On Wed, Nov 04, 2015 at 06:54:16PM +0800, Jijiang Liu wrote:
> Change the vhost sample to support and test TX offload.
>
> Signed-off-by: Jijiang Liu <jijiang.liu at intel.com>
> ---
> examples/vhost/main.c | 128
> ++++++++++++++++++++++++++++++++++++++++++-------
> 1 files changed, 111 insertions(+), 17 deletions(-)
>
> diff --git a/examples/vhost/main.c b/examples/vhost/main.c
> index 9eac2d0..06e1e8b 100644
> --- a/examples/vhost/main.c
> +++ b/examples/vhost/main.c
> @@ -50,6 +50,10 @@
> #include <rte_string_fns.h>
> #include <rte_malloc.h>
> #include <rte_virtio_net.h>
> +#include <rte_tcp.h>
> +#include <rte_ip.h>
> +#include <rte_udp.h>
> +#include <rte_sctp.h>
>
> #include "main.h"
>
> @@ -140,6 +144,8 @@
>
> #define MBUF_EXT_MEM(mb) (rte_mbuf_from_indirect(mb) != (mb))
>
> +#define VIRTIO_TX_CKSUM_OFFLOAD_MASK (PKT_TX_IP_CKSUM | PKT_TX_L4_MASK)
> +
> /* mask of enabled ports */
> static uint32_t enabled_port_mask = 0;
>
> @@ -197,6 +203,13 @@ typedef enum {
> static uint32_t enable_stats = 0;
> /* Enable retries on RX. */
> static uint32_t enable_retry = 1;
> +
> +/* Disable TX checksum offload */
^^^^^^^
You meant to "Enable"?
> +static uint32_t enable_tx_csum;
> +
> +/* Disable TSO offload */
> +static uint32_t enable_tso;
Actually, I'd like to see TSO/CSUM offloading is enabled by default:
they are so common, and they are enabled in a lot places by default,
say, kernel, qemu. There is no reason to make it "disable" here.
> +
> /* Specify timeout (in useconds) between retries on RX. */
> static uint32_t burst_rx_delay_time = BURST_RX_WAIT_US;
> /* Specify the number of retries on RX. */
> @@ -292,20 +305,6 @@ struct vlan_ethhdr {
> __be16 h_vlan_encapsulated_proto;
> };
>
> -/* IPv4 Header */
> -struct ipv4_hdr {
> - uint8_t version_ihl; /**< version and header length */
> - uint8_t type_of_service; /**< type of service */
> - uint16_t total_length; /**< length of packet */
> - uint16_t packet_id; /**< packet ID */
> - uint16_t fragment_offset; /**< fragmentation offset */
> - uint8_t time_to_live; /**< time to live */
> - uint8_t next_proto_id; /**< protocol ID */
> - uint16_t hdr_checksum; /**< header checksum */
> - uint32_t src_addr; /**< source address */
> - uint32_t dst_addr; /**< destination address */
> -} __attribute__((__packed__));
Minor nit: it's a cleanup, having nothing to do with this patch (to
demonstrate TSO/CSUM). It belongs to another patch.
> -
> /* Header lengths. */
> #define VLAN_HLEN 4
> #define VLAN_ETH_HLEN 18
> @@ -441,6 +440,14 @@ port_init(uint8_t port)
>
> if (port >= rte_eth_dev_count()) return -1;
>
> + if (enable_tx_csum == 0)
> + rte_vhost_feature_disable(1ULL << VIRTIO_NET_F_CSUM);
> +
> + if (enable_tso == 0) {
> + rte_vhost_feature_disable(1ULL << VIRTIO_NET_F_HOST_TSO4);
> + rte_vhost_feature_disable(1ULL << VIRTIO_NET_F_HOST_TSO6);
> + }
> +
> rx_rings = (uint16_t)dev_info.max_rx_queues;
> /* Configure ethernet device. */
> retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
> @@ -576,7 +583,9 @@ us_vhost_usage(const char *prgname)
> " --rx-desc-num [0-N]: the number of descriptors on rx, "
> "used only when zero copy is enabled.\n"
> " --tx-desc-num [0-N]: the number of descriptors on tx, "
> - "used only when zero copy is enabled.\n",
> + "used only when zero copy is enabled.\n"
> + " --tx-csum [0|1] disable/enable TX checksum offload.\n"
> + " --tso [0|1] disable/enable TCP segement offload.\n",
> prgname);
> }
>
> @@ -602,6 +611,8 @@ us_vhost_parse_args(int argc, char **argv)
> {"zero-copy", required_argument, NULL, 0},
> {"rx-desc-num", required_argument, NULL, 0},
> {"tx-desc-num", required_argument, NULL, 0},
> + {"tx-csum", required_argument, NULL, 0},
> + {"tso", required_argument, NULL, 0},
> {NULL, 0, 0, 0},
> };
>
> @@ -656,6 +667,28 @@ us_vhost_parse_args(int argc, char **argv)
> }
> }
>
> + /* Enable/disable TX checksum offload. */
> + if (!strncmp(long_option[option_index].name, "tx-csum",
> MAX_LONG_OPT_SZ)) {
> + ret = parse_num_opt(optarg, 1);
> + if (ret == -1) {
> + RTE_LOG(INFO, VHOST_CONFIG, "Invalid
> argument for tx-csum [0|1]\n");
> + us_vhost_usage(prgname);
> + return -1;
> + } else
> + enable_tx_csum = ret;
> + }
> +
> + /* Enable/disable TSO offload. */
> + if (!strncmp(long_option[option_index].name, "tso",
> MAX_LONG_OPT_SZ)) {
> + ret = parse_num_opt(optarg, 1);
> + if (ret == -1) {
> + RTE_LOG(INFO, VHOST_CONFIG, "Invalid
> argument for tso [0|1]\n");
> + us_vhost_usage(prgname);
> + return -1;
> + } else
> + enable_tso = ret;
> + }
> +
> /* Specify the retries delay time (in useconds) on RX.
> */
> if (!strncmp(long_option[option_index].name,
> "rx-retry-delay", MAX_LONG_OPT_SZ)) {
> ret = parse_num_opt(optarg, INT32_MAX);
> @@ -1114,6 +1147,63 @@ find_local_dest(struct virtio_net *dev, struct
> rte_mbuf *m,
> return 0;
> }
>
> +static uint16_t
> +get_psd_sum(void *l3_hdr, uint64_t ol_flags)
> +{
> + if (ol_flags & PKT_TX_IPV4)
> + return rte_ipv4_phdr_cksum(l3_hdr, ol_flags);
> + else /* assume ethertype == ETHER_TYPE_IPv6 */
> + return rte_ipv6_phdr_cksum(l3_hdr, ol_flags);
> +}
> +
> +static void virtio_tx_offload(struct rte_mbuf *m)
> +{
> + void *l3_hdr;
> + struct ipv4_hdr *ipv4_hdr = NULL;
> + struct tcp_hdr *tcp_hdr = NULL;
> + struct udp_hdr *udp_hdr = NULL;
> + struct sctp_hdr *sctp_hdr = NULL;
> + struct ether_hdr *eth_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
> +
> + l3_hdr = (char *)eth_hdr + m->l2_len;
> +
> + if (m->ol_flags & PKT_TX_IPV4) {
> + ipv4_hdr = (struct ipv4_hdr *)l3_hdr;
> + if (m->ol_flags & PKT_TX_IP_CKSUM)
> + ipv4_hdr->hdr_checksum = 0;
> + }
> +
> + if (m->ol_flags & PKT_TX_L4_MASK) {
> + switch (m->ol_flags & PKT_TX_L4_MASK) {
> + case PKT_TX_TCP_CKSUM:
> + tcp_hdr = (struct tcp_hdr *)
> + ((char *)l3_hdr + m->l3_len);
> + tcp_hdr->cksum = get_psd_sum(l3_hdr, m->ol_flags);
I'm wondering that's necessary here (even for the data going through
nic). AFAIK, the kernel sending the data will calculate pseudo checksum.
(I may be wrong; a simple validation could prove that)
--yliu
