[dpdk-dev] [PATCH 3/6] rte_sched: keep track of RED drops

[Stephen Hemminger <stephen@networkplumber.org>]

From: Stephen Hemminger <shemming@brocade.com>

Add new statistic to keep track of drops due to RED.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/librte_sched/rte_sched.c | 31 ++++++++++++++++++++++++++-----
 lib/librte_sched/rte_sched.h |  6 ++++++
 2 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/lib/librte_sched/rte_sched.c b/lib/librte_sched/rte_sched.c
index 3b5acd1..c044c09 100644
--- a/lib/librte_sched/rte_sched.c
+++ b/lib/librte_sched/rte_sched.c
@@ -1028,7 +1028,9 @@ rte_sched_port_update_subport_stats(struct rte_sched_port *port, uint32_t qindex
 }
 
 static inline void
-rte_sched_port_update_subport_stats_on_drop(struct rte_sched_port *port, uint32_t qindex, struct rte_mbuf *pkt)
+rte_sched_port_update_subport_stats_on_drop(struct rte_sched_port *port,
+					    uint32_t qindex,
+					    struct rte_mbuf *pkt, uint32_t red)
 {
 	struct rte_sched_subport *s = port->subport + (qindex / rte_sched_port_queues_per_subport(port));
 	uint32_t tc_index = (qindex >> 2) & 0x3;
@@ -1036,6 +1038,9 @@ rte_sched_port_update_subport_stats_on_drop(struct rte_sched_port *port, uint32_
 
 	s->stats.n_pkts_tc_dropped[tc_index] += 1;
 	s->stats.n_bytes_tc_dropped[tc_index] += pkt_len;
+#ifdef RTE_SCHED_RED
+	s->stats.n_pkts_red_dropped[tc_index] += red;
+#endif
 }
 
 static inline void
@@ -1049,13 +1054,18 @@ rte_sched_port_update_queue_stats(struct rte_sched_port *port, uint32_t qindex,
 }
 
 static inline void
-rte_sched_port_update_queue_stats_on_drop(struct rte_sched_port *port, uint32_t qindex, struct rte_mbuf *pkt)
+rte_sched_port_update_queue_stats_on_drop(struct rte_sched_port *port,
+					  uint32_t qindex,
+					  struct rte_mbuf *pkt, uint32_t red)
 {
 	struct rte_sched_queue_extra *qe = port->queue_extra + qindex;
 	uint32_t pkt_len = pkt->pkt_len;
 
 	qe->stats.n_pkts_dropped += 1;
 	qe->stats.n_bytes_dropped += pkt_len;
+#ifdef RTE_SCHED_RED
+	qe->stats.n_pkts_red_dropped += red;
+#endif
 }
 
 #endif /* RTE_SCHED_COLLECT_STATS */
@@ -1206,12 +1216,23 @@ rte_sched_port_enqueue_qwa(struct rte_sched_port *port, uint32_t qindex, struct
 	qlen = q->qw - q->qr;
 
 	/* Drop the packet (and update drop stats) when queue is full */
-	if (unlikely(rte_sched_port_red_drop(port, pkt, qindex, qlen) || (qlen >= qsize))) {
+	if (unlikely(rte_sched_port_red_drop(port, pkt, qindex, qlen))) {
+#ifdef RTE_SCHED_COLLECT_STATS
+		rte_sched_port_update_subport_stats_on_drop(port, qindex,
+							    pkt, 1);
+		rte_sched_port_update_queue_stats_on_drop(port, qindex, pkt, 1);
+#endif
 		rte_pktmbuf_free(pkt);
+		return 0;
+	}
+
+	if (qlen >= qsize) {
 #ifdef RTE_SCHED_COLLECT_STATS
-		rte_sched_port_update_subport_stats_on_drop(port, qindex, pkt);
-		rte_sched_port_update_queue_stats_on_drop(port, qindex, pkt);
+		rte_sched_port_update_subport_stats_on_drop(port, qindex,
+							    pkt, 0);
+		rte_sched_port_update_queue_stats_on_drop(port, qindex, pkt, 0);
 #endif
+		rte_pktmbuf_free(pkt);
 		return 0;
 	}
 
diff --git a/lib/librte_sched/rte_sched.h b/lib/librte_sched/rte_sched.h
index bf5ef8d..3fd1fe1 100644
--- a/lib/librte_sched/rte_sched.h
+++ b/lib/librte_sched/rte_sched.h
@@ -140,6 +140,9 @@ struct rte_sched_subport_stats {
 	                                      subport for each traffic class*/
 	uint32_t n_bytes_tc_dropped[RTE_SCHED_TRAFFIC_CLASSES_PER_PIPE]; /**< Number of bytes dropped by the current
                                           subport for each traffic class due to subport queues being full or congested */
+#ifdef RTE_SCHED_RED
+	uint32_t n_pkts_red_dropped[RTE_SCHED_TRAFFIC_CLASSES_PER_PIPE]; /**< Number of packets dropped by red */
+#endif
 };
 
 /** Pipe configuration parameters. The period and credits_per_period parameters are measured
@@ -168,6 +171,9 @@ struct rte_sched_queue_stats {
 	/* Packets */
 	uint32_t n_pkts;                 /**< Number of packets successfully written to current queue */
 	uint32_t n_pkts_dropped;         /**< Number of packets dropped due to current queue being full or congested */
+#ifdef RTE_SCHED_RED
+	uint32_t n_pkts_red_dropped;
+#endif
 
 	/* Bytes */
 	uint32_t n_bytes;                /**< Number of bytes successfully written to current queue */
-- 
2.1.4