net/pcap: support imissed stats

Get value from pcap_stats.ps_drop (see man pcap_stats)
the value is adjusted in this cases:
 - port stop - pcap is closed and will lose count
 - stats reset - pcap doesn't provide reset api
 - rollover - pcap counter size is u_32 only

Signed-off-by: Ido Goshen <ido@cgstowernetworks.com>
Acked-by: Ferruh Yigit <ferruh.yigit@intel.com>

diff --git a/drivers/net/pcap/rte_eth_pcap.c b/drivers/net/pcap/rte_eth_pcap.c
index 90f5d75..38b1fe2 100644 (file)
--- a/drivers/net/pcap/rte_eth_pcap.c
+++ b/drivers/net/pcap/rte_eth_pcap.c
@@ -60,11 +60,21 @@ struct queue_stat {
        volatile unsigned long err_pkts;
 };
 
+struct queue_missed_stat {
+       /* last value retrieved from pcap */
+       unsigned int pcap;
+       /* stores values lost by pcap stop or rollover */
+       unsigned long mnemonic;
+       /* value on last reset */
+       unsigned long reset;
+};
+
 struct pcap_rx_queue {
        uint16_t port_id;
        uint16_t queue_id;
        struct rte_mempool *mb_pool;
        struct queue_stat rx_stat;
+       struct queue_missed_stat missed_stat;
        char name[PATH_MAX];
        char type[ETH_PCAP_ARG_MAXLEN];
 
@@ -144,6 +154,56 @@ RTE_LOG_REGISTER(eth_pcap_logtype, pmd.net.pcap, NOTICE);
        rte_log(RTE_LOG_ ## level, eth_pcap_logtype, \
                "%s(): " fmt "\n", __func__, ##args)
 
+static struct queue_missed_stat*
+queue_missed_stat_update(struct rte_eth_dev *dev, unsigned int qid)
+{
+       struct pmd_internals *internals = dev->data->dev_private;
+       struct queue_missed_stat *missed_stat =
+                       &internals->rx_queue[qid].missed_stat;
+       const struct pmd_process_private *pp = dev->process_private;
+       pcap_t *pcap = pp->rx_pcap[qid];
+       struct pcap_stat stat;
+
+       if (!pcap || (pcap_stats(pcap, &stat) != 0))
+               return missed_stat;
+
+       /* rollover check - best effort fixup assuming single rollover */
+       if (stat.ps_drop < missed_stat->pcap)
+               missed_stat->mnemonic += UINT_MAX;
+       missed_stat->pcap = stat.ps_drop;
+
+       return missed_stat;
+}
+
+static void
+queue_missed_stat_on_stop_update(struct rte_eth_dev *dev, unsigned int qid)
+{
+       struct queue_missed_stat *missed_stat =
+                       queue_missed_stat_update(dev, qid);
+
+       missed_stat->mnemonic += missed_stat->pcap;
+       missed_stat->pcap = 0;
+}
+
+static void
+queue_missed_stat_reset(struct rte_eth_dev *dev, unsigned int qid)
+{
+       struct queue_missed_stat *missed_stat =
+                       queue_missed_stat_update(dev, qid);
+
+       missed_stat->reset = missed_stat->pcap;
+       missed_stat->mnemonic = 0;
+}
+
+static unsigned long
+queue_missed_stat_get(struct rte_eth_dev *dev, unsigned int qid)
+{
+       const struct queue_missed_stat *missed_stat =
+                       queue_missed_stat_update(dev, qid);
+
+       return missed_stat->pcap + missed_stat->mnemonic - missed_stat->reset;
+}
+
 static int
 eth_pcap_rx_jumbo(struct rte_mempool *mb_pool, struct rte_mbuf *mbuf,
                const u_char *data, uint16_t data_len)
@@ -621,6 +681,7 @@ eth_dev_stop(struct rte_eth_dev *dev)
 
        /* Special iface case. Single pcap is open and shared between tx/rx. */
        if (internals->single_iface) {
+               queue_missed_stat_on_stop_update(dev, 0);
                pcap_close(pp->tx_pcap[0]);
                pp->tx_pcap[0] = NULL;
                pp->rx_pcap[0] = NULL;
@@ -641,6 +702,7 @@ eth_dev_stop(struct rte_eth_dev *dev)
 
        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                if (pp->rx_pcap[i] != NULL) {
+                       queue_missed_stat_on_stop_update(dev, i);
                        pcap_close(pp->rx_pcap[i]);
                        pp->rx_pcap[i] = NULL;
                }
@@ -685,6 +747,7 @@ eth_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats)
 {
        unsigned int i;
        unsigned long rx_packets_total = 0, rx_bytes_total = 0;
+       unsigned long rx_missed_total = 0;
        unsigned long tx_packets_total = 0, tx_bytes_total = 0;
        unsigned long tx_packets_err_total = 0;
        const struct pmd_internals *internal = dev->data->dev_private;
@@ -695,6 +758,7 @@ eth_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats)
                stats->q_ibytes[i] = internal->rx_queue[i].rx_stat.bytes;
                rx_packets_total += stats->q_ipackets[i];
                rx_bytes_total += stats->q_ibytes[i];
+               rx_missed_total += queue_missed_stat_get(dev, i);
        }
 
        for (i = 0; i < RTE_ETHDEV_QUEUE_STAT_CNTRS &&
@@ -708,6 +772,7 @@ eth_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats)
 
        stats->ipackets = rx_packets_total;
        stats->ibytes = rx_bytes_total;
+       stats->imissed = rx_missed_total;
        stats->opackets = tx_packets_total;
        stats->obytes = tx_bytes_total;
        stats->oerrors = tx_packets_err_total;
@@ -724,6 +789,7 @@ eth_stats_reset(struct rte_eth_dev *dev)
        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                internal->rx_queue[i].rx_stat.pkts = 0;
                internal->rx_queue[i].rx_stat.bytes = 0;
+               queue_missed_stat_reset(dev, i);
        }
 
        for (i = 0; i < dev->data->nb_tx_queues; i++) {