Add stat items for the BTS's channel load average and T3122.

In addition to logging the current values of a BTS's channel load
average and T3122 override, maintain stat items for these values.
This allows for plotting these values over time, for instance.

These values show up in the VTY under 'show stats' like this:

base transceiver station:
 Channel load average.:       25 %
 T3122 IMMEDIATE ASSIGNMENT REJECT wait indicator.: 32 s

Change-Id: Icace0176e8b1d23d7c7b4816f7c67c65312844fa
Suggested-by: laforge

4 files changed, 28 insertions, 2 deletions

diff --git a/include/osmocom/bsc/gsm_data.h b/include/osmocom/bsc/gsm_data.h
index 25dee7876..9a35ca945 100644
--- a/include/osmocom/bsc/gsm_data.h
+++ b/include/osmocom/bsc/gsm_data.h
@@ -10,6 +10,7 @@
 #include <osmocom/core/rate_ctr.h>
 #include <osmocom/core/select.h>
 #include <osmocom/core/stats.h>
+#include <osmocom/core/stat_item.h>
 
 #include <osmocom/crypt/auth.h>
 
@@ -177,6 +178,11 @@ static const struct rate_ctr_group_desc bts_ctrg_desc = {
 };
 
 enum {
+	BTS_STAT_CHAN_LOAD_AVERAGE,
+	BTS_STAT_T3122,
+};
+
+enum {
 	BSC_CTR_HANDOVER_ATTEMPTED,
 	BSC_CTR_HANDOVER_NO_CHANNEL,
 	BSC_CTR_HANDOVER_TIMEOUT,
diff --git a/include/osmocom/bsc/gsm_data_shared.h b/include/osmocom/bsc/gsm_data_shared.h
index 7a650fe2b..e3e138957 100644
--- a/include/osmocom/bsc/gsm_data_shared.h
+++ b/include/osmocom/bsc/gsm_data_shared.h
@@ -805,6 +805,7 @@ struct gsm_bts {
 	struct pcu_sock_state *pcu_state;
 
 	struct rate_ctr_group *bts_ctrs;
+	struct osmo_stat_item_group *bts_statg;
 
 	struct handover_cfg *ho;
 
diff --git a/src/libbsc/chan_alloc.c b/src/libbsc/chan_alloc.c
index 5e2c0ee22..500ad5958 100644
--- a/src/libbsc/chan_alloc.c
+++ b/src/libbsc/chan_alloc.c
@@ -656,6 +656,8 @@ bts_update_t3122_chan_load(struct gsm_bts *bts)
 	load = ((used / total) * 100);
 	LOGP(DRLL, LOGL_DEBUG, "(bts=%d) channel load average is %lu.%.2lu%%\n",
 	     bts->nr, (load & 0xffffff00) >> 8, (load & 0xff) / 10);
+	osmo_stat_item_set(bts->bts_statg->items[BTS_STAT_CHAN_LOAD_AVERAGE],
+			   (load & 0xffffff00) >> 8);
 
 	/* Calculate new T3122 wait indicator. */
 	wait_ind = ((used / total) * max_wait_ind);
@@ -667,4 +669,5 @@ bts_update_t3122_chan_load(struct gsm_bts *bts)
 
 	LOGP(DRLL, LOGL_DEBUG, "(bts=%d) T3122 wait indicator set to %lu seconds\n", bts->nr, wait_ind);
 	bts->T3122 = (uint8_t)wait_ind;
+	osmo_stat_item_set(bts->bts_statg->items[BTS_STAT_T3122], wait_ind);
 }
diff --git a/src/libcommon/gsm_data_shared.c b/src/libcommon/gsm_data_shared.c
index 3afc67ebc..57bf77d06 100644
--- a/src/libcommon/gsm_data_shared.c
+++ b/src/libcommon/gsm_data_shared.c
@@ -30,11 +30,25 @@
 #include <osmocom/core/talloc.h>
 #include <osmocom/gsm/gsm_utils.h>
 #include <osmocom/gsm/abis_nm.h>
-#include <osmocom/core/statistics.h>
+#include <osmocom/core/counter.h>
+#include <osmocom/core/stats.h>
 
 #include <osmocom/bsc/gsm_data.h>
 #include <osmocom/bsc/handover_cfg.h>
 
+static const struct osmo_stat_item_desc bts_stat_desc[] = {
+	{ "chanloadavg", "Channel load average.", "%", 16, 0 },
+	{ "T3122", "T3122 IMMEDIATE ASSIGNMENT REJECT wait indicator.", "s", 16, GSM_T3122_DEFAULT },
+};
+
+static const struct osmo_stat_item_group_desc bts_statg_desc = {
+	.group_name_prefix = "bts",
+	.group_description = "base transceiver station",
+	.class_id = OSMO_STATS_CLASS_GLOBAL,
+	.num_items = ARRAY_SIZE(bts_stat_desc),
+	.item_desc = bts_stat_desc,
+};
+
 void gsm_abis_mo_reset(struct gsm_abis_mo *mo)
 {
 	mo->nm_state.operational = NM_OPSTATE_NULL;
@@ -353,11 +367,13 @@ struct gsm_bts *gsm_bts_alloc(struct gsm_network *net, uint8_t bts_num)
 		talloc_free(bts);
 		return NULL;
 	}
+	bts->bts_statg = osmo_stat_item_group_alloc(bts, &bts_statg_desc, 0);
 
 	/* create our primary TRX */
 	bts->c0 = gsm_bts_trx_alloc(bts);
 	if (!bts->c0) {
-		talloc_free(bts->bts_ctrs);
+		rate_ctr_group_free(bts->bts_ctrs);
+		osmo_stat_item_group_free(bts->bts_statg);
 		talloc_free(bts);
 		return NULL;
 	}