alloc: Optionally enforce first common TS in find_multi_slots (TODO)

TODO:

- This isn't probably triggered at all currently, so this commit
  can possibly be dropped

src/gprs_bssgp_pcu.cpp

@@ -586,6 +586,23 @@ static uint32_t get_and_reset_avg_queue_delay(void)
 	return avg_delay_ms;
 }
 
+static int get_and_reset_measured_leak_rate(int num_pdch)
+{
+	int rate; /* byte per second */
+
+	if (the_pcu.queue_frames_sent == 0)
+		return -1;
+
+	/* 20ms/num_pdch is the average RLC block duration */
+	rate = the_pcu.queue_bytes_recv * 1000 * num_pdch /
+		(20 * the_pcu.queue_frames_sent);
+
+	the_pcu.queue_frames_sent = 0;
+	the_pcu.queue_bytes_recv = 0;
+
+	return rate;
+}
+
 int gprs_bssgp_tx_fc_bvc(void)
 {
 	struct gprs_rlcmac_bts *bts;
@@ -624,6 +641,20 @@ int gprs_bssgp_tx_fc_bvc(void)
 	ms_bucket_size = bts->fc_ms_bucket_size;
 	ms_leak_rate = bts->fc_ms_leak_rate;
 
+	if (leak_rate == 0) {
+		int meas_rate;
+
+		if (num_pdch < 0)
+			num_pdch = count_pdch(bts);
+
+		meas_rate = get_and_reset_measured_leak_rate(num_pdch);
+		if (meas_rate > 0) {
+			leak_rate = meas_rate;
+			LOGP(DBSSGP, LOGL_DEBUG,
+				"Measured BVC leak rate = %d\n", leak_rate);
+		}
+	}
+
 	if (leak_rate == 0) {
 		if (num_pdch < 0)
 			num_pdch = count_pdch(bts);
@@ -823,6 +854,16 @@ struct bssgp_bvc_ctx *gprs_bssgp_pcu_current_bctx(void)
 	return the_pcu.bctx;
 }
 
+void gprs_bssgp_update_frames_sent()
+{
+	the_pcu.queue_frames_sent += 1;
+}
+
+void gprs_bssgp_update_bytes_received(unsigned bytes_recv)
+{
+	the_pcu.queue_bytes_recv += bytes_recv;
+}
+
 void gprs_bssgp_update_queue_delay(const struct timeval *tv_recv,
 	const struct timeval *tv_now)
 {

src/gprs_bssgp_pcu.h

@@ -62,6 +62,8 @@ struct gprs_bssgp_pcu {
 	struct timeval queue_delay_sum;
 	unsigned queue_delay_count;
 	uint8_t fc_tag;
+	unsigned queue_frames_sent;
+	unsigned queue_bytes_recv;
 
 	/** callbacks below */
 
@@ -85,5 +87,7 @@ struct bssgp_bvc_ctx *gprs_bssgp_pcu_current_bctx(void);
 
 void gprs_bssgp_update_queue_delay(const struct timeval *tv_recv,
 		const struct timeval *tv_now);
+void gprs_bssgp_update_frames_sent();
+void gprs_bssgp_update_bytes_received(unsigned bytes_recv);
 
 #endif // GPRS_BSSGP_PCU_H

src/gprs_rlcmac_sched.cpp

@@ -321,6 +321,10 @@ int gprs_rlcmac_rcv_rts_block(struct gprs_rlcmac_bts *bts,
 	if (!msg)
 		msg = sched_select_downlink(bts, trx, ts, fn, block_nr, pdch);
 
+	/* Used to calculate the net leak rate, must not include dummy messages */
+	if (msg)
+		gprs_bssgp_update_frames_sent();
+
 	/* Prio 3: send dummy contol message */
 	if (!msg)
 		msg = sched_dummy();

src/gprs_rlcmac_ts_alloc.cpp

@@ -505,7 +505,8 @@ int alloc_algorithm_a(struct gprs_rlcmac_bts *bts,
 
 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 GprsMs *ms, uint8_t *ul_slots, uint8_t *dl_slots,
+	int first_common_ts)
 {
 	const struct gprs_ms_multislot_class *ms_class;
 	uint8_t Tx, Sum;	/* Maximum Number of Slots: RX, Tx, Sum Rx+Tx */
@@ -523,6 +524,8 @@ static int find_multi_slots(struct gprs_rlcmac_bts *bts,
 	unsigned num_tx;
 	enum {MASK_TT, MASK_TR};
 	unsigned mask_sel;
+	uint8_t common_mask = 0;
+	uint8_t common_req = 0;
 
 	if (ms->ms_class() >= 32) {
 		LOGP(DRLCMAC, LOGL_ERROR, "Multislot class %d out of range.\n",
@@ -599,6 +602,11 @@ static int find_multi_slots(struct gprs_rlcmac_bts *bts,
 	max_ul_slots = 0;
 	max_dl_slots = 0;
 
+	if (first_common_ts >= 0) {
+		common_req = 1 << first_common_ts;
+		common_mask = (common_req << 1) - 1;
+	}
+
 	/* 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;
@@ -735,6 +743,15 @@ static int find_multi_slots(struct gprs_rlcmac_bts *bts,
 		if (!rx_window)
 			continue;
 
+		/* Check required common slots */
+		if (((tx_window & rx_window) & common_mask) != common_req) {
+			LOGP(DRLCMAC, LOGL_INFO,
+				"Common slot pre-selection mismatch: "
+				"%02x %02x %02x %02x\n",
+				tx_window, rx_window, common_mask, common_req);
+			continue;
+		}
+
 		/* Check number of common slots according to TS 54.002, 6.4.2.2 */
 		common_slot_count = bitcount(tx_window & rx_window);
 		req_common_slots = OSMO_MIN(tx_slot_count, rx_slot_count);
@@ -873,7 +890,8 @@ int alloc_algorithm_b(struct gprs_rlcmac_bts *bts,
 		trx = &bts->trx[trx_no];
 
 	if (!dl_slots || !ul_slots) {
-		rc = find_multi_slots(bts, trx, ms, &ul_slots, &dl_slots);
+		rc = find_multi_slots(bts, trx, ms, &ul_slots, &dl_slots,
+			first_common_ts);
 		if (rc < 0)
 			return rc;
 

src/tbf.h

@@ -355,6 +355,13 @@ struct gprs_rlcmac_dl_tbf : public gprs_rlcmac_tbf {
 	} m_bw;
 
 protected:
+	struct ana_result {
+		unsigned received_packets;
+		unsigned lost_packets;
+		unsigned received_bytes;
+		unsigned lost_bytes;
+	};
+
 	struct msgb *create_new_bsn(const uint32_t fn, const uint8_t ts);
 	struct msgb *create_dl_acked_block(const uint32_t fn, const uint8_t ts,
 					const int index);
@@ -363,7 +370,7 @@ protected:
 	bool dl_window_stalled() const;
 	void reuse_tbf();
 	void start_llc_timer();
-	int analyse_errors(char *show_rbb, uint8_t ssn);
+	int analyse_errors(char *show_rbb, uint8_t ssn, ana_result *res);
 	void schedule_next_frame();
 
 	struct osmo_timer_list m_llc_timer;

src/tbf_dl.cpp

@@ -689,7 +689,8 @@ static uint16_t bitnum_to_bsn(int bitnum, uint16_t ssn, uint16_t mod_sns)
 	return (ssn - 1 - bitnum) & mod_sns;
 }
 
-int gprs_rlcmac_dl_tbf::analyse_errors(char *show_rbb, uint8_t ssn)
+int gprs_rlcmac_dl_tbf::analyse_errors(char *show_rbb, uint8_t ssn,
+	ana_result *res)
 {
 	gprs_rlc_data *rlc_data;
 	uint16_t lost = 0, received = 0, skipped = 0;
@@ -697,9 +698,13 @@ int gprs_rlcmac_dl_tbf::analyse_errors(char *show_rbb, uint8_t ssn)
 	memset(info, '.', sizeof(info));
 	info[64] = 0;
 	uint16_t bsn = 0;
+	unsigned received_bytes = 0, lost_bytes = 0;
+	unsigned received_packets = 0, lost_packets = 0;
 
 	/* SSN - 1 is in range V(A)..V(S)-1 */
 	for (int bitpos = 0; bitpos < m_window.ws(); bitpos++) {
+		bool is_received = show_rbb[m_window.ws() - 1 - bitpos] == 'R';
+
 		bsn = bitnum_to_bsn(bitpos, ssn, m_window.mod_sns());
 
 		if (bsn == ((m_window.v_a() - 1) & m_window.mod_sns())) {
@@ -713,6 +718,17 @@ int gprs_rlcmac_dl_tbf::analyse_errors(char *show_rbb, uint8_t ssn)
 			continue;
 		}
 
+		/* Get general statistics */
+		if (is_received && !m_window.m_v_b.is_acked(bsn)) {
+			received_packets += 1;
+			received_bytes += rlc_data->len;
+		} else if (!is_received) {
+			lost_packets += 1;
+			lost_bytes += rlc_data->len;
+		}
+
+		/* Get statistics for current CS */
+
 		if (rlc_data->cs != current_cs()) {
 			/* This block has already been encoded with a different
 			 * CS, so it doesn't help us to decide, whether the
@@ -722,7 +738,7 @@ int gprs_rlcmac_dl_tbf::analyse_errors(char *show_rbb, uint8_t ssn)
 			continue;
 		}
 
-		if (show_rbb[m_window.ws() - 1 - bitpos] == 'R') {
+		if (is_received) {
 			if (!m_window.m_v_b.is_acked(bsn)) {
 				received += 1;
 				info[bitpos] = 'R';
@@ -740,6 +756,11 @@ int gprs_rlcmac_dl_tbf::analyse_errors(char *show_rbb, uint8_t ssn)
 		name(), m_window.v_a(), m_window.v_s(), lost, received,
 		skipped, bsn, info);
 
+	res->received_packets = received_packets;
+	res->lost_packets = lost_packets;
+	res->received_bytes = received_bytes;
+	res->lost_bytes = lost_bytes;
+
 	if (lost + received <= 1)
 		return -1;
 
@@ -755,6 +776,7 @@ int gprs_rlcmac_dl_tbf::update_window(const uint8_t ssn, const uint8_t *rbb)
 	char show_v_b[RLC_MAX_SNS + 1];
 	const uint16_t mod_sns = m_window.mod_sns();
 	int error_rate;
+	struct ana_result ana_res;
 
 	Decoding::extract_rbb(rbb, show_rbb);
 	/* show received array in debug (bit 64..1) */
@@ -777,10 +799,10 @@ int gprs_rlcmac_dl_tbf::update_window(const uint8_t ssn, const uint8_t *rbb)
 		return 1; /* indicate to free TBF */
 	}
 
-	if (bts_data()->cs_adj_enabled && ms()) {
-		error_rate = analyse_errors(show_rbb, ssn);
+	error_rate = analyse_errors(show_rbb, ssn, &ana_res);
+
+	if (bts_data()->cs_adj_enabled && ms())
 		ms()->update_error_rate(this, error_rate);
-	}
 
 	m_window.update(bts, show_rbb, ssn,
 			&lost, &received);
@@ -788,6 +810,9 @@ int gprs_rlcmac_dl_tbf::update_window(const uint8_t ssn, const uint8_t *rbb)
 	/* report lost and received packets */
 	gprs_rlcmac_received_lost(this, received, lost);
 
+	/* Used to calculate the net leak rate */
+	gprs_bssgp_update_bytes_received(ana_res.received_bytes);
+
 	/* raise V(A), if possible */
 	m_window.raise(m_window.move_window());