std::vector<unique_byte_buffer_t> sdu_bufs(n_sdu_bufs);
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 (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 = payload_size; // 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]));
}
uint32_t expected_buffer_state = (header_size + payload_size) * n_sdu_bufs;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
constexpr uint32_t so_size = 2;
constexpr uint32_t segment_size = 1;
uint32_t pdu_size_whole = header_size + payload_size;
uint32_t pdu_size_first = header_size + segment_size;
uint32_t pdu_size_continued = header_size + so_size + segment_size;
// Read 15 PDUs from RLC1
std::vector<unique_byte_buffer_t> pdu_bufs(n_pdu_bufs);
for (int i = 0; i < n_pdu_bufs; i++) {
// First also test buffer state
uint32_t remaining_total_bytes = (payload_size * n_sdu_bufs) - (i * segment_size);
uint32_t remaining_full_sdus = remaining_total_bytes / payload_size;
uint32_t remaining_seg_bytes = remaining_total_bytes % payload_size;
uint32_t buffer_state_full_sdus = (header_size + payload_size) * remaining_full_sdus;
uint32_t buffer_state_seg_sdu = remaining_seg_bytes == 0 ? 0 : (header_size + so_size + remaining_seg_bytes);
expected_buffer_state = buffer_state_full_sdus + buffer_state_seg_sdu;
TESTASSERT_EQ(expected_buffer_state, rlc1.get_buffer_state());
pdu_bufs[i] = srsran::make_byte_buffer();
if (i == 9) {
// Special handling for SDU SN=3 (i==9): send as a whole, not segmented
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_whole); // 2 bytes for header + 3 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_whole, len);
// update i to skip 2 segments
i += 2;
} else {
if (i == 0 || i == 3 || i == 6 || i == 12) {
// First segment, no SO
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_first); // 2 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_first, len);
} else {
// Middle or last segment, SO present
uint32_t len = rlc1.read_pdu(pdu_bufs[i]->msg, pdu_size_continued); // 4 bytes for header + 1 byte payload
pdu_bufs[i]->N_bytes = len;
TESTASSERT_EQ(pdu_size_continued, len);
}
}
}
// Deliver dummy status report with nack range betwen PDU 6 and 12.
rlc_am_nr_status_pdu_t status(sn_size);
status.ack_sn = 5;
rlc_status_nack_t nack = {};
nack.nack_sn = 1;
nack.has_nack_range = true;
nack.nack_range = 3;
nack.has_so = true;
nack.so_start = 2;
nack.so_end = rlc_status_nack_t::so_end_of_sdu;
status.push_nack(nack);
byte_buffer_t status_pdu;
rlc_am_nr_write_status_pdu(status, sn_size, &status_pdu);
rlc1.write_pdu(status_pdu.msg, status_pdu.N_bytes);
TESTASSERT_EQ(1 * pdu_size_first + 3 * pdu_size_continued + pdu_size_whole, rlc1.get_buffer_state());
return SRSRAN_SUCCESS;
}
int out_of_order_status(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("out of order status report ({} 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_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());
if (not rlc1.configure(rlc_config_t::default_rlc_am_nr_config(to_number(sn_size)))) {
return -1;
}
TESTASSERT_EQ(0, rlc1.get_buffer_state());
basic_test_tx(&rlc1, pdu_bufs, sn_size);
// Status 1, ACK SN=2, NACK_SN = 1
rlc_am_nr_status_pdu_t status1(sn_size);
status1.ack_sn = 2;
{
rlc_status_nack_t nack = {};
nack.nack_sn = 1;
status1.push_nack(nack);
}
// Status 2, ACK SN=5, NACK SN = 3
rlc_am_nr_status_pdu_t status2(sn_size);
status2.ack_sn = 5;
{
rlc_status_nack_t nack = {};
nack.nack_sn = 3;
status2.push_nack(nack);
}
// pack into PDU
byte_buffer_t status1_pdu;
rlc_am_nr_write_status_pdu(status1, sn_size, &status1_pdu);
// pack into PDU
byte_buffer_t status2_pdu;
rlc_am_nr_write_status_pdu(status2, sn_size, &status2_pdu);
// Write status 2 to RLC1
rlc1.write_pdu(status2_pdu.msg, status2_pdu.N_bytes);
// Check TX_NEXT_ACK
{
rlc_am_nr_tx_state_t st = tx1->get_tx_state();
TESTASSERT_EQ(3, st.tx_next_ack); // SN=3 was nacked on status report 2
TESTASSERT_EQ(2, tx1->get_tx_window_utilization()); // 2 PDUs still in TX_WINDOW
}
// Write status 1 to RLC1
rlc1.write_pdu(status1_pdu.msg, status1_pdu.N_bytes);
// Check TX_NEXT_ACK
{
rlc_am_nr_tx_state_t st = tx1->get_tx_state();
TESTASSERT_EQ(3, st.tx_next_ack);
TESTASSERT_EQ(2, tx1->get_tx_window_utilization());
}
// Check statistics
rlc_bearer_metrics_t metrics1 = rlc1.get_metrics();
return SRSRAN_SUCCESS;
}
// If we lose the status report
int lost_status_and_advanced_rx_window(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("Lost status report and advance RX window ({} 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));
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);
// Fill up the RX window
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 < 10; ++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);
}
// We got the polling bit, so we generate the status report.
TESTASSERT_EQ(3, rlc2.get_buffer_state());
// Read status PDU
{
unique_byte_buffer_t status_buf = srsran::make_byte_buffer();
status_buf->N_bytes = rlc2.read_pdu(status_buf->msg, 3);
}
TESTASSERT_EQ(0, rlc2.get_buffer_state());
// We do not write the status report into RLC 1
// We step trought the timers to let t-PollRetransmission expire
TESTASSERT_EQ(0, rlc1.get_buffer_state());
for (int t = 0; t < 45; t++) {
timers.step_all();
}
TESTASSERT_EQ(header_size + payload_size, rlc1.get_buffer_state());
// Read RETX of POLL_SN and check if it triggered the
// Status report
{
unique_byte_buffer_t pdu_buf = srsran::make_byte_buffer();
pdu_buf->N_bytes = rlc1.read_pdu(pdu_buf->msg, 100);
TESTASSERT_EQ(0, rlc2.get_buffer_state());
rlc2.write_pdu(pdu_buf->msg, pdu_buf->N_bytes);
TESTASSERT_EQ(3, 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);
timer_handler timers(8);
byte_buffer_t pdu_bufs[NBUFS];
auto& test_logger = srslog::fetch_basic_logger("TESTER ");
test_delimit_logger delimiter("Full RX window and t-Reassmbly expiry test ({} 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));
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);
// Fill up the RX window
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 < am_window_size(sn_size); ++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 PDUs into RLC 2
// Do not write SN=0 to fill up the RX window
if (sn != 0) {
rlc2.write_pdu(pdu_buf->msg, pdu_buf->N_bytes);
}
}
// Step timers until reassambly timeout expires
for (int cnt = 0; cnt < 35; cnt++) {
timers.step_all();
}
// 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);
rlc1.write_pdu(status_buf->msg, status_buf->N_bytes);
TESTASSERT_EQ(header_size + payload_size, rlc1.get_buffer_state());
}
// Check Rx_Status_Highest
{
rlc_am_nr_rx_state_t st = rx2->get_rx_state();
TESTASSERT_EQ(2048, st.rx_highest_status);
}
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<srsran::log_sink_message_spy>(
new srsran::log_sink_message_spy(srslog::get_default_log_formatter())))) {
return SRSRAN_ERROR;
}
auto* spy = static_cast<srsran::log_sink_message_spy*>(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();
std::initializer_list<rlc_am_nr_sn_size_t> sn_sizes = {rlc_am_nr_sn_size_t::size12bits,
rlc_am_nr_sn_size_t::size18bits};
for (auto sn_size : sn_sizes) {
TESTASSERT(window_checker_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(retx_segmentation_required_checker_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(basic_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(lost_pdu_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(lost_pdu_duplicated_nack_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(lost_pdus_trimmed_nack_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(clean_retx_queue_of_acked_sdus_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(basic_segmentation_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(segment_retx_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(segment_retx_and_loose_segments_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(retx_segment_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(handle_status_of_non_tx_last_segment(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(max_retx_lost_sdu_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(max_retx_lost_segments_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(discard_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(poll_pdu(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(poll_byte(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(poll_retx(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(poll_retx_expiry(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(rx_nack_range_no_so_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(rx_nack_range_with_so_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(rx_nack_range_with_so_starting_with_full_sdu_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(rx_nack_range_with_so_ending_with_full_sdu_test(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(out_of_order_status(sn_size) == SRSRAN_SUCCESS);
TESTASSERT(lost_status_and_advanced_rx_window(sn_size) == SRSRAN_SUCCESS);
}
TESTASSERT(full_rx_window_t_reassembly_expiry(rlc_am_nr_sn_size_t::size12bits) == SRSRAN_SUCCESS);
return SRSRAN_SUCCESS;
}