| /* (C) 2018 by sysmocom s.f.m.c. GmbH <info@sysmocom.de> |
| * |
| * Author: Stefan Sperling <ssperling@sysmocom.de> |
| * |
| * All Rights Reserved |
| * |
| * This program 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. |
| * |
| * This program 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. |
| * |
| * You should have received a copy of the GNU Affero General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| * |
| */ |
| |
| #pragma once |
| |
| #include <stdbool.h> |
| #include <stdint.h> |
| |
| #include <osmocom/core/timer.h> |
| #include <osmocom/gsm/protocol/gsm_04_08.h> |
| |
| #define ACC_MGR_QUANTUM_DEFAULT 20 /* 20 seconds */ |
| |
| /* Manage rotating subset of allowed Access Class as per configuration */ |
| struct acc_mgr { |
| struct gsm_bts *bts; /*!< backpointer to BTS using this ACC manager */ |
| /* Administrative Maximum Number of ACC 0-9 to be allowed at the same time. |
| Configurable through VTY cmd "access-control-class-roundrobin", |
| defaults to all allowed (10) */ |
| uint8_t len_allowed_adm; |
| /* Further limiting the number of ACC to use. It may be lower due |
| to ramping, based for instance on channel or system load. */ |
| uint8_t len_allowed_ramp; |
| |
| /* Time until next subset is generated */ |
| uint32_t rotation_time_sec; |
| struct osmo_timer_list rotate_timer; |
| |
| /* Bitmask containing subset of allowed ACC 0-9 on current rotation iteration */ |
| uint16_t allowed_subset_mask; |
| /* Number of bits (ACC) set in allowed_subset_mask: 0->min(len_allowed_ramp, len_allowed_adm) */ |
| uint8_t allowed_subset_mask_count; |
| /* Number of ACC 0-9 allowed as per adminsitrative (permanent) config. */ |
| uint8_t allowed_permanent_count; |
| }; |
| |
| void acc_mgr_init(struct acc_mgr *acc_mgr, struct gsm_bts *bts); |
| uint8_t acc_mgr_get_len_allowed_adm(struct acc_mgr *acc_mgr); |
| uint8_t acc_mgr_get_len_allowed_ramp(struct acc_mgr *acc_mgr); |
| void acc_mgr_set_len_allowed_adm(struct acc_mgr *acc_mgr, uint8_t len_allowed_adm); |
| void acc_mgr_set_len_allowed_ramp(struct acc_mgr *acc_mgr, uint8_t len_allowed_ramp); |
| void acc_mgr_set_rotation_time(struct acc_mgr *acc_mgr, uint32_t rotation_time_sec); |
| void acc_mgr_perm_subset_changed(struct acc_mgr *acc_mgr, struct gsm48_rach_control *rach_control); |
| void acc_mgr_apply_acc(struct acc_mgr *acc_mgr, struct gsm48_rach_control *rach_control); |
| |
| /*! |
| * Access control class (ACC) ramping is used to slowly make the cell available to |
| * an increasing number of MS. This avoids overload at startup time in cases where |
| * a lot of MS would discover the new cell and try to connect to it all at once. |
| */ |
| |
| #define ACC_RAMP_STEP_SIZE_MIN 1 /* allow at most 1 new ACC per ramp step */ |
| #define ACC_RAMP_STEP_SIZE_DEFAULT ACC_RAMP_STEP_SIZE_MIN |
| #define ACC_RAMP_STEP_SIZE_MAX 10 /* allow all ACC in one step (effectively disables ramping) */ |
| |
| #define ACC_RAMP_STEP_INTERVAL_MIN 5 /* 5 seconds */ |
| #define ACC_RAMP_STEP_INTERVAL_MAX 600 /* 10 minutes */ |
| |
| #define ACC_RAMP_CHAN_LOAD_THRESHOLD_LOW 71 |
| #define ACC_RAMP_CHAN_LOAD_THRESHOLD_UP 89 |
| |
| /*! |
| * Data structure used to manage ACC ramping. Please avoid setting or reading fields |
| * in this structure directly. Use the accessor functions below instead. |
| */ |
| struct acc_ramp { |
| struct gsm_bts *bts; /*!< backpointer to BTS using this ACC ramp */ |
| |
| bool acc_ramping_enabled; /*!< whether ACC ramping is enabled */ |
| |
| /*! |
| * This controls the maximum number of ACCs to allow per ramping step (1 - 10). |
| * The compile-time default value is ACC_RAMP_STEP_SIZE_DEFAULT. |
| * This value can be changed by VTY configuration. |
| * A value of ACC_RAMP_STEP_SIZE_MAX effectively disables ramping. |
| */ |
| unsigned int step_size; |
| |
| /*! |
| * Ramping step interval in seconds. |
| * This value depends on the current BTS channel load average, unless |
| * it has been overridden by VTY configuration. |
| */ |
| unsigned int step_interval_sec; |
| struct osmo_timer_list step_timer; |
| |
| /*! |
| * Channel Load Upper/Lower Thresholds: |
| * They control how ramping subset size of allowed ACCs changes in |
| * relation to current channel load (%, 0-100): Under the lower |
| * threshold, subset size may be increased; above the upper threshold, |
| * subset size may be decreased. |
| */ |
| unsigned int chan_load_lower_threshold; |
| unsigned int chan_load_upper_threshold; |
| }; |
| |
| /*! |
| * Enable or disable ACC ramping. |
| * When enabled, ramping begins once acc_ramp_start() is called. |
| * When disabled, an ACC ramping process in progress will continue |
| * unless acc_ramp_abort() is called as well. |
| * \param[in] acc_ramp Pointer to acc_ramp structure. |
| */ |
| static inline void acc_ramp_set_enabled(struct acc_ramp *acc_ramp, bool enable) |
| { |
| acc_ramp->acc_ramping_enabled = enable; |
| } |
| |
| /*! |
| * Return true if ACC ramping is currently enabled, else false. |
| * \param[in] acc_ramp Pointer to acc_ramp structure. |
| */ |
| static inline bool acc_ramp_is_enabled(struct acc_ramp *acc_ramp) |
| { |
| return acc_ramp->acc_ramping_enabled; |
| } |
| |
| /*! |
| * Return the current ACC ramp step size. |
| * \param[in] acc_ramp Pointer to acc_ramp structure. |
| */ |
| static inline unsigned int acc_ramp_get_step_size(struct acc_ramp *acc_ramp) |
| { |
| return acc_ramp->step_size; |
| } |
| |
| /*! |
| * Return the current ACC ramp step interval (in seconds) |
| * \param[in] acc_ramp Pointer to acc_ramp structure. |
| */ |
| static inline unsigned int acc_ramp_get_step_interval(struct acc_ramp *acc_ramp) |
| { |
| return acc_ramp->step_interval_sec; |
| } |
| |
| /*! |
| * Return the current ACC ramp step interval (in seconds) |
| * \param[in] acc_ramp Pointer to acc_ramp structure. |
| */ |
| static inline unsigned int acc_ramp_is_running(struct acc_ramp *acc_ramp) |
| { |
| return acc_ramp->step_interval_sec; |
| } |
| |
| void acc_ramp_init(struct acc_ramp *acc_ramp, struct gsm_bts *bts); |
| int acc_ramp_set_step_size(struct acc_ramp *acc_ramp, unsigned int step_size); |
| int acc_ramp_set_step_interval(struct acc_ramp *acc_ramp, unsigned int step_interval); |
| int acc_ramp_set_chan_load_thresholds(struct acc_ramp *acc_ramp, unsigned int low_threshold, unsigned int up_threshold); |
| void acc_ramp_trigger(struct acc_ramp *acc_ramp); |
| void acc_ramp_abort(struct acc_ramp *acc_ramp); |