From f22ae5af5f2df0e2e643c50f51978a4ca96d618a Mon Sep 17 00:00:00 2001
From: Harald Welte <laforge@osmocom.org>
Date: Sat, 30 Jan 2021 22:01:28 +0100
Subject: [PATCH] ns2: count number of dropped packets / bytes on transmit

Differentiate between successfully transmitted packets/bytes,
and pacets/bytes that were dropped (i.e. overflow of net-device)

OsmoNSdummy# show ns nsvc 1001 stats
 NSVCI 01001: UNBLOCKED PERSIST data_weight=1 sig_weight=1 fr)netif: hdlc1 dlci: 1001
  NSVC Peer Statistics:
   Packets at NS Level  ( In):       36 (0/s 8/m 32/h 0/d)
   Packets at NS Level  (Out):    23344 (170/s 20556/m 13119/h 0/d)
   Dropped Packets      (Out):    30692 (230/s 27056/m 17221/h 0/d)
   Bytes at NS Level    ( In):      262 (0/s 24/m 250/h 0/d)
   Bytes at NS Level    (Out): 32741312 (238680/s 28849400/m 18391024/h 0/d)
   Dropped Bytes        (Out): 43014628 (322920/s 37986624/m 24101344/h 0/d)

Change-Id: If21906ff5379038f7be10cf48c68d1f756dd7c1e
---
 src/gb/gprs_ns2.c          |  2 ++
 src/gb/gprs_ns2_internal.h |  2 ++
 src/gb/gprs_ns2_message.c  | 16 +++++++++++++---
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/gb/gprs_ns2.c b/src/gb/gprs_ns2.c
index d3c1e6990..0f65d37e7 100644
--- a/src/gb/gprs_ns2.c
+++ b/src/gb/gprs_ns2.c
@@ -162,8 +162,10 @@ const struct value_string gprs_ns2_cause_strs[] = {
 static const struct rate_ctr_desc nsvc_ctr_description[] = {
 	[NS_CTR_PKTS_IN]	= { "packets:in", 	"Packets at NS Level  ( In)" },
 	[NS_CTR_PKTS_OUT] 	= { "packets:out",	"Packets at NS Level  (Out)" },
+	[NS_CTR_PKTS_OUT_DROP] 	= { "packets:out:drop",	"Dropped Packets      (Out)" },
 	[NS_CTR_BYTES_IN]	= { "bytes:in",		"Bytes at NS Level    ( In)" },
 	[NS_CTR_BYTES_OUT]	= { "bytes:out",	"Bytes at NS Level    (Out)" },
+	[NS_CTR_BYTES_OUT_DROP]	= { "bytes:out:drop",	"Dropped Bytes        (Out)" },
 	[NS_CTR_BLOCKED]	= { "blocked",		"NS-VC Block count         " },
 	[NS_CTR_DEAD] 		= { "dead",		"NS-VC gone dead count     " },
 	[NS_CTR_REPLACED]	= { "replaced",		"NS-VC replaced other count" },
diff --git a/src/gb/gprs_ns2_internal.h b/src/gb/gprs_ns2_internal.h
index 68f28dbaa..98b3f2941 100644
--- a/src/gb/gprs_ns2_internal.h
+++ b/src/gb/gprs_ns2_internal.h
@@ -88,8 +88,10 @@ enum ns2_cs {
 enum ns_ctr {
 	NS_CTR_PKTS_IN,
 	NS_CTR_PKTS_OUT,
+	NS_CTR_PKTS_OUT_DROP,
 	NS_CTR_BYTES_IN,
 	NS_CTR_BYTES_OUT,
+	NS_CTR_BYTES_OUT_DROP,
 	NS_CTR_BLOCKED,
 	NS_CTR_DEAD,
 	NS_CTR_REPLACED,
diff --git a/src/gb/gprs_ns2_message.c b/src/gb/gprs_ns2_message.c
index cd498969b..bfb8781d6 100644
--- a/src/gb/gprs_ns2_message.c
+++ b/src/gb/gprs_ns2_message.c
@@ -168,10 +168,20 @@ int ns2_validate(struct gprs_ns2_vc *nsvc,
 
 static int ns_vc_tx(struct gprs_ns2_vc *nsvc, struct msgb *msg)
 {
-	rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_PKTS_OUT]);
-	rate_ctr_add(&nsvc->ctrg->ctr[NS_CTR_BYTES_OUT], msgb_length(msg));
+	unsigned int bytes = msgb_length(msg);
+	int rc;
 
-	return nsvc->bind->send_vc(nsvc, msg);
+
+	rc = nsvc->bind->send_vc(nsvc, msg);
+	if (rc < 0) {
+		rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_PKTS_OUT_DROP]);
+		rate_ctr_add(&nsvc->ctrg->ctr[NS_CTR_BYTES_OUT_DROP], bytes);
+	} else {
+		rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_PKTS_OUT]);
+		rate_ctr_add(&nsvc->ctrg->ctr[NS_CTR_BYTES_OUT], bytes);
+	}
+
+	return rc;
 }
 
 /* transmit functions */