srsLTE/srsenb/test/mac/scheduler_test_utils.h

/*
 * Copyright 2013-2019 Software Radio Systems Limited
 *
 * This file is part of srsLTE.
 *
 * srsLTE is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * srsLTE is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * A copy of the GNU Affero General Public License can be found in
 * the LICENSE file in the top-level directory of this distribution
 * and at http://www.gnu.org/licenses/.
 *
 */

#ifndef SRSLTE_SCHEDULER_TEST_UTILS_H
#define SRSLTE_SCHEDULER_TEST_UTILS_H

#include "srsenb/hdr/stack/mac/scheduler.h"
#include "srslte/common/test_common.h"
#include "srslte/interfaces/sched_interface.h"
#include <algorithm>
#include <chrono>
#include <random>

/***************************
 * Setup Random generators
 **************************/

// uint32_t const seed = std::chrono::system_clock::now().time_since_epoch().count();
uint32_t const seed = 2452071795;
// uint32_t const seed = 1581009287; // prb==25
std::default_random_engine            rand_gen(seed);
std::uniform_real_distribution<float> unif_dist(0, 1.0);
bool                                  check_old_pids = false;

float randf()
{
  return unif_dist(rand_gen);
}

template <typename Integer>
Integer rand_int(Integer lb, Integer ub)
{
  std::uniform_int_distribution<Integer> dist(lb, ub);
  return dist(rand_gen);
}

/*****************************
 * Setup Sched Configuration
 ****************************/

srsenb::sched_interface::cell_cfg_t generate_default_cell_cfg(uint32_t nof_prb)
{
  srsenb::sched_interface::cell_cfg_t cell_cfg     = {};
  srslte_cell_t&                      cell_cfg_phy = cell_cfg.cell;

  /* Set PHY cell configuration */
  cell_cfg_phy.id              = 1;
  cell_cfg_phy.cp              = SRSLTE_CP_NORM;
  cell_cfg_phy.nof_ports       = 1;
  cell_cfg_phy.nof_prb         = nof_prb;
  cell_cfg_phy.phich_length    = SRSLTE_PHICH_NORM;
  cell_cfg_phy.phich_resources = SRSLTE_PHICH_R_1;

  cell_cfg.sibs[0].len       = 18;
  cell_cfg.sibs[0].period_rf = 8;
  cell_cfg.sibs[1].len       = 41;
  cell_cfg.sibs[1].period_rf = 16;
  cell_cfg.si_window_ms      = 40;
  cell_cfg.nrb_pucch         = 2;
  cell_cfg.prach_freq_offset = (cell_cfg_phy.nof_prb == 6) ? 0 : 2;
  cell_cfg.prach_rar_window  = 3;
  cell_cfg.maxharq_msg3tx    = 3;

  return cell_cfg;
}

srsenb::sched_interface::ue_cfg_t generate_default_ue_cfg()
{
  srsenb::sched_interface::ue_cfg_t ue_cfg = {};

  ue_cfg.aperiodic_cqi_period = 40;
  ue_cfg.maxharq_tx           = 5;
  ue_cfg.dl_cfg.tm            = SRSLTE_TM1;
  ue_cfg.supported_cc_list.resize(1);
  ue_cfg.supported_cc_list[0].enb_cc_idx = 0;
  ue_cfg.supported_cc_list[0].active     = true;
  ue_cfg.ue_bearers[0].direction         = srsenb::sched_interface::ue_bearer_cfg_t::BOTH;

  return ue_cfg;
}

/*****************************
 *   Event Setup Helpers
 ****************************/

// Struct that represents all the events that take place in a TTI
struct tti_ev {
  struct user_buffer_ev {
    uint32_t sr_data      = 0; ///< update BSR
    uint32_t dl_data      = 0; ///< update DL buffer newtx
    uint32_t dl_nof_retxs = 0; ///< update DL buffer retx
  };
  struct user_cfg_ev {
    uint16_t                                                  rnti;
    std::unique_ptr<srsenb::sched_interface::ue_cfg_t>        ue_cfg;           ///< optional ue_cfg call
    std::unique_ptr<srsenb::sched_interface::ue_bearer_cfg_t> bearer_cfg;       ///< optional bearer_cfg call
    std::unique_ptr<user_buffer_ev>                           buffer_ev;        ///< update of a user dl/ul buffer
    bool                                                      rem_user = false; ///< whether to remove a ue
  };
  std::vector<user_cfg_ev> user_updates;
};

struct sim_sched_args {
  uint32_t                                         nof_ttis;
  float                                            P_retx;
  srsenb::sched_interface::ue_cfg_t                ue_cfg;
  srsenb::sched_interface::ue_bearer_cfg_t         bearer_cfg;
  std::vector<srsenb::sched_interface::cell_cfg_t> cell_cfg;
};

// generate all events up front
struct sched_sim_events {
  sim_sched_args      sim_args; ///< arguments used to generate TTI events
  std::vector<tti_ev> tti_events;
};

struct sched_sim_event_generator {
  uint16_t next_rnti   = 70;
  uint32_t current_tti = 0;

  struct user_data {
    uint16_t rnti;
    uint32_t tti_start;
    uint32_t tti_duration;
  };
  std::vector<user_data> current_users;

  // generated events
  std::vector<tti_ev> tti_events;

  void step_tti(uint32_t nof_ttis = 1)
  {
    current_tti += nof_ttis;
    if (current_tti >= tti_events.size()) {
      tti_events.resize(current_tti + 1);
    }
    rem_old_users();
  }

  void step_until(uint32_t tti)
  {
    if (current_tti >= tti) {
      // error
      return;
    }
    current_tti = tti;
    if (current_tti >= tti_events.size()) {
      tti_events.resize(current_tti + 1);
    }
    rem_old_users();
  }

  tti_ev::user_cfg_ev* add_new_default_user(uint32_t duration)
  {
    std::vector<tti_ev::user_cfg_ev>& user_updates = tti_events[current_tti].user_updates;
    user_updates.emplace_back();
    auto& user = user_updates.back();
    user.rnti  = next_rnti++;
    // creates a user with one supported CC (PRACH stage)
    user.ue_cfg.reset(new srsenb::sched_interface::ue_cfg_t{generate_default_ue_cfg()});
    current_users.emplace_back();
    current_users.back().rnti         = user.rnti;
    current_users.back().tti_start    = current_tti;
    current_users.back().tti_duration = duration;
    return &user;
  }

  int add_dl_data(uint16_t rnti, uint32_t new_data)
  {
    TESTASSERT(user_exists(rnti));
    tti_ev::user_cfg_ev* user = get_user_cfg(rnti);
    user->buffer_ev.reset(new tti_ev::user_buffer_ev{});
    user->buffer_ev->dl_data = new_data;
    return SRSLTE_SUCCESS;
  }

  int add_ul_data(uint16_t rnti, uint32_t new_data)
  {
    TESTASSERT(user_exists(rnti));
    tti_ev::user_cfg_ev* user = get_user_cfg(rnti);
    TESTASSERT(user != nullptr);
    user->buffer_ev.reset(new tti_ev::user_buffer_ev{});
    user->buffer_ev->sr_data = new_data;
    return SRSLTE_SUCCESS;
  }

  tti_ev::user_cfg_ev* user_reconf(uint16_t rnti)
  {
    if (not user_exists(rnti)) {
      return nullptr;
    }
    tti_ev::user_cfg_ev* user = get_user_cfg(rnti);
    user->ue_cfg.reset(new srsenb::sched_interface::ue_cfg_t{generate_default_ue_cfg()});
    // it should by now have a DRB1. Add other DRBs manually
    user->ue_cfg->ue_bearers[2].direction = srsenb::sched_interface::ue_bearer_cfg_t::BOTH;
    return user;
  }

private:
  tti_ev::user_cfg_ev* get_user_cfg(uint16_t rnti)
  {
    std::vector<tti_ev::user_cfg_ev>& user_updates = tti_events[current_tti].user_updates;
    auto                              it           = std::find_if(
        user_updates.begin(), user_updates.end(), [&rnti](tti_ev::user_cfg_ev& user) { return user.rnti == rnti; });
    if (it == user_updates.end()) {
      user_updates.emplace_back();
      user_updates.back().rnti = rnti;
      return &user_updates.back();
    }
    return &(*it);
  }

  bool user_exists(uint16_t rnti)
  {
    return std::find_if(current_users.begin(), current_users.end(), [&rnti](const user_data& u) {
             return u.rnti == rnti;
           }) != current_users.end();
  }

  void rem_old_users()
  {
    // remove users that pass their connection duration
    auto rem_it = std::remove_if(current_users.begin(), current_users.end(), [this](const user_data& u) {
      return u.tti_start + u.tti_duration < current_tti;
    });

    // set the call rem_user(...) at the right tti
    for (auto it = rem_it; it != current_users.end(); ++it) {
      uint32_t rem_tti = it->tti_start + it->tti_duration;
      auto&    l       = tti_events[rem_tti].user_updates;
      auto     user_it = std::find_if(l.begin(), l.end(), [&it](tti_ev::user_cfg_ev& u) { return it->rnti == u.rnti; });
      if (user_it == l.end()) {
        l.emplace_back();
        l.back().rem_user = true;
      } else {
        user_it->rem_user = true;
      }
    }

    current_users.erase(rem_it, current_users.end());
  }
};

#endif // SRSLTE_SCHEDULER_TEST_UTILS_H