tbf: Maintain the number of TBF per PDCH

Currently the PDCH object do not know anything about the TBFs using
them. To make the slot allocation load dependant, at least some
numbers are required.

This commit adds TBF counters (one per direction) and the related methods
attach_tbf, detach_tbf, and num_tbfs to gprs_rlcmac_pdch.

Sponsored-by: On-Waves ehf

4 files changed, 49 insertions, 8 deletions

diff --git a/src/bts.cpp b/src/bts.cpp
index bc5ac945..6da8cdd8 100644
--- a/src/bts.cpp
+++ b/src/bts.cpp
@@ -1131,3 +1131,19 @@ gprs_rlcmac_dl_tbf *gprs_rlcmac_pdch::dl_tbf_by_tfi(uint8_t tfi)
 {
 	return static_cast<gprs_rlcmac_dl_tbf *>(tbf_from_list_by_tfi(&bts_data()->dl_tbfs, tfi, GPRS_RLCMAC_DL_TBF));
 }
+
+void gprs_rlcmac_pdch::attach_tbf(gprs_rlcmac_tbf *tbf)
+{
+	m_num_tbfs[tbf->direction] += 1;
+	LOGP(DRLCMAC, LOGL_INFO, "PDCH(TS %d, TRX %d): Attaching %s, %d TBFs.\n",
+		ts_no, trx_no(), tbf->name(), m_num_tbfs[tbf->direction]);
+}
+
+void gprs_rlcmac_pdch::detach_tbf(gprs_rlcmac_tbf *tbf)
+{
+	OSMO_ASSERT(m_num_tbfs[tbf->direction] > 0);
+
+	m_num_tbfs[tbf->direction] -= 1;
+	LOGP(DRLCMAC, LOGL_INFO, "PDCH(TS %d, TRX %d): Detaching %s, %d TBFs.\n",
+		ts_no, trx_no(), tbf->name(), m_num_tbfs[tbf->direction]);
+}
diff --git a/src/bts.h b/src/bts.h
index 7e34db5f..f6cc88fa 100644
--- a/src/bts.h
+++ b/src/bts.h
@@ -66,6 +66,11 @@ struct gprs_rlcmac_pdch {
 
 	struct gprs_rlcmac_ul_tbf *ul_tbf_by_tfi(uint8_t tfi);
 	struct gprs_rlcmac_dl_tbf *dl_tbf_by_tfi(uint8_t tfi);
+
+	void attach_tbf(gprs_rlcmac_tbf *tbf);
+	void detach_tbf(gprs_rlcmac_tbf *tbf);
+
+	unsigned num_tbfs(enum gprs_rlcmac_tbf_direction dir) const;
 #endif
 
 	uint8_t m_is_enabled; /* TS is enabled */
@@ -93,6 +98,8 @@ private:
 	gprs_rlcmac_tbf *tbf_from_list_by_tfi(struct llist_head *tbf_list, uint8_t tfi,
 		enum gprs_rlcmac_tbf_direction dir);
 #endif
+
+	uint8_t m_num_tbfs[2];
 };
 
 struct gprs_rlcmac_trx {
@@ -299,6 +306,11 @@ inline BTS *gprs_rlcmac_pdch::bts() const
 	return trx->bts;
 }
 
+inline unsigned gprs_rlcmac_pdch::num_tbfs(enum gprs_rlcmac_tbf_direction dir) const
+{
+	return m_num_tbfs[dir];
+}
+
 inline struct rate_ctr_group *BTS::rate_counters() const
 {
 	return m_ratectrs;
diff --git a/src/gprs_rlcmac_ts_alloc.cpp b/src/gprs_rlcmac_ts_alloc.cpp
index bae1ea5f..29749b8e 100644
--- a/src/gprs_rlcmac_ts_alloc.cpp
+++ b/src/gprs_rlcmac_ts_alloc.cpp
@@ -117,13 +117,23 @@ static int find_enabled_pdch(struct gprs_rlcmac_trx *trx, const uint8_t start_ts
 	return 8;
 }
 
+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, int8_t usf)
 {
 	tbf->trx->ul_tbf[tbf->tfi()] = tbf;
-	tbf->pdch[pdch->ts_no] = pdch;
 	tbf->m_usf[pdch->ts_no] = usf;
+	attach_tbf_to_pdch(pdch, tbf);
 }
 
 static void assign_dlink_tbf(
@@ -131,7 +141,7 @@ static void assign_dlink_tbf(
 				struct gprs_rlcmac_dl_tbf *tbf)
 {
 	tbf->trx->dl_tbf[tbf->tfi()] = tbf;
-	tbf->pdch[pdch->ts_no] = pdch;
+	attach_tbf_to_pdch(pdch, tbf);
 }
 
 
diff --git a/src/tbf.cpp b/src/tbf.cpp
index 9bdc1f78..ddc3b91f 100644
--- a/src/tbf.cpp
+++ b/src/tbf.cpp
@@ -209,14 +209,17 @@ static void tbf_unlink_pdch(struct gprs_rlcmac_tbf *tbf)
 {
 	int ts;
 
-	if (tbf->direction == GPRS_RLCMAC_UL_TBF) {
+	if (tbf->direction == GPRS_RLCMAC_UL_TBF)
 		tbf->trx->ul_tbf[tbf->tfi()] = NULL;
-		for (ts = 0; ts < 8; ts++)
-			tbf->pdch[ts] = NULL;
-	} else {
+	else
 		tbf->trx->dl_tbf[tbf->tfi()] = NULL;
-		for (ts = 0; ts < 8; ts++)
-			tbf->pdch[ts] = NULL;
+
+	for (ts = 0; ts < 8; ts++) {
+		if (!tbf->pdch[ts])
+			continue;
+
+		tbf->pdch[ts]->detach_tbf(tbf);
+		tbf->pdch[ts] = NULL;
 	}
 }