Re: [dpdk-dev] [PATCH v2] app/testpmd: make txonly mode generate multiple flows

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

Hi,

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Yongseok Koh
> Sent: Wednesday, January 17, 2018 6:19 PM
> To: Lu, Wenzhuo <wenzhuo.lu@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>
> Cc: dev@dpdk.org; Yongseok Koh <yskoh@mellanox.com>
> Subject: [dpdk-dev] [PATCH v2] app/testpmd: make txonly mode generate multiple flows
> 
> Testpmd can generate multiple flows without taking much cost and this could
> be a simple traffic generator for developer's quick tests. IP destination
> address is varied.

Correct me if I am wrong - but that the change of existing behavior.
Without any announcement and without ability to the user to keep
current one (command-line option, new CLI command, etc.).
What if there are people who rely on existing behavior
(some test scripts or so)?
Konstantin

> 
> Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
> ---
> 
> v2:
> * Add detailed explanation in a comment.
> 
>  app/test-pmd/txonly.c | 15 ++++++++++++++-
>  1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/app/test-pmd/txonly.c b/app/test-pmd/txonly.c
> index 1f08b6ed3..253cf2385 100644
> --- a/app/test-pmd/txonly.c
> +++ b/app/test-pmd/txonly.c
> @@ -44,7 +44,7 @@
>  #define UDP_DST_PORT 1024
> 
>  #define IP_SRC_ADDR ((192U << 24) | (168 << 16) | (0 << 8) | 1)
> -#define IP_DST_ADDR ((192U << 24) | (168 << 16) | (0 << 8) | 2)
> +#define IP_DST_ADDR ((192U << 24) | (168 << 16))
> 
>  #define IP_DEFTTL  64   /* from RFC 1340. */
>  #define IP_VERSION 0x40
> @@ -52,6 +52,7 @@
>  #define IP_VHL_DEF (IP_VERSION | IP_HDRLEN)
> 
>  static struct ipv4_hdr  pkt_ip_hdr;  /**< IP header of transmitted packets. */
> +static __thread uint8_t ip_var; /**< IP address variation */
>  static struct udp_hdr pkt_udp_hdr; /**< UDP header of transmitted packets. */
> 
>  static void
> @@ -159,6 +160,7 @@ pkt_burst_transmit(struct fwd_stream *fs)
>  	struct rte_mbuf *pkt_seg;
>  	struct rte_mempool *mbp;
>  	struct ether_hdr eth_hdr;
> +	struct ipv4_hdr *ip_hdr;
>  	uint16_t nb_tx;
>  	uint16_t nb_pkt;
>  	uint16_t vlan_tci, vlan_tci_outer;
> @@ -237,6 +239,17 @@ pkt_burst_transmit(struct fwd_stream *fs)
>  		copy_buf_to_pkt(&eth_hdr, sizeof(eth_hdr), pkt, 0);
>  		copy_buf_to_pkt(&pkt_ip_hdr, sizeof(pkt_ip_hdr), pkt,
>  				sizeof(struct ether_hdr));
> +		ip_hdr = rte_pktmbuf_mtod_offset(pkt, struct ipv4_hdr *,
> +						 sizeof(struct ether_hdr));
> +		/*
> +		 * Generate multiple flows by varying IP dest addr. This enables
> +		 * packets are well distributed by RSS in receiver side if any
> +		 * and txonly mode can be a decent packet generator for
> +		 * developer's quick performance regression test.
> +		 */
> +		ip_hdr->dst_addr =
> +			rte_cpu_to_be_32(IP_DST_ADDR | (ip_var++ << 8) |
> +					 (rte_lcore_id() + 1));
>  		copy_buf_to_pkt(&pkt_udp_hdr, sizeof(pkt_udp_hdr), pkt,
>  				sizeof(struct ether_hdr) +
>  				sizeof(struct ipv4_hdr));
> --
> 2.11.0