| /* gprs_rlcmac.cpp |
| * |
| * Copyright (C) 2012 Ivan Klyuchnikov |
| * Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu> |
| * Copyright (C) 2013 by Holger Hans Peter Freyther |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version 2 |
| * 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 General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| */ |
| |
| #include <gprs_rlcmac.h> |
| #include <gprs_debug.h> |
| #include <bts.h> |
| #include <tbf.h> |
| #include <gprs_ms.h> |
| #include <pcu_utils.h> |
| |
| #include <errno.h> |
| #include <values.h> |
| |
| /* Consider a PDCH as idle if has at most this number of TBFs assigned to it */ |
| #define PDCH_IDLE_TBF_THRESH 1 |
| |
| /* 3GPP TS 05.02 Annex B.1 */ |
| |
| #define MS_NA 255 /* N/A */ |
| #define MS_A 254 /* 1 with hopping, 0 without */ |
| #define MS_B 253 /* 1 with hopping, 0 without (change Rx to Tx)*/ |
| #define MS_C 252 /* 1 with hopping, 0 without (change Tx to Rx)*/ |
| |
| struct gprs_ms_multislot_class { |
| uint8_t rx, tx, sum; /* Maximum Number of Slots: RX, Tx, Sum Rx+Tx */ |
| uint8_t ta, tb, ra, rb; /* Minimum Number of Slots */ |
| uint8_t type; /* Type of Mobile */ |
| }; |
| |
| static const struct gprs_ms_multislot_class gprs_ms_multislot_class[32] = { |
| /* M-S Class | Max # of slots | Min # of slots | Type */ |
| /* | Rx Tx Sum | Tta Ttb Tra Trb | */ |
| /* N/A */ { MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA }, |
| /* 1 */ { 1, 1, 2, 3, 2, 4, 2, 1 }, |
| /* 2 */ { 2, 1, 3, 3, 2, 3, 1, 1 }, |
| /* 3 */ { 2, 2, 3, 3, 2, 3, 1, 1 }, |
| /* 4 */ { 3, 1, 4, 3, 1, 3, 1, 1 }, |
| /* 5 */ { 2, 2, 4, 3, 1, 3, 1, 1 }, |
| /* 6 */ { 3, 2, 4, 3, 1, 3, 1, 1 }, |
| /* 7 */ { 3, 3, 4, 3, 1, 3, 1, 1 }, |
| /* 8 */ { 4, 1, 5, 3, 1, 2, 1, 1 }, |
| /* 9 */ { 3, 2, 5, 3, 1, 2, 1, 1 }, |
| /* 10 */ { 4, 2, 5, 3, 1, 2, 1, 1 }, |
| /* 11 */ { 4, 3, 5, 3, 1, 2, 1, 1 }, |
| /* 12 */ { 4, 4, 5, 2, 1, 2, 1, 1 }, |
| /* 13 */ { 3, 3, MS_NA, MS_NA, MS_A, 3, MS_A, 2 }, |
| /* 14 */ { 4, 4, MS_NA, MS_NA, MS_A, 3, MS_A, 2 }, |
| /* 15 */ { 5, 5, MS_NA, MS_NA, MS_A, 3, MS_A, 2 }, |
| /* 16 */ { 6, 6, MS_NA, MS_NA, MS_A, 2, MS_A, 2 }, |
| /* 17 */ { 7, 7, MS_NA, MS_NA, MS_A, 1, 0, 2 }, |
| /* 18 */ { 8, 8, MS_NA, MS_NA, 0, 0, 0, 2 }, |
| /* 19 */ { 6, 2, MS_NA, 3, MS_B, 2, MS_C, 1 }, |
| /* 20 */ { 6, 3, MS_NA, 3, MS_B, 2, MS_C, 1 }, |
| /* 21 */ { 6, 4, MS_NA, 3, MS_B, 2, MS_C, 1 }, |
| /* 22 */ { 6, 4, MS_NA, 2, MS_B, 2, MS_C, 1 }, |
| /* 23 */ { 6, 6, MS_NA, 2, MS_B, 2, MS_C, 1 }, |
| /* 24 */ { 8, 2, MS_NA, 3, MS_B, 2, MS_C, 1 }, |
| /* 25 */ { 8, 3, MS_NA, 3, MS_B, 2, MS_C, 1 }, |
| /* 26 */ { 8, 4, MS_NA, 3, MS_B, 2, MS_C, 1 }, |
| /* 27 */ { 8, 4, MS_NA, 2, MS_B, 2, MS_C, 1 }, |
| /* 28 */ { 8, 6, MS_NA, 2, MS_B, 2, MS_C, 1 }, |
| /* 29 */ { 8, 8, MS_NA, 2, MS_B, 2, MS_C, 1 }, |
| /* N/A */ { MS_NA,MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA }, |
| /* N/A */ { MS_NA,MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA }, |
| }; |
| |
| static char *set_flag_chars(char *buf, uint8_t val, char set_char, char unset_char = 0) |
| { |
| int i; |
| |
| for (i = 0; i < 8; i += 1, val = val >> 1) { |
| if (val & 1) |
| buf[i] = set_char; |
| else if (unset_char) |
| buf[i] = unset_char; |
| } |
| |
| return buf; |
| } |
| |
| static bool test_and_set_bit(uint32_t *bits, size_t elem) |
| { |
| bool was_set = bits[elem/32] & (1 << (elem % 32)); |
| bits[elem/32] |= (1 << (elem % 32)); |
| |
| return was_set; |
| } |
| |
| static inline int8_t find_free_usf(struct gprs_rlcmac_pdch *pdch) |
| { |
| uint8_t usf_map = 0; |
| uint8_t usf; |
| |
| usf_map = pdch->assigned_usf(); |
| if (usf_map == (1 << 7) - 1) |
| return -1; |
| |
| /* look for USF, don't use USF=7 */ |
| for (usf = 0; usf < 7; usf++) { |
| if (!(usf_map & (1 << usf))) |
| return usf; |
| } |
| |
| return -1; |
| } |
| |
| static inline int8_t find_free_tfi(struct gprs_rlcmac_pdch *pdch, |
| enum gprs_rlcmac_tbf_direction dir) |
| { |
| uint32_t tfi_map = 0; |
| int8_t tfi; |
| |
| tfi_map = pdch->assigned_tfi(dir); |
| if (tfi_map == 0xffffffffUL) |
| return -1; |
| |
| /* look for USF, don't use USF=7 */ |
| for (tfi = 0; tfi < 32; tfi++) { |
| if (!(tfi_map & (1 << tfi))) |
| return tfi; |
| } |
| |
| return -1; |
| } |
| |
| static int find_possible_pdchs(struct gprs_rlcmac_trx *trx, |
| size_t max_slots, |
| uint8_t mask, const char *mask_reason = NULL) |
| { |
| unsigned ts; |
| int valid_ts_set = 0; |
| int8_t last_tsc = -1; /* must be signed */ |
| |
| for (ts = 0; ts < ARRAY_SIZE(trx->pdch); ts++) { |
| struct gprs_rlcmac_pdch *pdch; |
| |
| pdch = &trx->pdch[ts]; |
| if (!pdch->is_enabled()) { |
| LOGP(DRLCMAC, LOGL_DEBUG, "- Skipping TS %d, because " |
| "not enabled\n", ts); |
| continue; |
| } |
| |
| if (((1 << ts) & mask) == 0) { |
| if (mask_reason) |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Skipping TS %d, because %s\n", |
| ts, mask_reason); |
| continue; |
| } |
| |
| if (max_slots > 1) { |
| /* check if TSC changes, see TS 45.002, 6.4.2 */ |
| if (last_tsc < 0) |
| last_tsc = pdch->tsc; |
| else if (last_tsc != pdch->tsc) { |
| LOGP(DRLCMAC, LOGL_ERROR, |
| "Skipping TS %d of TRX=%d, because it " |
| "has different TSC than lower TS of TRX. " |
| "In order to allow multislot, all " |
| "slots must be configured with the same " |
| "TSC!\n", ts, trx->trx_no); |
| continue; |
| } |
| } |
| |
| valid_ts_set |= 1 << ts; |
| } |
| |
| return valid_ts_set; |
| } |
| |
| static int compute_usage_by_num_tbfs(struct gprs_rlcmac_pdch *pdch, |
| enum gprs_rlcmac_tbf_direction dir) |
| { |
| return pdch->num_tbfs(dir); |
| } |
| |
| static int compute_usage_by_reservation(struct gprs_rlcmac_pdch *pdch, |
| enum gprs_rlcmac_tbf_direction) |
| { |
| return |
| pdch->num_reserved(GPRS_RLCMAC_DL_TBF) + |
| pdch->num_reserved(GPRS_RLCMAC_UL_TBF); |
| } |
| |
| static int compute_usage_for_algo_a(struct gprs_rlcmac_pdch *pdch, |
| enum gprs_rlcmac_tbf_direction dir) |
| { |
| int usage = |
| pdch->num_tbfs(GPRS_RLCMAC_DL_TBF) + |
| pdch->num_tbfs(GPRS_RLCMAC_UL_TBF) + |
| compute_usage_by_reservation(pdch, dir); |
| |
| if (pdch->assigned_tfi(reverse(dir)) == 0xffffffff) |
| /* No TFI in the opposite direction, avoid it */ |
| usage += 32; |
| |
| return usage; |
| |
| } |
| |
| static int find_least_busy_pdch(struct gprs_rlcmac_trx *trx, |
| enum gprs_rlcmac_tbf_direction dir, |
| uint8_t mask, |
| int (*fn)(struct gprs_rlcmac_pdch *, enum gprs_rlcmac_tbf_direction dir), |
| int *free_tfi = 0, int *free_usf = 0) |
| { |
| unsigned ts; |
| int min_used = INT_MAX; |
| int min_ts = -1; |
| int min_tfi = -1; |
| int min_usf = -1; |
| |
| for (ts = 0; ts < ARRAY_SIZE(trx->pdch); ts++) { |
| struct gprs_rlcmac_pdch *pdch = &trx->pdch[ts]; |
| int num_tbfs; |
| int usf = -1; /* must be signed */ |
| int tfi = -1; |
| |
| if (((1 << ts) & mask) == 0) |
| continue; |
| |
| num_tbfs = fn(pdch, dir); |
| |
| if (num_tbfs < min_used) { |
| /* We have found a candidate */ |
| /* Make sure that a TFI is available */ |
| if (free_tfi) { |
| tfi = find_free_tfi(pdch, dir); |
| if (tfi < 0) { |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Skipping TS %d, because " |
| "no TFI available\n", ts); |
| continue; |
| } |
| } |
| /* Make sure that an USF is available */ |
| if (dir == GPRS_RLCMAC_UL_TBF) { |
| usf = find_free_usf(pdch); |
| if (usf < 0) { |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Skipping TS %d, because " |
| "no USF available\n", ts); |
| continue; |
| } |
| } |
| if (min_ts >= 0) |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Skipping TS %d, because " |
| "num TBFs %d > %d\n", |
| min_ts, min_used, num_tbfs); |
| min_used = num_tbfs; |
| min_ts = ts; |
| min_tfi = tfi; |
| min_usf = usf; |
| } else { |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Skipping TS %d, because " |
| "num TBFs %d >= %d\n", |
| ts, num_tbfs, min_used); |
| } |
| } |
| |
| if (min_ts < 0) |
| return -1; |
| |
| if (free_tfi) |
| *free_tfi = min_tfi; |
| if (free_usf) |
| *free_usf = min_usf; |
| |
| return min_ts; |
| } |
| |
| static void attach_tbf_to_pdch(struct gprs_rlcmac_pdch *pdch, |
| struct gprs_rlcmac_tbf *tbf) |
| { |
| if (tbf->pdch[pdch->ts_no]) |
| tbf->pdch[pdch->ts_no]->detach_tbf(tbf); |
| |
| tbf->pdch[pdch->ts_no] = pdch; |
| pdch->attach_tbf(tbf); |
| } |
| |
| static void assign_uplink_tbf_usf( |
| struct gprs_rlcmac_pdch *pdch, |
| struct gprs_rlcmac_ul_tbf *tbf, |
| int tfi, int8_t usf) |
| { |
| tbf->m_tfi = tfi; |
| tbf->m_usf[pdch->ts_no] = usf; |
| attach_tbf_to_pdch(pdch, tbf); |
| } |
| |
| static void assign_dlink_tbf( |
| struct gprs_rlcmac_pdch *pdch, |
| struct gprs_rlcmac_dl_tbf *tbf, |
| int tfi) |
| { |
| tbf->m_tfi = tfi; |
| attach_tbf_to_pdch(pdch, tbf); |
| } |
| |
| static int find_trx(BTS *bts, const GprsMs *ms, int use_trx) |
| { |
| unsigned trx_no; |
| unsigned ts; |
| struct gprs_rlcmac_bts *bts_data = bts->bts_data(); |
| |
| /* We must use the TRX currently actively used by an MS */ |
| if (ms && ms->current_trx()) |
| return ms->current_trx()->trx_no; |
| |
| if (use_trx >= 0 && use_trx < 8) |
| return use_trx; |
| |
| /* Find the first TRX that has a PDCH with a free UL and DL TFI */ |
| for (trx_no = 0; trx_no < ARRAY_SIZE(bts_data->trx); trx_no += 1) { |
| struct gprs_rlcmac_trx *trx = &bts_data->trx[trx_no]; |
| for (ts = 0; ts < ARRAY_SIZE(trx->pdch); ts++) { |
| struct gprs_rlcmac_pdch *pdch = &trx->pdch[ts]; |
| if (!pdch->is_enabled()) |
| continue; |
| |
| if (pdch->assigned_tfi(GPRS_RLCMAC_UL_TBF) == 0xffffffff) |
| continue; |
| |
| if (pdch->assigned_tfi(GPRS_RLCMAC_DL_TBF) == 0xffffffff) |
| continue; |
| |
| return trx_no; |
| } |
| } |
| |
| return -EBUSY; |
| } |
| |
| static struct gprs_rlcmac_pdch * find_idle_pdch(BTS *bts) |
| { |
| unsigned trx_no; |
| unsigned ts; |
| struct gprs_rlcmac_bts *bts_data = bts->bts_data(); |
| |
| /* Find the first PDCH with an unused DL TS */ |
| for (trx_no = 0; trx_no < ARRAY_SIZE(bts_data->trx); trx_no += 1) { |
| struct gprs_rlcmac_trx *trx = &bts_data->trx[trx_no]; |
| for (ts = 0; ts < ARRAY_SIZE(trx->pdch); ts++) { |
| struct gprs_rlcmac_pdch *pdch = &trx->pdch[ts]; |
| if (!pdch->is_enabled()) |
| continue; |
| |
| if (pdch->num_tbfs(GPRS_RLCMAC_DL_TBF) > PDCH_IDLE_TBF_THRESH) |
| continue; |
| |
| return pdch; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| static int tfi_find_free(BTS *bts, const GprsMs *ms, |
| enum gprs_rlcmac_tbf_direction dir, int use_trx, int *trx_no_) |
| { |
| int tfi; |
| uint8_t trx_no; |
| |
| if (use_trx == -1 && ms->current_trx()) |
| use_trx = ms->current_trx()->trx_no; |
| |
| tfi = bts->tfi_find_free(dir, &trx_no, use_trx); |
| if (tfi < 0) |
| return -EBUSY; |
| |
| if (trx_no_) |
| *trx_no_ = trx_no; |
| |
| return tfi; |
| } |
| |
| /* Slot Allocation: Algorithm A |
| * |
| * Assign single slot for uplink and downlink |
| */ |
| int alloc_algorithm_a(struct gprs_rlcmac_bts *bts, |
| GprsMs *ms_, |
| struct gprs_rlcmac_tbf *tbf_, uint32_t cust, uint8_t single, |
| int use_trx) |
| { |
| struct gprs_rlcmac_pdch *pdch; |
| int ts = -1; |
| uint8_t ul_slots, dl_slots; |
| int trx_no; |
| int tfi = -1; |
| int usf = -1; |
| int mask = 0xff; |
| const char *mask_reason = NULL; |
| const GprsMs *ms = ms_; |
| const gprs_rlcmac_tbf *tbf = tbf_; |
| gprs_rlcmac_trx *trx = ms->current_trx(); |
| |
| LOGP(DRLCMAC, LOGL_DEBUG, "Slot Allocation (Algorithm A) for class " |
| "%d\n", tbf->ms_class()); |
| |
| trx_no = find_trx(bts->bts, ms, use_trx); |
| if (trx_no < 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, |
| "- Failed to find a usable TRX (TFI exhausted)\n"); |
| return trx_no; |
| } |
| if (!trx) |
| trx = &bts->trx[trx_no]; |
| |
| dl_slots = ms->reserved_dl_slots(); |
| ul_slots = ms->reserved_ul_slots(); |
| |
| ts = ms->first_common_ts(); |
| |
| if (ts >= 0) { |
| mask_reason = "need to reuse TS"; |
| mask = 1 << ts; |
| } else if (dl_slots || ul_slots) { |
| mask_reason = "need to use a reserved common TS"; |
| mask = dl_slots & ul_slots; |
| } |
| |
| mask = find_possible_pdchs(trx, 1, mask, mask_reason); |
| if (!mask) |
| return -EINVAL; |
| |
| ts = find_least_busy_pdch(trx, tbf->direction, mask, |
| compute_usage_for_algo_a, |
| &tfi, &usf); |
| |
| if (tbf->direction == GPRS_RLCMAC_UL_TBF && usf < 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "- Failed " |
| "to allocate a TS, no USF available\n"); |
| return -EBUSY; |
| } |
| |
| if (ts < 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "- Failed " |
| "to allocate a TS, no TFI available\n"); |
| return -EBUSY; |
| } |
| |
| pdch = &trx->pdch[ts]; |
| |
| /* The allocation will be successful, so the system state and tbf_/ms_ |
| * may be modified from now on. */ |
| if (tbf->direction == GPRS_RLCMAC_UL_TBF) { |
| struct gprs_rlcmac_ul_tbf *ul_tbf = as_ul_tbf(tbf_); |
| LOGP(DRLCMAC, LOGL_DEBUG, "- Assign uplink TS=%d TFI=%d USF=%d\n", |
| ts, tfi, usf); |
| assign_uplink_tbf_usf(pdch, ul_tbf, tfi, usf); |
| } else { |
| struct gprs_rlcmac_dl_tbf *dl_tbf = as_dl_tbf(tbf_); |
| LOGP(DRLCMAC, LOGL_DEBUG, "- Assign downlink TS=%d TFI=%d\n", |
| ts, tfi); |
| assign_dlink_tbf(pdch, dl_tbf, tfi); |
| } |
| |
| tbf_->trx = trx; |
| /* the only one TS is the common TS */ |
| tbf_->first_ts = tbf_->first_common_ts = ts; |
| ms_->set_reserved_slots(trx, 1 << ts, 1 << ts); |
| |
| tbf_->upgrade_to_multislot = 0; |
| bts->bts->tbf_alloc_algo_a(); |
| return 0; |
| } |
| |
| static int find_multi_slots(struct gprs_rlcmac_bts *bts, |
| struct gprs_rlcmac_trx *trx, |
| const GprsMs *ms, uint8_t *ul_slots, uint8_t *dl_slots) |
| { |
| const struct gprs_ms_multislot_class *ms_class; |
| uint8_t Tx, Sum; /* Maximum Number of Slots: RX, Tx, Sum Rx+Tx */ |
| uint8_t Tta, Ttb, Tra, Trb; /* Minimum Number of Slots */ |
| uint8_t Type; /* Type of Mobile */ |
| int rx_window, tx_window, pdch_slots; |
| static const char *digit[10] = { "0","1","2","3","4","5","6","7","8","9" }; |
| char slot_info[9] = {0}; |
| int max_capacity; |
| uint8_t max_ul_slots; |
| uint8_t max_dl_slots; |
| unsigned max_slots; |
| |
| unsigned ul_ts, dl_ts; |
| unsigned num_tx; |
| enum {MASK_TT, MASK_TR}; |
| unsigned mask_sel; |
| |
| if (ms->ms_class() >= 32) { |
| LOGP(DRLCMAC, LOGL_ERROR, "Multislot class %d out of range.\n", |
| ms->ms_class()); |
| return -EINVAL; |
| } |
| |
| if (ms->ms_class()) { |
| ms_class = &gprs_ms_multislot_class[ms->ms_class()]; |
| LOGP(DRLCMAC, LOGL_DEBUG, "Slot Allocation (Algorithm B) for " |
| "class %d\n", ms->ms_class()); |
| } else { |
| ms_class = &gprs_ms_multislot_class[12]; |
| LOGP(DRLCMAC, LOGL_DEBUG, "Slot Allocation (Algorithm B) for " |
| "unknown class (assuming 12)\n"); |
| } |
| |
| if (ms_class->tx == MS_NA) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "Multislot class %d not " |
| "applicable.\n", ms->ms_class()); |
| return -EINVAL; |
| } |
| |
| Tx = ms_class->tx; |
| Sum = ms_class->sum; |
| Tta = ms_class->ta; |
| Ttb = ms_class->tb; |
| Tra = ms_class->ra; |
| Trb = ms_class->rb; |
| Type = ms_class->type; |
| |
| /* MS_A maps to 0 if frequency hopping is disabled */ |
| /* TODO: Set it to 1 if FH is implemented and enabled */ |
| if (Ttb == MS_A) |
| Ttb = 0; |
| if (Trb == MS_A) |
| Trb = 0; |
| |
| /* MS_A and MS_B are 0 iff FH is disabled and there is no Tx/Rx change. |
| * This is never the case with the current implementation, so 1 will |
| * always be used. */ |
| if (Ttb == MS_B) |
| Ttb = 1; |
| if (Trb == MS_C) |
| Trb = 1; |
| |
| LOGP(DRLCMAC, LOGL_DEBUG, "- Rx=%d Tx=%d Sum Rx+Tx=%s Tta=%s Ttb=%d " |
| " Tra=%d Trb=%d Type=%d\n", ms_class->rx, Tx, |
| (Sum == MS_NA) ? "N/A" : digit[Sum], |
| (Tta == MS_NA) ? "N/A" : digit[Tta], Ttb, Tra, Trb, Type); |
| |
| max_slots = OSMO_MAX(ms_class->rx, ms_class->tx); |
| |
| if (*dl_slots == 0) |
| *dl_slots = 0xff; |
| |
| if (*ul_slots == 0) |
| *ul_slots = 0xff; |
| |
| pdch_slots = find_possible_pdchs(trx, max_slots, 0xff); |
| |
| *dl_slots &= pdch_slots; |
| *ul_slots &= pdch_slots; |
| |
| LOGP(DRLCMAC, LOGL_DEBUG, "- Possible DL/UL slots: (TS=0)\"%s\"(TS=7)\n", |
| set_flag_chars(set_flag_chars(set_flag_chars(slot_info, |
| *dl_slots, 'D', '.'), |
| *ul_slots, 'U'), |
| *ul_slots & *dl_slots, 'C')); |
| |
| /* Check for each UL (TX) slot */ |
| |
| max_capacity = -1; |
| max_ul_slots = 0; |
| max_dl_slots = 0; |
| |
| /* Iterate through possible numbers of TX slots */ |
| for (num_tx = 1; num_tx <= ms_class->tx; num_tx += 1) { |
| uint16_t tx_valid_win = (1 << num_tx) - 1; |
| |
| uint8_t rx_mask[MASK_TR+1]; |
| if (ms_class->type == 1) { |
| rx_mask[MASK_TT] = (0x100 >> OSMO_MAX(Ttb, Tta)) - 1; |
| rx_mask[MASK_TT] &= ~((1 << (Trb + num_tx)) - 1); |
| rx_mask[MASK_TR] = (0x100 >> Ttb) - 1; |
| rx_mask[MASK_TR] &= |
| ~((1 << (OSMO_MAX(Trb, Tra) + num_tx)) - 1); |
| } else { |
| /* Class type 2 MS have independant RX and TX */ |
| rx_mask[MASK_TT] = 0xff; |
| rx_mask[MASK_TR] = 0xff; |
| } |
| |
| rx_mask[MASK_TT] = (rx_mask[MASK_TT] << 3) | (rx_mask[MASK_TT] >> 5); |
| rx_mask[MASK_TR] = (rx_mask[MASK_TR] << 3) | (rx_mask[MASK_TR] >> 5); |
| |
| /* Rotate group of TX slots: UUU-----, -UUU----, ..., UU-----U */ |
| for (ul_ts = 0; ul_ts < 8; ul_ts += 1, tx_valid_win <<= 1) { |
| unsigned tx_slot_count; |
| int max_rx; |
| uint16_t rx_valid_win; |
| uint32_t checked_rx[256/32] = {0}; |
| |
| /* Wrap valid window */ |
| tx_valid_win = (tx_valid_win | tx_valid_win >> 8) & 0xff; |
| |
| tx_window = tx_valid_win; |
| |
| /* Filter out unavailable slots */ |
| tx_window &= *ul_slots; |
| |
| /* Skip if the the first TS (ul_ts) is not in the set */ |
| if ((tx_window & (1 << ul_ts)) == 0) |
| continue; |
| |
| /* Skip if the the last TS (ul_ts+num_tx-1) is not in the set */ |
| if ((tx_window & (1 << ((ul_ts+num_tx-1) % 8))) == 0) |
| continue; |
| |
| tx_slot_count = pcu_bitcount(tx_window); |
| |
| max_rx = OSMO_MIN(ms_class->rx, ms_class->sum - num_tx); |
| rx_valid_win = (1 << max_rx) - 1; |
| |
| /* Rotate group of RX slots: DDD-----, -DDD----, ..., DD-----D */ |
| for (dl_ts = 0; dl_ts < 8; dl_ts += 1, rx_valid_win <<= 1) { |
| /* Wrap valid window */ |
| rx_valid_win = (rx_valid_win | rx_valid_win >> 8) & 0xff; |
| |
| /* Validate with both Tta/Ttb/Trb and Ttb/Tra/Trb */ |
| for (mask_sel = MASK_TT; mask_sel <= MASK_TR; mask_sel += 1) { |
| unsigned common_slot_count; |
| unsigned req_common_slots; |
| unsigned rx_slot_count; |
| uint16_t rx_bad; |
| uint8_t rx_good; |
| unsigned ts; |
| int capacity; |
| |
| /* Filter out bad slots */ |
| rx_bad = (uint16_t)(0xff & ~rx_mask[mask_sel]) << ul_ts; |
| rx_bad = (rx_bad | (rx_bad >> 8)) & 0xff; |
| rx_good = *dl_slots & ~rx_bad; |
| |
| /* TODO: CHECK this calculation -> separate function for unit |
| * testing */ |
| |
| rx_window = rx_good & rx_valid_win; |
| rx_slot_count = pcu_bitcount(rx_window); |
| |
| #if 0 |
| LOGP(DRLCMAC, LOGL_DEBUG, "n_tx=%d, n_rx=%d, mask_sel=%d, " |
| "tx=%02x, rx=%02x, mask=%02x, bad=%02x, good=%02x, " |
| "ul=%02x, dl=%02x\n", |
| tx_slot_count, rx_slot_count, mask_sel, |
| tx_window, rx_window, rx_mask[mask_sel], rx_bad, rx_good, |
| *ul_slots, *dl_slots); |
| #endif |
| |
| /* Check compliance with TS 45.002, table 6.4.2.2.1 */ |
| /* Whether to skip this round doesn not only depend on the bit |
| * sets but also on mask_sel. Therefore this check must be done |
| * before doing the test_and_set_bit shortcut. */ |
| if (ms_class->type == 1) { |
| unsigned slot_sum = rx_slot_count + tx_slot_count; |
| /* Assume down+up/dynamic. |
| * TODO: For ext-dynamic, down only, up only add more |
| * cases. |
| */ |
| if (slot_sum <= 6 && tx_slot_count < 3) { |
| if (mask_sel != MASK_TR) |
| /* Skip Tta */ |
| continue; |
| } else if (slot_sum > 6 && tx_slot_count < 3) { |
| if (mask_sel != MASK_TT) |
| /* Skip Tra */ |
| continue; |
| } else { |
| /* No supported row in table 6.4.2.2.1. */ |
| #ifdef ENABLE_TS_ALLOC_DEBUG |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Skipping DL/UL slots: (TS=0)\"%s\"(TS=7), " |
| "combination not supported\n", |
| set_flag_chars(set_flag_chars(set_flag_chars( |
| slot_info, |
| rx_bad, 'x', '.'), |
| rx_window, 'D'), |
| tx_window, 'U')); |
| #endif |
| continue; |
| } |
| } |
| |
| /* Avoid repeated RX combination check */ |
| if (test_and_set_bit(checked_rx, rx_window)) |
| continue; |
| |
| if (!rx_good) { |
| #ifdef ENABLE_TS_ALLOC_DEBUG |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Skipping DL/UL slots: (TS=0)\"%s\"(TS=7), " |
| "no DL slots available\n", |
| set_flag_chars(set_flag_chars(slot_info, |
| rx_bad, 'x', '.'), |
| tx_window, 'U')); |
| #endif |
| continue; |
| } |
| |
| if (!rx_window) |
| continue; |
| |
| /* Check number of common slots according to TS 54.002, 6.4.2.2 */ |
| common_slot_count = pcu_bitcount(tx_window & rx_window); |
| req_common_slots = OSMO_MIN(tx_slot_count, rx_slot_count); |
| if (ms_class->type == 1) |
| req_common_slots = OSMO_MIN(req_common_slots, 2); |
| |
| if (req_common_slots != common_slot_count) { |
| #ifdef ENABLE_TS_ALLOC_DEBUG |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Skipping DL/UL slots: (TS=0)\"%s\"(TS=7), " |
| "invalid number of common TS: %d (expected %d)\n", |
| set_flag_chars(set_flag_chars(set_flag_chars( |
| slot_info, |
| rx_bad, 'x', '.'), |
| rx_window, 'D'), |
| tx_window, 'U'), |
| common_slot_count, |
| req_common_slots); |
| #endif |
| continue; |
| } |
| |
| /* Compute capacity */ |
| capacity = 0; |
| |
| for (ts = 0; ts < ARRAY_SIZE(trx->pdch); ts++) { |
| int c; |
| struct gprs_rlcmac_pdch *pdch = &trx->pdch[ts]; |
| if (rx_window & (1 << ts)) { |
| c = 32 - pdch->num_reserved(GPRS_RLCMAC_DL_TBF); |
| c = OSMO_MAX(c, 1); |
| capacity += c; |
| } |
| /* Only consider common slots for UL */ |
| if (tx_window & rx_window & (1 << ts)) { |
| if (find_free_usf(pdch) >= 0) { |
| c = 32 - pdch->num_reserved(GPRS_RLCMAC_UL_TBF); |
| c = OSMO_MAX(c, 1); |
| capacity += c; |
| } |
| } |
| } |
| |
| #ifdef ENABLE_TS_ALLOC_DEBUG |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Considering DL/UL slots: (TS=0)\"%s\"(TS=7), " |
| "capacity = %d\n", |
| set_flag_chars(set_flag_chars(set_flag_chars(set_flag_chars( |
| slot_info, |
| rx_bad, 'x', '.'), |
| rx_window, 'D'), |
| tx_window, 'U'), |
| rx_window & tx_window, 'C'), |
| capacity); |
| #endif |
| |
| if (capacity <= max_capacity) |
| continue; |
| |
| max_capacity = capacity; |
| max_ul_slots = tx_window; |
| max_dl_slots = rx_window; |
| }}}} |
| |
| if (!max_ul_slots || !max_dl_slots) { |
| LOGP(DRLCMAC, LOGL_NOTICE, |
| "No valid UL/DL slot combination found\n"); |
| return -EINVAL; |
| } |
| |
| *ul_slots = max_ul_slots; |
| *dl_slots = max_dl_slots; |
| |
| return 0; |
| } |
| |
| /* Slot Allocation: Algorithm B |
| * |
| * Assign as many downlink slots as possible. |
| * Assign one uplink slot. (With free USF) |
| * |
| */ |
| int alloc_algorithm_b(struct gprs_rlcmac_bts *bts, |
| GprsMs *ms_, struct gprs_rlcmac_tbf *tbf_, |
| uint32_t cust, uint8_t single, int use_trx) |
| { |
| uint8_t dl_slots; |
| uint8_t ul_slots; |
| uint8_t reserved_dl_slots; |
| uint8_t reserved_ul_slots; |
| int8_t first_common_ts; |
| uint8_t slotcount = 0; |
| uint8_t avail_count = 0; |
| char slot_info[9] = {0}; |
| int ts; |
| int first_ts = -1; |
| int usf[8] = {-1, -1, -1, -1, -1, -1, -1, -1}; |
| int rc; |
| int tfi; |
| int trx_no; |
| const GprsMs *ms = ms_; |
| const gprs_rlcmac_tbf *tbf = tbf_; |
| gprs_rlcmac_trx *trx; |
| |
| /* Step 1: Get current state from the MS object */ |
| |
| if (!ms) { |
| LOGP(DRLCMAC, LOGL_ERROR, "MS not set\n"); |
| return -EINVAL; |
| } |
| |
| reserved_dl_slots = dl_slots = ms->reserved_dl_slots(); |
| reserved_ul_slots = ul_slots = ms->reserved_ul_slots(); |
| first_common_ts = ms->first_common_ts(); |
| trx = ms->current_trx(); |
| |
| if (trx) { |
| if (use_trx >= 0 && use_trx != trx->trx_no) { |
| LOGP(DRLCMAC, LOGL_ERROR, |
| "- Requested incompatible TRX %d (current is %d)\n", |
| use_trx, trx->trx_no); |
| return -EINVAL; |
| } |
| use_trx = trx->trx_no; |
| } |
| |
| /* Step 2a: Find usable TRX and TFI */ |
| tfi = tfi_find_free(bts->bts, ms, tbf->direction, use_trx, &trx_no); |
| if (tfi < 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "- Failed to allocate a TFI\n"); |
| return tfi; |
| } |
| |
| /* Step 2b: Reserve slots on the TRX for the MS */ |
| if (!trx) |
| trx = &bts->trx[trx_no]; |
| |
| if (!dl_slots || !ul_slots) { |
| rc = find_multi_slots(bts, trx, ms, &ul_slots, &dl_slots); |
| if (rc < 0) |
| return rc; |
| |
| reserved_dl_slots = dl_slots; |
| reserved_ul_slots = ul_slots; |
| } |
| |
| /* Step 3: Derive the slot set for the current TBF */ |
| if (single) { |
| /* Make sure to consider the first common slot only */ |
| ul_slots = dl_slots = dl_slots & ul_slots; |
| |
| ts = first_common_ts; |
| |
| if (ts < 0) |
| ts = find_least_busy_pdch(trx, tbf->direction, |
| dl_slots & ul_slots, compute_usage_by_num_tbfs, |
| NULL, NULL); |
| if (ts < 0) |
| ul_slots = dl_slots = pcu_lsb(dl_slots & ul_slots); |
| else |
| ul_slots = dl_slots = (dl_slots & ul_slots) & (1<<ts); |
| } |
| |
| if (dl_slots == 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "No downlink slots available\n"); |
| return -EINVAL; |
| } |
| |
| if (ul_slots == 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "No uplink slots available\n"); |
| return -EINVAL; |
| } |
| |
| if (tbf->direction == GPRS_RLCMAC_DL_TBF) { |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Selected DL slots: (TS=0)\"%s\"(TS=7)%s\n", |
| set_flag_chars(set_flag_chars(slot_info, |
| reserved_dl_slots, 'd', '.'), |
| dl_slots, 'D'), |
| single ? ", single" : ""); |
| |
| /* assign downlink */ |
| if (dl_slots == 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "No downlink slots " |
| "available\n"); |
| return -EINVAL; |
| } |
| slotcount = pcu_bitcount(dl_slots); |
| first_ts = ffs(dl_slots) - 1; |
| avail_count = pcu_bitcount(reserved_dl_slots); |
| |
| } else { |
| int free_usf = -1; |
| |
| if (first_common_ts >= 0) |
| ul_slots = 1 << first_common_ts; |
| else |
| ul_slots = ul_slots & dl_slots; |
| |
| ts = find_least_busy_pdch(trx, GPRS_RLCMAC_UL_TBF, |
| ul_slots, compute_usage_by_num_tbfs, |
| NULL, &free_usf); |
| |
| if (free_usf < 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "No USF available\n"); |
| return -EBUSY; |
| } |
| OSMO_ASSERT(ts >= 0 && ts <= 8); |
| |
| ul_slots = 1 << ts; |
| usf[ts] = free_usf; |
| |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Selected UL slots: (TS=0)\"%s\"(TS=7)%s\n", |
| set_flag_chars(set_flag_chars(slot_info, |
| reserved_ul_slots, 'u', '.'), |
| ul_slots, 'U'), |
| single ? ", single" : ""); |
| |
| slotcount++; |
| first_ts = ts; |
| |
| /* We will stick to that single UL slot, unreserve the others */ |
| reserved_ul_slots = ul_slots; |
| |
| avail_count = pcu_bitcount(reserved_ul_slots); |
| } |
| |
| first_common_ts = ffs(dl_slots & ul_slots) - 1; |
| |
| if (first_common_ts < 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "No first common slots available\n"); |
| return -EINVAL; |
| } |
| if (first_ts < 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "No first slot available\n"); |
| return -EINVAL; |
| } |
| |
| if (single && slotcount) { |
| tbf_->upgrade_to_multislot = (avail_count > slotcount); |
| LOGP(DRLCMAC, LOGL_INFO, "Using single slot at TS %d for %s\n", |
| first_ts, |
| (tbf->direction == GPRS_RLCMAC_DL_TBF) ? "DL" : "UL"); |
| } else { |
| tbf_->upgrade_to_multislot = 0; |
| LOGP(DRLCMAC, LOGL_INFO, "Using %d slots for %s\n", slotcount, |
| (tbf->direction == GPRS_RLCMAC_DL_TBF) ? "DL" : "UL"); |
| } |
| |
| /* The allocation will be successful, so the system state and tbf_/ms_ |
| * may be modified from now on. */ |
| |
| /* Step 4: Update MS and TBF and really allocate the resources */ |
| |
| /* The reserved slots have changed, update the MS */ |
| if (reserved_ul_slots != ms->reserved_ul_slots() || |
| reserved_dl_slots != ms->reserved_dl_slots()) |
| { |
| ms_->set_reserved_slots(trx, |
| reserved_ul_slots, reserved_dl_slots); |
| |
| LOGP(DRLCMAC, LOGL_DEBUG, |
| "- Reserved DL/UL slots: (TS=0)\"%s\"(TS=7)\n", |
| set_flag_chars(set_flag_chars(set_flag_chars(slot_info, |
| dl_slots, 'D', '.'), |
| ul_slots, 'U'), |
| ul_slots & dl_slots, 'C')); |
| } |
| |
| tbf_->trx = trx; |
| tbf_->first_common_ts = first_common_ts; |
| tbf_->first_ts = first_ts; |
| |
| if (tbf->direction == GPRS_RLCMAC_DL_TBF) { |
| struct gprs_rlcmac_dl_tbf *dl_tbf = as_dl_tbf(tbf_); |
| for (ts = 0; ts < 8; ts++) { |
| if (!(dl_slots & (1 << ts))) |
| continue; |
| |
| LOGP(DRLCMAC, LOGL_DEBUG, "- Assigning DL TS " |
| "%d\n", ts); |
| assign_dlink_tbf(&trx->pdch[ts], dl_tbf, tfi); |
| } |
| } else { |
| struct gprs_rlcmac_ul_tbf *ul_tbf = as_ul_tbf(tbf_); |
| |
| for (ts = 0; ts < 8; ts++) { |
| if (!(ul_slots & (1 << ts))) |
| continue; |
| |
| OSMO_ASSERT(usf[ts] >= 0); |
| |
| LOGP(DRLCMAC, LOGL_DEBUG, "- Assigning UL TS " |
| "%d\n", ts); |
| assign_uplink_tbf_usf(&trx->pdch[ts], ul_tbf, |
| tfi, usf[ts]); |
| } |
| } |
| |
| bts->bts->tbf_alloc_algo_b(); |
| |
| return 0; |
| } |
| |
| /* Slot Allocation: Algorithm dynamic |
| * |
| * This meta algorithm automatically selects on of the other algorithms based |
| * on the current system state. |
| * |
| * The goal is to support as many MS and TBF as possible. On low usage, the |
| * goal is to provide the highest possible bandwidth per MS. |
| * |
| */ |
| int alloc_algorithm_dynamic(struct gprs_rlcmac_bts *bts, |
| GprsMs *ms_, struct gprs_rlcmac_tbf *tbf_, |
| uint32_t cust, uint8_t single, int use_trx) |
| { |
| int rc; |
| |
| /* Reset load_is_high if there is at least one idle PDCH */ |
| if (bts->multislot_disabled) { |
| bts->multislot_disabled = find_idle_pdch(bts->bts) == NULL; |
| if (!bts->multislot_disabled) |
| LOGP(DRLCMAC, LOGL_DEBUG, "Enabling algorithm B\n"); |
| } |
| |
| if (!bts->multislot_disabled) { |
| rc = alloc_algorithm_b(bts, ms_, tbf_, cust, single, use_trx); |
| if (rc >= 0) |
| return rc; |
| |
| if (!bts->multislot_disabled) |
| LOGP(DRLCMAC, LOGL_DEBUG, "Disabling algorithm B\n"); |
| bts->multislot_disabled = 1; |
| } |
| |
| rc = alloc_algorithm_a(bts, ms_, tbf_, cust, single, use_trx); |
| return rc; |
| } |
| |
| int gprs_alloc_max_dl_slots_per_ms(struct gprs_rlcmac_bts *bts, uint8_t ms_class) |
| { |
| int rx; |
| |
| if (ms_class >= ARRAY_SIZE(gprs_ms_multislot_class)) |
| ms_class = 0; |
| |
| rx = gprs_ms_multislot_class[ms_class].rx; |
| |
| if (rx == MS_NA) |
| rx = 4; |
| |
| if (bts->alloc_algorithm == alloc_algorithm_a) |
| return 1; |
| |
| if (bts->multislot_disabled) |
| return 1; |
| |
| return rx; |
| } |