Hi Zhike,
I've tested the behavior before and after this patch and can verify that the
packets are being correctly truncated.
Code looks good to me too.
Reviewed-by: Cian Ferriter <cian.ferri...@intel.com>
Thanks,
Cian
> -----Original Message-----
> From: Zhike Wang <wangzk...@163.com>
> Sent: Monday 9 December 2019 01:53
> To: dev@dpdk.org
> Cc: wangzh...@jd.com; Yigit, Ferruh <ferruh.yi...@intel.com>; Ferriter, Cian
> <cian.ferri...@intel.com>; Zhike Wang <wangzk...@163.com>
> Subject: [PATCH v2] net/pcap: truncate packet if it is too large
>
> From: Zhike Wang <wangzh...@jd.com>
>
> Previously large packet would be dropped, instead now it is better to keep it
> via truncating it.
>
> Signed-off-by: Zhike Wang <wangzk...@163.com>
> ---
> drivers/net/pcap/rte_eth_pcap.c | 16 ++++++----------
> 1 file changed, 6 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/net/pcap/rte_eth_pcap.c
> b/drivers/net/pcap/rte_eth_pcap.c index aa7ef6f..b4c79d1 100644
> --- a/drivers/net/pcap/rte_eth_pcap.c
> +++ b/drivers/net/pcap/rte_eth_pcap.c
> @@ -313,7 +313,7 @@ struct pmd_devargs_all {
> struct pcap_pkthdr header;
> pcap_dumper_t *dumper;
> unsigned char temp_data[RTE_ETH_PCAP_SNAPLEN];
> - size_t len;
> + size_t len, caplen;
>
> pp = rte_eth_devices[dumper_q->port_id].process_private;
> dumper = pp->tx_dumper[dumper_q->queue_id];
> @@ -325,28 +325,24 @@ struct pmd_devargs_all {
> * dumper */
> for (i = 0; i < nb_pkts; i++) {
> mbuf = bufs[i];
> - len = rte_pktmbuf_pkt_len(mbuf);
> + len = caplen = rte_pktmbuf_pkt_len(mbuf);
> if (unlikely(!rte_pktmbuf_is_contiguous(mbuf) &&
> len > sizeof(temp_data))) {
> - PMD_LOG(ERR,
> - "Dropping multi segment PCAP packet. Size
> (%zd) > max size (%zd).",
> - len, sizeof(temp_data));
> - rte_pktmbuf_free(mbuf);
> - continue;
> + caplen = sizeof(temp_data);
> }
>
> calculate_timestamp(&header.ts);
> header.len = len;
> - header.caplen = header.len;
> + header.caplen = caplen;
> /* rte_pktmbuf_read() returns a pointer to the data directly
> * in the mbuf (when the mbuf is contiguous) or, otherwise,
> * a pointer to temp_data after copying into it.
> */
> pcap_dump((u_char *)dumper, &header,
> - rte_pktmbuf_read(mbuf, 0, len, temp_data));
> + rte_pktmbuf_read(mbuf, 0, caplen, temp_data));
>
> num_tx++;
> - tx_bytes += len;
> + tx_bytes += caplen;
> rte_pktmbuf_free(mbuf);
> }
>
> --
> 1.8.3.1
>
